 Good morning America. Good morning Europe. Good evening Asia. I'm each a professor of material science and engineering at Stanford and SLAC National Lab. On behalf of my co-chair, Professor William Che, I proudly announce the launch of Storage X International Symposium. This is a weekly online event. We all know COVID-19 has changed the way how we interact as scientists. We hope these Storage X symposium can bring scientists around the world together to present discussed results and ideas on energy storage and offer a platform for academia and industry to interact for students to learn. This Storage X symposium is supported by Stanford Storage Initiative and also supported by Stanford Preco Institute for Energy. This planning of symposium is not possible without the strong support of many staff, Jimmy Chen, Tracy Turner, our graduate student William Huang, and also our IT support Justin Warren and Sarah Weaver. To kick off today's launching of the event, I'm very proud to have two leading scientists today to give two seminars on the topic of energy storage. The first speaker requires very little introduction as well as the second speaker. We have Professor Stan Wittingham from Binghamton University and Professor Jun Liu from PNNL National Lab and Washington University. Stan, of course, everybody knows he is a pioneer of lithium ion batteries and intercalation chemistry. To recognize his contribution, he was awarded the Nobel Prize in Chemistry in 2019 for his contribution really starting the whole field of lithium ion batteries together with John Goodenough and Yoshino. Jun, of course, we all know as well and he's a leading scientist in the world, particularly working on materials designed for batteries, especially for the next generation of lithium ion batteries. He is also a director of a battery 500 consortium. Without further ado, I will hand it over to Stan to kick off today's symposium. Stan. Thank you. Okay, thank you. What I want to do is really go back almost or 50 years and show you how the lithium battery ideas got started and then show you a couple of challenges that are present today and I'll show you my relationship to a number of institutions on the way. So I went to school in Britain as most of you can probably hear at Stanford. I then spent seven years, eight years at Oxford for both my bachelor's and doctorate degrees. Then I went to sunny California to Stanford for four years, so that's my relationship with Stanford. Then I went to what was then ESO, now Exxon or ExxonMobil and I'm now presently at Binghamton. Just in cases, people who don't study the history. Battery started out more than two centuries ago by Walter and if you go to Lake Como, you'll be able to go to see the temple they built in his honor there and some beautiful views of the Alps behind the temple. But the person who really laid the foundation for electrochemistry was Michael Faraday in Britain and he was around shortly after Walter. So those are the two folks we need to honor for what they did. I had two great experiences and I want to describe a little bit about both of them. You'll see how this led into lithium-ion battery. One was Peter Dickens, my tutor and advisor Oxford in New College and I should emphasize that at that time Oxford had three chemistry departments inorganic, physical and organic and inorganic included metallurgy and crystallography. So material science was really part of inorganic chemistry at that time. Then I came to Stanford and worked with Bob Huggins for four years and in addition to great science there, that's why I met my wife and our children were both born in that area. So that Stanford was a critical step in my life. So let's just look at really the precursors to lithium-ion batteries. I looked at compounds called tungsten bronzes. These are multicolored materials whose color depends on the amount of alkali metal and therefore on the amount of the electron concentration and are now used in electrochromic displays. But we found out the ions can move very fast through the lattices and there are at least three different structures I showed through them here. For my bachelor's degree in Oxford you have spent a year of research for your bachelor's degree. I actually looked at some catalysis reactions on these materials and showed the impact of structure both electronic and crystalline structures. Then for my doctorate I actually looked at how these reduced through tungsten metal because in making tungsten filament you add a little bit of sodium which is sodium bronze to the mix and we showed in all these all the alkali ions moved extremely fast. Then when I went to Stanford we actually did a fundamental study of the thermodynamics of formation of these materials and this was published in an NBS special publication and we were able to grow single crystals up to a centimeter on the side as cubes and dodecahedrons. What really happened almost exactly the same time is Yau and Kumar Ford Motor Company discovered the very high ionic conductivity and sodium beta alumina. The sodium ions moved almost as fast as an aqueous solutions and they at that time proposed a sodium sulfur battery and their publication in 1967 really led to many other searches high ionically conducting materials. Prior to that time it's really only thought that silver moved faster materials and as a result John Gooden have started looking at NASA con and if you look at the title of this slide Bob and I created this title and this was also published by NBS that's beta alumina prelude to a revolution solid-state electrochemistry. I'm not sure we thought we'd be as right as we were but the field really blossomed after that time. So let's just look at what beta alumina is for a second. It's a layered structure. It was called beta alumina because it just thought we had different form of aluminum oxide but it was Linus Pauling who worked out the structure and found out that sodium ions were critical to the structure and I show you the structure on the left here it's four layers of gamma alumina then you have this very open structure with oxygen bridges and then the sodium or the ions inserted between them and it's absolutely critical to the ionic conductivity that you have excess sodium and it turns out this is about 15% and you can see these excess ions in as dumbbells here and another one over here without those the ionic conductivity is not good at all so why were we interested in that? Well we wanted to actually measure how fast the sodium ions moved in beta alumina they moved far too fast for one to use the typical inert platinum electrodes so we basically had to build a cell where the electrodes were both reversible to sodium ions and to electrons and the ideal materials were these tungsten bronzes or the analogous vanadium materials which we call metallic mixed conductors and really this is now if you like a battery if you had the different compositions of the bronzes so I show you here a picture of what we had we had a sodium beta alumina single crystal and I should say beta alumina was used as large bricks to line glass tanks so you could chip out large single crystals up to an inch in length here then we put the bronze electrodes on each side and on the right hand side you can see the ionic conductivity we measured from 800 degrees centigrade down to um liquid nitrogen temperatures and you'll notice it's a single mechanism the whole way and I think it's still probably the one material that has the highest single mechanism of the largest temperature range so we'd shown we could build a a system to measure ionic conductivity on moving to Exxon we started getting interest in battery chemistry and it may surprise you if to learn if you actually looked at all the publications at that time they did not understand role of intercalation or that you could have non-stochometric ternary phases so it was assumed in for example in V2O5 you have extracted oxygen from the lattice and the alkaline cell you're also an abstracted oxygen so you change the structure at room temperature which is really not all that realistic in reality what happens in these you are intercalating lithium in the vanadium oxide lattice and in the case of the alkaline cell you're intercalating protons into that lattice forming hydroxyl bonds and we published that in mid-70s in the electrochemical society and this really led to the whole concept of intercalation chemistry and this role in electrochemistry and as we know these ternary phases are extremely common at room temperature so it's interesting to go back and look at what intercalation is described as if you go back and look at a dictionary 30 or 40 years old it will mention in that February 29th as an example of intercalation you stick it in the calendar one year then take it back out or as the Romans did they forgot two months and intercalate the January and February into the calendar if you pick up a present day dictionary