Rebuilding battery packs? 🤔

[rivermobster]

It appears you need a Battery Spot Welder, prices are between fifty and hundreds of dollars.

The batteries, prices between 1 and 20 dollars.

And some nickel strips, I didn't price that out.

With the price of new battery packs, this equipment would pay for its self pretty quick!

Has anybody tried this yet?

 

[bilz]

Seen it done at work. Isn't to complex with the right tools.

 

[Go-Fly]

I wouldn't mind it at someone else's house.

 

[rivermobster]

I had one dead cell.

Almost blew myself up, taking the apart!

Looks time consuming to me...

 

[coolchange]

I’ve got one I was going to tear apart.
Car battery spot welder?

 

[mesquito_creek]

It appears you need a Battery Spot Welder, prices are between fifty and hundreds of dollars.

The batteries, prices between 1 and 20 dollars.

And some nickel strips, I didn't price that out.

With the price of new battery packs, this equipment would pay for its self pretty quick!

Has anybody tried this yet?

View attachment 1467841

Yes… I make my own lifepo4 batteries out of 18650 cells. I use a cheap spot welder and nickel straps.

 

[lbhsbz]

I've done it...depends what your time is worth.

 

[rivermobster]

Yes… I make my own lifepo4 batteries out of 18650 cells. I use a cheap spot welder and nickel straps. View attachment 1467883

View attachment 1467884

Nice! What spot welder did you buy??

 

[TimeBandit]

Look at YouTube for DIY battery spot welder I seem to remember a few there

 

[rivermobster]

Look at YouTube for DIY battery spot welder I seem to remember a few there

There are a whole bunch of different ones. Just depends how much you're willing to spend.

 

[spectra3279]

Done it with solder and a soldering iron.

 

[TPC]

Those battery stores will usually do it.
I had a cordless Impact wrench I loved.
May have been an early HF, I forget.

The batteries puked and no replacements available.
I had the packs rebuilt at the local battery place and they went dead later that year.

His keybob coin batteries died pretty quick too.

 

[DLow]

If you are going to go through the process, make sure you are using quality battery cells, not the cheap Chyna eBay crap. Oh, I’d recommend charging them the first couple times outside… in the middle of a field, using a long extension cord, with no one around, and nothing you enjoy owning in the vicinity. Good luck!

 

[badgas]

Batteries ?

I thought RDP was anti battery and anti electric ?

That is interesting. I used to solder and assemble battery packs when raced RC cars.

 

[mesquito_creek]

Nice! What spot welder did you buy??

A cheap china unit off of amazon…

 

[mesquito_creek]

I also use some cheap cell capacity testers…

 

[rivermobster]

A cheap china unit off of amazon…


View attachment 1468033 View attachment 1468034

That's the one I was thinking about also.

For what I'll likely be doing, there is no point in spending hundreds of dollars.

Thanks.

 

[lbhsbz]

If you have a couple failed packs, You don't need new cells....there's usually only one, maybe 2 bad ones per pack. I used a R/C charger to charge each cell and balance them all, then simply replaced the bad with good used out of donor packs.

These days, I just buy new packs because more often than not the battery gets left out in the rain or something and ends up full of water, and the board is all fucked up. I got 10 years out of about 10 Dewalt packs I initially bought....that's a pretty good run. Still have 6 of 'em that are going strong. They don't owe me anything at this point.

The aftermarket units (that I've tried) are garbage.

 

[ltbaney1]

you guys are brave! i wont let my factory dewalt or Milwaukee packs charge unattended. ive seen too many battery fires at RC car tracks to trust them. let alone some home built jobby i did while sitting in the garage.

 

[rivermobster]

If you have a couple failed packs, You don't need new cells....there's usually only one, maybe 2 bad ones per pack. I used a R/C charger to charge each cell and balance them all, then simply replaced the bad with good used out of donor packs.

These days, I just buy new packs because more often than not the battery gets left out in the rain or something and ends up full of water, and the board is all fucked up. I got 10 years out of about 10 Dewalt packs I initially bought....that's a pretty good run. Still have 6 of 'em that are going strong. They don't owe me anything at this point.

The aftermarket units (that I've tried) are garbage.

I have one dead cell in the pack I pulled apart.

Good idea about saving the good ones.

 

[TimeBandit]

One of my four amp hour M12 packs wouldn't charge at about 2 years old a co-worker had all the tools and batteries and fixed me right up.

None of my other lithium packs has failed many are 8+ years old at this point.

Remember when 7.2 volt Makita nicad drills were the bomb?

 

[mesquito_creek]

Not all lithium is the same. I only do lifepo4 because it doesn’t have thermal run away issues, it’s very safe.

I also agree with @lbhsbz that it’s not cost effective, I do it as part of my crazy prepper stuff and have a lot of off grid electricity needs.

 

[rivermobster]

One of my four amp hour M12 packs wouldn't charge at about 2 years old a co-worker had all the tools and batteries and fixed me right up.

None of my other lithium packs has failed many are 8+ years old at this point.

Remember when 7.2 volt Makita nicad drills were the bomb?

I think I still have one of those buried in my toolbox somewhere!

 

[wzuber]

It appears you need a Battery Spot Welder, prices are between fifty and hundreds of dollars.

The batteries, prices between 1 and 20 dollars.

And some nickel strips, I didn't price that out.

With the price of new battery packs, this equipment would pay for its self pretty quick!

Has anybody tried this yet?

View attachment 1467841

I've often thought of looking into it but waste too much time on rdp to bother w/searching. Haha
Say, by the way, how's that electrical class you were going to teach coming along?

 

[rivermobster]

I've often thought of looking into it but waste too much time on rdp to bother w/searching. Haha
Say, by the way, how's that electrical class you were going to teach coming along?

Louie and I were thinking February or March.