I was reading a Mooch review of the P28B and he says:
The datasheet only lists a temperature-limited discharge current rating of 40A. According to the datasheet you can run the P28B at 40A but you must keep the cell temperature below 80°C. Since this cell reaches over 110°C when discharged continuously at 40A we cannot use that as a true continuous current rating.
For direct comparisons between cells I rate the P28B at 25A continuous/40A non-continuous (as long as you keep the cell below 80°C).
Molicel is not trying to fool us with their ratings. Their cells are rated for the applications they’re typically used for; electric vacuum cleaners, power tools, and other products that draw lots of power for short periods of time. Molicel’s datasheets are written for the engineers from their large commercial customers who know how these cells are rated.
Similarly, Mooch’s P45B review says
You cannot run the P45B at 50A continuously until it is empty! This non-continuous rating is set by Molicel for this cell’s intended applications
While you can run this cell at 50A for a while I recommend staying below about 35A
I take this stuff real seriously. Theoretically, if the heat conducts from the battery to the host, it should get too hot to hold before its in danger zone. But in headlamp, we might not know. Of course, the driver should also shut down properly if it overheats.
But still, I am wondering, how do we know the “temperature neutral” maximum sustainable current for P30B above which it goes into thermal runaway? I’m not sure how Mooch arrives at his estimates.