the first example will be a chemical example of intercalating lithium into some material and as we showed in the 70s you're not talking just about ions you can put molecules DNA large length amines in all these materials they're extremely flexible and I show you the example of TIS2 schematic there we go basically from 5.7 angstroms it expands to 6.2 angstroms and essentially as you put the lithium in you're putting electrons into the conduction band so a very simple reaction and in this case it's a single phase all the way from zero lithium to one lithium and this shows you a very old electrochemical cycling system this was back in 1973 I think and you'll notice we ran it at about 10 milliamps per square centimeter and I look back at some of our old patterns the loading in some of these cells varied from about 20 or 30 milligrams per sweat centimeter up to 100 milligrams per square centimeter we had the big advantages that titanium disulfide is essentially a metallic conductor so you don't need any carbon black so the reaction can occur at all points on the material and the other thing I pointed out earlier there's no phase transition here so there's no nucleation energy so it cycles very very readily the difference between the charge and discharge here is just the IR loss so if you go back to look at what ESO did they really took the initiative to invest in all sorts of new energies solar cells fuel cells batteries amongst others and spent many millions of dollars in this area because they thought it was important and in this picture you show me with a slightly I would say old fashions while the large lapels and on the right hand side you'll see what we use these are single crystals and I noticed single crystals are back in vogue now so we use single crystals of various shapes just as Sony events we use single crystals of lithium cobalt oxide and this is what we built the cells out of so a little bit of history here and I'll repeat this in the next slide as well so and it was in the 1970s we worked on titanium disulfide for safety we actually used aluminum anode so we use a lithium aluminum alloy as the anode and I show you you two cells here one cell here this is about six inches by four inches by about an inch thick this was shown at the eb show in 1977 and it drove a motor cycle headlamp on and off all week long and then the top right here is a marketing giveaway a paperweight that has a solar cell and it's a battery and a little clock this particular one still sits in my office it still works and if you go to a Nobel museum you'll see a number of these batteries there that we gave to them which we fortunately could find last December so they well made lithium batteries last forever about 10 years later molly energy in british columbia manufactured many lithium batteries and jeff darm was associated with that jeff in fact did his phd on titanium disulfide but they decided to use molybdenum disulfide because molybdenite is a natural ore in british columbia so they could just dig it up a little bit later john godin of adoxford have been read out tis to work he was working on cobalt oxides for their magnetic behavior decided to try it as a battery cathode and you all know what happened after that it was a great success around about the same time there was a lot of interest in removing the lithium anode making it safer and yeshino who was in a company then was looking at polyacetylene and some coax and found he could readily intercalate lithium in and out of those materials and they eventually worked closely with sony to commercialize the cells in 1991 using basically a graphitic carbon and single crystals of lithium cobalt oxide and you'll see on the right hand side a picture taken two years ago where john and i were together at a batty 500 consortium meeting i think in berkeley so john and i are still working together to push the frontiers forward let's just look at bits schematic in cases anybody who doesn't know what a intercalation cell is all the batteries they still use this 1970s technology where we store lithium in two materials with the different and free ranges of formation and then just shuttle a lithium between the two sides from the anode here to the cathode to an organic electrolyte and here are the various different stages from 1972 we started with lithium went to lithium aluminum then yeshino put in carbon and there's been a lot of interest in lately in tin or silicon and now ideal we'd like to go back to lithium and i'm sure john will discuss that a little bit so that's the anode side and the cathode side we start with tis2 then switch to the analogous oxides which john did at oxford and it good to point out here as i did in my banquet speech in stock home i did my work as an englishman in america john did his work as an american in england then from cobalt oxide he went to the mixed metal oxides then john came up with the olivine structures both the iron compound and now this interest in the manganese phosphate because of its higher voltage and now i'll show you one slide a little bit later phosphates are much more stable and therefore safer but they're too low an inch density for many applications so the interest is can we pump two lithium ions into some of these materials so we actually look at what we get out of today's batteries it is not all that impressive so of today's batteries we get much less than 30 percent of their theoretical volumetric or gravimetric capacity and one of the main culprits here is the carbon anode it takes up half the volume of the cell and needs 70 grams to store seven grams of lithium so the ideal will be try to make lithium metal work and maybe an intermediate stage would be to go to silicon it's not working too well because it's too reactive and we've been looking at um tin iron complexes it replaced the tin cobalt that sony worked on a while back tin iron has about a 99.95 percent columbic efficiency so very good but tin is a little bit heavy and expensive on the cathode side we really need to use all the lithium in the materials so on the layered oxides we maybe use only two thirds and on the phosphates we need stuff more lithium in there in addition we need to make the cathode materials behave more like titanium disulfide in other words increase the ionic and the electronic conductivity this would let us use thicker electrodes which would reduce the amount of current collector and the separator so let's just look at one of the issues of these layered oxides basically on the first cycle we leave about 12 percent of the capacity of the material unused if we could use that material we could fairly easily attain over 400 watt hour kilograms cells and maybe even get to 500 500 that would just be getting to 50 percent of the theoretical capacity and that show you here this is the typical loss sometimes is quite a bit higher than this but this is independent of rate it's independent of um the nickel content but interestingly it doesn't show up in the tin cobalt oxide it doesn't show up in titanium disulfide and it doesn't show up in the olivines so we measure the diffusion coefficient of these materials and you can see it's fairly high about 10 to the minus nine at low lithium contents then falls off the cliff as we get the high lithium contents and this is the reason why we can't get all the lithium back in if we just increase the temperature to 45 degrees centigrade we can certainly get all that lithium in so it's clearly a kinetic phenomenon which we need to solve so question we asked ourselves is is it feasible to put two lithium ions into a crystalline lattice without damaging that crystalline lattice we knew it had been done in vanadium disulfide back in uh um exon days and Mike Thackeray it's shown you could put it in some of the layered oxides but at a very low voltage so we chose to work on a vanille phosphate and obviously i wouldn't be discussing this and unless it worked and this was one of only two battery related activities and the only EFR related activity that was in the White House's technology report of last year and you can see the two students we highlighted there one from my group and one from Claire Gray's group at Cambridge who got the award for from DOE for one of the best um inventions of the first 10 years of the EFRC's so let's look at this material you'll see that this material it's very well known material it is forms at least i think seven different phases this particular phase which we call the epsilon phase was discovered by Alan Jacobson also at Exon at that time and we spent many years trying to make this in a form that would get good electrochemistry out of it and we found out we could make it by a hydrothermal approach where we got these nice little cuboids about 100 to 200 nanometers particle sizes if you get larger particles and have to grind it you then damage the crystal structure and it doesn't cycle so well and what is remarkable about