On 15/10/2013 9:25 AM, Neil wrote:
> ... The reason
> for standard automotive batteries is that I have several.  If I find
> that I can safely use only say 25AH of a 50AH battery, then I can take
> two, etc.

 From experience, if the batteries are in good to great condition, the=20
automotive battery will discharge to 50%, but you will severely shorten=20
it's life, and then the next time it won't be 50% because the battery=20
won't have the same capacity available as gradually (sometimes quickly)=20
the battery looses available capacity. (you should as already stated use=20
Deep cycle batteries for this, an AGM type is best.)

It also depends on how long you are going to do this for as well, eg.=20
every day, every week etc.

The battery WILL let you down when you least expect it!

I have been there before multiple times and using automotive batteries=20
for powering anything standalone over a day can be problematic over time!

A voltage cut-off circuit set to about 11V to 11.5V, would help protect=20
the battery.

Recharging them ASAP and don't leave them sitting for any length of time.

It also depends on the actual battery you are going to use, as in the=20
specific brand plates and size etc, does in my experience make a=20
difference as well.


Peter

--=20
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