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HP Forum Archive 16

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82143A Battery
Message #1 Posted by Christian Felsing on 14 Jan 2007, 3:47 a.m.

Hello,

I would like to build a new NiCad Battery pack for HP82143A printer. I do not have an original pack, so I do not know which voltage is expected by 82143A. Does anybody have some technical data regarding 82143A batteries ?

regards Christian

      
Re: 82143A Battery
Message #2 Posted by Eric Smith on 14 Jan 2007, 5:39 a.m.,
in response to message #1 by Christian Felsing

It uses four NiCd cells. You should probably use four NiMH cells instead, though.

            
Re: 82143A Battery
Message #3 Posted by Les Wright on 14 Jan 2007, 9:04 a.m.,
in response to message #2 by Eric Smith

Eric, Mark Hoskins argues in his listings for his packs that NiMH packs are prone to overcharging. How accurate is this statement? I got one of his packs for my printer and like it, but must admit I would prefer to use longer laster and less environmentally nasty NiMHs when I can. I use two NiMHs in my HP33C and it works well even though the fit is rather snug and one of the contact tabs is broken because of it.

Les

                  
Re: 82143A Battery
Message #4 Posted by David Smith on 14 Jan 2007, 11:43 a.m.,
in response to message #3 by Les Wright

All batteries are prone to overcharge in the HP-97. It dumps quite a bit of current into the pack. For longest life you should not leave the thing plugged in all the time. Since NiMH cells have over twice the capacity of NiCads, the charge rate versus capacity rating is half (i.e. if it charges a nicad at C/8, the NiMH pack would be more like C/20). Battery manufacturers state that a C/15-C/20 continuous charge rate is OK for NiMH cells. I have used NiMH cells without problem in HP-97's (and I'm too lazy to unplug the thing when it is fully charged).

      
Re: 82143A Battery
Message #5 Posted by Les Wright on 14 Jan 2007, 8:48 a.m.,
in response to message #1 by Christian Felsing

The 82143A and HP97 use the same type of battery. I recall Katie Wasserman mentioning to me in another thread about a shorted HP97 battery that a good, fully charged pack should give about 5V.

Les

      
Re: 82143A Battery
Message #6 Posted by Les Wright on 14 Jan 2007, 8:53 a.m.,
in response to message #1 by Christian Felsing

The photo here shows quite well the cells that Mark uses--1.2V, 1000mAh in this picture, but the latter criterion seems to vary as I just go a pack from him made with 1500mAh cells.

            
Re: 82143A Battery
Message #7 Posted by Christian Felsing on 14 Jan 2007, 9:37 a.m.,
in response to message #6 by Les Wright

Thank you for advice. I will try 4 AA cells each 900mAh, which match original cells best and AA cells are really cheap. Charger is made for NiCd cells, so NiMH cells are not suitable.

best regards Christian

                  
Re: 82143A Battery
Message #8 Posted by Dia C. Tran on 14 Jan 2007, 12:03 p.m.,
in response to message #7 by Christian Felsing

I use 4 sub C 3000mAH NiMH cells. I charge them for 48 hrs or so. They last much longer than the original pack.

                        
Re: 82143A Battery
Message #9 Posted by Les Wright on 14 Jan 2007, 4:43 p.m.,
in response to message #8 by Dia C. Tran

I am surprised that no one has devised a housing or chassis of sorts that a takes 4 standard size AA NiMH batteries. On the underside of the chassis would be the two exposed terminals that would make contact appropriately with the prongs in the bottom of the battery compartment. The chassis would have to be large enough or appropriately padded so proper contact is maintained--Mark Hoskins uses some sort of foam rubber on his packs for this purpose.

If the user is concerned about overcharging in the 97, s/he could simply remove the batteries from the chassis and charge them in a proper charger for the purpose--goodness knows they are common enough. You could also have a spare set of AAs ready all the time.

I use 2600 mAh Duracell NiMH AAs in my 82240B IR printer, and I am really pleased with the convenience and the long life. I really wish I had similar convenience with my 82143A printer.

Les


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