Re: Battery (SLA) modeling

On 12/13/2024 8:57 PM, Bill Sloman wrote:

On 14/12/2024 4:23 am, john larkin 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?

 That's what Warburg impedances are about.
 

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.

 I've got a Ph.D. in physical chemistry, but batteries are electrochemistry - I know a guy who has just completed a Ph.D. with a thesis on a particular lithium ion battery chemistry. It's a specialised subject.
 

I guess not many universities offer a PhD in non-physical chemistry these days. :(