I think my DeWalt 18V batteries are on their last legs. The drill
still works okay, but when ripping 2x4's into 2x2's with the circ-saw,
I get about done with one before the saw doesn't want to go anymore.
Maybe it's the saw, but me-thinks it's the batteries since they're
about 5 years old. Anyway, looking on ebay for new batteries since HD
wants $80 apiece, I see several people selling "How to repair your old
battery packs - like new performance" guides. These claim to be able
to repair old batteries, specifically for tools, for either nothing,
or at most $2.00. I know a little about electronics and battery
chemistry, and I'm pretty sure that when NiCD batteries die, its the
chemistry inside that's the cause. Without putting in new cells, I
don't think there's much you can do and new cells cost a lot more than
$2.00 (at least the amount I'd need for an 18V pack). Just curious if
anyone has tried to repair batteries on your own, and if so what was
the result and what did it cost?
If you got a Batteries Plus store around you may want to give them a shot. I
inquired there one time and it seems they were about 60% of new cost to
rebuild your old with new batteries in your case. This is the reason though
that I have replaced my last two drills. It only cost about 30% more to just
buy an entire new drill with batteries, charger, and case.
On Tue, 13 Nov 2007 15:59:39 -0800, firstname.lastname@example.org wrote:
No, you cant really repair a Nicad cell. If its shorted, you can try
to blow the whisker out thats punctured the internal insulator but it
usually doesnt work, and if it does, it usually comes right back. If
the cells are reversed polatiry, you can try to jump them with a good
cell and that sometimes brings them back, but again, it usually doesnt
last for long. And if the cells are just leaky and self discharge
overnight, well, nothing you can do there.
The local Farm & Fleet store is currently selling two 18V batteries
for $110, which is a bit better than $80 for one. Home Depot has had
this deal in the past too.
Also, when rebuilding the packs, the Dewalt packs use 2 AmpHour
cells, the cheaper cells that some rebuilders use, and even the
similar Black & Decker 18V packs, are only 1 AH so you have to be
I've done a few experiments, and the "blow the whiskers" trick
usually works to a certain extent, but I wouldn't expect it
to be particularly effective or longlasting on an oldish NiCd cell.
Eg: if the cell is leaking, this _might_ make it work for a while,
but you can betcha not for long.
But on a reasonably new battery that mischarged for some reason
might just come back to operation for the rest of its normal
expected lifetime. If the cell is a year or two old, it
can't hurt to try. 5 years? Probably not.
The $13.95 (or whatever it is) set of instructions sold on eBay
(and elsewhere) are exactly that. Whisker zapping. With the usual
"our customers say" bullcrap.
Rebuilding the pack can sometimes be a good option. I had
a Dewalt (but rebranded) 12V pack that said it was 1.7AH
rebuilt. With 2.2AH cells. Works better/more capacity than
even brand-new Dewalt XRP packs. Whisker zapping wouldn't
have accomplished that. Obviously.
Remember these tools are usually made with the cheapest cells they
can get away with that meet their performance/marketing goals.
A battery rebuilder is aiming at a professional market with
very demanding requirements, doesn't suffer from the same
"make it as cheap as possible!" pricing pressures, and it
makes a big difference to their survival if the battery
doesn't perform - they rely on repeat business.
So they'll probably be installing much better cells than
the tool had originally.
You pay more for the better quality obviously. Depending
on what you need the tool for, it may be the best choice. Or
it might be a waste.
[Which reminds me I have to get another one of those rebranded
packs rebuilt. I keep thinking I should double check whether
my charger is compatible with NiMH. Even with AA, I'd get
more capacity (2.7AH), but SC cells are around 4-5AH. And it'd
be lighter... 12V external pack made with NiMH C's. 10AH.
And it'd _still_ be lighter. Whoo! ;-) Ah heck, just use
a car battery ;-)]
Age and Treachery will Triumph over Youth and Skill
On Nov 13, 6:59 pm, email@example.com wrote:
Do you have a B&D repair shop near you? They might have a better
A few (many?) years ago I took a couple of 3 YO 12V Dewalt batteries
and the charger in to see if they would test them for me. They said
the charger was fine but the batteries were shot. They offered me
this: Buy one, and they'd give me one. Who could argue?
There is no repair for the batteries. Some chargers do have a special
cycle for the older batteries to help squeeze a little more life out of
them, but it is not that much.
It is possible to rebuild the battery with new cells. Some places will
do this for you or you can buy the cells and do it yourself if you are
rather handy at such things.
You may want to consider buying new batteries and consider non-DeWalt
brands to save money and maybe getting some higher capacity batteries.
Now having said that, also take a good look at your tools. Are they
getting close to the end of their life? is there a better model out there.
Often buying a new tool is little more than buying the batteries that come
with it. Some times it is even less. Most battery operated tools are not
designed for long life and should be considered expendable.
I agree with your upgrade vs. replace the batteries concept.
When my second set of 12V Dewalt batteries started to go bad, the
drill was also getting a bit tired. Since the 18 Volts were available,
along with a number of standalone tools that would take the same
batteries, I decide to upgrade.
I was at a volunteer function, building some ramps for a Soap Box
Derby race when the clutch on my 12V started to slip. That was all the
incentive I needed to trash it. I asked everyone to step back and
tossed the drill as high as I could and let it come down on the
blacktop. The battery popped out. I put it back in and started the
drill. Once again, I tossed the drill as high as I could and let it
come down on the blacktop. The battery popped out. I put it back in
and started the drill.
