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In this paper, we design a binder GG-CA-GLY (abbreviation: GGC) for silicon negative electrode by guar gum as the backbone chain with self-healing function, combing and straightening the guar molecular chain of guar gum through the plasticizing effect of glycerol. The condensation reactions between the exposed hydroxyl sites of guar gum and the carboxyl groups of citric acid create a stronger hydrogen bond, so as to achieve the effect of self-healing and cope with the serious volume expansion effect of silicone-based materials. [Display omitted] • A easy polycondensation reaction is used to create a mechanically strong self-healing polymer (GGC). • GGC adhesives have excellent mechanical properties and facilitate rapid self-healing. • GGC@Si electrodes were prepared with excellent rate capability and higher cycling stability. • GGC adhesives have the ability to repair cracks and other damage on prepared silicon anodes, returning them to their original state. Silicon is a promising anode material for lithium-ion batteries with its superior capacity. However, the volume change of the silicon anode seriously affects the electrode integrity and cycle stability. The waterborne guar gum (GG) binder has been regarded as one of the most promising binders for Si anodes. Here, a unique steric molecular combing approach based on guar gum, glycerol, and citric acid is proposed to develop a self-healing binder GGC, which would boost the structural stability of electrode materials. The GGC binder is mainly designed to weaken van der Waals' forces between polymers through the plasticizing effect of glycerol, combing and straightening the guar molecular chain of GG, and exposing the guar hydroxyl sites of GG and the carboxyl groups of citric acid. The condensation reaction between the hydroxyl sites of GG and the carboxyl groups of citric acid forms stronger hydrogen bonds, which can help achieve self-healing effect to cope with the severe volume expansion effect of silicone-based materials. Silicon electrode lithium-ion batteries prepared with GGC binders exhibit outstanding electrochemical performance, with a discharge capacity of up to 1579 mAh/g for 1200 cycles at 1 A/g, providing a high capacity retention rate of 96%. This paper demostrates the great potential of GGC binders in realizing electrochemical performance enhancement of silicon anode. [ABSTRACT FROM AUTHOR]

An in-situ integrated electrode/self-healable polymer electrolyte for ultra-long cycling life in all-solid-state Si-based lithium batteries, driven by the incorporation of multiple dynamic bonds. [Display omitted] • Integration of Si anode/self-healing polymer electrolyte by in situ polymerization. • The Li+ environment was studied by experimental and theoretical calculation. • The electrolyte has high ionic conductivity and wide electrochemical window. • The Si-SHDSE|SHDSE|LCO-SHDSE pouch cells prototype with ultra-long cycling life. For all-solid-state lithium-ion batteries (ASSLIBs), silicon (Si) stands out as an appealing anodes material due to its high energy density and improved safety compared to lithium metal. However, the substantial volume changes during cycling result in poor solid-state physical contact and electrolyte–electrode interface issues, leading to unsatisfactory electrochemical performance. In this study, we employed in-situ polymerization to construct an integrated Si anodes/self-healing polymer electrolyte for ASSLIBs. The polymer chain reorganization stems from numerous dynamic bonds in the constructed self-healing dynamic supermolecular elastomer electrolyte (SHDSE) molecular structure. Notably, SHDSE also serves as a Si anodes binder with enhanced adhesive capability. As a result, the well-structured Li|SHDSE|Si-SHDSE cell generates subtle electrolyte–electrode interface contacts at the molecular level, which can offer a continuous and stable Li+ transport pathway, reduce Si particle displacement, and mitigate electrode volume expansion. This further enhances cyclic stability (>500 cycles with 68.1 % capacity retention and >99.8 % Coulombic efficiency). More practically, the 2.0 Ah wave-shaped Si||LiCoO 2 soft-pack battery with in-situ cured SHDSE exhibits strongly stabilized electrochemical performance (1.68 Ah after 700 cycles, 86.2 % capacity retention) in spite of a high operating temperatures up to 100 °C and in various bending tests. This represents a groundbreaking report in flexible solid-state soft-pack batteries containing Si anodes. [ABSTRACT FROM AUTHOR]

[Display omitted] • A weakly solvating electrolyte constructs a highly robust and stable F-rich inorganic–organic bilayer solid–electrolyte interphase on Si anodes. • F-rich inorganic–organic bilayer SEI layer boosts anode structure and electrolyte stability. • Si anodes with a weakly solvating electrolyte exhibit ∼99.9 % ultra-high Coulombic efficiency and ultra-high areal capacity (∼8.1 mAh cm−2). • A pouch cell achieves 84.3 % capacity retention after 1000 cycles, and could work normally at temperatures ranging from −30 °C to 100 °C. Silicon (Si) anodes has emerged as an ideal anode for the next generation of lithium-ion batteries owing to its high specific capacity. Nevertheless, Si particles undergo large volume expansion during cycling, inducing the continuous fragmentation/re-formation of the solid-electrolyte interphase (SEI) layer, which leads to rapid capacity decay and low Coulombic efficiency in EC-based carbonate electrolytes. Herein, a weakly solvating electrolyte with boric acid tris(hexafluoroisopropyl) ester (BTHE), 2,2,2-trifluoroethyl methyl carbonate (FDEC), and fluoroethylene carbonate (FEC) is developed to build a stable SEI. BTHE is introduced as a functional additive, which is induce anion and fluorinated solvent to form a gradient rigid–soft coupling SEI layer. In contrast to other anion-derived interfaces, weakly solvating electrolyte has been proven to construct a highly robust and stable –CF 3 -rich-organic outer layer and LiF-rich inner layer SEI on the Si anodes, resulting in approximately 99.9 % ultra-high Coulombic efficiency and ultra-high areal capacity (∼8.1 mAh cm−2). Beyond proof of concept, a 2.68 Ah Si||LiNi 0.8 Mn 0.1 Co 0.1 O 2 pouch cell has an impressive 84.3 % capacity retention after 1000 cycles and could work normally at temperatures ranging from −30 °C to 100 °C based on this electrolyte, representing a pioneering report in pouch cells incorporating Si anodes. [ABSTRACT FROM AUTHOR]