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HP Forum Archive 07

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HP charger with different cells?
Message #1 Posted by Ian Primus on 10 Jan 2002, 7:14 p.m.

I have a dead Woodstock style battery pack that I plan to rebuild, and I got it apart and removed the old cells, and bought some new ones at Radio Shack. I opted for the HI-Capacity Rechargeables, which are 1,000mAh as opposed to the 700mAh on the "Replace-a-cell" sets. Once I get the cells soldered together and re-inserted in the battery pack, how can I charge them? I have the HP AC adapter brick, as well as a separate little charger that just has a little light on it, and I have been using that for my other pack, but what happens if I use a pack rebuilt with these "High-Capacity" batteries? Will it just take longer to charge, or will it damage the pack/charger? Can I use this same charger if I were to replace the cells with NiMH ones instead of NiCad? Thanks.

Ian Primus ian_primus@yahoo.com

      
Re: HP charger with different cells?
Message #2 Posted by Vieira, Luiz C. (Brazil) on 10 Jan 2002, 10:59 p.m.,
in response to message #1 by Ian Primus

Hi;

I am sure a technical explanation will come soon, but I would like to take the matter to clear one fact. All woodstocks I saw oppened had the big 1/2 Watt resistor and a diode built at the right side of the main board. Are those the only componentes dedicated to the battery charging procedure? I did not follow the copper trails, so I do not actualy know if the PSU acts when batteries are charging.

Anyway, in both cases, the NMH or the NiCad batts will be current-limited. The little bricks will not be so much in pain, I guess.

Cheers.

      
Re: HP charger with different cells?
Message #3 Posted by Yani on 11 Jan 2002, 6:54 a.m.,
in response to message #1 by Ian Primus

If I understand your question correctly you are asking if the cell capacity makes a difference when charging.

The only difference is the time taken to charge. When replacing cells it is perfectly safe to go for higher capacity cells. The only possible gotcha is if the charger is a fast charger the cells must be able to take the charge current. However I think that most HP chargers are slow chargers.

Let me know if you want more detail. I could probably go on forever!

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