The United Kingdom electric bus battery pack market refers to a group of businesses in the automotive and transportation industry that design, manufacture, integrate, and supply battery energy storage systems for electric buses. These battery energy storage systems are usually based on lithium-ion chemistries, such as lithium iron phosphate or nickel manganese cobalt. Electric bus battery packs are the main source of electric power for urban and inter-city transit fleets, thereby providing zero-emission transportation while decreasing dependence on diesel powered buses.