Lithium battery "refill" business

would

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managed.

machines.

I've done it before to fix a pack I needed right away with mixed results. I was never able to get the pack to look perfect again after cracking it open, and welding wires to batteries is extremly tricky without the right tools but it did work. I suspect you'd have a hard time making any sort of living off it but if you enjoy tinkering you might make a few bucks on the side to pay for your hobbies.

The trouble is that replacement cells of good quality usually cost more than a complete battery for the most common things like cordless drills, phones, etc. Although they will often make a cheap tool work rather better than new ;-)

You have two options. Maker's packs have welded connections - the heat generated by slower soldering may damage them. But so called tagged cells are available in the common sizes, and these may be soldered. The casing can be simply glued - if you can open it in the first place.

The main problem is that any maker of the things that use this type of battery buys them by the millions and gets bulk discount. You'll be buying only a few at a time - given the vast range - and will have to pay many times their price. So will really be limited to economic repair of specialist types where the overall sales are low.

| New Li-Ion batteries are super cheap on Ebay; under $40 For most high | capacity 7.2V models. I doubt you could remanufacture used ones for less.

Under $40 is super cheap?

Of course, I'm not even sure what application we're talking about. Small bare LiPo cells are relatively cheap, but the larger ones are quite expensive.

I do rebuild many of my own battery packs, but it's too labor intensive to try and make a living at it.

I did replace the Li-ion battery in my iPAQ with an R/C LiPo battery for about $10. To buy the battery elsewhere would be about $40. Works fine now. So it definately worked well for me, and I rebuild NiCd packs for radios all the time, usually with NiMH cells with a lot more capacity. But it takes a lot of time ...

You MUST have a spot welder to connect the cells. DON'T LET ANYBODY TELL YOU OTHERWISE!!!!! You MUST have a LOT of insurance. If anything you ever touched catches fire or if someone's laptop dies for ANY reason, you'll be getting a call from some nice lawyers. You MUST have proprietary information from the equipment vendor. Some/many battery packs lose their brain when you disconnect the cells.

Nobody is ever happy with their device battery. Last place you want to be is in the middle. "Battery pack can't be repaired." "Whaddya mean, it worked when I sent it to you?".....

Suggest you find a simpler business with less legal downside and fewer customer issues. mike

Thank you all. It's very informative...

SY Chun

| You MUST have a spot welder to connect the cells. DON'T LET ANYBODY | TELL YOU OTHERWISE!!!!!

Here, I'm going to tell you otherwise.

Sure, it would be nice -- it would make the job a lot quicker, which would be important if you wanted to make a business out of it.

But you can certainly solder your own battery packs together, and once you get the hang of it, the odds of a bad pack are very low.

The key is to have a hot soldering iron -- 80 watts or so -- and to be very quick -- no more than 3 seconds of heat on the battery. More, and you risk damaging the cell. Typically I glue the cells together, use a dremel on the tips to make them rough and to clean them up, tin them with solder (< 3 seconds each), then use desoldering braid to solder the cells togeter (again, < 3 seconds each.) Once done, I throw it on the battery cycler and make sure that the pack's performance is what it's supposed to be. If not, I throw the pack into the `recycle it' bag.

I've made lots of them -- for radios, for R/C planes and transmitters, for power tools, and have not had any problems beyond a small percentage (10% ?) not making the grade once I ran them on the cycler.

If you're afraid of soldering directly to the battery itself, you can buy cells with soldering tabs, but I find it's easier to do it without them, and you'll pay extra for those cells (certainly, you won't find them on sale at Frys or Harbor Freight Tools for under $1/cell for AA cells.)

| You MUST have a LOT of insurance. If anything you ever touched | catches fire or if someone's laptop dies for ANY reason, you'll | be getting a call from some nice lawyers.

Probably true. I certainly wouldn't rebuild somebody else's laptop battery for them, but I might try it for my self.

| You MUST have proprietary information from the equipment vendor.

This will depend on what you're doing. Certainly, most NiCd/NiMH packs use AA, AAA or subC cells and there's nothing special you need to know there. But for the LiIon and Lipo packs, there may be something special you should know. (And abusing these packs can cause fires -- very bad.)

I know you mentioned LiIon cells specifically, but if you were to get into the business, I suspect you'd be doing NiCd and NiMH batteries too ..

| Some/many battery packs lose their brain when you disconnect the cells.

