Rottenray:
Some time in the past, a poster (here or somewhere else) mentioned that an inspection showed wiring errors.
I wonder what they were and where they were at.
If a harness was mis-wired so that charge sensing was swapped between two cells - cell A being read as cell B and vice versa - it would eventually lead to an overcharge situation.
If the swap happened on cell temp, then a cell going into thermal runaway would be allowed to do so as the corrective action would be applied to the wrong cell.
I didn't see that post, but it seems unlikely, since the manufacturing
process for such an item would have have visual inspection and test rigs
to ensure that the wiring was correct. and that it functioned as expected.
If voltage sensing were swapped between two cells, i'm not sure it would
make that much difference if all the cells are charged in series, since
you can only vary the overall charge rate for all cells, not individually.
Would make a lot of difference if there were a charging circuit for each
cell, though from the pics of the internals, doesn't look like that is
the case.
There's another point that may be relevant as well: It's not clear from the
pics if there is a temperature sensor per cell, or a single sensor for
the enclosure. I don't have figures, but the cells could have significantly
less thermal mass than say lead acid or nicad. ie: they might heat up much
faster than the latter. They also have a fairly low max operating temp of
65 C. If you have a single sensor at one side of the enclosure and a cell
starts to overheat at the opposite side, would that single sensor detect the
overheat condition in time to shutdown the battery ?.
May be irrelevant, if there's a temp sensor per cell, but the failure also
raises the question of whether they tested the overall system for all
fault conditions, including that to destruction...
Regards,
Chris