Another metaphor would be inflating a tire to 32 lbs with the compressor 
pressure set to 32 lbs.  Once the tire is full the air will stop flowing.  

From: Forrest Christian (List Account) 
Sent: Wednesday, June 7, 2023 11:58 AM
To: AnimalFarm Microwave Users Group 
Subject: Re: [AFMUG] battery overcharging

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 milliohms. 
 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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