David wrote:
> Battery life is directly related to how deep the=20
> battery is cycled each time. If a battery is=20
> discharged to 50% of capacity every day, it will=20
> last about twice as long as if it is cycled to=20
> 80% DOD. If cycled only 10% DOD, it will last=20
> about 5 times as long as one cycled to 50%

Mark wrote:
> There are a couple versions of Odyssey
> versions that fit without the damage you need to do to make an Optima
> fit in one of the sealed compartments like yours. I think the PC1200 is
> the best match. GoWesty even sells them. Not cheap.

I put in an Odyssey last summer as my aux battery.  It is a
PC925MJT.  It fits with room to spare--I had to cuts some blocks
to lock it in place so it wouldn't slide back and forth.  I
wish I'd gotten the PC1200 now; don't know why I didn't.

Not to argue with what David wrote, but Odyssey claims 400 cycles
to 100% depth of discharge.  Maybe "100% depth of discharge" has
a technical meaning other that what we would think....but see
http://www.odysseybatteries.com/
Anyway, I haven't run mine down to test this.

Richard
Boulder