dewalt dc988 randomly stops working after supposedly fully charged battery

[amateur_24]

Hi my dads dewalt the power just keeps cutting off . Everytime we charge it it will works for a bit then totally stop working.
I have taken apart the flaming battery. It's build like a bomb shelter. It took much percussive maintenance to open.
Ironically I used a dewalt drill to disable the pointless security torx. LOL What a fail and waste of money it was for dewalt.

Anyway I couldn't see anything obviously wrong with the cells they looked fine. The ones that I could see without further destruction.
How can I test the lithium ion battery? It does measure 18volts across the terminals.

 

[Zerotolerance]

I would start by determining if the problem was in fact the battery or the drill first. Take the drill up to home depot or the like and test the drill with one of their batteries they use on a demo tool.

 

[amateur_24]

Can I use a variable power supply instead I don't think be able to find somewhere that sells a drill with the same battery. Dewalt seems to have changed their design. I'm also struggling to find compatible batteries that are lithium ion. Theyre like either nicad or NiMH. If it is the battery any chance of me replacing the faulty cells out?

Also if am not mistaken DC motors have brushes which is basically the power connection to the motor. These wear away. Quite possible since its at least three years old and had fair usage. Is this hard to replace? You probably worked out am a complete amateur

 

[KeepItSimpleStupid]

There is a dc988 dc988V and the batteries listed in both are NiCd: https://www.ereplacementparts.com/search_result.php?q=dc988

At the price they are charging for the battery pack, a battery rebuilding service MIGHT be cheaper.

If the age of the batteries are 3 years+, then I would consider replacement.

Checking the brushes is a good idea. What does happen in DC motors is the armature may develop an open, so the drill won't move until something jiggles the motor.

 

[amateur_24]

The drill I got from screwfix must be repackaged one then because it clearly states Lithium ion on the side in capitials. What does the armature look like is it the metal clip thing that's touching the brushes.
The brushes look fine only about 10mm down from the top of the little holder on both sides. So I can use a continuity tester to test the armature right?

 

[KeepItSimpleStupid]

The poles opposite to one another will have continuity with no shorts to adjacent poles.

I THINK DeWalt does have a Universal charger which means something in the pack or mechanical alignment determines the pack type. Not sure though. I think that's how they make the chargers universal.

 

[Zerotolerance]

I own nothing but Dewalt power tools. The new lithium ion batteries are compatible with the older tools. I am having a hard time understanding why you cant locate a battery.

 

[KeepItSimpleStupid]

Well, I gave him a source and it looks like it's like $140 or so. Expensive.

I have a varied collection. DeWalt, Makita, Bosch and others. All seem to be well made. Dewalt reaaly messed up on an angle grinder case. You can't really store any accessories in it. They should leave enough room for the power cord doesn't get stressed and have enough room for a few accessories. Wire brush wheel, grinder wheel and a wrench for the wire brush. It barely fits.

You'll laugh why I bought the angle grinder. It removes the grass that grows between the pavement/sidewalk after killing it using the wire brush on the edge. I may have also needed it to slice through a cast iron pipe.

I bought a Harbor Freight Reciprocating saw, but haven't used it yet. I need to slice through a 4" drainage pipe buried 18" underground.

The jig saw is a Bosch and I absolutely love it. The harder tool to justify was a 20 ft-lb Bosch Demolition hammer. ebay and then rebuilt by me. Clay spade, 4" tamping plate and Chisel for a digging project.

Another tool that was hard to justify was the DeWalt stud and joist drill. So, aside from drilling a few studs and joists, it's used for a garden auger.

 

[Zerotolerance]

Dewalt reaaly messed up on an angle grinder case. You can't really store any accessories in it. They should leave enough room for the power cord doesn't get stressed and have enough room for a few accessories. Wire brush wheel, grinder wheel and a wrench for the wire brush. It barely fits.

Ya pretty bad design on the case. I hear your frustration

 

[clel miller]

Does this drill use the older NiCad batteries.?
Mine did the same thing.
I had 2x9.6V batts and 2x12V batts.....they were all 4 bad. Would charge, but then run down with about 10 minutes of steady use.
One New battery were almost as much as a drill.
I had one of each battery rebuilt. Been using those for about a month now. They seem to work pretty well...MUCH better than they did.
I think it was about 35 bux to have each batt rebuilt.
best