NiMH Batteries@Z88

Discussion forums for users of the Cambridge Z88 Portable Computer
Post Reply
User avatar
cha05e90
Posts: 10
Joined: Mon Mar 14, 2022 1:31 pm

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?
48K/+/+/+/+128K/Vega/Next&80/81&88
daveZX4th
Posts: 16
Joined: Mon Dec 04, 2017 2:22 pm

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.
User avatar
cha05e90
Posts: 10
Joined: Mon Mar 14, 2022 1:31 pm

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...
48K/+/+/+/+128K/Vega/Next&80/81&88
User avatar
Paul
Posts: 1511
Joined: Thu May 27, 2010 8:15 am
Location: Germanys west end

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.
Kind regards Paul
In theory, there is no difference between theory and practice. But, in practice, there is.
daveZX4th
Posts: 16
Joined: Mon Dec 04, 2017 2:22 pm

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.
Post Reply