High Performance Solid Polymer Electrolytes for Rechargeable Batteries: A Self-Catalyzed Strategy toward Facile Synthesis.

Yanyan Cui,Qinglei Wang,Xinmiao Liang,Xiaochen Liu,Zhihong Liu,Weisheng He,Guanglei Cui,Zili Cui,Jingchao Chai,Jiwen Feng

doi:10.1002/advs.201700174

Abstract

It is urgent to seek high performance solid polymer electrolytes (SPEs) via a facile chemistry and simple process. The lithium salts are composed of complex anions that are stabilized by a Lewis acid agent. This Lewis acid can initiate the ring opening polymerization. Herein, a self‐catalyzed strategy toward facile synthesis of crosslinked poly(ethylene glycol) diglycidyl ether‐based solid polymer electrolyte (C‐PEGDE) is presented. It is manifested that the poly(ethylene glycol) diglycidyl ether‐based solid polymer electrolyte possesses a superior electrochemical stability window up to 4.5 V versus Li/Li+ and considerable ionic conductivity of 8.9 × 10−5 S cm−1 at ambient temperature. Moreover, the LiFePO4/C‐PEGDE/Li batteries deliver stable charge/discharge profiles and considerable rate capability. It is demonstrated that this self‐catalyzed strategy can be a very effective approach for high performance solid polymer electrolytes.

Highlights

It is urgent to seek high performance solid polymer electrolytes (SPEs) via a high safety and high energy solid state lithium batteries.[1]
The reaction could not be initiated by lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and lithium bis(oxalato)borate (LiBOB) at a temperature of 80 °C
We have prepared a crosslinked poly(ethylene glycol) diglycidyl ether-based electrolyte by a self-catalyzed strategy and in situ technology via a facile cationic polymerization initiated by lithium salts

Summary

Results and Discussion

Some polymer electrolyte was incorporated into the porous cathodes originated from the in situ polymerization process when compared with that of the pristine LiFePO4 cathode (Figure 7b). These results manifested that close contact between the SPE and cathode interface would be greatly beneficial for improving the electrolyte/electrode interfacial contacts and mitigating the interfacial impedance. It was demonstrated that the initial capacity fading within the first 20 cycles was attributed to the increasing electrochemical reaction resistance (Re + Rct)

Conclusion

Experimental Section

Conflict of Interest