Whilst out camping last weekend, my leisure battery run low, which was not surprising as I was running the fridge, lights, Nintendo, laptop, mobile phone etc for 2 days.

Whilst driving home I thought the alternator would charge the leisure battery back up but when I got home after driving for over an hour the leisure battery was still very low.
I hooked up the leccy cable for half a day thinking the PMS unit would charge the leisure battery, but still no change.
My question is, what should charge the leisure battery?
I have an Elite side conversion with a PMS 3V fitted.
Thanks