On Sun, 14 Mar 2004 12:57:05 GMT, Ian Stirling
wrote:


NiMH cells don't really like fast discharge, so are not the
best choice in all cases.

Probably not .. I know the 3000mA sub 'C' NiMH Sanyo's in my 12th
scale Yokomo MR4TC (4wd model touring car) that go from fresh charge
to flat in a 5 min race do end up quite warm!

How many cycles, before a cell/most cells fail?

[T] Em, not sure .. I was racing several sets all season (once a
month, all year) at that pace and didn't have a cell fail? In fact in
my 30 years or RC car racing (sponsered driver for some of that) I've
never had a cell fail? I have seen others have cells fail, I've
marshalled a car that just turned into a heap of glowing red wires in
a matter of seconds but I've still got packs Nicad and NiMH that are a
good few years old and are still going strong?

The 'top boys' generally only run each pack once / day but at 50 quid
a pack and possibly 8 rounds plus finals / race day *I* had to
recharge all the time?

Mind you, the 'pits' have changed quite a bit over the years .. looks
more like a lab at NASA these days with all the digital delta peak /
fan cooled charging stations and comm turning lathes .. ! (some folk
actuallt strip the motor, skim the com, rebuild / lube the motor,
solder in a new pair of brushes ..and solder the motor back into the
model (connectors waste power) after EVERY 5 min heat!

Some power tools approach this sort of drain.

Ooo err .. The only other things I know that can kill a battery in no
time flat are some digital cameras?

All the best ..

T i m