OT: Battery Charger DIY...

[Chris Crosskey]

HI Folks...

I've just got (well recently got anyway) a Sinclair C5..it's a little
electric/pedal powered trike dating from the mid-eighties for those of you
who don't know....I've got a pair of lead-acid dryfit batteries in it ATM
(the original Sinclair ones died) and they're fine and dandy but....I'm
planning on going on holiday on it next year, and possibly doing a British
mainland end-to-end run for charity either next year or 2001 so I need some
more batteries....I can source 25Ah dryfits quite easily from a friend who
services powered wheelchairs, and for the charity run I can prolly get new
ones from the people who make them, so they're not a problem, but a battery
charger for them is....Given the layout of th eC5, I can carry a total of
four 25Ah batteries on board (100Ah), and I'll put another six or eight in
the trailer I'm building....the problem is charging the things
over-night....the C5's charger can do it's standard 36Ah battery quite
easily overnight, and can do the 50Ah I've currently got installed without a
problem as long as I take the charger to work and have it on there
too...Does anyone know where I can get some advice on a multi-stage charger
design from, selaed lead acid can take quite a poke until it's nearly
chatged when it should go onto float for a while, I can get charger meters,
but I need one charger capable of about 10A peak to do the four on the C5
(I'll run it in through the trailer coupling) and one capable of 15-20A peak
for the trailer's set...gotta be automated, gotta be 240VAC mains...any
ideas welcome....with those kind of peak currents I'll be able to recharge
fully in ten hours, and if I can get some time on chatge at stopovers then
so much the better....

chrisc