Is this simply measuring voltage with no load and mapping that to a percentage?
50LF 12V 24V 48V Digital Battery Capacity Display Universal LCD Car Motorcycle Lead acid Lithium Battery Monitor Voltmeter|Battery Testers| - AliExpress
or is this one is performing a real load test?
2019 Newest Bluetooth 12v Battery Monitor Car Battery Analyzer Test For Android Ios Phone Free Shipping - Diagnostic Tools - AliExpress
50LF 12V 24V 48V Digital Battery Capacity Display Universal LCD Car Motorcycle Lead acid Lithium Battery Monitor Voltmeter|Battery Testers| - AliExpress
or is this one is performing a real load test?
2019 Newest Bluetooth 12v Battery Monitor Car Battery Analyzer Test For Android Ios Phone Free Shipping - Diagnostic Tools - AliExpress