..the math:

>and the battery has 6v x 225Ah = 1350watts.

>1350watts / 36 watts = 37.5 hours??

225Ah means AmperHours - that is the capacity of the battery (C=I*T). It does not indicate the max current you can draw out of it (it depends on the battery type).

So you may source 225Amperes for 1 hour long out the battery (if applicable

), or 22.5Ampers for 10hours, or 2.25A for 100hours.

The power P (in Watts) you can get out of the battery is P=U*I. So ie. while drawing 22.5Amp * 6Volt = 135Watt.

Or,

6v x 225Ah = 1350Wh

1350Wh / 36W = 37.5 hours