i have this cordless drill that was gifted about 1-2 years ago. Now after a full charge (up to 2-3 days charging), I would operate the drill for about 10 seconds and it would lose all power.

So I took the battery apart cause I read a diy on how to replace it's pack with a lipo battery pack. But I have a question:

What would be the best option?

A. Buy replacement 1.2V and solder in the replacements.

B. I can't find the replacement part as a unit, online, so buying the complete battery pack seems to be a dead end.

C. But some smaller 12V 1300 mah pack and attach it at the bottom of the drill and cover it somehow.

 

C. But some smaller 12V 1300 mah pack and attach it at the bottom of the drill and cover it somehow.
View attachment 186646

Might be the best solution, won't the small cells go in the bottom case?
Max.

 

Yeah I'd have to find one that is small enough to fit in the drill handle.

 

Many of today's cordless tools are almost giveaways so you will buy the batteries. A lot are sold without batteries.
1) You will pay about$2.50 to $3.50 each for OEM style, paper insulated sub-C NiCd batteries.
2) An 18 V or higher battery is pretty much standard today, it seems. I have a very old 14.4 V, 1/4" impact tool that I like. I debated long about whether to rebuild the NiCd battery pack or buy a newer one (likely lithium battery). Ended up making the battery pack mainly because I have several NiCd tools and more chargers than I can use. If that were not the case, I would have updated to the newer lithium chemistry batteries.

Every case is different. We don't know what tools you already have and how much you use them. One advantage of lithium (and NiMH) cells is that they have a slower self-discharge than NiCd.
(All prices based on US location.)

 

I agree with "jpanhalt" that it is probably better to buy a new drill with a Li-ion battery. The motor out of the old drill may be suitable for your motorised blind project.

Les,

 

Thanks for the blinds project tip. I actually ordered some motors for it . And I also am printing a sprocket piece for a stepper that has the holes for the bead chain which I'm guessing won't present the holding torque issue which made my blinds unravel when the stepper was directly connected to the tube.

As for the drill, I can't seem to find a 12v pack that would fit in there. I found a few on Amazon for $20-30 but I'd have to get the charger for it as well and it won't fit nicely so yeah, I might as well get the new one. I just hate throwing away stuff!

 

I just hate throwing away stuff!

Welcome to the club. I've got tools that go way back -- some from even before I was born (inherited from an uncle).

I am really annoyed when a nice tool, like my 1983, 4" Milwaukee angle grinder can't be repaired because the trigger switch burned out and a replacement isn't available. Fortunately, only half the switch was being used, so I turned it around, and it is as good as new.

 

An alternative if you have a 120/12v secondary transformer kicking around is to see if it will fit the battery bay, plus a bridge rectifier a fit a mains cord.
Max.

 

I have an old drill that I've removed the batteries and added a long lead with a cigarette lighter plug. Very handy to be able to run it off a car or 12V power supply.