I’m currently facing a big problem. As I’m soon on the road I want to buy a “refrigerator” for the car. size, brand etc. are not important now. much more important is that I calculate with an average power consumption of about 40Watt. at 12Volt it would be about 3.5A Since I also want to park my car for a few hours, without having to bridge afterwards, I want to install a 2nd battery in the suitcase room. I already think about special circuits, e.g. that the box gets its own socket, which will only be supplied by the additional battery. now the question, can you easily install any battery? I have read something about gel batteries that may be installed in the car. my training master told me “at the time” that there is a PIN on the light engine, where you can control a relay so that the battery only charges when the engine is running. about inspirations and suggestions I would be very grateful, mfg, sergej