"John Horner" <jthorner@yahoo.com> wrote in message
news:BgdGe.10564$6M3.6708@trnddc03...
> flobert wrote:
>
>> Yes and no. The battery is designed to be chargable. using, and
>> draining and charging the battery doesn't 'damage it' per se. If it is
>> kept below 10V for an extended period of time (say 12 hours or more)
>> then it is irreperably damaged. using a trickle charger is the best
>> way to charge a low battery.
>
> Au contrar, cycling a battery, especially cycling it into a deep discharge
> mode, absolutely is a major factor in it's expected life time. Automotive
> lead-acid batteries do not recover well from deep discharge events.
> Take almost any new conventional battery and run it through twenty cycles
> of 90% discharge followed by full recharge. Most will be dead by the end
> of such a torture test.
>
> John

More on that and the heat issue on William Darden's great battery site
http://www.uuhome.de/william.darden/carfaq12.htm

(The Interstate Battery map he has agrees closely with my Phoenix
experience, too: 30 months.)

Mike