Would be nice to learn how properly replace batteries in a battery pack of drills and other tools with NiMH or Lithium batteries. I guess a spot welder is used for soldering part.
Good to know the proper way to do that because extra heat can blow the batteries or damage them.
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A question, can super glue be used to “solder/weld” the terminals instead?
Does super glue conduct electricity?
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No and no. Superglue is not an option.
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I believe that the e-lab has a soldering device spot-welder specifically designed for battery pack building. Looks like a Sunkko 709A from what I recall.
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Most of the newer lithium packs are designed to not be reparable at all. The battery voltage control will permanently lock out if battery voltage ever drops below a certain minimum (to prevent catastrophic battery failure), and they’re often constructed using generous quantities of curing resin or glue.
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Not with that attitude!
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LOL, almost any major tool pack can be rebuilt. including
irobot, Milwaukee, Ryobi, DeWalt, etc. etc. ect.
Cris.
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well, he’s not wrong.
I know this to be the case with mikita specifically, but I’ve been told on others. specifically for modern Li-ion packs, they have an under-voltage protection which permanently bricks the battery pack if it’s detected. Of course, a poor performing battery pack may be able to be upgraded, but if you have a bricked one, I have not had success in reviving it.
Maybe replacing the battery pack control board?
(that’s from 2015 so things may have changed since then…)
Yeah, I didn’t got that far.
I have a friend that is a model airplane guy and he uses sealed model airplane battery packs and their matching smart chargers.
The model airplane packs come in 2, 3, or 4 cell varieties and the charger will charge any of them. (I think each cell charges up to about 4.4 volts).
The battery packs have short leads attached to them that mate to the smart charger, so he just drills a small hole in the battery pack and leaves the small wire dangling out so he can attach the charger. The smart chargers cost about $10 and can be run from a spare laptop power supply. They charge each cell individually and mine shows the individual voltages on each cell as it is charging.
You can buy separately the small connectors that you solder to your external battery leads and then plug them into the battery pack, so you don’t have to touch the batteries.
If anyone is interested, I’ll try to get a picture of my setup so you can see what I am talking about. The airplane batteries are very powerful and compact and MUCH cheaper than replacement tool batteries.
I have a Dewalt 18V drill and 2 converted battery packs and I love it.
Here is a link to a battery pack:
The yellow lead goes to the tool and the tiny white connector dangles outside the battery pack to connect to the smart charger.
Here is a link to the connector you solder to the tool leads:
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=43759
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You know one upside of a LiPo battery experiencing spontaneous exothermic self-disassembly on a RC vehicle vs shoehorning one into a power tool? Unlike a power tool, the RC vehicle has some tendency to be away from you - and likely away from any valuable project you’re working on - at the time.
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That’s a good point. I guess I always assumed that I would be able to jettison the tool quickly enough to avoid harm but that might not be true in all cases. Thanks for the warning!
Not to say that li-ion is perfectly safe by compare - just that they seem less prone to that sort of thing and have much more robust cans containing the magic smoke than li-po’s do.
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Oh snap, that saves me from having to build one out of a microwave. This is in the electronics lab?
Someone that’s actually been in the e-lab lately might be able to confirm.
Different strokes for different folks. I always thought they were airsoft batteries, after a while I would use them for other things that needed rechargeable batteries that needed to last long.
I had to hook up one of my 12v DeWalt batteries to the other to give it enough voltage for the charger to see it and charge it. That has an interesting Google search and experiment that worked. 
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I’ve performed this trick with NiMH cells occasionally. Helps that I have some 3xAA : D parallel adapters.
However, the issue here is the pack circuitry that effectively bricks the power electronics in the pack if the cell stack goes to 0V. I don’t know the specifics of the mechanism, but it does not appear to be something the user can easily correct.
If you’ve got the pack open to replace dead cells, a fix is a new control board away.