How to begin checking batteries

C

cesarbg

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I have around 200 laptop batteries that I have to pry open and extract the batteries. Id like to create small rechargeable batteries (enough to power lamps, mostly) and charge them via solar panels.

But first Id like to know how to check if the batteries are good or not, and how to charge them, preferably if it is possible to charge them in bulk or after they have been wired.

Im new to the diy world, but im eager to learn, so, all info is appreciated.
 
Most of us are using these chargers
http://amzn.to/2keun9Q

My workflow
1) Remove battery from pack
2) Check battery with voltmeter, if less than 2.00v, place in separate bin for further processing later
3) Place battery in the discharge tester using the "Charge Test" cycle. The battery will charge, discharge, then charge back up. The capacity will be reported from the discharge cycle.
4) If battery is less than 2000mAh, discard
5) Let battery sit for 1-2 weeks. Recheck voltage. If voltage is greater than 4.10v, use for building packs.

Those 200 batteries will give about 1800 cells. I would pick up a couple of chargers. You'll get through them pretty fast :)
 
This is how I do it:

image_ynbbdb.jpg


More info :http://diytechandrepairs.nu/current-solar-layout/ orhttps://steemit.com/powerwall/@diytechandrepair/how-to-process-lithium-18650-cells
 
Cesarbg-DONT discard the under 2000mAh cells, they are still good. I follow Daromers flow chart. :)
 
Emike said:
Most of us are using these chargers
http://amzn.to/2keun9Q

My workflow
1) Remove battery from pack
2) Check battery with voltmeter, if less than 2.00v, place in separate bin for further processing later
3) Place battery in the discharge tester using the "Charge Test" cycle. The battery will charge, discharge, then charge back up. The capacity will be reported from the discharge cycle.
4) If battery is less than 2000mAh, discard
5) Let battery sit for 1-2 weeks. Recheck voltage. If voltage is greater than 4.10v, use for building packs.

Those 200 batteries will give about 1800 cells. I would pick up a couple of chargers. You'll get through them pretty fast :)
Click to expand...
Thanks, I just bought one Opus online. It should take some time to get to me, since it will come from China.
I was wondering if the Nitecore D2 or similar models will also work, as I can get my hands on them faster.
Thanks!

daromer said:
This is how I do it:

image_ynbbdb.jpg


More info :http://diytechandrepairs.nu/current-solar-layout/ orhttps://steemit.com/powerwall/@diytechandrepair/how-to-process-lithium-18650-cells
Click to expand...

Thanks for this flowchart, it is quite clear to follow.
 
daromer said:
This is how I do it:
Click to expand...


Thank you for your contributions for us new people. My question is regarding the initial cycling for the cell (capacity check). If I find a cell that is above 1v, I have beencharging it to 4.2v and then let it sit for 1-2 weeks to assess for a drop in voltage (self discharge). My thoughts at first were why waste time on cycling a cell that I'm going to discard anyways due to self discharge. Am I wrong here? Do you think its better to cycle a cell first, and does this help revive it better than just charging it?
 
Not many cells self discharge and to keep the flow simple I do it this way.


If it revives by cycling im not sure of. Some people have "seen" it but I havent and the data papers says otherwise.
 
Also, just because a cell is near 1V, or even below, doesn't mean it's bad. There have been many cases throughout the forums where people revived hundreds (cumulatively) of cell at or below 1V and returned 1800+mAH cells. And many have found 2200mAh or better.
So, just because it's low, doesn't mean it's bad. If you buy a car, and the gas tank is empty, is it a dead car, or does it just need a little cycling/filling up to get it going again? ;)
 
Cant compare it to a gastank on a car though... If the gas tank on the car is empty nothing is happening to the car.. It doesnt rust faster... Meanwhile in the battery there is a chemical change happening when woltage gets low. This can potentially harm the battery in such a way that it causes issues when charged.
This is one of the reasons BMS boards shuts down and wont start again on several things.
 
true, good point
 
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