Re: [photo-3d] Nimh / NiCad / Alkaline

[Brian Reynolds <reynolds@xxxxxxxxx>]

Boris wrote:
> NimH and NiCads have much lower internal resistance than Alkalines.
> What does this mean?
> 
> Low internal resistance:
> Plus: cell can bear a much higher load, deliver more power (over
> shorter time).
> Negative: cells lose voltage immediately as they are discharged.
> 
> High internal resistance:
> Plus: cells keep voltage up near rated (1.5V) for most of discharge
> period.
> Negative: Alkalines are "stingy" with power.  They do not take high
> loads well.
> 

This goes against everything I've read and experienced.

As George has mentioned Alkalines do not maintain constant voltage as
they are discharged.  One of the great benefits of NiCads are that
they stay at the rated voltage until just before fully discharged
(which is why simple methods of determining charge (i.e., measuring
cell voltage) don't work, leading to overcharging and internal
damage).

-- 
Brian Reynolds                  | "Dee Dee!  Don't touch that button!"
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