 This research paper examines the effect of temperature on the performance of Li-ion batteries. It found that the rate of Li-plus transport decreased significantly when the temperature was reduced below minus 20 degrees Celsius. This was due to the slower diffusion of Li-plus through the solid electrolyte interface, SEI, layer. The authors then proposed a solution to this problem by using fluorinated electrolytes with a lower limo energy level and polar groups. These fluorinated electrolytes formed an inorganic-rich SEI layer that had better tolerance to changes in temperature and improved Li-plus transport.