A dense transparent polymeric single ion conductor for lithium ion batteries with remarkable long-term stability

作者：Pan, Qiyun; Chen, Yazhou; Zhang, Yunfeng; Zeng, Danli; Sun, Yubao^*; Cheng, Hansong^*

来源：Journal of Power Sources, 2016, 336: 75-82.

DOI：10.1016/j.jpowsour.2016.10.033

• Single ion conducting polymer electrolyte
• Transference number
• Side chain grafting
• Ion exchange capacity

We report an outstanding electrochemical performance of a gel type lithium ion battery with long cycle life enabled by a dense transparent polymeric single ion conductor. The polymer electrolyte was synthesized by a side chain grafting method with 4-amino-4'-trifiuoromethyl bis(benzene sulfonyl)imide grafted on side chains of poly(ethylene-alt-maleic anhydride) with a grafting ratio of 50%. Blending lithiated iononmers with poly(vinylidene fluoride-co-hexafluoropropylene) via a solution cast method results in a dense transparent film. The fabricated blend polymer electrolyte film has an ionic conductivity of 0.104 mS cm(-1) at room temperature, a tensile strength of 15.5 MPa and percent elongation at break of 5%. A gel type single ion conductive polymeric lithium ion battery was assembled using the blend film as the separator as well as the electrolyte, LiFePO4/C mixed with ionomers as the cathode and a lithium foil as the anode. The battery delivers a reversible discharge capacity of 100 mAh g(-1) at 1 C under room temperature for 1000 cycles without obvious decay. The stable cyclic imide and comb-like structure of the polymer is largely responsible for the excellent battery performance. The side chain grafted single ion conducting polymer electrolyte is well suited for large-scale production.

• 出版日期2016-12-30
• 单位中国地质大学（北京）