Hi team,
When customer doing EC 62368-1 M.4.2 high temperature charging test, the battery did not immediately stop charging when it exceeded the maximum charging temperature declared by the manufacturer 40 degrees. (It stopped at 53.1 degrees)
The NTC on their PCB is SEMITEC 103AT-4B (10Kohm @25℃), and its temperature impedance specification is consistent with recommendation NTC Mitsubishi TH05-3H103F.
We think it should be "disable charge when the battery temperature outside of the 0°C and 45°C operating temperature window" just as what be shown in D/S.
Here're 2 questions:
1. Why does it stop charging at 53.1℃ not 40℃?
2. We found that NTC@3.8k ohm when it stop charging. Can we ask the battery manufacturer to change the NTC to 10Kohm@25℃ and 3.8Kohm @40℃ characteristic curve? Will there be any side effect?
Thank you.
Best Regards,
Cindy