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mike[_22_]

On 10/28/2012 3:48 PM, wrote:
I'm asking this question on here because I've read several times about
some of you rebuilding the battery packs for cordless tools.

Have any of you rebuilt the battery packs for laptop computers? Can
this be done? They want more than I paid for the computer for a
replacement, so it's either rebuild it, or replace the computer and just
use the old computer where there is an outlet.

It's a crap shoot.
Depends a lot on the technology and the vendor.
I've had zero luck with IBM. Once the "chip" shuts off, it's
all over.
Dells resort to an error condition, but the pack works.
Had one with a PIC processor...resetting the processor fixed it.
Others have no issues at all.
Got one that will charge, but the computer won't run on AC, it
defaults to battery. Only way to charge it is to leave it off.
Only way to run it on AC is to remove the battery.

You can buy software that claims to reset chips, but it costs
more than a new pack. And it requires some hardware.
Not clear if it's updated to the latest stuff.
I've never found resetting info on the web.

Where are you gonna get QUALITY new cells for less than the price of the
pack?

How are you gonna attach them? The fit is so tight in the plastic
that even tabbed cells are a problem. Where are you gonna put the
solder joint on the tab that still lets the case close.
I bought a tab welder that greatly simplifies the situation.

What are you gonna do about mismatched cells?

What are you gonna do when you pick the wrong cells and it
catches fire while your kid's surfing the web?
I've rebuilt several packs, but there's no way I'd sell one
in a used laptop. Liability risk is too high.

There are lots of how-to's on the web. Many resort to soldering
directly to the cells. That's a disaster waiting to happen.

I understand your pain, but unless you're rebuilding many
packs and are willing to invest in the equipment and training,
my advice is to give it up.

You can buy external batteries that plug in the ac adapter socket.
Not optimal, but they can work with different laptops.

Are we having fun yet?