Clare says that with series charging. all those rules and factors are
not relevant. Maybe you can help explain it to him?

--
Christopher A. Young
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..


"Jeff Thies"
wrote in message ...

No. If the batteries aren't the same size or the same level of
discharge
the strongest battery will take most of the charge. This is similar
to
memory effect in NiCad. Don't put them in series unless the
batteries
are even, which is unlikely outside a device that needs three.


Actually you have it WRONG.


About what? Surely you are not advocating charging 3 unequally
discharged backup batteries? That *is* the point. There is nothing
wrong
with charging in series provided the batteries are similar and in a
similar state. Not that they would blow up, but the charging would be
unequal with the weakest battery taking less and less charge after
every
cycle until it was dead. Hence the advice to discharge completely your
NiCads from time to time, so they all start at the same (fully
discharged) level. This is all basic ohms law with the voltage divided
between all the batteries, the weak link progressively falls in
voltage
and hence the amount of charge it is given.

For unevenly charged batteries or batteries of different types, the
best option is to charge them independently.

FYI, large battery arrays are usually in a series/parallel combo of
some
type. Look it up yourself.

Jeff