Lyman:
The prismatic shape and the folds produced, cannot dissipate heat quickly
enough, or efficiently enough, to enable a long life and efficient profile
for the "Eight battery group" as built by YUASA.
So, what about all the other applications for these cells, for which we
have no news of any problems ?. As I said in an earlier post, they
have been approved for use by NASA, the ESA and others only after very
extensive testing, so are they all wrong ?.
The whole idea is for the cells not to overheat in the first place, for whatever
reason and that's down to good design for the bms..
Battery topology really doesn't matter, so long as they are operated
within data sheet limits. All li chargers utilise temperature sensing and
should backoff charge current to avoid overtemperature. Sensing is
critical, hence the earlier disussion about individual cell temperature
sensing, as opposed to overall enclosure sensing.
Laptop batteries may get away with a single sensor, but it's just not
enough for an enclosure of that area. If there's adequate sensing, the
cells won't overheat to start with.
Of course, this doesn't cover the high rate of discharge case, such as
apu starting, but once again, the battery can be safely disconnected from the
load if excessive temperatures are seen by the bms...