A leisure battery is used in a caravan or boat. It differs from a car battery in that it is designed to be slowly discharged & will not deteriorate so quickly if left partly charged. A car battery can be used as a leisure battery but as it is designed for a large fast discharge when starting car followed by a fast charge it will deteriorate much quicker when used as leisure battery.
You could of course use a leisure battery in a box in your tent & recharge it when you got home.
A leisure as sold by caravan shops is basically a reinforced car battery not a true deep cycle battery which is more expensive.
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