this material if you look at it here the first 50 cycles and the worst one of these cycles is in fact the first one here to here more polarization as we cycle it more and more it gets better and better so this has about 300 milliampere hours per gram right now it's really we've shown I think proof of concept you can put two alkali ions into a crystal lattice without damaging that lattice there are still challenges here this material is used as an oxidation catalyst by the petroleum industry so it tends to react with some of the solvents so the coulombic efficiency is about 98 99 percent so we have to get that up to a 100 percent and we have to improve the rate capability but it's proof of principle we can go beyond the single lithium systems a key thing that happened late last year basically whilst we were in stock home is that the space station replaced all the nickel metal hydride batteries with lithium ion batteries and these were the two astronauts at that time who spoke to us and discussed how they replaced lithium ion batteries and that they now used half the number of batteries they used to use and the batteries would last twice as long so they were very happy with lithium ion so lithium ion has made it splash out there in the space station and I think maybe it's important to point out it was this lady who was born in main us of swedish parents she and her colleague with the two went outside the space shuttle to install the batteries in the system so let me just finish showing you a few examples of where lithium batteries are now dominant we can clearly clean the environment with electric vehicles there are a lot of challenges still and I show you for examples here this picture in the middle here is a small electric vehicle one of the first half dozen on Bermuda where my wife and I rented one for our 50th anniversary last year and the thing we found out very quickly is range anxiety is real we were told our charging stations at the far end of the island but charge it before you come back we went to the far end of the island they were still building the recharging stations so we stopped partway back got it recharged and just managed to creep back on the right hand side are two two large trucks one a 16 wheeler and the other one a garbage truck being tested by Peterbilt up north of Seattle I should thank John Liu for taking us there so these large trucks are going all electric and this particular truck I understand is in the Los Angeles docks taking the large trailer units around there the other key aspect of batteries where they can help us is in enabling renewable energy no solar and wind only operate parts of the daytime normally so we have to store the energy funders so we can use it when we want to use it so this will give us a cleaner more sustainable technology and an interesting example here is in Binghamton almost 10 years ago now they installed a small lithium-ion battery system about four megawatt hours next to a coal power plant and within two months they turned off the coal power planters never come back on again so we can wipe out small pica plants by using storage and storage is clearly critical in mitigating global warming and it gives us a more efficient grid and clearly as everyone knows it's a enable the communications revolution and at the bottom right I show you here this is the British ambassador's residence in Stockholm and for the Nobel session she brought over two vehicles from London the one on left is a all-electric Jaguar and the one on the right is a all-electric London taxi built-in collaboration with Volvo in Sweden and they used the taxi to take them to the palace for the various receptions so the British were certainly very excited and very interested in going electric and they're pushing this particularly in large cities like London and I spent going to find like place like New York, San Francisco, Tokyo and so on are going to be pushing for all electric in the future and I will stop there thank you very much well thank you very much Stan for the very very nice overview of the past history as well as what can be done for the future and let me report back to you and do a lot of people now watching these symposium online in zoom right here we have about 560 people and then we also have a view on our storage x website there are more than that's about close to 3 000 people right there watching the audience raised many great questions I think I can only pick a few to you know to ask you due to the time limitation so the first question Stan is about high nickel cathode there are actually a number of questions right there I can dance them into one question okay asking about the prospect of high nickel cathode also asking about these nickel cathode a11 what how fast is the lithiation in the lithiation kinetics as well as they're wondering the safety of high nickel cathode I'll start from this question okay I think first thing I think the high nickel gives you a higher energy density but industry is as much interested in high nickel because it reduces the cobalt content and going from 333 to I think 622 or 532 has cut the cost of the cathode by about 40% so there's that huge driving force it's my understanding auto industry is now using 622 and some people say they're already beginning to use 811 and that's not too different to what Tesla is using with nca so the answer is the hazard level does increase as you increase the nickel content but in some ways it's still the lithium anode is the most hazardous part of the cell if you cycle it many times there's some pulverization of the graphite there so I think they're fairly safe but the higher nickel you go there's more gassing so you're tending to having to use hard side cells you can't use pouch cells at very high nickel content so there are some limitations but it's going to be a huge drive to go to high nickel and clearly if people could go to high manganese and make that work that'd be much lower cost yeah very very good Stan the second question there's a person asking I also want to ask this question as well we know for the battery research going from starting until it's successfully commercialized it could take a long time and for your initial you know invention in the 1970s of anode using lithium aluminum cathode is a titanium sulfide from research starting to make that into commercial product how long did it take well Exxon was trying to sell commercial products in about I was saying 1978 1980 account alpha testing so they sold them in fact to some watch companies initially they were going to build electric vehicles but they decided they're better alpha tested than some smaller devices first and then those days watches used LEDs which used much more energy than LCDs so primary cell would die out in about a week so they wanted rechargeable cells so they used that Mali energy in fact built large manufacturing effort with aluminum disulfide the problem was they used pure metal anode and had in the end many accidents so they had to stop doing that so really the first it took since the almost 20 years before Sony actually made money out of batteries so the first 20 years people weren't making money and it was Sony who really using vertical integration they wanted the battery and everything to the actual device yeah so roughly I see 1973 you work on titanium sulfide to have the kind of better you know better coming out about six seven years right and then later to the I think a larger-scale commercialization when Sony come along that's about close to 20 years yeah that will be the time people should expect yes okay so let's just say that's partly why industry is not too happy about investing in batteries they look at that and say well your patent issued in the mid-70s by telling me making money the patents almost expired that's the challenging for the whole field next question Stan there is an audience also want you to comment on the solid state batteries the future of solid state batteries well you saw the device we used to measure beta aluminum was totally solid state I think solid state will be safer I think the big question today is how solid is solid so the real issue on all solid state batteries the interfaces and there's any expansion at all those interfaces going to crack so I always when somebody tells me they've got this great solid state battery I asked them how many drops of liquid you put on each side because you may need something to grease the interfaces but I think no solid state is a way to go it certainly will be much safer than other approaches but the real challenge is can you manufacture it as cheaply as you manufacture using today's roll-to-roll technology now I know folks like applied materials in Santa Clara just south of you are obviously pushing that avenue trying to use semiconductor technology but suddenly I think solid state is a way to go it's not the penacea everybody thinks it is dendrites grow very happily