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From: piglet <erichpwagner@hotmail.com>
Newsgroups: sci.electronics.design
Subject: Re: Battery (SLA) modeling
Date: Fri, 13 Dec 2024 23:15:35 -0000 (UTC)
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john larkin <JL@gct.com> wrote:
> On Thu, 12 Dec 2024 23:57:54 -0700, Don Y
> <blockedofcourse@foo.invalid> wrote:
> 
>> At a fixed time and temperature, is it safe to model a battery as a
>> fixed voltage source behind a series resistance?  Possibly, additionally,
>> a parallel RC to cover transients?
>> 
>> In particular, does the model need to change based on whether the
>> battery is being charged or discharged?  (i.e., to estimate that
>> series resistance)
> 
> I've wondered about electro-chemical time lags, ions drifting around
> in liquids, as in what would the Spice model of some battery be? And
> on a slower time scale, the morphology of a battery changes with time.
> Nearly discharged batteries sure go Hi-Z.
> 
> What we need here is a good physical chemistry guy.
> 
> 

Yes I have noticed SLA can exhibit an initial voltage sag far longer than
can be explained just by internal resistance- I assumed some kind of
stagnant electrolyte layering effect?


-- 
piglet