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How to get inside a Thinkjet Battery???
Message #1 Posted by Steve on 19 Nov 1999, 7:35 a.m.

lots of battery questions tonight...

I have an HPIL HP225B, and the battery pack has resisted my efforts to get inside.

It seems like a couple of clips will do it, but it won't play ball.

Incidentally, the HP225B looks like it was manufactured so that dry cells may have been a power option...

      
Re: How to get inside a Thinkjet Battery???
Message #2 Posted by Joe on 19 Nov 1999, 7:50 a.m.,
in response to message #1 by Steve

I guess you could use dry cells in it but it would get expensive to operate since dry cells aren't rechargeable.

The ThinkJet battery uses 6 sub-C NiCads. (rechargeable).

To open it, first look at the sides and note the two pegs sticking out near the top. You have to release them to get the top off. OK, ready. Remove the two screws in the top. Then pry the sides away from the top to free the pegs the stick in the holes in the side and pry the top up. Sometimes it's hard to get the top off the first time since they put double sided tape under the batteries and on top of them. That glues the batteries into the case and glues the top to the batteries. You'll also have to push the release latch in for it to clear the top edge of it's opening.

Joe

            
Re: How to get inside a Thinkjet Battery???
Message #3 Posted by Steve on 19 Nov 1999, 8:06 a.m.,
in response to message #2 by Joe

Hmmm, that sounds just like how I got into the 9114's battery pack (right down to the release latch).

My pack for the thinkjet has no obvious screws, and no stickers to hide them under. The release latch pulls off.

Under where the release latch is there are two tabs. Releasing these looks like it should release the top cover (also releasing the side pegs) but is stays stubornly intact.

If you're sure about the glue, I could try harder :-)

                  
Re: How to get inside a Thinkjet Battery???
Message #4 Posted by Dan M on 19 Nov 1999, 10:59 a.m.,
in response to message #3 by Steve

The Thinkjet battery packs I have opened have all been held together by the tabs (obvious) and by some very effective double-sided-sticky tape inside the package. My suggestion to you is to continue to "try harder." There are no hidden screws or additional snapping latches, just some really sticky old tape...

Once you can get it started it goes pretty easily.

                        
Sould I replace the cells?
Message #5 Posted by Steve on 19 Nov 1999, 6:25 p.m.,
in response to message #4 by Dan M

That stuff is certainly sticky, and the cover gets an awful bend on it while you're removing it, but it sprung back and doesn't seem to have sufferred any lasting damage :-)

Just as I feared.....

Whilst the pack holds a charge, one of the cells has started to exude its contents slightly.

The electrical characteristics of the cell seem to be curently unchanged.

Should I replace all six of the cells now? Or wait until it gets worse?

Oh, and I covered the sticky stuff with paper so the top will come off easier next time.

But the cells themselves seem to be stuck down really well too. Is it more tape? or is it worse...?

                              
Re: Sould I replace the cells?
Message #6 Posted by Joe on 20 Nov 1999, 9:56 p.m.,
in response to message #5 by Steve

Steve,

YES! Replace all the batteries. If you mix old batteries and new ones the old ones will soon fail.

Yes, there's more tape under the batteries. Don't worry about putting paper between the top and the tape, once you break it loose it loses most of it's stickiness.

Joe

                                    
Re: Sould I replace the cells?
Message #7 Posted by Yos Feit on 22 Nov 1999, 8:44 a.m.,
in response to message #6 by Joe

I found that the cost of 6 sub C cells with the solder tabs was very close to the $60 charged by HP for a replacement pack. How much are you paying for the replacement cells?

                                          
Re: Sould I replace the cells?
Message #8 Posted by Steve on 24 Nov 1999, 3:07 a.m.,
in response to message #7 by Yos Feit

About $US5 per cell (2/3 C cell).

If that $60 is $US60 for a replacement then replacing the 6 cells seems like the economical option.

                                                
Re: Sould I replace the cells?
Message #9 Posted by Joe Sullivan on 27 Nov 1999, 11:01 p.m.,
in response to message #8 by Steve

Several months ago I found a new HP 82199A rechargeable battery pack in a box of HP stuff that was given to me. I believe it's for the Thinkjet printer. Let me know if anyone is interested.

                  
Re: How to get inside a Thinkjet Battery???
Message #10 Posted by Joe on 20 Nov 1999, 9:52 p.m.,
in response to message #3 by Steve

Steve,

Oops, you're right. I was looking at a 9114 battery. The ThinkJet battery case is the same but it doesn't have any screws. You'll have to pull hard to get the top free of the tape. You may try reaching under the to with a long thin knife and cutting through the tape.

Joe


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