through ceramics maybe even happier than through liquid electrolytes yeah I think there's a lot of young students in the audience so this will be a good research topic they can they can work on just many exciting problems right there but if they can solve those problems the future could be very bright so good for young so good for young students to think about okay stand is also a question about magnesium batteries organic batteries this this person asking and what's your thought about this I think overall this person is asking a post lithium ion batteries and what's the what what do you want to bet on which one do you want to bet on I think we often get these questions myself I think you get this question all the time yeah well what's your thought of magnesium and organic materials as a electrode for the batteries I'm on the record saying magnesium has no chance whatsoever and the theorists knew it or should have known it um and on van de ben a few years ago there's some beautiful calculations and showed and they used tis2 as an example that the voltage for magnesium is one volt less than lithium not the half volt people thought and so that immediately cuts the energy density and the magnesium ion is so polarizing it will not move very fast and about a year after that linda nayser actually built cells magnesium tis2 in the two different forms of tis2 and I don't know I should say reproduce the theoretical results almost exactly and showed that the energy density of the magnesium cells were less than half that of the lithium cells the interesting thing on magnesium I don't understand is no one has been able to put more than one electron per magnesium into an intercalation host so I don't know whether there's an inherent issue there but in my opinion people should stop trying to sell magnesium batteries we should understand magnesium calcium has almost the same voltage as lithium so calcium I think is much more interesting but people should do fundamental studies looking at no lithium versus sodium versus potassium magnesium and calcium and that obviously the one material you're talking about gigawatt hour or terawatt hour batteries is look at sodium because there's more sodium around no that it'll be for grid storage not other things the other system obviously if you want high energy density we've got to try to make lithium sulfur work whether it's in a as I suspect a solid electrolyte cell but that's the one with the highest potential energy density um that's good uh so do you want to make common on organic batteries uh organic materials as the electrodes yeah they're going to have very low volumetric energy density so if you're talking about grid storage or something else like that it may be viable we should look at all those things but emphasize again the science and stop peddling it as the next generation battery because then we get expectations in congress that hey you've solved all those problems why do you need more money so be very careful yeah so stay next question there's a tons of questions flowing in right now I think people are excited about the opportunities asking a Nobel laureate you know all type of questions so I um I think this question I will reserve to to you know at the end when we have a kind of panel short panel discussion with Jun this one person asking you prepare for that you know how to win Nobel prize okay I will put on hold on this question now let me ask you the next one uh about the uh more scientific one um it's about an an iron redox involving cathode uh what's your thought about this is it stable if oxygen right and iron and the crystalline lattice participate in the redox reaction and contribute to the cathode capacity so what's your thought about the an iron redox I I think that there's a lot of hype and discussion on this if you go way back when Jean Ruxel normed in France when he was looking at things like lithium in TIS2 and niobium selenides he was saying then most of the redox action was on the sulfur and you've actually looked at the expansion of the lattice lattice expands in the A direction which says the sulfur is getting larger so I think we mustn't you know treat them separately you've got the covalent lattice and the bonding there is the anion that redox is on the anion often as much as on the cation except in very highly ionic systems yeah yeah okay um stand next one also we commonly get is about availability of lithium um you know people often talk about we might be running our lithium or easily mine lithium that's why we start to work on sodium maybe other cation what's your thought about availability of lithium issue right here that that was a question that came up in the 1970s and if you're looking at the United States all the lithium companies the headquarters are all in North Carolina because all the lithium we knew about was mined in North Carolina from hard rock spotting means and things like that all this lithium in South America was discovered much later so I don't think there's really an availability availability issue certainly not for the next 10 or 15 years there may be an issue of how cheap it is to get the lithium out and obviously there's always political issues and it may be the South Americans will say why don't we make the batteries here we've got the lithium we want to make more of the money from the downstream end of things I don't think in the near future and what people say you know 20 years from now we'll be recycling all the old batteries and re reusing that lithium so electric vehicles and other home storage there's no issue but if you're talking about gigawatt hours or terawatt hours grid storage it then may become an issue but the one thing people like about lithium ion batteries are they're portable so even if you look at the large grid storage they're all in trailers and the one in Binghamton the company AES found they can make more money in Ohio so they took the batteries to Ohio so the utilities want flexibility most of the redox systems the organic systems I expected can look a bit like chemical plants they're not mobile so they have that downside yeah I completely agree with you stand on the availability of lithium I don't think that's an issue it's a cost it's no availability issue yeah at all so the next question stand is on this person asking for solid state electrolyte which one is closest to application is it a nasi con type, garnet type, sulfide or polymer solid electrolyte so what's your comment on this different type of solid electrolyte? I think the polymer has only a lead if they can make it stable to a higher cathode potential because it's soft so it may make a better interface mostly nasi cons and mostly in fact the other inorganic ones will react either with the cathode or with the anode so invariably in those cases you're probably going to need a dual electrolyte system which makes it more complicated yeah the solid polymer is used in these alloy cars in paris and indianapolis so it's in use for some specialized applications already so there's some experience there it operates at 70 degrees centigrade which may not be all that good but in some ways it's easier to control the temperature if it's a bit above room temperatures yeah yeah so uh stan people also want to make comment about zinc ion batteries that's going back to low energy density batteries so i know there's some facilities in um cuny in york city whether using it for some smoothing within the engineering building uh obviously um zinc air batteries used as primary cells for hearing aids and things like that and people who made them you know partially reversible as an outfit and i think phoenix doing that so there's challenges there but they're not going to be high energy density so you're not going to put them in your phones or in your cars or anything like that yeah yeah and let me give you maybe uh two last quick questions and the first one is about actual fast charging so what are the ways for doing uh very fast charging let's say you know five minutes well i will just say probably less than 10 minutes like five minutes is very hard less than 15 minutes and why are still maintaining the battery's energy density you know what are the ideas you could do that i think it's going to be extremely difficult it's not just retaining its energy density it's retaining its lifetime even if you do test in the lab if you overcharge or discharge too fast you'll degrade the system so it's going to be a trade-off no you don't think kind of very fast charging and extremely long lifetime yeah okay one last question is about a person asking um the relationship between academia and industry right for academia researchers uh how do they better transfer the basic study into practical application as scale that that's the the big issue and i think you may know the answer there as well as me i think that the problem hit there and we're trying to solve it in new york state is there's really