OK, time to get serious. I duct taped the battery into the drill and
tossed it again. It took 3 tries with the battery taped in before
there was significant enough damage that the drill wouldn't work
Gotta love a well made tool.
The charger I'm using is one of those that automatically enters a
"renewal cycle" once the full charge is complete. The batteries are
just about 5-6 years old, so I guess I should just be happy I've
gotten this much out of them. I see now on eBay new batteries for
about $40, so maybe I'll just get one of these. I read up on
rebuilding my own, and it looks like the NiCAD cells will cost me
about $32-$35 after shipping and all, and while they'll likely have a
little higher mA, it's just not worth it to me for the extra $5 for a
Also, my tools are still pretty good. 18V is plenty for all my
applications, and they are built like tanks. I've dropped em more
times than I'll admit and they never stop for a second.
One question tho - you mentioned "non-dewalt brands" for batteries -
do you know of any that are compatible with Dewalt tools?
On Wed, 14 Nov 2007 06:20:03 -0800, firstname.lastname@example.org wrote:
Some older Black and Decker packs are compatible with Dewalt except
for a plastic "key" on the case. I dont recall if the Firestorm
batteries fall in this category or not. All you had to do was file
off this key and the pack would plug into the Dewalt charger.
Off course you then had a crappier, lower capacity battery than the
original Dewalt so you really never wanted to do this. But in an
emergency, it worked fine.
I have a Mastercraft 12V hammer drill (Mastercraft is Canadian Tire brand,
it was a rebadged B&D I think), that has batteries that will work
directly in the regular 12V Dewalts, but the capacity is lower (1.7AH).
The Mastercraft batteries expose the shell of one cell, and the charger
also contacts it (three leads in total).
The mastercraft charger will not charge Dewalt batteries, but Dewalt
batteries _do_ fit. The Dewalt charger will charge both, no mods
needed to the mastercrafts.
I believe the mastercraft batteries are B&D Firestorm packs. I
seem to remember the same charger/battery interoperating quirk.
Alternate vendors aren't necessarily bad.
Check out http://www.global-batteries.ca/index.php/cPath/5_97
This sells compatibles for many portable drill lines. The above
link is just for Dewalt. It has a variety of 12V Dewalt packs from 1.5AH
to 3AH. Dewalt XRPs are only 2 or 2.2AH I think. The 3AH pack
is NiMH, not NiCd. 3AH for $42 - about half of what a new 2 (2.2?) AH
XRP costs at places like Home Depot.
Global batteries is one of several names for the same outfit. This is
one of the Canadian versions. There are US specific versions.
They ship out of California, but I think is HQ'd in Hong Kong.
I have purchased a lithium laptop battery and a number of NiMH cells
from these guys. Have been quite pleased with the service and the
batteries themselves. Delivery is quite quick, and shipping costs
are quite reasonable considering it's transborder.
Age and Treachery will Triumph over Youth and Skill
It is WAY past time for standardization of battery power packs. No
reason for each company to have its own footprint which excludes
using any other battery than the one they sell.
If battery footprints were standardized by voltage (all 12 v, all 18
v. etc) than there would be after-market companies making and
selling these packs. Some might be good, some might be lousy, but
we would soon find out which was which and overall, the price would
Of course, few companies want this competition, so this is a long
At first you said:
No reason for each company to have its own footprint which excludes
using any other battery than the one they sell.
Then you posted the reason:
Of course, few companies want this competition, so this is a long way
The Battery Resurrection process you talk about can bring a battery back
to life, so it can be charged again, by zapping the internal cell shorts.
If someone expects the battery to become like a new one then they will be
disappointed in most cases. Because batteries are expensive, it is worth
trying to Resurrect them - some can give really good service.
Battery rebuilding is a good option, but it can cost close to a new
A new universal battery is available that will run any brand tool at any
voltage called the Rambo Battery. I really like that you can use super
high power NiMH cells on a NiCad only tool or even on a Li-ion tool. It is
the most universal cordless tool battery I've ever seen.
For your circular saw problem of not enough power, there is a Rambo
Battery that will allow you to put 3 batteries on 1 bandoleer and you can
use high power cells and even over voltage the saw and it will just keep
cutting until you get tired out. Just do a search for rambobattery
circular saw, recip saw and fluorescent lamp. After a few weeks, I
happened on a special at Lowe's. For about $25 more than I paid for
the batteries (and I did get a good price from an ebay store), I
could have bought 2 batteries, a drill and a charger. I could just
kick myself. You can always use another drill .......... Oh well,
maybe in 3 to 5 years, I'll find a similar deal.
this is just a cloth belt(bandolier style) holding individual cells that
you wire to suit your tool,and use one of your dead battery packs as the
you have to buy the belt,and buy the separate cells.
It turns your cordless tool into a corded tool.
the balance of your tool will also be altered.
A method of converting an old battery pack into one that can be easily
reopened(screw fasteners) and individual cells replaced(without soldering
or welding) by the end user would be far better.
BTW,for an 18V pack,you could replace all the old cells with five 18650
2500mAH Li-ion cells and have a lighter pack,but you'd need to make a
custom smartcharger for the new battery chemistry.
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