[Shop-talk] Solar-powered battery charger for generator?

[Doug Braun]

Hello,

My parents have a backup generator for their house. 
Unfortunately any time they want to use it, the
starter battery is dead, and they're not up to
pull-starting it.  My first thought was to get an
ordinary battery maintainer and hook it up, but
unfortunately the generator is in a garden shed, and
there is no power feed to the shed, only the generator
output line from the shed to the house.

It seems like a solar-powered battery maintainer would
do the trick, but I need to find one that has a solar
panel that can be mounted on the shed roof, and has a
charge-controller circuit that will keep the battery
in good condition for months at a time.

I have seen the type of solar charger that you put on
your car's dashboard and plug into the cigarette
lighter, but I really need something better.

Any suggestions on where to look?

Thanks,

Doug