AllCell Technologies has released a white paper comparing the economics of lithium-ion and lead acid batteries for stationary energy storage systems (ESS). Even though the initial purchase price of lead acid batteries is one-fifth the price of lithium-ion, when analyzed on a full life-cycle basis lithium-ion batteries are now cost-competitive in moderate climates and lower cost in hot climates. As solar photovoltaic costs continue to fall, the lightweight, long life cycle, and deep discharge capacity of lithium-ion battery systems will enable a growing range of mobile, portable, and off-grid products and applications to become economically feasible.