A battery energy storage system (BESS) or battery storage power station is a type of energy storage technology that uses a group of batteries to store electrical energy.
The most common type of battery used in energy storage systems is lithium-ion batteries. In fact, lithium-ion batteries make up 90% of the global grid battery storage market. A Lithium-ion battery is the type of battery that you are most likely to be familiar with. Lithium-ion batteries are used in cell phones and laptops.
Individual batteries form the core of the BESS system, storing electrical energy through electrochemical reactions. These batteries are typically made up of lithium-ion cells due to their high energy density and long lifespan. Cells are grouped together into modules to achieve the desired energy capacity and power output.
Battery energy storage systems store chemical energy and release it again to produce power. There are several important types of battery energy storage systems, some well established, some new. Common types include lead-acid batteries, found in motor vehicles, nickel cadmium and nickel hydride batteries, and sodium sulfur and lithium-ion batteries.
The most natural users of Battery Energy Storage Systems are electricity companies with wind and solar power plants. In this case, the BESS are typically large: they are either built near major nodes in the transmission grid, or else they are installed directly at power generation plants.
BESS are one of the main energy storage system: sometimes they are also called electrochemical energy systems to distinguish them from others, such as gravitational energy systems (including pumped-storage hydroelectric power plants), mechanical energy systems (including compressed air or flywheel systems) and (Thermal Energy Storage, TES) systems