If your needing to check battery capacity plus charge cells then I would recommend a hobby charger.
Most, even the cheaper ones, can do a 3 to 5 amp discharge test.
I use a icharger 208b but this is a little on the expensive side just for general purpose capacity test.
I’m not up to date on exactly what plug in chargers are capable of at the moment. I’m sure they are a few members who could chime in, and recommend one. I’m old school, and the hobby charger is still the most versatile when it comes to running discharge test in my opinion.
A decent one can be had for about the same price as some of the plug in chargers. Some hobby chargers are capable of data logging using logview (software). Out puts a graph similar to HKJ’s graphs that can be saved and used in post.
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There is a bit of a learning curve though and not for everyone, but if your becoming more serious about testing batteries to share your findings or just your own personal use, I think its the next best step up. :smiley:
Here’s a old log file I had saved on imgur. It’s a AA duracell (rewraped eneloop) at a 3amp discharge.