replacement drill batteries..

[markus shaffer]

i'm curious if anyone has ever dismantled and replaced the cells within a battery pack for a cordless tool.. i have an older porter cable drill with batteries that are no longer taking a charge. i've looked into replacing the packs, but at $60 bucks each, i wonder if i shouldn't just buy a whole new drill. the drill still has life in it, so i'm hesitant to just buy a new one but at the same time, i'd rather not buy new packs that are going to outlast the drill. these are older style packs that don't fit in the newer drills. also this repacking idea might just be a little crazy in which case i wouldn't mind someone pointing that out to me.

any opinions would be greatly appreciated.

-markus

[Bill Esposito]

If the drill is old, you should consider a new one. I just had to make the same decision with my 13yr old Makita 9.6v. Two new batteries would have been about $65. I sampled the new drills and fell in love with the Bosch compact tough 9.6 and it's one handed ratcheting chuck. At almost 100inlbs more torque than the old Makita and a delivered price (with coupon) of $69 it was a no brainer.

The new drills are generally more feature rich , can be had with NiMH batteries, and have more torque than the older models.

[Steve Roxberg]

What model Porter Cable do you have? I have a MagnaQuench 12 volt that uses the Model 8500 battery packs. I have the same problem, one of the packs no longer holds the charge, but the other one and the drill is fine.

I found a place that will rebuild the pack for I believe $29 dollars.

Even if I buy a new drill, it would be nice to have a second one for around the garage.

[Clem Wixted]

I have 2 drills and packs on the bench right now to replace the batteries. After considrable research I decided to replace the batteries myself. I have a little electronics background but it appears to be straightforward.
First you need to determine what size batteries you need. They will most likely be sub-C batteries. They are a little shorter than standard C batteries. They will also likely need to have tabs on them to make them easier to solder together. It's a bit of a pain to solder directly to the battery.
Second you need to determine if you want NiCad or NIMh (nickel metal hydride). NiCads are probably what are in yours now. NiMh are more expensive but last longer. Likely the same charger can be used.
Thirdly go and buy the batteries. Each cell produces 1.2 volts so your 9.6 volt drill will need 8 batteries.
Lastly, carefully take apart one battery pack (leave the other one as a model in case you run into trouble with the first one. Make up the new battery arrangement using the old one as a guide. There might be a diode and/or a thermal safety device somewhere in the chain to prevent a fire. You should use this on the new pack. Now carefully squeeze all the batteries together, tape might help hold them in place, and put them into the old case and button it up/
Good luck.
Batteries can be purchased ar RC (Radio Controlled) hobby stores. I got mine off of e-bay. Remember to use the tabbed batteries.

[Clem Wixted]

Mine cost $48 shipped for 40 batteries off of e-bay. Retail is about $1.50 to $6.00 depending on NIMh or NiCad and how "thrifty" you shop.

[Clem Wixted]

...that you connect negative to positive, positive to negative, etc. on the new pack. Use the old one as a guide.
Also make sure that you connect the positive and negative to the correct terminals on the pack.

[Bill Esposito]

NiMh are more expensive but last longer. Likely the same charger can be used.

Actually this is not true unless you are talking about overnight charging. If you have a quick charger it is likely that a NiCD quick charger will damage your new NiMH batteries.

For quick charging you must use a charger design for that.

I did alot of research on this a while back because I could have gotten NiMH batteries for my Makita for 20 bucks each...in which case I wudda stuck with the makita.

IMO you are better off either replacing the battery pack with an OEM pack or buying a new drill. Most replacement batteries and even replacement non-OEM packs will not be as good as the original (most non-OEM replacement packs carry a much shorter warranty as well)

[Jamie Buxton]

There are many companies that rebuild battery packs. Here's one that an acquaintance uses: http://primecell.com/