16 May
2001
16 May
'01
11:16 a.m.
On Wed, 16 May 2001, Tony Duell wrote:
Perhaps this is not the place to mention that I was
connecting cells in
series before I ever went to school....
As good a place as any.
I have hooked batteries in series on the fly before, but usually on
circuits not sensitive to gross mistakes or ones where I was not concerned
if my meddling hosed things up. I wanted to take a little more care in
this case and go by the book.
You want to keep the capacity (180mAh in this case)
similar as well. The
charging current for the cells is normally around one tenth of the
capacity, so you'd expect a 18mA charging current in this case. You'd not
want to use cells of a very different capacity unless you also want to
modify the charging circuit (this might be trivial given the schematic,
it might not, but in any case it's easier to get the right cells).
I did some searching and could not find any 180mAh batteries, even among
vendors carrying panasonic batteries (which these were incidentally). It
seems the line has been discontinued since 1990. The available cells were
all in the 220-250mAh range. I hope this is not a wide enough variation
to make a difference, or would I just need to leave the machine on longer
to charge the cells?
Thanks everyone for all the helpful responses...Paul