no serious battery manufacturing in the united states so if you want to transfer your idea from the lab to a product you're involved these days have to go to asia and and get their help in doing it so certainly we're trying to get the facility built just a few miles from the university to actually get some manufacturing going on in new york state and building a small facility than a full-scale facility there so i think we've got to get some manufacturing going on and maybe one good thing i'll come out to this covid virus is we got to be more resilient we've got got to do more to manufacturing ourselves we can't have the supply chain from all around the world and then it gets broken yeah well thank you stan i think in the future we'll have i also for audience to know we'll have more of these discussion topic we will also bring in the industry expert into the future symposium so we can discuss this topic more i think the time is up stan thank you very much for sharing with us about the history and the prospect of lithium ion battery thank you thank you um our next speaker is uh dr and professor jin liu from p&l national lab uh jin please come back on yeah i'm on okay i will hand the uh the podium to you thank you okay all right uh thank you uh thank you yi uh thank you for organizing this great event uh it's a great pleasure to follow stan's presentation uh also some pressure uh following a wonderful presentation it's also a great honor to have both stan and the yi and some of our colleagues from stanford university snack to be on the butterfly hundred consortium team so stan today give a very good presentation on what happened in the field of niche ion batteries and some general um comment on the directions uh where we need to go in the future what i'm going to do today is to uh talk about our effort in developing next generation high energy lithium batteries particularly from the perspective from the sort of new program DOE it's not so new now it's three and a half years uh this program is called the battery 500 consortium so as stan mentioned the invention and development of niche ion batteries uh really has fundamentally changed the society uh so without this great technology we will not be doing this video remote conference uh so this is so critical and the Nobel prize in 2019 was now overdue in our opinion one great example of the revolution is the electric vehicles um i think by some estimate uh in the future uh we're probably not going to see every gasoline cars be replaced by electric vehicles but uh probably we can comfortably say 20 to 30 percent or the vehicles can be electric that's a lot because each year we have uh marketed about 100 million cars so uh really uh the electric cars uh not only uh impact energy environment but also change how we uh travel however if we look at the um what's happening today uh the cost of the batteries and some other things still need to be improved for example if we look at the Tesla car I know our friend Yi already on the second Tesla car now uh it's a great car but the batteries if you look at uh right now the battery cost the pack cost slightly less than 200 per kilowatt hour if we want to do the calculation 100 kilowatt hour battery times 200 that's $20,000 right in cost of batteries so it's still a little bit more expensive we want to reduce the cost to half of that so that not only professors from Stanford University can buy the Tesla's but professors from other universities students graduate students can all buy electric cars at the cost of gasoline so that's a big driving force uh in the R&D community now but I don't want to say electric car is the only application of Nissan batteries we know our cell phones personal computers uh all heavily rely on this tiny battery uh in the device on a very small scale uh of course on the transportation side we not only have electric cars we have drones uh we're interested in electrified marine transportation uh electrified aviation then the demand for high energy safe batteries goes even much higher but we're talking about the energy infrastructure uh household energy storage centralized energy storage the battery get bigger and bigger as the uh been discussed a question being asked many other technologies have been evaluated and still the Nissan batteries uh probably are more than 90 percent of this kind of applications and what we would like to do in the future really is to improve the technology today so the energy density can be much higher than what we can do today and therefore the cost can be uh much lower of course without sacrificing the safety and other properties so if we take Nissan batteries today slightly under $200 per kWh if we can do a good job in improving the performance energy density using the right material we hope to reduce the cost to half of that that's the $100 per kWh on the cell level so this is the goal of the department energy if you look at the cost of Nissan batteries starting from just not very uh long ago we were at almost $1,000 per kWh and the cost as I said has dropped drastically to less than $200 per kWh already but the department energy really would like to drive the cost down to less than $100 per kWh we have done a lot of study I will show you some schematics on that we believe the way to do that problem is to go back to Nissan metal end node and then use uh some good high capacity cathode materials such as high nickel AMC materials or sulfur cathode so this is the rationale for this program called the innovation center for battery 500 consortium we are about three and a half year into the program now the goal of the program is really to increase energy density reduce the cost of advanced Nissan batteries beyond what we can achieve in today's Nissan batteries it's a fairly good size big program in the core program we have four national labs and five universities but we only have we also have seeding projects so every about every two years we open up to teams outside the core team they can submit a proposal to DOE joining a seeding project and then we work on it for about a year or so narrow down to the next phase and eventually some of the seeding projects can be incorporated into the core program so we started with 10 seeding projects 15 seeding projects now in the second phase we have 10 seeding projects in addition to that we have an industry advisory board including the three big automobile companies in the US and Tesla and other non-profit organizations and companies so the goal of the program is to increase the special energy of advanced Nissan batteries to way beyond what we can do in Nissan batteries as we said if we say Nissan batteries we can reasonably shoot for 300 watt per kg and then what we would like to do is to increase that up to 500 with good cycling life what we would like to do really is the program is different from a fundamental research program so we are not in here trying to invent as many new electrode materials or many new battery chemistry concepts as much as possible rather we rely on the advances made in the community try to identify the best electrode materials that are already we believe are scalable and manufacturable industry and then we can make this kind of cells without fundamentally change the battery manufacturing infrastructure so we try to overcome the fundamental scientific barriers to extract the maximum capacity in the electrode material on the cell level so it's a great emphasis on the what happens on the cell level the fundamental mechanisms fundamental material phenomena can change from single component to the complex cell system level so the two systems as I said we identified at this time is Nissan unload combined with high nickel AMC system or Nissan unload will suffer that's what we are working on today that doesn't mean we are excluding other battery chemistries as they mature but at this time we don't think other battery chemistries are mature enough let's take for example Nissan air battery really the battery architecture battery in actual material and the refusability all those things are not to the point that we can actually make any reasonable cells to demonstrate how things we can work together so we are focusing on taking at least a very high priority on the AMC system and software system and since this is organized by Stanford I just want to show two photos the photo on the left one was sort of the first meeting on Bertie 500 consortium that that was before we had the program that a few of us including colleagues from Stanford Stan and quite a few people were all joined a meeting uh uh Stanford in one of the classrooms in East building so we kind of dreamed of the program if we would like to have integrated Bertie program in the United States what imagine we should be doing so this is a photo I took uh on the on the day of the discussion some of the ideas most of the ideas I think are still holding true today and the next one again is