Lithium‐ion batteries (LIBs) with higher energy density are very necessary to meet the increasing demand for devices with better performance. With the commercial success of lithiated graphite, other graphite intercalation compounds (GICs) have also been intensively reported, not only for LIBs, but also for other metal (Na, K, Al) ion batteries. In this Progress Report, we briefly review the application of GICs as anodes and cathodes in metal (Li, Na, K, Al) ion batteries. After a brief introduction on the development history of GICs, the electrochemistry of cationic GICs and anionic GICs is summarized. We further briefly summarize the use of cationic GICs and anionic GICs in alkali ion batteries and the use of anionic GICs in aluminium‐ion batteries. Finally, we reach some conclusions on the drawbacks, major progress, emerging challenges, and some perspectives on the development of GICs for metal (Li, Na, K, Al) ion batteries. Further development of GICs for metal (Li, Na, K, Al) ion batteries is not only a strong supplement to the commercialized success of lithiated‐graphite for LIBs, but also an effective strategy to develop diverse high‐energy batteries for stationary energy storage in the future.

Alkali lignin, recovered from the pulping black liquor, was chemically modified by acetylating, and then used as a biomass resource to prepare uniform colloidal spheres via self-assembly. The self-assembled structure and colloid formation mechanism of the acetylated lignin (ACL) were investigated by DLS, SLS, TEM, AFM, XPS, FTIR, elemental analysis and contact angle measurements. Results show that ACL colloidal spheres are obtained from gradual hydrophobic aggregation of ACL molecules, induced by continuously adding water into the ACL–THF solution. ACL molecules start to form colloidal spheres at a critical water content of 44 vol% when the initial concentration of ACL in THF is 1.0 mg mL⁻¹, and the colloidization process is completed at a water content of 67 vol%. An excessive amount of water is added into the dispersions to “quench” the structures formed and then the ACL dispersion is treated by rotary evaporation for recycling THF and acquiring colloidal spheres. The ACL colloidal spheres have an <R_h> of 110 nm with a polydispersity (μ₂/Γ²) of 0.022. The average aggregated number (<N_agg>) in each colloidal sphere and the average density (<ρ>) are estimated to be 1.0 × 10⁵ and 0.187 g cm⁻³. Preparation of water-dispersive lignin nanoparticles opens up a green and valuable pathway for value-added utilization of lignin biomass recovered from pulping spent liquor, which is of great significance for both the utilization of renewable resources and environmental protection.

The electrochemical stability window of the electrolyte solution limits the energy content of non-aqueous lithium metal batteries. In particular, although electrolytes comprising fluorinated solvents show good oxidation stability against high-voltage positive electrode active materials such as LiNi_0.8Co_0.1Mn_0.1O₂ (NCM811), the ionic conductivity is adversely affected and, thus, the battery cycling performance at high current rates and low temperatures. To address these issues, here we report the design and synthesis of a monofluoride ether as an electrolyte solvent with Li-F and Li-O tridentate coordination chemistries. The monofluoro substituent (-CH₂F) in the solvent molecule, differently from the difluoro (-CHF₂) and trifluoro (-CF₃) counterparts, improves the electrolyte ionic conductivity without narrowing the oxidation stability. Indeed, the electrolyte solution with the monofluoride ether solvent demonstrates good compatibility with positive and negative electrodes in a wide range of temperatures (i.e., from −60 °C to +60 °C) and at high charge/discharge rates (e.g., at 17.5 mA cm⁻²). Using this electrolyte solution, we assemble and test a 320 mAh Li||NCM811 multi-layer pouch cell, which delivers a specific energy of 426 Wh kg⁻¹ (based on the weight of the entire cell) and capacity retention of 80% after 200 cycles at 0.8/8 mA cm⁻² charge/discharge rate and 30 °C.