A novel dual-salts of LiTFSI and LiODFB in LiFePO4-based batteries for suppressing aluminum corrosion and improving cycling stability

• A novel dual-salts of LiTFSI and LiODFB has been used in LiFePO4-based batteries.
• LiTFSI–LiODFB-based electrolyte shows good anti-corrosion performance to Al foil.
• Li|LiFePO4 cells using LiTFSI–LiODFB-based electrolyte show good cycling stability and rate performance.
• Li|LiFePO4 cells using LiTFSI–LiODFB-based electrolyte has an appropriate conductivity.

The strong corrosion behavior at the Al current collector restricts the application range of lithium bis (trifluoromethanesulfonylimide) (LiTFSI), despite its high stability against water and thermal. SEM, LSV and Tafel curves proved that adding LiODFB into LiTFSI-based electrolytes could suppress aluminum corrosion caused by LiTFSI-based electrolytes. The cycling stability and rate capability of LiFePO4-based batteries using LiTFSI0.6–LiODFB0.4-based electrolytes is excellent as compared to LiFePO4-based batteries using LiPF6-based electrolytes.