Thanks for posting your experience with the Blue ESR Meter, Fred.

Keeping notes on various measurements has been a regular habit of mine
almost any time I'm testing or evaluating.

I think I know whatcha mean Fred, about not being sure exactly what the
readings indicate.
There sure won't be any numbers on a new battery regarding what the internal
resistance should be.

For decades, all I ever heard about any lead/acid battery's state-of-charge,
was specific gravity readings from a hygrometer.

Then a few years ago, I noticed an off-grid guy talking about the internal
resistance of LA batteries being a significant indication of the general
condition, or the amount of useable capacity remaining in used batteries he
was scrounging.
His remarks and others who also depend upon battery power because they're
off-grid, gave me the impression that they were seriously interested in
being able to gage and monitor their batteries.

The other point of his website was concerned with desulphator circuits he
had built to recover servicable life from used heavy duty commercial
batteries he could get for free.

So, as I did more looking for info regarding battery internal resistance, I
discovered that many others were interested in the IR of all types of
batteries.
Lots of reading, but no explanations that I could find, of how those folks
were determining the IR.

--
Cheers,
WB
..............


"Fred McKenzie" wrote in message
...
In article ,
"Wild_Bill" wrote:

I remember reading the comments regarding the use of the Bob Parker ESR
meter for checking battery IR/ESR quite some time ago, John, and also
Bob's
own descriptions of his circuit.

I have used the Anatek Blue ESR Meter with various cells and batteries,
including the 12 volt lead-acid battery in my car. The problem is that
I don't know how to evaluate the readings.

If you are going to use that technique for battery measurements, I'd
suggest building a library of measurements of cells in various states of
charge. It would probably work for both NiCd and NiMH cells, unless one
of them happens to have a resistance below the meter's limit. In my
limited experience, the cells were all within the meter's range.

Fred