Transport Phenomena in Low Temperature Lithium-Ion Battery Electrolytes

Lithium-ion batteries face low temperature performance issues, limiting the adoption of technologies ranging from electric vehicles to stationary grid storage. This problem is thought be exacerbated by slow transport within electrolyte, which in turn may influenced ion association, solvent viscosity, and cation transference number. How these factors collectively impact phenomena, however, remains poorly understood. Here we show using all-atom classical molecular dynamics (MD) simulations that dominant factor influencing LP57 (1 M LiPF 6 3:7 ethylene carbonate (EC)/ethyl methyl (EMC)) rather than aggregation or We find association decreases with decreasing temperature, while number positive roughly independent temperature. In an effort improve performance, introduce ? -butyrolactone (GBL) as a viscosity co-solvent explore two alternative formulations: 1 15:15:70 EC/GBL/EMC GBL/EMC. While GBL reduces solution its dielectric constant results increased pairing, yielding neither improved bulk ionic conductivity nor appreciably altered mechanisms. expect will enhance understanding inform development superior electrolytes.