On Fri, 7 Aug 2015 06:56:04 +0100, Brian-Gaff wrote:

Would not a simple silicon diode stop discharge though the cells?

The PV Panel already has a diode. Pretty sure I measured the leakage
and decided it was significant, FSVO "significant". I can't say I can
support that idea now, the specs for the 1N400? series of diodes give
a leakage of 10uA max, or 0.08 AHr/year...

--
Cheers
Dave.