a important event it's the first quarterly meeting of the Bertie 500 consortium after the White House announced the program again it happened at Stanford snack and you see some of the key people attending this meeting so I want to go through some of the rationales homework we did together with the Department of Energy how we come down to this path I want to remind you this chart was derived from chart initially from Argonne and then DOE revised it and then over the years I have been revised it many of these cycles are for schematic only it's not drawn exactly to precise numbers but nevertheless it gives the sort of the ideas on where we can go so in the sort of the left center of the chart we show the most of the data on the traditional DCI batteries in terms of the specific energy this is a graphymetric energy density and energy density of only metric energy density so we can look at the graphite in force fade it's a very reliable material but it has limited energy density in both volume and weight and then there's a traditional AMC333 with graphite but if we take good AMC material with high nickel content and push it with good anode material including good graphite and silicon anode we may be able to get to about 300 watt hour per kg in large commercial cells and then the watt hour energy is also indicated there and there's a sort of little bit outline of the DCI this is carbon oxide as I mentioned that's still being used in our cell phones that chemistry is very unique it doesn't have the kind of high graphymetric or specific energy as we design but it has good bonymetric energy density the size matters so that's why it's still the dominant chemistry for cell phones and devices like that however when we talk about electric cars we want to do much better in specific energy density we did a lot of calculation that two chemistry can potentially do that one is AMC high nickel AMC system with initial anode each other one is mission software mission software would have could have much higher specific energy density but the AMC system may have advantage in bonymetric energy density so those are the sort of rationales we want to do and I also put down other chemistries because people ask about that the sodium magnesium zinc and the redox other battery chemistries these are sort of achievable numbers so all those are much less than what we can do even the most basic lithium batteries but there are great value in doing those fundamental study in those systems because they may have application for large scale very large scale application and also we may have breakthroughs in the electrical material in the future that can fundamentally change the picture but at this time I totally agree with Stan that fundamental research in those areas are important but they cannot be pitched as replacement for lithium batteries now this is a slightly outdated calculation of what we can sort of practically do with lithium metal if we change the materials parameter what happens to the specific energy this kind of top-down calculation is very very important because it essentially tells us exactly what we need to do in each step so if we start with a traditional lithium battery configuration and then replace the graphite anode with lithium metal in a good cell design we roughly get 300 watt per kg now from there is all what we need to push the limit of the material because when we change the separate parameters we put a much higher demand on the material since become much tougher so the things we need to do is to reduce the amount of the electrolyte reduce the porosity of the cathode material increase the cathode loading increase the cathode thickness and increase the utilization of the cathode capacity to more than 220 millimeter per gram and we also need to very significantly reduce the amount of inactive materials like aluminum copper separator additives even the packaging material so the calculation shows that if we really do a good job on all these things we can get to on the paper it's an up limit right close to 500 watt hour per kg but that doesn't mean we can easily do that in a real cell if we want to do that we need to really carefully consider all the fact that in fact not only the materials property but also cell level energy now if we want to get to really get to 500 watt hour per kg or even higher we need the invention in new cathode material or we need to use cathode materials in cathode and like a software and other cathode materials so to make things work under this consortium we have defined three research trusts all the way from materials to cell level but these trusts are not separate ever they have to be highly integrated so the first trust area is called the materials interface and we have a number of scientists in this and Stan is the trust leader for that but just the material level effort is not enough that has to be translated to the desired inactive architecture and the challenge for this trust is to really increase the inactive thickness particularly the cathode and maximize the materials utilization and and also include the solid electrolyte membranes to stabilize the niche metal anode and the last one is a very important one is a cell integration fabrication diagnosis so everything will work on materials and electrode if it doesn't work on the cell level then we don't accomplish the goal so so this is a sort of highly integrated approach that enables us to make real progress I just want to reintegrate what Stan said about the materials utilization right now in these iron batteries we are up to about 25 percent of the theoretical capacity we can of the cathode material we can realize in the real cell what do we believe if we do everything right under our program using these metal anode we may be able to go up to about 50 percent utilization of the cathode capacity in a full cell system so if we do that then even for AM system that put us above 400 watt per kg sort of domain in the next few slides I just want to give you some highlights on what we have been accomplishing in the last three years and then I'll tell you where we are today so in the first stress area the materials interfaces the example I want to give include one on the cathode material Stan already talked about this a little bit in the cathode material we need to be able to maximize the optimize the intrinsic property of the cathode material so that we can use the highest capacity possible of the cathode so the two areas that limit us on the just on the material side one is what Stan talked about is the first cycle loss there are many reasons for that to happen the other one is the gradual degradation of the capacity when we have non-cycles so the team made no effort not only in developing synthetic effort in making our uncathode material for the AM system like a 622811 but also studying commercially supplied material to understand what causes the first cycle loss or the capacity loss of non-cycling so the lesson we have been learning is that most of these losses could be related to phenomena happening as electrolyte cathode interfaces the surface initiated reaction cause internal phase transition micro cracking dissolution and enemy to reach this reform dissolution from the castle to the anode so we believe all this phenomenon can be reduced by proper surface treatment optimization of the surface chemistry the example shown here is from Stan's group that we can have use niobium oxide coating to prevent the first cycle loss and otherwise from Texas use your organic polymer coating to stabilize the non-cycling stability of the castle material another very important effort on the materials and interface is developing electrolyte so one of the sort of key limitation in the cell level chemistry is the reactivity of the lithium metal towards anything including the electrolyte so the team particularly led by scientists at PEO made a tremendous effort to develop many generations as I shown here I'm not going to go through the details to new electrolyte chemistry new formulation and improvement of such electrolyte so the main effort in this are focused on couple things one increase the columbic efficiency of the electrolyte for niche metal deposition and stripping if we get want to get reasonable cycling life it has to be way more than 99 percent the other one is to improve the voltage window improve the temperature window reduce the viscosity and the number since as you can see here this is really aerial made a lot of progress and some example shown here is that if you have a poor electrolyte you have deposit niche metal with very poor structure and more CSEI layer if you have a good electrolyte then you really begin to change that in a fundamental way and you begin to develop much denser niche metal deposition layer so those are examples from the material level going to the next level to the electrode in order for us as I said to increase the energy density we need