Odyssey PC 680 battery
The battery weighs only 7 kg compared to the old one of 15 kg's. It is a dry cell battery so you do not have to worry about acid leak and all the other hazards normal batteries have. I was surprised at how small the battery was - about half the depth of a standard battery.
I have made a suitable enclosure in aluminium and relocated the battery to the front of the passenger foot well.
Voltage: 12 V
Capacity: 16 Ah
Cold Cranking Ampere (CCA): 210 A
Pulse Hot Cranking Ampere (PHCA): 680 A
Length: 181 mm
Width: 76 mm
Height: 167 mm
Weight: 7 Kg
Terminals: Female brass with M6 SS bolts
Storage life: 2 years
This battery does not lose its charged energy during cold storage temperatures, so there is no need to trickle or float charge during winter months. To store off-season, measure the battery voltage to make sure it is fully charged, 12.84 volts or greater; recharge if nessesary. Disconnect the negative battery cable to prevent any applied electrical load during storage.
The optimal charging voltage is between 14.2 and 15 volts.
Odyssey recommend an automatic charger that would bring the battery up to 14.5V then switch to a float (trickle) voltage of 13.6V; it will stay at that level indefinitely.
Good technical reference is here