Dave VanHorn wrote:

A sealed lead acid battery. Like in airplanes.


I suspect that having the word "aircraft" on the case will cost me dearly.

What would that equate to in terms of something I might find at battery
masters, or the inexpensive section of batteries plus?


I would never use an aircraft battery for anything other than in an
aircraft. For weight savings aircraft everything is made as light as
possible consistent with safety and operation. Light weight and battery
capacity are completely at odds with each other.

Dave WD9BDZ