Publisher Summary This chapter discusses different types of lead-acid secondary batteries, such as stationary type or standby power batteries, traction power type, automotive batteries, and electric vehicle batteries. The choice of a standby system lies between batteries, usually lead-acid or nickel-cadmium, and generators, or a combination of the two. Large battery installations which are called upon only occasionally to supply power, usually in emergency or auxiliary power supply circumstances, are referred to as stationary or standby batteries. For many applications, the battery's ability to provide the power required instantly makes it more suitable. Partially recombining sealed lead-acid batteries are used in either cyclic or float service in a wide range of applications. The batteries feature lead-calcium alloy grids for achieving long and reliable service and also a suspended electrolyte system. These batteries are available in capacities between 5 and 50 A h.