no i do not agree. if the battery stays cold that doesn't mean anything...
yes a battery can die this suddenly. recently my t39's original battery died very very unexpectedly. i was using the t39 as a gprs modem in one afternoon then after ending the gprs session, switched the phone off
(battery was at around 40-50% then
), went home, wanted to turn it on again in the evening and it wouldn't. it wouldn1t even charge. i put another battery on it and it worked OK, charged OK. just the dead one won't. not even the charging LED comes on. oh and battery remained cold.
so i'd suggest it's worth rebuilding the pack
especially as the 820 won't even run with the battery without AC even though it should still have a little power
(8%
) to drive the 820.
(btw it wasn't a good idea to let it run down to 8%... that's almost full discharge. may have been the last straw for the battery
)
before that, you could try charging the battery directly - this may not be too safe, i never tried it but it is possible. just watch its voltage and when it reaches 8.3-8.4V
(the 820 battery has 7.2 V nominal voltage, doesn't it?
), stop charging it. just to be safer