Newsgroups: sci.electronics
Path: cantaloupe.srv.cs.cmu.edu!magnesium.club.cc.cmu.edu!news.sei.cmu.edu!cis.ohio-state.edu!zaphod.mps.ohio-state.edu!caen!destroyer!cs.ubc.ca!mprgate!mprgate.mpr.ca!vanderby
From: vanderby@mprgate.mpr.ca (David Vanderbyl)
Subject: Re: Lead Acid batteries & Concrete?
Message-ID: <1993Apr23.225919.17278@mprgate.mpr.ca>
Sender: news@mprgate.mpr.ca
Nntp-Posting-Host: chip
Reply-To: vanderby@mprgate.mpr.ca (David Vanderbyl)
Organization: MPR Teltech Ltd.
References:  <C5y3A9.H8A@cmptrc.lonestar.org>
Date: Fri, 23 Apr 1993 22:59:19 GMT
Lines: 28

neal@cmptrc.lonestar.org (Neal Howard) writes:

>The concrete floor accelerates the problem because it is a heat sink and a
>colder lead-acid battery self-discharges at a slightly faster rate. That's
>why the old wives' tale of sitting it on a piece of wood on the floor works
>to help keep from killing the battery as fast ---- it insulates the battery
>thermally. It you'll set the battery down on a piece of styrofoam, it will
>self-discharge even slower.

There are a number of inaccuracies here:
1) In fact, a colder battery will self-discharge more slowly.  This is why
   batteries should be stored in a COOL, dry place.
2) An battery placed on concrete does not become colder than one placed
   on wood.  The battery, the wood, and the concrete will all be at the
   same general temperature (ignoring temperature fluctuations) and thus
   none will effect the other.

>The best thing would be to attach a small load
>such as a small transistor radio with the volume turned down low and leave it
>on constantly, but also trickle-charge it every couple days too to "shallow-
>cycle" the charge in the battery. Such mild "exercising" of a lead-acid
>battery is the next best thing to completely removing the electrolyte for
>storage.

There is no need to 'exercise' the battery.  Just keep it charged.  (A trickle
charger will do the job.)

[stuff deleted]
