RE: Battery Chargers, Pulse Units

[roden ald net]

Christopher Meier <Christopher Meier cwix com> wrote:

>  was under the impression that the pulse chargers use a much
> higher freqency than 120hz, and that the frequency isn't fixed,
> it varies.  I don't have the knowledge to know if that makes
> any difference.
> 

Hmm, I thought it was *lower*.  I don't know *why* I thought that, 
though.  You are probably right.  In any case, they do claim to have a 
more controlled effect.  And as I say, anecdotally, they seem to have 
an effect in certain circumstances.

One thing I thought of.  The pulsers are supposed to help sulfated 
batteries recover capacity.  I can see how they might have an effect on 
the crystalline lead sulfate that remains on the plates, but at least part 
of the capacity loss in old batteries happens because that sulfate 
*doesn't* stay on the plates.  It flakes off and falls to the bottom of 
the 
cell.  So the plates *permanently* lose active material, and if the layer 
of lead sulfate gets high enough, it can partially short out the plates.  

A pulse unit *may* be able to reconvert sulfate that remains on the 
plates (though I don't quite understand how), but there is no way for a 
pulse unit, or anything else I know of, to restore the lost active 
material.  

You can alleviate the shorting by draining the battery, rinsing it, and 
refilling with fresh electrolyte (though disposing of the old electrolyte 
and rinse water is a concern -- it's toxic waste).  This by itself can 
sometimes restore significant capacity to an old battery.

I'd be curious to learn whether a pulser can accomplish as much as 
this inexpensive but messy procedure, and how long the pulser's 
effects last.  Maybe both methods in combination would be useful.

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