Comparison of lead-acid and lithium ion batteries for stationary storage in off-grid energy systems

Different battery chemistries fit different applications, and certain battery types stand out as preferable for stationary storage in off-grid systems. Rechargeable batteries have widely varying efficiencies, charging characteristics, life cycles, and costs. This paper compares these aspects between the lead-acid and lithium ion battery, the two primary options for stationary energy storage. The various properties and characteristics are summarized specifically for the valve regulated lead-acid battery (VRLA) and lithium iron phosphate (LFP) lithium ion battery. The charging process, efficiency, and life cycle are discussed for each battery type. Through cost analysis specifically, lithium ion batteries are shown to be a cost-effective alternative to lead-acid batteries when the length of operational life - total number of charge/discharge cycles - is considered. Finally, applications for off-grid applications and specifically developing world microgrids are discussed.