Energy storage cabinet energy ring lead-acid battery

Lead–acid batteries have been used for energy storage in utility applications for many years but it has only been in recent years that the demand for battery energy storage has increased.

Currently, stationary energy-storage only accounts for a tiny fraction of the total sales of lead–acid batteries. Indeed the total installed capacity for stationary applications of lead–acid in 2010 (35 MW) was dwarfed by the installed capacity of sodium–sulfur batteries (315 MW), see Figure 13.13.

Electrochemical energy storage in batteries is attractive because it is compact, easy to deploy, economical and provides virtually instant response both to input from the battery and output from the network to the battery.

Improvements to lead battery technology have increased cycle life both in deep and shallow cycle applications. Li-ion and other battery types used for energy storage will be discussed to show that lead batteries are technically and economically effective. The sustainability of lead batteries is superior to other battery types.

Lead–acid batteries may be flooded or sealed valve-regulated (VRLA) types and the grids may be in the form of flat pasted plates or tubular plates. The various constructions have different technical performance and can be adapted to particular duty cycles. Batteries with tubular plates offer long deep cycle lives.

Lead–acid batteries typically have coulombic (Ah) efficiencies of around 85% and energy (Wh) efficiencies of around 70% over most of the SoC range, as determined by the details of design and the duty cycle to which they are exposed. The lower the charge and discharge rates, the higher is the efficiency.