RE: (ET) 12 volt batteries

["Hazen, Dwight L" <hazen indiana edu>]

Jim,

 I too wondered about hydrogen gas production during high current 
discharge.
I figured if the battery exploded flammable gas had to be present as lead
and plastic are stable things. I do know when you battery test you are
always told to remove the battery caps and make sure the cells are covered
with water. I guess the bottom line is sparks around any wet cell battery 
is
not good. 

  Dwight 

Dwight L. Hazen, Indiana University, UITS 
Bloomington, In. 47408-7378 Phone 812-855-5367 hazen indiana edu
http://php.ucs.indiana.edu/~hazen/ Ham Radio wb9tlh arrl net
IP Phone 317.278.4014   Change is inevitable except from a vending machine.


-----Original Message-----
From: Jim Coate [mailto:jbc coate org] 
Sent: Tuesday, January 08, 2002 2:45 PM
To: elec-trak cosmos phy tufts edu
Subject: Re: (ET) 12 volt batteries


An alternate scenario: One of the 3 batteries had a very dead cell in it
(fully discharged). When running the ET up the ramp, the other batteries
forced current through the bad cell, it reversed, heated up, and boom.

Driving up the ramps, assuming in low or LL, should take less than 75
amps for maybe 30 seconds... something any decent car battery should 
handle.

David or someone may know better, but I don't think hydrogen is produced
during use, but rather only during charging (and only the final phase at
that)?


"Hazen, Dwight L" wrote:
> I can guess what happened with the temporary battery tractor move. High
> current draw from a small battery produced lots of hydrogen gas and a
loose
> battery connection caused a spark. Also if the water was not covering the
> plates it would have made a larger chamber for gas to collect, blowing 
> the
> top off the battery.
> 
> -----Original Message-----
> From: habooly earthlink net [mailto:habooly earthlink net]
> 
> I used 3 old  12-volt batteries to move my tractor up a ramp and one of
the
> batteries blew apart.
> They were automobile batteries, not deep-cycle.