I have made notes of all of the battery and starter incidents for a few years now. Not only my own but from others sharing on this site, and there have been some lengthy and plausable explanations further;
I have spoken at length to Keith at BHM, the Richard Thorne team, Techniques and Brian Miller all of which have a considerable weight of experience. Tried new batteries, battery testing kit, new starter motor, issolated the power, brought in witch doctors, however I am no nearer an explanation than when I "started". On the upside, it has always lit when required {4 years].