to increase the cathode sickness from what we do normally 40 micron 50 micron to more than 100 micron now this has to be very dense too right we cannot have a lot of porosity a lot of additives in this so the additive has to be less than much less than a few percent and the porosity need to be less than 25 percent so this is very difficult if we do that even the material level holds up the electrolyte cannot penetrate the thick electrode and the mechanical property become problem there's an expansion that all will prevent this good electrode material from working properly in a real cell so we have done a lot of very detailed characterization what happens if you have a thick electrode so if you have a thick electrode not only are from the top of the electrode to the bottom electrode the chemistry can be different you only use the electro material at the top not the bottom we have in situ x-ray that we can do spatially resolve the characterization to prove that we also have an even electrochemical reaction across the width of the samples we show some of the pinholes in this that can cause the electrode to fail in a real cell so we the team has done a lot of work try to overcome this kind of problem a lot of time we think it's just engineering problem but it's actually a lot of good science into this by this time we show that even with almost 200 micron thickness on the electrode level we can still cycle the electrode reasonably but in real cells maybe we don't actually need to go to that high thickness so we are making good progress on that and another very very important thing is the fundamental understanding of the failure mechanism in real cells not just the idealized not I just idealized the situations I'm just getting out of jumping out of myself but in this case we have a lot of wonderful results from Stanford and UCSD use developing a lot of new tools particularly in situ characterization tools and also pioneer work in cry TEM in the first high resolution TEM characterization of the SEI layer of the dendrite structure also the first effort to understand really what happens to the niche metal how much is metallic niche metal failure how much is really the SEI reaction those quantification of those is very very difficult and they have been more effort in our team to characterize that and the final lesson is that the reaction of the niche metal cause isolated dead niche that cause a large part of the cell failure so let me go back to some important work to prevent the niche metal from reacting with the electrolyte not only in terms of better electrolyte but also in terms of solid electrolyte that can protect the niche metal the two approaches who have been found in one is Ponymer Ponymer compulsive material shown here from Stanford the other one is a pure ceramic or glassy sony the electrolyte from Texas professor John Goodenough's group so this we we have not to the point that this has been implemented in the cell but if we are very hopeful that will happen pretty soon and then that will really bring a very significant breakthrough in the field now on the cell level I think people ask the gap between industry and academic research so what we have realized is how serious this problem is because on the cell level a lot of things are constrained not free for example just a cycling knife can change drastically depending on the experimental conditions as we shown here with the niche metal if you have different amount of electrolyte different niche thickness different cathode thickness all changes so you cannot really say claim how much improvement I have made so the better 500 consortium really develop a requirement the standard protocols that we need to use when we benchmark our material if we say this is good what is good so we have standard testing conditions that we use to prove that if we do that the coin cell results can be a good indicator what what happens in a real pouch cell if we don't do that then there's no collection and still other things many other things matters including safety how we test the real pouch cells the effect of pressure that many many other things that our team has been making tremendous effort to optimize but anyway I think the proof of what we have been doing in the last few years is this one so we have the progress on component in actual in actual light and niche metal all the things now we need to put this together to see how it will work so in this chart we started in 2017 in a real pouch cell at that time we could do 50 cycles so I would challenge the community today for many of the publications literature today if you took take the recipes published in the literature make a pouch cell real pouch cell test them it probably is going to be less than 100 cycles even today so after three and a half years we have made tremendous progress for 350 watt hour a package cells now we can cycle stably way over 350 cycles so this is the true proof of the strategy we're developing we demonstrate that it works of course I don't want to claim that we have solved the problem because the even we can cycle three to 500 cycles we're still concerned about the safety and many other things that need still need the fundamental solution and we can do much higher than 350 but 350 give us a good platform to understand the fundamental phenomenon so here we show the results of 400 watt hour per kg another thing I want to show you is that even we do about 2 amp hour cell if we make it bigger 350 become more than 400 and we can optimize if we replace 622 with 811 increase the thickness there's still room to improve even on the AMC systems so this really shows the potential of this approach now people ask sony state batteries and I want to just benchmark little bit this is from paper from Germany all the data they dig out for sony batteries now there are many many fundamental issues in terms of the interface is other things so if you look at this one thing is it's just not enough to have a sony electrolyte you need to put them to work in a real cell not only work on the interface but also get the right configuration you know all most of the data published even on the conceptual levels you can see there are way below what we can achieve with the kind of cell design that we are working on the battery 500 consortium today so in summary I think for next generation batteries we are making good progress we also believe what we are doing probably I would claim is the most feasible and promising approach towards something that's better than today's niche iron batteries but we are not done we still have much work to do in solving the niche metal problem that really requires the integration of material scientists like us with battery experts like Stan with engineers manufacturers and the whole community need to work together but just working on material level will not solve the problem so that's sort of the end of my presentation I want to end with the same note as Stan ended that niche iron battery has revolutionized how we work and live and the revolution continues and many many other innovations will come along and we are in a very very special period now with the coronavirus even under this circumstance we can think very hard how what we can do can improve how we live our life how we the quality of work even in a very difficult time all right thank you very much I'll stop here well thank you very much Jin for giving a great overview on what's happening in battery 500 and the key problems you would like to address so there are a number of questions again of very long leads from the audience I will pick some to ask you the first one is about lithium metal anode this can do can you can have anode free of lithium metal batteries starting from no lithium metal lithium come from cathode what's your thought about this not having lithium foil in there but having just a current collective to have anode free batteries yeah this is a very interesting problem that I think many groups started not just today but also in the past even in recent years ppnl published a number of papers and jeff dan has published a few papers very recently and then the korean group published the the kabe anode with all Sony the battery design sort of all Sony battery design so I think it's a very important direction particularly for understanding what happens on both the castle side and the dino side in essentially when we have a lithium metal we have access to lithium in the system to have us to achieve much longer cycling life but without the lithium metal if for example you just have the copper foil in the anode then what are you doing is essentially you're stripping the lithium from the castle and deposit on the anode and then you strip back and forth now the stability of the anode is a very significant problem in that case right you don't have anything on the anode problem but another thing I really I have debated with people I people should think about