TY - JOUR
T1 - Enhanced Durability of Ca Metal Battery with Dual Salt
T2 - Synergistic Effect on Solid Electrolyte Interphase and Solvation Structure for Improved Electrodeposition
AU - Kisu, Kazuaki
AU - Dorai, Arunkumar
AU - Hatakeyama-Sato, Kan
AU - Takano, Tomoya
AU - Takagi, Shigeyuki
AU - Oyaizu, Kenichi
AU - Orimo, Shin Ichi
N1 - Publisher Copyright:
© 2024 American Chemical Society.
PY - 2025/1/8
Y1 - 2025/1/8
N2 - The use of Ca metal in battery technology is a promising approach owing to its high energy density and sustainability. However, the increased battery resistance during extended cycling significantly narrows its application range. This study aimed to improve the long-term stability of Ca deposition by employing a dual-salt strategy based on calcium monocarborane, Ca(CB11H12)2, which demonstrated favorable Ca deposition characteristics as a single-salt electrolyte. The addition of LiBr to Ca(CB11H12)2 resulted in a low battery resistance even after 200 h of cycling in contrast to the single-salt electrolyte whose resistance gradually increased. The dual-salt effect was examined by investigating solvation structures and electrolyte decomposition products. The introduction of Li cations into Ca(CB11H12)2 significantly altered the solid electrolyte interphase composition, effectively mitigating the increase in resistance during cycling. Furthermore, the inclusion of LiBr salt induced substantial changes in the solvation structures, reducing the number of solvent molecules surrounding Ca2+ ions. This transformation was accompanied by a noticeable decrease in the amount of CaCO3 among the electrolyte decomposition products and simultaneous increase in the polymer-based solid electrolyte interphase. The application of the dual-salt electrolyte comprising Ca(CB11H12)2 and LiBr demonstrated robust cycling stability over extended periods in two-electrode cells utilizing Ca metal anodes and anthraquinone-based organic cathodes. The capacity retention remained at 75% after 200 cycles, indicating the highest performance observed among the previously reported batteries containing Ca metal anodes and organic cathodes in two-electrode cell systems. This study highlights the efficacy of the dual-salt approach based on the stability of Ca(CB11H12)2 and its exceptional ability to enhance the long-term stability of Ca metal deposition, thereby significantly improving the practical application prospects of Ca-based batteries.
AB - The use of Ca metal in battery technology is a promising approach owing to its high energy density and sustainability. However, the increased battery resistance during extended cycling significantly narrows its application range. This study aimed to improve the long-term stability of Ca deposition by employing a dual-salt strategy based on calcium monocarborane, Ca(CB11H12)2, which demonstrated favorable Ca deposition characteristics as a single-salt electrolyte. The addition of LiBr to Ca(CB11H12)2 resulted in a low battery resistance even after 200 h of cycling in contrast to the single-salt electrolyte whose resistance gradually increased. The dual-salt effect was examined by investigating solvation structures and electrolyte decomposition products. The introduction of Li cations into Ca(CB11H12)2 significantly altered the solid electrolyte interphase composition, effectively mitigating the increase in resistance during cycling. Furthermore, the inclusion of LiBr salt induced substantial changes in the solvation structures, reducing the number of solvent molecules surrounding Ca2+ ions. This transformation was accompanied by a noticeable decrease in the amount of CaCO3 among the electrolyte decomposition products and simultaneous increase in the polymer-based solid electrolyte interphase. The application of the dual-salt electrolyte comprising Ca(CB11H12)2 and LiBr demonstrated robust cycling stability over extended periods in two-electrode cells utilizing Ca metal anodes and anthraquinone-based organic cathodes. The capacity retention remained at 75% after 200 cycles, indicating the highest performance observed among the previously reported batteries containing Ca metal anodes and organic cathodes in two-electrode cell systems. This study highlights the efficacy of the dual-salt approach based on the stability of Ca(CB11H12)2 and its exceptional ability to enhance the long-term stability of Ca metal deposition, thereby significantly improving the practical application prospects of Ca-based batteries.
KW - Ca metal batteries
KW - Ca(CBH)
KW - LiBr
KW - SEI
KW - dual salt electrolytes
KW - electrodeposition
KW - quinone electrode
UR - https://www.scopus.com/pages/publications/85212556892
UR - https://www.scopus.com/inward/citedby.url?scp=85212556892&partnerID=8YFLogxK
U2 - 10.1021/acsami.4c18599
DO - 10.1021/acsami.4c18599
M3 - Article
C2 - 39679897
AN - SCOPUS:85212556892
SN - 1944-8244
VL - 17
SP - 1322
EP - 1331
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 1
ER -