TY - JOUR
T1 - Molecular Design of a Highly Stable Single-Ion Conducting Polymer Gel Electrolyte
AU - Liu, Kewei
AU - Jiang, Sisi
AU - Dzwiniel, Trevor L.
AU - Kim, Hong Keun
AU - Yu, Zhou
AU - Dietz Rago, Nancy L.
AU - Kim, Jae Jin
AU - Fister, Timothy T.
AU - Yang, Jianzhong
AU - Liu, Qian
AU - Gilbert, James
AU - Cheng, Lei
AU - Srinivasan, Venkat
AU - Zhang, Zhengcheng
AU - Liao, Chen
N1 - Publisher Copyright:
© 2020 American Chemical Society.
PY - 2020/7/1
Y1 - 2020/7/1
N2 - Single-ion conducting (SIC) polymer electrolytes with a high Li transference number (tLi+) have shown the capability to enable enhanced battery performance and safety by avoiding liquid-electrolyte leakage and suppressing Li dendrite formation. However, issues of insufficient ionic conductivity, low electrochemical stability, and poor polymer/electrode interfacial contact have greatly hindered their commercial use. Here, a Li-containing boron-centered fluorinated SIC polymer gel electrolyte (LiBFSIE) was rationally designed to achieve a high tLi+ and high electrochemical stability. Owing to the low dissociation energy of the boron-centered anion and Li+, the as-prepared LiBFSIE exhibited an ionic conductivity of 2 × 10-4 S/cm at 35 °C, which is exclusively contributed by Li ions owing to a high tLi+ of 0.93. Both simulation and experimental approaches were applied to investigate the ion diffusion and concentration gradient in the LiBFSIE and non-cross-linked dual-ion systems. Typical rectangular Li stripping/plating voltage profiles demonstrated the uniform Li deposition assisted by LiBFSIE. The interfacial contact and electrolyte infiltration were further optimized with an in situ UV-vis-initiated polymerization method together with the electrode materials. By virtue of the high electrochemical stability of LiBFSIE, the cells achieved a promising average Coulombic efficiency of 99.95% over 200 cycles, which is higher than that of liquid-electrolyte-based cells. No obvious capacity fading was observed, indicating the long-term stability of LiBFSIE for lithium metal batteries.
AB - Single-ion conducting (SIC) polymer electrolytes with a high Li transference number (tLi+) have shown the capability to enable enhanced battery performance and safety by avoiding liquid-electrolyte leakage and suppressing Li dendrite formation. However, issues of insufficient ionic conductivity, low electrochemical stability, and poor polymer/electrode interfacial contact have greatly hindered their commercial use. Here, a Li-containing boron-centered fluorinated SIC polymer gel electrolyte (LiBFSIE) was rationally designed to achieve a high tLi+ and high electrochemical stability. Owing to the low dissociation energy of the boron-centered anion and Li+, the as-prepared LiBFSIE exhibited an ionic conductivity of 2 × 10-4 S/cm at 35 °C, which is exclusively contributed by Li ions owing to a high tLi+ of 0.93. Both simulation and experimental approaches were applied to investigate the ion diffusion and concentration gradient in the LiBFSIE and non-cross-linked dual-ion systems. Typical rectangular Li stripping/plating voltage profiles demonstrated the uniform Li deposition assisted by LiBFSIE. The interfacial contact and electrolyte infiltration were further optimized with an in situ UV-vis-initiated polymerization method together with the electrode materials. By virtue of the high electrochemical stability of LiBFSIE, the cells achieved a promising average Coulombic efficiency of 99.95% over 200 cycles, which is higher than that of liquid-electrolyte-based cells. No obvious capacity fading was observed, indicating the long-term stability of LiBFSIE for lithium metal batteries.
KW - high transference number
KW - in situ syntheses
KW - lithium-ion batteries
KW - polymer
KW - single-ion electrolyte
UR - http://www.scopus.com/inward/record.url?scp=85087613190&partnerID=8YFLogxK
U2 - 10.1021/acsami.0c03363
DO - 10.1021/acsami.0c03363
M3 - Article
C2 - 32412737
AN - SCOPUS:85087613190
SN - 1944-8244
VL - 12
SP - 29162
EP - 29172
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 26
ER -