I use a pair of huge, heavy duty 6 volt batteries - wired to to give 12v output - been using them for 18 months plus and always left on charge overnight, still going great guns and on charge overnight, every night.
On my backpack/trolley (shopping trolley
) I have an 80 ah car battery and that ids also left on charge overnight.
Both batteries on an intelligent charger and most of the time both are fully charged by the morning.
I'll be interested to know how long the car battery lasts; oh, and both batteries are going full bore several hours a day.
In the past though I've found they only last about a year or so...maybe because I tend to buy budget ones?
I'm thinking that perhaps if the van mount ones are connected to a split charge relay they will last many times longer, which would certainly offset the cost of getting one fitted...
My van battery had to be replaced the other day, I've given Squeaks it now as a backup battery, and I'll be interested to know how well it lasts him compared to the one that now only gives him 3 hours use a day, especially as it is now too duff to be used as a van battery...but it is a heavy duty one.
It may well be too knackered to be of any use to him...I'm going to be very interested to find out how it performs...
Ian