Ignoring the overvoltage for a minute..

A normal battery,  when charged at a normal voltage, will take less and
less current until full.   It doesn't matter how much current is available,
it will only take what it needs.   Generally you want to limit the current
based on the size of the array,  but that's for the start of charge, but
the end of it.   That is,  an empty battery array will take all the current
you can give it,  and too much can cause damage to the battery and maybe
wiring.

As far as the overvoltage goes, that's far more dangerous as overvoltages
tend to cause "boiling" of the battery which is just another way to say
that the battery is producing lots of hydrogen and oxygen which can cause
explosive atmospheres around the battery, or in an extreme case can cause
sulphuric acid steam to escape the battery.    Combine this with no
overcurrent or time limit and at the bare minimum you should expect swollen
and destroyed batteries.

On Wed, Jun 7, 2023, 1:05 PM <dmmoff...@gmail.com> wrote:

> So I was looking at a rectifier config and trying to imagine the worst
> possible thing I could do.
>
>
>
> With some creativity I could start an equalizing charge that will run for
> 48 hours at 58.5 Volts.  Normally it would stop when charge current hits a
> configurable fraction of the C10 Ah rating of the battery, but by
> intentionally misconfiguring the size of the battery and that fraction of
> Ah I could ensure that the equalizing charge runs until the maximum time
> limit…..which I can set as high as 48 hours.
>
>
>
> I could also disable the battery current limit, disable the over temp
> shutoff, and disable the temperature compensation.
>
>
>
> If I’ve disabled the current limiting feature in the rectifier, what
> determines the current that will go into the battery when I’m on a constant
> voltage charge?  The charger can do up to 100A, but would it put 100A into
> the battery for the full 48 hours, or would some other factor limit it?
>
>
>
> The spec sheet for the batteries lists an internal resistance of 3 
> *milli*ohms.
> V=IR tells me they could take thousands of amps at 58.5V.  Is there any
> other limit here besides resistance.  If nothing else stops this machine
> from dumping it’s full 100A into the batteries for 48 hours I’m pretty sure
> I could start a fire or explosion with this rectifier if I wanted to. I’m
> not trying to commit an act of sabotage by the way, I’m just wondering if a
> creative idiot could do something terrible.
>
>
>
>
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