Explanation battery test report:
Guidelines for testing e-bike batteries
1. Check the internal resistance (Ri), normally 0.1 ohm until 0.3 ohm. Possible causes when
this is higher than 0.4 ohm:
Battery is broken, reduced capacity, failure in case of mountain tours;
Current is set too high for type of battery, reduce current;
Bad connection between battery and tester, check cable and connectors.
2. Check Uopen, the open clamping current has to reach the load current, normally 0.2V to
1V lower. When lower, leave the battery for 4 hours and charge again. Possible causes
when this is lower:
Battery is not fully loaded;
Charger is broken;
Battery is broken, reduced capacity (for example because of an imbalance in cells).
3. Check Umin. This is the battery current just before end of test. One can determine from
this whether the battery has been fully discharged, normally approx. 0.72 x charge
current. When this is too high the battery has not been fully discharged. Possible causes:
Discharge current is set too high by which the battery thermally turns off, turn the select
button to restart the test (reduce discharge current);
Cable between battery and tester is disconnected, check cable and restart test;
Battery is broken, reduced capacity (bad cells because of which BMS turns off).
4. Check the capacity: Ah and Wh and compare these with the battery specifications.
When the percentage is lower than 70%, the battery has been ‘economically’
depreciated.