I’m just dealing with the idea of installing a second battery in the spare wheel pit again. there’s the following question: 1. does the battery need cooling or doesn’t matter? I would probably build a board over there, then there would hardly be any air. 2. do I need a separation relay? what exactly is that? is this to recommend or doesn’t matter? where do I build it? 3. I have a 35 and a 20 cable in the car, the 20s would probably be long enough to reach the 2. battery to come, the 35s very probably not. is the 20s enough to connect the two batteries? 4. How to attach the battery best in the spare wheel pit? I would then probably take an exide maxxima DC, is there a better one for the money? does it need any special care? expand and charge or something?