LiFSI Lithium Bis(fluorosulfonyl)imide Salt offers cycle life, plus high and low operating temperature range stability compared to LiPF6 Lithium Hexaflurophosphate Salt. LiFSI salt has poorer long-term stability than LiPF6 at voltages above 3.9V. LiFSI has shown the ability to outperform LiPF6 salt in terms of total energy delivered over battery lifetime and therefore could potentially offer cost savings for energy storage applications where extremely long cycle life is important. The lower voltage stability of LiFSI means the cells have lower energy density compared to LiPF6 containing cells.
Novonix has done extensive research on the long-term performance of LiFSI salt in lithium-ion batteries. Key factors that affect performance such as operating temperatures, upper cut-off voltage, solvent selection for the electrolyte, salt concentration, etc. have been evaluated in relation to energy storage and other applications. Novonix used their UHPC cell testing equipment in order to optimize the LiFSI salt containing cell design to maximize lifetime energy delivery.
Charge Efficiency
Refer this to columbic efficiency.
