High-energy Lithium-based battery technology is a crucial support for achieving the national "dual-carbon" goals. In the technology, silicon (Si)-based anodes are considered as one of the most promising choices for next-generation high-energy Li-ion batteries (LIBs) due to their ultra-high specific capacity, which is 10 times greater than that of graphite (i.e., silicon 4200 mA·h/g). When a "Si-majority" anode (mass fraction of silicon greater than 50% in the anode) works with a high-nickel LiNi_xMn_yCo_zO₂ (x+y+z=1, x≥0.6) cathode, the cell-level energy density can increase to over 400 Wh/kg. However, silicon usually experiences significant volume changes (i.e., over 300%) during lithiation and delithiation, leading to structural degradation, pulverization, unstable electrode-electrolyte interfaces, and gas generation, which pose substantial challenges to the cycling life of silicon-based anode batteries. Also, there is still a lack of clarifying key scientific issues such as interfacial evolution and failure mechanisms under practical conditions. Recent research on silicon-based anodes can be summarized as two main directions.1) Structure design and composites: Since nano-sized Si as an anode for LIBs was proposed, most of studies focus on the design of various nanostructured Si materials to improve their cycling stability, such as nanowires, hollow, porous, and core-shell Si anodes. However, nano-sized Si anodes suffer from a low initial Coulombic efficiency, a low packing density, and a high cost. To address these issues, Si-graphite composite materials are invented to buffer the volume expansion of Si via embedding those into graphite layers, thus improving the cycling stability and become a recent hot topic.2) Electrolyte engineering: For Si-majority or pure-Si anodes, neither structural design nor graphite confinement can fully alleviate the issues caused by volume expansion, such as the cracking of the solid electrolyte interphase (SEI) and pulverization. Another strategy based on electrolyte engineering is thus proposed to form stable SEI with high ionic conductivity and favorable mechanical properties on the Si surface. Carbonate-based electrolytes, known for their strong oxidation resistance, are highly compatible with high-voltage cathodes (>4 V vs. Li/Li⁺). For Si-based anodes, fluorinated ethylene carbonate (FEC) is considered as the most effective electrolyte component. However, FEC suffers from its poor thermal stability, leading to poor high-temperature cycling life and serious gassing at high temperatures. Ether-based electrolytes, featuring their strong reductive resistance, are extensively studied for Si-based anodes. For instance, some studies report that the rationally designed ether-based electrolytes can enable a high specific capacity of ~2400 mA·h/g with stable cycling for over 200 cycles. These findings demonstrate that the interface stability of Si-majority/pure-Si anodes can be improved through electrolyte design and optimization, thus enhancing their cycling life.From the perspective of actual battery operating conditions, a research on electrolytes still faces some challenges. For silicon anodes with FEC-based carbonate electrolytes, the cycling performance is less than ideal, particularly due to the poor high-temperature stability of FEC and the issues of gas generation, which remain difficult to resolve. Ether-based electrolytes can improve the cycling stability of silicon-based anodes, and exhibit a poor oxidation resistance. This poses challenges such as oxidative decomposition and high-temperature gas generation, especially when paired with high-voltage cathodes and operating in high-temperature environments. It is thus essential for the practical application of such electrolytes to overcome these issues. An analysis spanning from fundamental mechanisms to practical implementation identifies the key points for the design and development of electrolytes tailored for silicon-based anodes:Summary and prospectsThis review represents the research progress on Si-based anodes from material structure to electrolyte design, and highlights the need to clarify the degradation mechanisms of Si-based anodes, develop novel characterization methods, and design new molecular structures to improve interfacial stability. Some efforts in future research should be directed towards the following aspects, i.e., 1) further elucidating the degradation mechanisms of Si-based anodes from the chemomechanical viewpoint. The Si-based anodes work under cyclic stress and chemical corrosion, which are highly intertwined. This coupling effect is highly analogous to the "stress corrosion cracking" well known in metals. Clarifying and decoupling these two failure mechanisms can guide the design of both electrodes and electrolytes, 2) developing novel interdisciplinary characterization and research methods. These methods should employ both in-situ and ex-situ techniques in microscale to investigate crack propagation and structural evolution of electrodes and interfaces under various chemical environments, 3) evaluating novel electrolytes under realistic conditions. It is essential to assess the performance of batteries, including cycling and gas generation, under realistic conditions such as high-loading electrodes, lean electrolytes, large-format cells and extreme temperatures to analyze the battery degradation mechanisms, 4) electrolyte design for Si–C anodes must consider the compatibility of both Si and Graphite. Since the requirements for electrolytes differ between graphite and silicon, a design needs to balance the compatibility of different solvents and additives with the both materials, and 5) developing novel additives and solvent molecules. Designing new molecules to replace FEC and address the gassing issue at high temperatures is quite meaningful for practical applications. The design of these molecules should ensure superior oxidation resistance, compatibility with high-voltage cathodes, stability with trace amounts of water in the electrolyte, and good chemical stability at high temperatures.