I've never run into that problem, though I don't doubt it exists. I've even rebuilt some LiIon packs with good results, removing the circuitry on the pack and putting it on a similar LiPoly cell. It's not really pretty, but works well. The LiPoly cells I've bought had solder tabs, which was nice.

| Nobody is ever happy with their device battery. Last place you | want to be is in the middle. "Battery pack can't be repaired." | "Whaddya mean, it worked when I sent it to you?"..... | | Suggest you find a simpler business with less legal downside and fewer | customer issues.

Probably good advice. But for your own use, rebuilding packs is a great way to save money.

I just love it!!!!

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There you go. 10% INITIAL failure rate. That's sure the way I want to run MY business....

this is just nuts!!!

The above is the most telling part of your whole soldering suggestion. Somehow I thought that rebuilding someone else's pack was necessary to have a business...soldering is NOT acceptable.

If you listen carefully, you can hear the sound of me beating a dead horse... mike

| Doug McLaren wrote: | > In article , mike wrote: | > | > | You MUST have a spot welder to connect the cells. DON'T LET ANYBODY | > | TELL YOU OTHERWISE!!!!! | > | > Here, I'm going to tell you otherwise. | | I just love it!!!!

I thought you might.

| snip | > But you can certainly solder your own battery packs together, and once | > you get the hang of it, the odds of a bad pack are very low. | snip | > I've made lots of them -- for radios, for R/C planes and transmitters, | > for power tools, and have not had any problems beyond a small | > percentage (10% ?) not making the grade once I ran them on the cycler. | | There you go. 10% INITIAL failure rate. That's sure the way I want to | run MY business....

You may not have read my post very carefully, so I'll reiterate the really important part -- I wouldn't want to make a business out of it. It's too labor intensive. I've already said that a few times, but there, I've said it again.

As for the 10% failure rate, that's the number of packs that don't cycle to their rated capacity. It could be that I ruined a cell, or there was a cell bad to begin with, or I just didn't form the pack properly (which is easy enough to fix), but unless I'm pretty convinced that a pack is good it's not going up in an R/C plane. (I might use it in a cordless phone or something, however.)

But I'm perfectly happy with not using a spot welder for my packs. Things work quite well most of the time.

I also tend to use the cheapest batteries for non critical applications (power tools, cordless phones, etc.) -- 700 mAh AA NiCd cells from Harbor Freight Tools for $0.60/cell? Pretty cheap! I'm not surprised if most of the failure rate is the fault of that.

For R/C packs, I prefer to get cells for a somewhat more reliable source, and cycle them a few times before I use them -- the consequences of a failure are higher there.

As for the 10% initial failure rate, once I get past that, I've found that the failure rate is not really any different than cells that I've bought at full price from people with spot welders. Batteries don't last forever, and mine aren't any exception.

| > If you're afraid of soldering directly to the battery itself, | | this is just nuts!!!

FUD often is. It's perfectly possible to make good battery packs without a spot welder.

| > Probably true. I certainly wouldn't rebuild somebody else's laptop | > battery for them, but I might try it for my self. | | The above is the most telling part of your whole soldering suggestion.

Laptops cram lots of little LiIon cells in there, with wierd sizes (read: hard to find) and then they have more circuitry than anything else to deal with. And if something fails, it could ruin an expensive laptop. I'd risk my own laptop, but probably not somebody else's.

I don't have special insurance. (Remember, it's not a business.)

| Somehow I thought that rebuilding someone else's pack was necessary to | have a business...soldering is NOT acceptable.

Again, I was just giving my personal experience -- I've probably made at least 50 battery packs of various sorts by now. I've only done a handful of LiPo packs, however, and found them to be harder to deal with.

No, it's not a business. I wouldn't want to make a business out of it

-- the pay per hour would be too small to be worth it. But when I rebuild a battery pack that would cost $40 for $6, I feel good about it, even if it all took 30 minutes.

Now I've lost track ... how many times have I said I've not made a business out of it, how many times have I said I don't want to make a business out of it? Hopefully enough times.

| If you listen carefully, you can hear the sound of me beating a dead | horse...

That's nice.

Hmm. I've found the poor performance of cheap cordless power tools to be more down to poor quality original cells than the motor or control gear. Substituting Sanyo cells can sometimes bring the performance more inline with a decent quality one. Like far better - and controllable - starting torque in screwdriver mode, etc.

It takes a skilled refiller-shop with a spot welder, microwave sealer, and cell stock at least 30 minutes to do the job on a typical known (to the shop) laptop pack. A low-middle income living at best if in a relatively low wage market with high laptop penetration. That's assuming easy bulk cell supply, and as pointed out here, no personal and liability insurance worries. There's also the fact not all pack electronics will show the new capacity correctly to factor in.

Thanks H!