Designing weakly and strongly solvating polymer electrolytes: Systematically boosting high‐voltage lithium metal batteries
Tianyi Wang,
Yimeng Zhang,
Xueyan Huang,
Peifeng Su,
Min Xiao,
Shuanjin Wang,
Sheng Huang,
Dongmei Han,
Yuezhong Meng
Affiliations
Tianyi Wang
The Key Laboratory of Low‐carbon Chemistry & Energy Conservation of Guangdong Province State Key Laboratory of Optoelectronic Materials and Technologies School of Materials Science and Engineering Sun Yat‐sen University Guangzhou China
Yimeng Zhang
The Key Laboratory of Low‐carbon Chemistry & Energy Conservation of Guangdong Province State Key Laboratory of Optoelectronic Materials and Technologies School of Materials Science and Engineering Sun Yat‐sen University Guangzhou China
Xueyan Huang
Department of Chemical Engineering Tsinghua University Beijing China
Peifeng Su
The Key Laboratory of Low‐carbon Chemistry & Energy Conservation of Guangdong Province State Key Laboratory of Optoelectronic Materials and Technologies School of Materials Science and Engineering Sun Yat‐sen University Guangzhou China
Min Xiao
The Key Laboratory of Low‐carbon Chemistry & Energy Conservation of Guangdong Province State Key Laboratory of Optoelectronic Materials and Technologies School of Materials Science and Engineering Sun Yat‐sen University Guangzhou China
Shuanjin Wang
The Key Laboratory of Low‐carbon Chemistry & Energy Conservation of Guangdong Province State Key Laboratory of Optoelectronic Materials and Technologies School of Materials Science and Engineering Sun Yat‐sen University Guangzhou China
Sheng Huang
The Key Laboratory of Low‐carbon Chemistry & Energy Conservation of Guangdong Province State Key Laboratory of Optoelectronic Materials and Technologies School of Materials Science and Engineering Sun Yat‐sen University Guangzhou China
Dongmei Han
The Key Laboratory of Low‐carbon Chemistry & Energy Conservation of Guangdong Province State Key Laboratory of Optoelectronic Materials and Technologies School of Materials Science and Engineering Sun Yat‐sen University Guangzhou China
Yuezhong Meng
The Key Laboratory of Low‐carbon Chemistry & Energy Conservation of Guangdong Province State Key Laboratory of Optoelectronic Materials and Technologies School of Materials Science and Engineering Sun Yat‐sen University Guangzhou China
Abstract Practical high‐voltage lithium metal batteries hold promise for high energy density applications, but face stability challenges in electrolytes for both 4 V‐class cathodes and lithium anode. To address this, we delve into the positive impacts of two crucial moieties in electrolyte chemistry: fluorine atom (‐F) and cyano group (‐CN) on the electrochemical performance of polyether electrolytes and lithium metal batteries. Cyano‐bearing polyether electrolytes possess strong solvation, accelerating Li+ desolvation with minimal SEI impact. Fluorinated polyether electrolytes possess weak solvation, and stabilize the lithium anode via preferential decomposition of F‐segment, exhibiting nearly 6000‐h stable cycling of lithium symmetric cell. Furthermore, the electron‐withdrawing properties of ‐F and ‐CN groups significantly bolster the high‐voltage tolerance of copolymer electrolyte, extending its operational range up to 5 V. This advancement enables the development of 4 V‐class lithium metal batteries compatible with various cathodes, including 4.45 V LiCoO2, 4.5 V LiNi0.8Co0.1Mn0.1O2, and 4.2 V LiNi0.5Co0.2Mn0.3O2. These findings provide insights into design principles centered around polymer components for high‐performance polymer electrolytes.
