NiMH Batteries@Z88

Discussion forums for users of the Cambridge Z88 Portable Computer
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cha05e90
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NiMH Batteries@Z88

Post by cha05e90 »

I was searching for some newer information regarding the use of re-chargeable nickel-metal hydride batteries (instead of the usual alkaline batteries). I could not find anything relevant except comments about the not-so-modern NiCd type of batteries (which don't seem to be recommended...).

Has someone gained any experience with NiMH batteries in the Z88?
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daveZX4th
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Re: NiMH Batteries@Z88

Post by daveZX4th »

I don't generally use NiMH in Z88 since the fall off in voltage is quite quick and unexpected compared to alkaline (IMHO). I just use Duracells whenever I have a session using Z88 and don't want lose anything if it is left idle for a while.
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cha05e90
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Re: NiMH Batteries@Z88

Post by cha05e90 »

Thanks for the info.

I did not knew that the NiMH batteries show the same rapid voltage drop than the older NiCd type. So I'll stick with standard alkalines then...
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Paul
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Re: NiMH Batteries@Z88

Post by Paul »

Did anyone try 14500 batteries in a Z88? They are rechargeable, exact size of an AA battery and have 3.6V. two of them plus two dummies (possible shorted or fitted with a diode) would give the needed 7.2 V.
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daveZX4th
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Re: NiMH Batteries@Z88

Post by daveZX4th »

Interesting idea, you would have to use a diode in each of two dummy cells to drop to around 6V to Z88. Without you could overdischarge Li-on cells below the 2.4V limit without Z88 battery low symbol showing.
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