High voltage stable solid-state lithium battery based on the nano-conductor imbedded flexible hybrid solid electrolyte with hyper-ion conductivity and thermal, mechanical, and adhesive stability

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2022-05, Vol.435, p.135092, Article 135092
• Main Authors: Hoang, Hai Anh, Kim, Dukjoon
• Format: Article
• Language: English
• Subjects: Conductive binders; Hybrid solid electrolytes; Lithium-ion conductivity; Solid-state lithium batteries
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2022.135092

In this study, a strategy for the systematic fabrication of high voltage stable solid-state lithium batteries by combining the multi-functional solid electrolyte with the surface protected cathode material is developed. The membranes fabricated from this material expresses good mechanical, thermal, electrochemical, and adhesive properties, which well-matched the requirements for solid electrolyte membranes and conductive binders of lithium secondary batteries. [Display omitted] •Multi- functional PVA-g-PCA-IL-HTpca for simple fabrication of solid-state Li battery.•High lithium-ion conductivity of PVA-g-PCA-IL-HTpca hybrid solid electrolyte.•Excellent adhesive strength of Li conductive PVA-g-PCA-IL-HTpca binder.•Excellent electrochemical performance at high voltage and high temperature. Hybrid solid electrolyte (HSE) is a potential candidate in lithium secondary battery to replace the traditional liquid electrolyte with the superiority of solid state. We propose an optimal design for the high voltage stable solid-state lithium battery system by combining the HSE composed of poly(vinyl alcohol)-g-pyrrole-2-carboxylic acid (PVA-g-PCA) and pyrrole-2-carboxylic acid modified hydrotalcite (HTpca) nano-conductor and the Al2O3 coated LiCoO2 active material. The flexible and non-flammable PVA-g-PCA-80IL-5HTpca HSE exhibits outstanding Li+ conductivity of 4.78 × 10−3 S cm−1 and Li+ transference number of 0.72 at room temperature in a wide electrochemical window up to 5.17 V vs Li+/Li, maintaining the long-term stability with Li metal over 500 cycles and low interfacial resistance of 42 Ω cm2 with cathode prepared by PVA-g-PCA-60IL-5HTpca. Utilized as a conductive binder, PVA-g-PCA-60IL-5HTpca HSE ensures the dense packing and uniform distribution of LiCoO2 particles and the excellent adhesion strength with the current collector (>24 MPa). Assembled with the Al2O3 coated LiCoO2 active material, the solid-state lithium batteries display the specific capacity of 188.7 mAh g−1 and the long-term cycling stability over 200 cycles at 4.5 V and 60 °C.