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T i m T i m is offline
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Default Predicting a graph from 3 (6?) values?

Hi all and knowing there are some scientists / mathematicians walking
amongst us ... ;-)

I'm trying to see if there is a (rough even) way of measuring the
Depth Of Discharge voltage / cutoff point versus current load value
for a specific lead acid battery.

The manufacturers have provided me the following values (@ 50% DOD).

11.75V @ 93A (12.4V initial)
12.05V @ 18.2A (12.7V initial)
12.10V @ 4.65A (12.75V initial)

(The general chart starts at the values marked 'initial' so that would
be for those currents but at 0% DOD but I'm not sure if that is
relevant).

Now, it's obviously not a straight line (Peukert's law), but can you
extrapolate a graph (or create a formula that would be more useful for
my project) from just 3 points please?

Maybe Peukert's law itself would give those with a brain wired
differently than mine the answer? ;-)

https://en.wikipedia.org/wiki/Peukert%27s_law#Formula

Cheers, T i m

p.s. The nearest *I* could get to an answer would be some graph paper
and a Flexicurve. ;-)