HP 94 Battery Pack



#3

I suspect that my HP 94 battery pack has some dead cells. I wonder if anyone else has opened one of thses packs before? I would rather not do any more damage than is necessary. The case may split easily, but I am going to hold off, in hopes that someone else may have more information.

Katie, have you had to deal with this problem yet?


#4

I've rebuilt a couple of 94 battery packs, they take some time.

The way I did it was to peal off the rubber grip, cut out a large section of the housing where the grip was using a tiny Dremel circular saw. Then I replaced the cells with 4 AA ni-cads because it was too hard to fit the original 2/3 C cells into place within the opening that I cut. Finished by gluing the removed section back into place and put the rubber grip back on. I used carpet tape to put the grip on with, it's a really sticky double-sided tape and exactly the right thickness.

The packs look untouched when completed because the rubber grip hides all the ugliness.


#5

Quote:
The way I did it was to peal off the rubber grip, cut out a large section of the housing where the grip was using a tiny Dremel circular saw. Then I replaced the cells with 4 AA ni-cads because it was too hard to fit the original 2/3 C cells into place within the opening that I cut. Finished by gluing the removed section back into place and put the rubber grip back on. I used carpet tape to put the grip on with, it's a really sticky double-sided tape and exactly the right thickness.

I guess you are telling me the case is somehow heat staked or heat sealed, so cutting is the only option? My preliminary inspection led me to this conclusion but I was hoping for a miraculous cure.

Thanks for the information. It will be a back burner project. I can power it up with a lab supply for the time being if necessary.


#6

Yes, cutting seems to be the only option in the 4 battery packs that I've seen. Clearly they were assembled in two halves with a longitudinal seam, but I have been unable to open them along this seam.


#7

Did you cut the front face, back face, right side, or all of the above?


#8

I cut out pretty much the entire area underneath the rubber grip as just one large u-shaped piece.


#9

That was my plan.

Once again, thanks for the information.

#10

HP 94 ?
I don't know. Some site on her?

#11

What about this?


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