Review on USB Load Tester - Adjustable Constant Current Electronic Load Battery Capacity Tester Module, 150W 200V 20A Electronic Load Tester by Ronald Noel

I have used it to test single 3.2v lifpo4 batteries as well as 12v and 24v batteries I have also used it on regular and deep cycle car batteries. It has limits on how much it can draw and this can make the tests take a while and you'll get happier results with just 0.1C batteries than full 1C). I used the BMS and ammeter to check the current drawn and found it to be 100mA on average. This is close enough for all normal testing. I recommend it.