Geoff

We used to set up and test computers for a charity which had projects in 26 African countries. Some of them used 12v car batteries with their solar power systems and wanted to run their laptops off these.

After some investigation and trials, we found that 240v battery to mains converters actually worked very well and quite efficiently. Attaching them directly to a battery (or via the cigarette lighter attachment, though they mostly didn't want this) was very straightforward.

We supplied about 20-30 of them in all, over a period of about 5 years, and there was never a problem, so I'd be inclined to recommend this method.

:-)
Ian