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hello!
do we know of anyone who can build battery packs - similar to what's in rc cars? i've got 2 12v torches (military spec) which are rechargeable, and simply can't afford the price they want! (cheapest so far is £60 for 1 pack!)
anyone with any ideas?
baz

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Would also be nice if some enterprising Wiki-er could rebuild battery packs for rechgargeable handtools.

How many of us have a (mechanically) perfectly battery drill in the toolbox but the damned thing will no longer hold charge for more than a 5 minute job? I have TWO such drills. Because they are mechanically sound I am just too mean to throw them (and the chargers)in the bin

While you can get replacement battery packs for posh kit like DeWalt etc (at a heck of a price) there is no chance for a Black & Decker or a PowerCraft. I could not even get spares for a Bosch drill

Potential business here I suspect

Snod

i like your thinking snods! ...anyone?? haha

I've done this many times, biggest problem is that most of them have NICADS in them which inherently have problems because of there memory effect. Often the packs are fast-charged but without proper thermal protection which means some cells get too hot and are destroyed. The batteries are connected in series and hence charged in series, any imbalance in one cell will magnify the memory effect problems.

If you replace them with NiMH batteries they are easily destroyed as well because they are very intolerant to overcharging at faster charge rates.

The real answer would be that manufacturers revert back to using standard generic cells that can be charged and tested individually - but of course that would reduce their re-sell rate enormously.

DD

Last time I priced appropriate battery cells (ideally tag-end to make connections easier) the cost to rejuvenate my drill was more than the cost of buying a new drill.

THAT can only mean that a mere mortal like me cannot buy cells as cheaply as the manufacturers. If I bought cells from a low cost source eg alibaba.com then I could just about break even.

Snod

Yes, they are a bit dear, I used to buy in bulk (50 to 200 at a time). Usual size of cells and are between £1.50 and £2.00 each at the moment - eight cells and your looking at up to £16

And the last battery drill I bought was £14 from Netto!

Yep, it will be knackered (battery) in a year or two - and I guess it will go into the box with the other dead ones. I have to say that for £14 it is a very reasonable drill. Obviously no hammer action etc, but it all works for what I want.

Snod

You can get the cells from abroad a lot cheaper, but lead time does my head in.

i have a battery for my impact gun which i dropped and its stopped working, care to try and fix it dd? i will pay

@Chris, Sure mate, I'll pop down tomoz, I need to see you anyway

ok buddy, sure you'd like to see my new project anyway

Sounds interesting!

1976 and air cooled

911E?