Pack one was well used and a couple of years old. It contained 6 light purple cells marked CGP18650 E. Two of the cells voltage was 1.5v. the other 4 cells measured 2.49v. These pack has been sitting uncharged for 8-12 months,…should I keep them or trash them?
Pack two was an unopened new pack, office lady ordered wrong pack and never returned it said I could have it! :bigsmile: It contained 6 pink unmarked cells, there voltage ranged from 3.88v-3.93v,…I was surprised the voltage was so high as this pack has been in a desk draw for almost a year. All 6 are currently on charge but I would like to know more about the cells.
I’ve pulled many old battery packs, most times you will find 2 cells below 2v
You can charge them up but in my experience their capacity is around 800mAh or less , the 2.49V cells might come back and provide a reasonable capacity of 1200mAh, which is fine , but you will always have doubts.
Most cells from a laptop pull are around 2200mAh rating, so is it worth it to keep used cells between 1000-1400 mAh? I do use them so for me it’s a worthwhile exercise, besides I enjoy fiddling with the whole process.
It’s also a good way to learn about older cells and their behavior as long as you have the correct equipment to monitor charge / discharge conditions accurately.
You need to know that if the temperature rises suddenly on a old cell during a charge or discharge, it’s time to pull the plug and toss it fast.