Hi David,
We have recently developed hybrid refrigeration (
http://www.technet-21.org/en/forums/a-new-solar-hybrid-refrigerator-freezer) which can provide refrigeration, ice pack freezing and energy for lights, cell phone charging, etc.
Batteries can provide long life and trouble free operation. The key is to consistently shallow cycle the the batteries. A battery which can supply 600 cycles at 80% discharge can supply 6,000 cycles at 10% discharge. In our Sun Frost FRH-3 as a consequence of the high efficiency of the battery powered refrigerator compartment and the oversized solar panel even a battery as small as 40 amp hours will always be shallow cycled.
After about 10 years of operation the original battery could be replaced with a locally available inexpensive battery, it would still be shallow cycled and could provide about 3 years of service.
I hope another possibility does not cloud your decision making.
Sincerely,
Larry Schlussler, Ph.D.