Thread: Repacking Panasonic Batteries

Originally Posted by Green Woodchips

Hi all.

Has anyone out there had experience repacking Panasonic batteries for their older type 12v cordless drills (Ni-Cad)? Are the batteries easy to get apart? I'm considering buying one, and am just interested to know BEFORE I get myself into trouble! Also... getting cells... what do you recommend? And what price should I expect to pay? Is it a simple solder job?

Warm regards,
Green Woodchips

Can't help with your question directly as I used this mob to replace the cells in my 7.2v Makita drill batteries:
http://www.batterymaster.com.au

The batteries are fairly easy to pull apart, I think they might use a 'security torx' head screw, but they aren't so secure anymore if you know what I mean.

The batteries themselves are usually spot welded to some tinned metal tabs that fold up pretty easily, so they can fit into a small space. If you try to recover the tabs, you will trash them so don't bother and don't worry about it.

To solder up new batteries, it's not exactly easy nor straightforward. If you have some practical experience soldering, then you should do ok. If you have never soldered before, then this is not the time to start. You will need at least a 60W iron, some good non-corrosive soldering flux and some solder of some kind. A piece of wood with a large rabbet cut in it, or some angle iron/ally will also help alot.

Tale your shiny new batteries, and scrub the ends of them clean. Just a little with some scotch brite, sandpaper or steel wool. Put some flux on there and a little solder on your iron. Stick the iron on the battery and tin terminal but BE VERY QUICK ABOUT IT!!!! If you get the cell too hot you will kill it at least, at worst it will become flaming chunks of death so be careful and quick. Then to stick the cells end for end, put two in your guide (wood or angle) and heat up both ends you want to connect at the same time. When the solder is nice and warm, pull the iron and push them together. Jobs done. Practise on the old batteries first if you need to.

For the cells, stick with nicads. They are much easier to work with and the drill/charger are desinged for them.NiMH are a lot more finicky and you will very likely kill them before you finish re-habbing the pack. Where I am not sure, but any wholesale battery dealer should have them or know where to get them. You will be looking for sub-c size cells, 10 of them. If the original battteries are about 40mm long, they are a full sub-c, if they are closer to 30mm, then prolly a 2/3 sub-c. Most likely a proper sub-c, but some of them use the smaller ones. I'm just guessing here, but fresh batteries, 1700maH x 10 are prolly going to cost anywhere from $30-60 depending on brand. Sanyo are prolly the best, GP and Panasonic are also pretty good. Most everything else is something to be wary of. You migth also find them at Jaycar, but you will prolly have to pay for them too.

Are you sure you want to go through all this? I have zero problem with it, but it's not for the faint of heart or a soldering novice.

Thanks, Groggy and Schtoo.

I could be pretty wild with a soldering iron in my hand, so I'll either pass it up all together, or chat to one of my 'solder-savvy' mates. Thanks again.

GW

I don't know if this is any help, but I repacked a 9.6V makita with batteries purchased from Dick Smith. They came with the little silver tags and where fairly easy to instal, you have to be careful to ensure there is nothing sitting between the batteries as there is no allowance when you refit the cap on the pack, but otherwise resin cored solder and a light iron should allow you to do the job, but using someone who has soldered before is not a bad idea. I got two years out of the new pack, and then one of the batteries failed.



JohnC

Accupak in Dural redone my batteries for $52. Fantastic value and the batteries are better than new.

Thanks again, guys, for your help. Wow! The mob at Dural are certainly cheap. Was that Panasonic 12v Ni-Cad? Cheers for that recommendation.

Almost all drill battery packs are built using common cell types. mostly "sub C"
so repacking is a proposition.
however
there are a number of importers who bring in aftermarket packs with reputable cells in them at a reasonable price.

if repacking the best option is to get the cells welded.

There are a number of suppliers who will do welded cell assemblies to spec. I few years ago I goat a batch done for a bloke who wanted to service motorola two ways. spec em sent em a sample & they came back just like the original, ready to go in the case.
sometimes it just easier to get a repacker to do it for you.
cheers