On 10/07/15 14:19, robobass wrote:
I wouldn't run one off a car battery all night away from home because
they consume a fair amount of current internally and you might not be
able to start the engine in the morning.

-jsw
Right. I know mine is sucking power even when switched off. Where we're going I need to leave the car a fair distance from the tent and will be using a spare battery, mostly without the inverter attached. Still have to work out options for recharging in the morning...
You can buy brief case style folding solar panels for just this type of
application. I've seen then sold by Maplin in the UK and on ebay so
expect they'd be easy to find in Germany.