The two sides, the anode and the cathode contain opposite charges. The difference between the charges determines the potential of the battery. The potential can be described as stored energy, called electric potential energy. When the anode and cathode are connected by a circuit, the difference between the charges diminishes, which means this stored energy is being lost somehow. Different loads can harness this energy and convert it to another. Electric motors use magnetic fields induced by the electric current, which means that the electric potential energy is being converted into magnetic potential energy, which is immediately converted into kinetic energy, while incandescent light bulbs use electrical resistance of a filament to convert the electric potential, into a combination of infrared and visible light energy.
Chemical energy to electrical energy.
A battery stores chemical energy.
No. There are, indeed, ways to convert mechanical energy into electrical energy, but a battery is not usually designed to do this. You can convert mechanical energy to electrical energy by another device, but the battery itself has to be charged by electricity.
Chemical energy.
In a battery, the energy is stored as chemical energy, if that's what you mean. The exact details depend on the type of battery.
A battery
Battery
Wet cell battery and a motor.
A cell in a rechargeable battery does that when it's being recharged.
A rechargeable battery.
Think about a battery-powered motor. (Granted, the energy is originally chemical potential, but it is transferred to electrical potential when it comes out of the battery.)
mechanical generatornuclear reactorchemical battery