big lithium ion battery pack made from used laptop batteries (190+ watt hours) - lithium batteries for sale
I bought 10 large used laptop batteries for only $8.
I was able to make a 190 watt hour battery pack very easily.
Turn on the battery first and remove the battery.
You can open the plastic box with a flat head screwdriver.
A little bit of a saw angle helps the screwdriver enter.
Keep the cells of the parallel group together.
Measure the voltage and write it on the package.
Battery is arranged by voltage, less. 5, .
More than 5 to 3 and 3.
I charge with the cheap transformer I can find.
This is very dangerous because you can charge the battery.
Don't charge the battery before 4. 2V.
If the battery is less than 3 volts, you need to charge the battery at a low current of less than 50 mA.
The walkie-talkie I use, usually 3 AAA batteries per charge.
Charge to 3 volts and switch to high current.
After 3 volts, you can charge up to 1A per battery.
I use a 12 volt 4 amp charger and charge 3 batteries on the series. Cell under .
There are often problems.
The lithium battery is great, but you have to stay between 3 and 4 volts.
When you build a package, arrange the battery in parallel and in series to get the amps and volts you need.
Most laptops have 2200 mAH batteries that discharge safely to 1C (2. 1 hour 2A).
I have 3 sets of 8 parallel units in series for my package.
So my voltage is 12 to 9 and the maximum current is 17. 6Amps.
This works well for cheap 12 V cars.
If you want more power, you can add another series and get 16 to 12 volts.
It is important that each tandem set has the same number of parallel units.
First put your cells together in parallel sets.
Then tape these suits together, alternating the front up and down, and tape them together.
I connected the package with a small nail.
Cut off the nail head, polish it and the top of the cell and weld the DingTalk to the package.
I put 4 cells together from the bag.
When welding on the front, it is very important not to weld on the side of the top of the battery.
The outside of the battery is negative, so the battery will be short-circuited.
I also welded 2 14 gauge wires on the front and back of the battery.
I stuck the wire so the battery couldn't pull.
I stuck some fiber cardboard together to make a box.
I folded some padded fabric and put it on the bottom of the box.
I hit the battery with fabric and put it in the box.
I stuffed more fabric in the corner so the battery was safe.
This fabric helps reduce impact and vibration, but the battery gets too hot due to insulation.
I would like to be able to measure each set of parallel batteries without taking the battery out of the box.
The first group can be measured using negative wires and top of the battery.
The last group can be measured with a positive line and a small hole in the battery plastic.
You can put a prob in this hole to measure the negative value.
If you measure the total voltage, minus the two batteries, you get the intermediate voltage.
I installed the battery on my prop bike and it worked great.