I was able to post this week's video ON Friday. We shot a good bit of it last week. So this week we do a 4C load test of four CALB 100AH cells.
The test actually consists of 40 pulses of 400AMPS lasting 2.5AH or about 30 seconds. The CALB cells list 4C for 30 seconds on their spec sheet. We do a full 100 AH with every single tron coming out at a 400A rate (well, until the end when it more or less collapses).
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Here is the Microsoft Xcel spreadsheet chart of voltages and temperatures experienced across the test.
The good news is that the cells will indeed do 400 amps quite handily. I think the bad news is that at that rate, the Peukert effect does come into play and you will get a little less than 100 AH from the cell.
Overdischarging the cell of course is damaging. We had venting after 95AH and indeed lost a cell. But this was not entirely accidental. One of the things we wanted to demonstrate was failure under a substantial load from overdischarge. No fire. No explosion. No thermal runaway. In fact, when we did discontinue after 99.9AH, all four cells cooled fairly rapidly.
Interesting test. You'll want to watch this one.
Jack Rickard
