Battery storage refers to a technology that stores energy in a battery for later use. This type of storage is commonly used with renewable energy sources such as solar and wind power, where excess energy can be stored during periods of high production and then released back into the grid when demand is high or when production from renewable sources is low. Battery storage allows for more efficient use of renewable energy resources by providing a reliable source of electricity that can be used at any time, regardless of weather conditions or time of day.