I have fitted a pair of odyssey batteries in my 110 which I got from Paddocks. I've found them to be good at everything from normal running about to heavy duty winching good all round battery although not too cheap.
Edward.
http://www.paddockspares.com/scp/OFF_ROAD/Odyssey_Batteries.html G4 110 BT52 CNK 03 Germany Ireland support vehicle South Africa 06 Bolivia support reccy vehicle only vehicle to carry kite surfer81 AM 79 / UNV 438REx RAF 101 Forward Control Radio body 1 of only 6 commissioned
Are all the windows fully up as mine would go off even when smallest amount open.
The alarm system ought to have a battery back up, though I seem to remember this was an option at one time but being CSW's could have been standard.
My battery monitor still shows in the yellow after a week of rest.
I didn't start my 110 from christmas to February this winter due to my broken ankle and it started first time. It was parked outside in the snow all the time alongside my Honda Civic which was completely dead.