Rebuilding DeWalt XRP 18V Packs.. Help?
 

Hey guys,

My dad's old packs finally have died..

We have two, one measures ~7.4V using the main + and - terminals, when measured with the + and middle (I assume kinda like the balance port), also measures this, when measuring the - and the middle, nothing. Sounds like one group is dead to me, or there's a short/open circuit here.

The other pack is 0.00V across the board...

We've taken the cases off, and I'm starting to chip into the glued, uhm... cardboard... to try and measure each individual cell to whether they need replacing or just need to be cycled...

Is there anything I need to be wary of? Or any tips?
I was never found of the 'balance port' so any insight on that would also help.
In addition, links to good, recommended new Sub C cells would be awesome!

I know a few of you have tried this, and some succeeded, so just looking for input, thanks!

MY tip, go buy new packs! Usually can find a two pack for $100. What your going to put into the packs you have in new cells and time will far exceed the price of new ones unless you only value your time at about $2/hr. Or look into the lithium XRP packs. I just boutght a drill with them, they are smaller and have more power.

Hmm, my dad saw a sale @ Lowes, 2 for $100, but he wants to wait it out a bit, see if they'll drop with the new stuff coming out (Nano, Lithium ION, etc).

Our initial plan is to salvage what we can, and piece together at least one pack..

The 18V packs I have taken apart have 10 (5 pair) of the smaller A123 batteries. They are not that difficult to take apart, you might find the dead pair and replace them with a good close match from the other pack.

Jeff

We ended up trashing them all.

We found the middle prong shorting against another prong, which probably shorted and killed all the cells in that pack.

In the other, it was only measuring 7, the majority of them were all dead.

In the end, we'd be spending about $50 for a pack, not to mention solder tabs and the time to actually solder them (we don't have those solder punches/whatever they use).

I think we will end up purchasing new packs..

Bummer, was really looking forward to experimenting with these cells!

I have brought back many A123 cells. In fact I have 2 2S2P packs that each had a set of DEAD cells I bought off of ebay a couple of years ago and they are still good today. I start by charging them as a Nimh 1 cell at about .1A then when the voltage starts to come up I will switch to a 2 cell Nimh at the same current. Once the voltage gets to 2.5 or so then I charge them as a normal LiFe cell at the same current till done. Just don't walk away and watch them and you will be fine.

Jeff

Besides the fact that the packs in question where already trashed, I'm pretty sure the packs he was working with are ni-cd. The XRP packs have been NiCd until recently when they released the Li-Ion 18V XRP pack.

It was more of an FYI thing. I noticed that he said balance ports and went on that without fully reading it, and "recently" means different things to different people. Like the "recent" purchase of a starter battery for our forklift was 8 years ago, at least to me it was only a year old.

Had I paid attention that they were Sub-C my suggestion would have been much different.

Jeff