john61ct said:
Cell count alone does not help.
Unless you mean at 1S voltage?
Are they LFP at 3.2Vnominal,
or the 3.6-3.7V li-ion type?
If at a higher voltage, do you need a balancing charger, or will you use other circuitry to handle that?
what is the series count?
e.g. 16S LFP is 48Vnom, 7S li-ion is 24V
Do you need adjustability for different use cases, gentle normal cycling vs stressful benchmark testing?
Then, what C-rate, stressful fast charge
or is gentle/slow OK? Do you also need that to be adjustable?
What input voltage, AC grid power or lower voltage DC?
Willing to roll the dice on cheap chinese only a few hundred bucks?
Or looking for a quality western unit more likely to be reliable for hundreds of charge cycles?
Does it need to be new or is eBay OK?
hey thanks for the reply, my mistake for not providing enough info. I'll do that below.
I need charger for 1S. I will be charging and discharging the cells independently to see the capacity of each. I am planning to do a couple builds for me and my friends, and dont want bad cells to be added to the battery. I already have an IR tester, but no capacity measuring device.
I cannot use the normal capacity testers available in the market as of now as the max I have seen are 5 cells at a time. I will be testing 4000+ cells and even if I buy like 10 of these capacity testers, it'll just not be worth the time. Is there a faster way to test the batteries capacity before I spot weld them together?
also, what are the downsides of just using the cells without testing them for their capacity? From my understanding, the capacity of the whole pack in decided by the cell with the lowest storage. And if the difference is too high then the parallel cells might start charging the empty cell and cause a potential short! I want to avoid that at ANY cost.
- NMC 21700 cells,
- Gentle cycling is fine, but i need the faster solution, if stressful is faster, i'll prefer that.
- 1C charge and discharge is fine, as I need to measure the capacity only.
- AC grid power 220V preferred. Fine with DC too. Industrial grade 380V AC can also be arranged.
- New or old device both are fine.
- Chinese or western, both are fine as long as they are reputed and have a decent service life.
Hope I answered everything. What are my options?