Application of amide solvents in electrolytes significantly improves specific energy of Li/CFx primary batteries

Lithium/Carbon Fluoride (Li/CF x ) primary batteries are widely regarded as one of the most promising electrochemical energy supply technologies in the military and medical fields due to their high energy density, low self-discharge rate, and good safety performance. However, Li/CF x batteries suffer from poor power density and severe voltage hysteresis, and solutions are often considered in terms of both cathode and electrolyte. In this work, an N,N-dimethylacetamide (DMA)-based electrolyte was designed to enhance the discharge platform of Li/CF x . The results show that DMA has a high dielectric constant and can effectively improve the ionic conductivity of the electrolyte as well as increase the solubility of lithium salts in the electrolyte. The optimized electrolyte was 1 M lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) dissolved in DMA and PC (7:3 vol ratio). At 1C discharge rate, the specific capacity reached 726 mAh/g, the specific energy reached 1634 Wh/kg, and the voltage platform was raised to 2.32 V. The optimized electrolyte also demonstrates better discharge performance in pouch batteries.