Lithiation Method for High-Energy, Long-Life Lithium-Ion Battery (L3B)

NREL is developing a low-cost method to overcome energy density and lifetime barriers faced by electric-drive vehicle batteries. Advanced anodes such as silicon are needed to enhance today's Li-ion cell energy densities and enable low cost, >200 mile range BEVs. But due to volume change during anode charge/discharge, these advanced cells presently lose more than 20% of their capacity on their first cycle. On subsequent cycles, the cells continue to degrade rapidly and only last 100-500 cycles. In comparison, the DOE BEV goal is 1000 cycles lifetime. This project goal is to enhance today's Li-ion cell energy density by 20% or more and lifetime by 50% or more by replenishing lost lithium. In addition to extending lifetime, the technology will pre-lithiate Li-starved systems to boost their initial capacity, addressing a present roadblock hindering commercialization of high-energy anode materials such as silicon. To date, NREL has more than doubled the lifetime of Si based cells supplied by Argonne National Lab's CAMP facility. The proposed device has been demonstrated in both pouch and cylindrical cells. The final design will occupy less than 5% of cell volume.