Batteries can be rated in Amp-Hours, how many hours it can deliver a 1 amp current.
Example: 250 Amp-Hr battery can deliver 1 amp for 250 hours, 10 amps for 25 hours, etc.
Also rated in W-hr/kg, an energy density or power density, W/kg
A battery is an electrical storage device that comes in many shapes, sizes, weights and chemical compounds. They all have one thing in common, they store electrical current.
The most common type of battery used in solar electric systems is the deep cycle lead acid battery.
Deep cycle batteries are designed to be repeatedly cycled (charged and discharged).
An automobile starting battery is different. It is designed to provide a powerful short burst of energy to start the engine. As soon as the engine is started the alternator recharges the battery. If an automotive battery was used in a solar application a very short life should be expected.
Nickel metal-hydride (NiMH) rechargeable battery technology is being developed. Used now in portable computers. Large Scale is being tested and developed.
Batteries that operate at higher temperatures exist (300C). Applicable to Power Plants, maybe not home use
PV Cells put out DC voltages. This signal must be converted to a.c. to run motors and appliances. Also if you want to sell energy back to the grid. Well, its complicated and we are running out of time. This is possible. Checkout the site
Inverter Products ONE EXAMPLE....
Hydrogen Storage:
Facts about Hydrogen and Links to hydrogen information
Flow Batteries Levels load requirment at generatinmg stations.
Flywheels; Energy storage using Mechanical Kinetic Energy
Pumped Hydro, Compressed Air, Capacitors: other means of storing energy