I wonder if some form of solar thermal battery made from in situ resources would be effective for a moon base. 6.5 days in sunlight is a long time to get a larg

I wonder if some form of solar thermal battery made from in situ resources would be effective for a moon base. 6.5 days in sunlight is a long time to get a large mass nice and hot and you don't have a problematic atmosphere (or wildlife) to deal with. Not trivial, but I wonder if it would be cost effective than sending up reactors or nuclear batteries.