Laptop run off of AA batteries

The red multimeter is displaying amps and the yellow multimeter is displaying volts of the battery pack. Here I was using 11 AA batteries. Using between 10 and 12 cells worked because those were the voltages in which the inverter would not shutdown. The I got a total of at least 30 minutes of run time from one set of batteries. 8 of the cells were new 2500mah nimh cells and the others were 2000mah nimh. I tried to use 1000mah nicd cells, but the voltage would drop below 1 volt per cell. The larger capacity of nimh cells outweighed the higher "c" rate of the nicd cells in terms of over all output wattage of each cell.

The highest power draw that I had seen was about 3.5 amps when playing Need for Speed. According to the computer, the power usage was between 15 watts and 30 watts. The inverter was a 400w black and decker model. The trick to the whole experiment was to make sure the laptop wasn't charging its internal battery, which would of made the power draw to be around 50-60 watts, way too much for AA batteries.

I tried this once with an old compaq laptop by directly wiring the cells to the power port. This required about 30 cells, which meant some of the cell's voltages must have been near 0.

Category:

Science & Technology

Tags:

• AA
• battery
• laptop
• power
• inverter
• experiment
• run
• powered
• multimeter
• awesome
• computer

[onexrocks]

yeah why couldn't you just skip a step and add up batteries to the proper voltage of your laptop (mine would be 19.5v) ? and would it be possible to recharge your external batteries off your laptop power supply!? you know if it gives out lets say 19.5v that should be able to recharge the entire set of batteries to 19.5??

[MrPizzaman09]

@onexrocks You could, but going through the inverter allows for an extra layer of protection due to low voltage. And yes, you could charge the batteries with the power supply (I have done this many times when I don't have a proper charger). For this case though, I wanted to use the batteries like a buffer. Also, my solar panel only likes to output efficiently at 12v, so going to 19v wouldn't work as well, but it could be done.

[Rockflier]

Nice! Good job

[sirmasterpimp]

Pretty cool, I did this once with a 70 watt power inverter and single 1ah rechargeable 12 volt nickle cad battery......surprisingly I got only about 5 min out of it (battery was 5 years old and deteriorating). It would be cool if laptops came with the option of user replaceable cells so people wouldn't have to spend $100+ on a new battery. 5 stars

[MrPizzaman09]

@killzpwnz0red I looked at the website you gave me, and it says the laptop only pulled between 0.5 to 0.8 amps @ 12v. My set up was using between 2 - 3 amps, sometimes spiking as high as 3.4 while playing a game.

[MrPizzaman09]

@killzpwnz0red Yeah, you could do that with the small laptop, as long as the laptop doesn't pull too much power. Ideally, you want to have a buffer in their so your voltages don't spike or drop too low. I also noticed that the eee pc's use a 7.4v battery, so power usage must be low.

[killzpwnz0red]

@MrPizzaman09 The small asus eee pc and the acer aspire one will run from 10 rechargable AA batteris as well as any 12v source including AAA battery pack.

See voltsxamps (dot com) and you will see how it is done very easily.

I was able to run the asus netbook right off a 15 watt solar panel without any batteries attached to the netbook. Check out the url above and you will see.

[imback218]

@MrPizzaman09 ook thanks for the advice :)

[MrPizzaman09]

@imback218 Volts and amps. You all ready told me 20 AA cells = 24v.

I would imagine any battery would be enough power for a 10 minute run time. You could pull up to about 10 amps from a 3ah nihm AA battery, so you would have about 240 watts of power, which should be plenty.

[imback218]

@MrPizzaman09 10 minutes..and what do you mean how much power am i drawing?

[MrPizzaman09]

@imback218 How long does it have to run? And how much power are you drawing?

[imback218]

@MrPizzaman09 no i dont, sorry