Battery Capacity testers
I make a commission for purchases made with the links below
After testing multiple battery capacity testers and blowing up a few (see below), this one has survived. I have used it to accurately test a multitude of various batteries and I love it!
The biggest downside is that you need to add your own wires and load. I usually connect an inverter and it works great.
When your batteries BMS cuts off power to this unit, it has a memory and will save the results of your test. That means you do not need to worry about being present when the test is over.
And its cheap! Under $15
Click here for a cheap price
I was scared to try these at first, but they rock! Dead simple and great tool for beginners to test the capacity of their individual cells or entire battery bank. Only downside is that it can only pull 15-22 amps max (185 watts), but it works well. It has high and low voltage disconnect settings for protection on single cell tests, and you can change the current to whatever you please.
Update: I destroyed mine when testing a higher voltage battery and pushing the current too high. Keep the current low when using this, and do not test batteries above 24V.
Click Here for the aliexpress listing