RR NDB writes:
On
inconceivable look to the battery picture. Certainly the design
doesn´t control the current independently in each cell.
I wasn't aware you were referring to independent current control. And I'm not aware of any multi-cell Li battery packs which do limit current on a cell-by-cell basis.
Sys writes:
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 ?.
I read somewhere that temp sensing is overall, rather than cell by cell.
Given the relatively "light" weight of these cells, and the corresponding lower rate of thermal inertia, I'd guess that a cell could overheat in one area before a sensor located on the opposite side could sense the climb. Perhaps thermal curves could be modeled to predict this, but if I were designing the bugger I'd certainly have at least 2 sensors per cell.
Cheers!