Rebuilding cordless tool batteries

[Pat]

One guy would probably never buy enough component cells at one time for his rechargeable battery packs to get a low enough cost to help make it practical unless you are adding a zillion NiMh or Li-Ion cells to your Prius to make it a PEHV (Plugin Electric Hybrid Vehicle.)

Look here ----> Get your cordless batts rebuilt here

They claim any brand 12-18 volts, longer run time than stock, and two weeks turn around time at $35 per battery pack. I think some of the batts are $20... it depends on voltage. They use 2000mAH cells.

Might be worth a try as the price is attractive.

This was from an ad in the latest Pop Sci.

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[rozett]

I've also been wondering if anyone has used one of these outfits. There is a guy on eBay called Battery Pack Rebuilders LLC that advertises for about the same price. I have a Porter Cable 12-volt drill that's about 10 years old and still works great. Rebuilding is about $20 cheaper than trying to find a new battery.

[gsganzer]

I almost did it for my 18V Milwaukee. Then I found a new pair of 18V Milvaukee's for $89.00 (Additional $13.00 for shipping). It was close enough to the rebuilt prices ($35.00/ea plus shipping) and I didn't have to wait two weeks. In fact I ordered them on a Tuesday morning and had them the next afternoon.

[twstanley]

I rebuilt one of my Dewalt packs with some nicad sub-c cells I had laying around from when I used to race r/c cars. Getting the layout to fit back in the battery case was a bit of a challenge but I got it right eventually. I think I needed a jig, haha.

The battery works really well now, I have another one to do as well if I can come up with enough cells. I might try redoing one with nimh this time to see how they work. I have been impressed with the AA nimh batteries I have been using at home.

[Pat]

A potential downside is the charger might not match the cell's chemistry if you change cell types. Make that probably won't. This will not be a good thing for the cells.

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[Stimw]

I buy batteries on sale at Harbor Freight for less than $10. and remove the cells and install them in my battery packs. The packs are screwed together. The batteries are spot welded together, just rip the tabs off with pliers, clean and solder back together for your pack.
I was even able to add 1 extra battery to my Craftsman and get 13.5volts. With the vari speed it dosen't really matter and now it has more power.

[Pat]

All this talk about rebuilding batts... ARHHHHHGGGGG, now one of my Craftsman packs died. I'll have to buy a special security driver bit to take the case apart as the fasteners have the raised thingy in the center to prevent using a standard bit. Ill see what it looks like in there. Frequently the flash light type cells are super light duty, amp-hour wise, compared to the "right" type of cells. You need to be careful when soldering the cells to not overheat them which will rob considerable life from them.

Use a hot iron with a decent sized chisel tip to transfer a lot of heat in a hurry so you can get in and get out before you transfer too much heat. The trick is to get the joint hot really quickly and remove the iron before the total heat transfer is enough to damage the cell. Pre tin the connecting strap or wire and it helps if you have some additional electronic approved flux to coat the parts with prior to soldering. NEVER use corrosive plumbing type flux or soldering paste!!!

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