so the anode free only exists at the beginning of this testing as soon as you begin to sell a cycle the cells there's no anode free anymore because let's say you have a traditional lithium batteries lithium batteries even the castle capacity is four millimeter per cm square you essentially have a equipment of 20 micron lithium on the castle right if you in the first charge discharge cycle if you move all the lithium from the castle to the anode that's what you want to if you want to use the full capacity of the castle right you move all the lithium then you get a 20 micron lithium metal on the anode that's not different then from the second cycle on you then you start with 20 micron lithium right so actually anode free doesn't make the problem go away it just probably I think it's an ideal system to study some phenomenon but it's extremely challenging yeah Jun I agree with you I think anode free should be for a benefit or doing anode free at the end you still have lithium metal coming back to the anode right so so next question what are the most important steps for lithium sulfur batteries to to get it to work we know lithium sulfur is challenging both you and I work on this for a long decade right now just outstanding scientists out there working on this problem for a long time so what are the most important steps for lithium sulfur to work so lithium sulfur is very important I didn't have chance to talk about it today it's still a big effort in our program and it's a little bit more complicated in the AMC system because in that case the castle there is also a convection reaction right so for lithium sulfur because of high capacity of sulfur we can indeed make high energy cells has been as been reported demonstrated in the natural literature however the cycling has been much worse than what we can do in the AMC systems in that case I think what people have been discussing the literature there have been a lot of effort in trying to understand the dissonotation and shortening of the pony sulfide and those have been in the literature attributed to the main cause of problem of lithium sulfur batteries but what I really believe the challenge actually should be shifted more to the castle side that what's the ideal castle architecture what are the ways to reduce the carbon in the castle reduce the porosity of the castle while at the same time maintain the stability of the castle I think people should really spend much more time on the electrode architecture yeah so Jin there are many questions you know ranging from one to ask you what's the you know silicon annual for massive market and what's the liquid and solid electrolyte comparison where the liquid electrolyte lithium metal can go about 99.8 kW efficiency I think there's many questions right there for the time consideration why don't I propose we do this I think all this question normally for you for Stan it's also for the whole field of battery researchers Stan can you can I bring you back up to the this final we have about seven minutes I think we'll need to end today's symposium but I do want to take my executive role right here as a moderator to ask you some really interesting questions I meant to ask both of you I will separate these two questions one for Jin one for Stan right Jun if you don't mind I come back to Stan sure Stan when the Nobel Prize was announced I was in Germany in the same conference as you and I was taking the flight back to San Francisco I predicted remember before it was announced I said Stan you're going to win it this year I told you about I told you about it and then you won right so and then I thought about this I think there's a lot of young students in the audience right there I want to ask you I really like Steve Jobs you know speech commencement speech at Stan for 2005 I think he's saying life is about connecting the dots there's many things you cannot really plan it just when you plan that dots right there you look back you say they are all connected so your journey of working on electrochemistry working on batteries this long journey right there what what's your thought you can share with young students and in career developments you know it's any wisdoms you can come back and share can you really predict what's down the road and what is it about your life journey I think it's difficult to predict what's going to happen in the future but as I said when I went to Exxon they were very interested in becoming the Bell Labs of the energy industry they wanted to make electric vehicles they perceived that oil was going to run out at some point so we had this vision of going to electric cars back in the 1970s and one always has this vision of having a big impact and the scientists you like to have a big impact but you can never predict what's going to happen and you certainly can't predict what's going to happen with Nobel Prizes you know we were told in 2015 that John and I were favourites to win it then by Reuters I think so both universities talked to each other planned everything nothing happened nothing happened the next year in 2019 they didn't plan anything I know at least the minute they announced it you still couldn't predict it right the minute before they announced it well as you know they they called me up I think 30 minutes before the public announcement yeah and they found me in Germany at that time very good well thank you for sharing now Jun coming back to you well I certainly are very familiar with your career path about a decade let's say 15 years ago Jun you didn't work on batteries at all right you will you become known for something else and then you move into energy storage so what's your thought you can share with students or young faculties your career path to give them some advice so well this is a very uh a company question but I can sort of talk about two things one I think what happened to my career is I know I'm not an expert on a lot of things including batteries so you and I started working on batteries about the same time probably but I think the best thing I did or I tried to do was to learn from the best in the field really understand what people are thinking about ask them to teach us uh the lessons in the uh research also the perception and the opinion in battery research so when we started the the battery research program at the time we had a zero dollar zero people right we hired a number of people uh uh uh later on started the program but one of the best thing we did was to invite some of the best experts in batteries including Stan he come to PNG a few times and we recruited the one of his student Ji Xiao and many other people including yourself Yi you have been a greater innovator not only in battery research but in all other areas so I learned from all the people around us and then work with the best people in the community so I think this is probably the best effort I made and it has helped not only my career but it has been helping the community another thing I want to share is we really need to understand uh why we're doing certain things not only in terms of technology application but also in terms of science so uh it's not just to make ourselves more famous rich or more better reputation not only those those of if you do good work those things come along like Stan who eventually even much uh delayed but receives the Nobel Prize right you cannot have those things as a goal but uh I think my life's lesson is really try to make a difference in people's life try to make not only myself feel better make people around us feel better do better work and be able to really communicate on when we are doing certain things so one of the things I keep on telling our young staff or young scientists is that we need to explain our science or explain our technology to my mother-in-law in five minutes if we cannot do that uh there may be some problem anyway I'll stop here I think uh Jindish is a very good concluding remark right there we are here working on energy storage is trying to help solving the world problem thank you very much well at the end uh Justin can you bring up the slide um and uh I would like to just make a concluding remark first of all thank you both Stan and Jind for giving just wonderful lectures right here and answering many many questions uh these will continue into the field now this uh naturally to our next week's symposium also two very outstanding scientists in the battlefield Dr. Cal Amin at Argonne National Lab and professor Peter Bruce from University of Oxford I please notice the time it it will be Friday instead of first day May 29th the same time 7 a.m California time so it will be you know afternoon in Europe and the evening in Asia I look forward to seeing everybody and next week's event this will continue as a weekly online symposium we try to bring the best speakers to interact with the the whole world the whole research community at the end thank you very much I'll see you next week