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Charles Schuler Charles Schuler is offline
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Default Upgrading NiMH AA's in dvd player battery pack


"Dan" wrote in message
...
I was recently given a portable DVD player for signing up to DirctTV. I
didn't expect it to be the best one on the market (smallish screen for 1
thing) but I thought it would be good for watching a movie during frequent
2 hour plane trips I have to take. Plays fine, decent picture, BUT the
batteries crap out after a little over 1 hour (you'd think at a minimum the
thing would be good for one 2 hour film). So I opened the battery pack &
as I suspected, found 7 NiMH AA cells, marked 1300 mah. I see that NiMH
AA's are available up to around 2700 MAH. Swapping out the cells is
straightforward, but I'm wondering if the current charger would be up to
the task of feeding them.


Should be fine.

Looks like a fairly decent circuit (multiple ic's,
anyway) which includes a thermistor taped to the cell pack. Whether this
is how the circuit senses a full charge or whether it's an overheat
detector, I don't know.


Overheat.

But again, the circuit does appear to be a bit more
sophisticated than those I've seen for drills, etc, which do rely on the
crude temp method to indicate a full charge. Might this charger be able
to handle cells of 2X the capacity of those the unit came with?


Should be fine.

How could I
test this, short of actually buying & installing the higher amp cells? A
measure of charging current with the present cells, maybe?


No need to test.