Typically this used to be the case. Today most batteries are now encased in polypropylene which is considered to be a good insulator. Battery cases long ago used to be made of a rubber that had a high carbon content. If the battery was set on moist concrete an electrical current could be conducted through the case if the floor made an electrical ground. All batteries will eventually self discharge due to chemical changes, heat, cold and other outside issues. It is still recommended to fully charge the battery and place the battery on a platform that cannot absorb water or conduct temperature to prolong battery storage life.
No, they discharge. The alternator recharges the battery when the engine is running.
An electric car needs to be charged until the indicator on the charger says the batteries are charged. It will depend on the amperage of the batteries, the way the charging mechanism works, and the percentage of discharge of the batteries.
Static discharge, the tires insulate the car from the ground so when you step out you become the path to ground and zap.
Automotive batteries are not known for their "deep cycle" capabilities. If possible, don't allow them to EVER discharge completely.
NO, but like any Battery, if it is punctured and the contents leak out, it is possible.
Car batteries are rechargeable storage batteries. They are designed to be constantly recharged.
If you allow it to discharge, then it becomes useless, so you have to recharge it. Some batteries (e.g. for torches) don't have to be charged because their internal chemistry is such that they come already 'full'. But once they discharge then you have to throw them away.
Because it gives a ground point for static electricity to discharge to.
Yes, they will gradually discharge over time. If it is a rechargeable battery - such as a car battery - it can be recharged again, but the energy that was stored in it is lost.
car batteries
DC definitely, all car batteries - all batteries.
BJ'S sells Excide car batteries.