 How many people know about the benefits of rechargeable 9 volt batteries? Hey, what's happening? NJRoot22.com here with another Tech Tip Vlog. And for anyone that doesn't already know, rechargeable batteries have come a long way in the past few decades. Back in the day, all rechargeable batteries were pretty much nickel cadmium. They were awful batteries. They were comparable for high drain devices and suffered from what they call the memory effect, which they totally forgot how much juice they had. The new standard for most rechargeable batteries is nickel metal hydride, NIMH. They have excellent capacity with no memory effect and they can be used hundreds of times and pay for themselves many times over. While we use nickel metal hydride batteries in mostly the AA and AAA formats, we never gave much thought to 9 volt batteries until recently. Now there are two kinds of 9 volt rechargeable batteries that you need to know about. You have nickel metal hydride and lithium ion rechargeable. Now just as a comparison here, most cell phones and laptop batteries use lithium ion batteries because they offer a stable voltage throughout the discharging process, whereas nickel metal hydride batteries, the voltage goes down as they lose charge. Now when it comes to 9 volt batteries, most applications are smoke detectors, tools and toys. We recommend getting both kinds of rechargeable 9 volt batteries, the nickel metal hydride and the lithium ion. And try them out in all your applications. See which ones give you the proper life because some apparently work better in some devices than others. But none of these can really outlast the standard alkaline battery from what we've seen. And also they have the super duper lithium ion non-rechargeable batteries as well. Some of them can last 10 years in a smoke detector. But the money saved for these rechargeable batteries is not a bad idea. You may want to use those long lasting batteries in locations that are out of reach. Lastly, it's essential to note that the various 9 volt batteries must be charged in their designated charger, otherwise you will run into a major risk of fire or even explosion. You can see this little chart here came with one of my recent purchases and it tells you clearly that you can't charge really any other battery. So that's it. If you haven't given 9 volt rechargeable batteries a whirl, it's worth looking into as we all don't mind saving a few extra bucks each year. If you like this video, please hit the bell and subscribe and I'll see you next time.