A leisure battery is an auxiliary power supply that's designed to provide your caravan/motorhome with a steady rate of power. This is the type of power you need to ensure the electrical system stays healthy. All leisure batteries in the Euro Car Parts range supply 12V of power. Yet the important unit to consider is ampere/hours (Ah). This is a measure of capacity (how much energy the battery can store). The higher the Ah of the battery, the longer it will last before you need to charge it. The battery size you choose must correspond with that of your battery box. This is because the higher the capacity of a leisure battery, the bigger its physical size. The two most common leisure battery capacities are 85Ah and 110Ah. However, Euro Car Parts also sells examples with capacities of 75Ah, 95Ah, 100Ah and 115Ah. Some leisure vehicles use marine batteries. These are a form of leisure battery popular for use on boats and yachts. A marine battery makes use of a non-spill electrolyte in the form of a gel, while its casing is completely sealed. This avoids acid spillages in the event that the vehicle capsizes.