Layered lithium nickel oxide (LiNiO₂) is a promising cathode for high-energy lithium batteries, yet its conventional high-temperature solid-state (HS) synthesis inevitably involves an “ordered layered → disordered rocksalt → ordered layered” phase transformation, leading to structural defects and limited electrochemical performance. Here, we report a low-temperature reaction–high-temperature crystallization (LR–HC) strategy that decouples lithiation from crystallization, enabling topotactic conversion of Ni(OH)₂ into highly ordered LiNiO₂ while bypassing the detrimental rocksalt intermediate. The LR–HC, product crystallized at 700 °C for only 1 h, exhibits an exceptionally low rocksalt phase content on the surface and delivers an initial discharge capacity exceeding 220 mAh·g⁻¹ with an initial Coulombic efficiency above 90%. Remarkably, it retains 72.48% of its capacity after 200 cycles at 0.5 C, far outperforming the HS counterpart (53.10%). Operando X-ray diffraction (XRD) during cycling further demonstrates that the enhanced stability originates from a reduced c-axis contraction (4.19% vs. 6.43%) and a more reversible H2–H3 phase transition. The LR–HC strategy also proves versatile for synthesizing other high-nickel layered oxides (e.g., Ni₉₅Co₅ and Ni₉₅Mn₅), offering mechanistic insights into defect suppression and structural ordering for advanced cathode materials.

Lithium-ion batteries (LIBs) are pivotal in modern energy storage systems, yet their safety and longevity are critically threatened by several abuses. The over-discharge is overlooked in extreme operational conditions. Over-discharge in LIBs poses significant threats to performance and safety, inducing irreversible structural and electrochemical degradation. Key mechanisms include solid electrolyte interphase (SEI) layer breakdown, copper dissolution, and dendrite-induced internal short circuits, which accelerate capacity fade and thermal runaway risks. This review systematically analyzes these degradation pathways and evaluates mitigation strategies, such as voltage cutoff circuits, advanced battery management systems (BMS), and innovative protection strategies at the material level, like prelithiation and artificial SEI layers. The work also identifies gaps in current research, advocating for improved predictive models and industrial-scale solutions to address over-discharge challenges in next-generation energy storage systems.

Lithium metal batteries hold great promise for high performance energy storage due to their high theoretical energy density. However, practical implementation is hindered by interfacial side reactions and dendrite growth at the Li metal anode, particularly in carbonate-based electrolytes. Hereby, we introduce a novel multifunctional group additive strategy using 2-fluorobenzenesulfonamide (2-FBSA) to address these challenges. The 2-FBSA additive plays a crucial role in modulating the solvation structure of the electrolyte, facilitating Li⁺ transport kinetics by lowering the desolvation energy barrier. Additionally, the preferential decomposition of 2-FBSA at the anode interface leads to the formation of a robust solid electrolyte interphase (SEI) enriched with inorganic Li salts, including LiF, Li₃N, and ROSO₂Li. This SEI layer effectively suppresses Li dendrite growth and mitigates parasitic side reactions, resulting in significantly improved cycling stability and rate performance of Li||Li symmetric cells and Li||LiFePO₄ full cells. The Li||Li symmetric cell achieves a remarkable lifespan exceeding 2400 h at 0.5 mA·cm⁻²/1 mAh·cm⁻², while the Li||LiFePO₄ full cell demonstrates a capacity retention of 72% after 400 cycles at 1 C. This study highlights the potential of multifunctional group molecular additive 2-FBSA in interfacial optimization and provides new insights into additive design principles for high performance battery systems.

During the last decade, the rapid development of lithium-ion battery (LIB) energy storage systems has provided significant support for the efficient operation of renewable energy stations. In the coming years, the service life demand of energy storage systems will be further increased to 30 years from the current 20 years on the basis of the equivalent service life of renewable energy stations. However, the life of the present LIB is far from meeting such high demand. Therefore, research on the next-generation LIB with ultra-long service life is imminent. Prelithiation technology has been widely studied as an important means to compensate for the initial coulombic efficiency loss and improve the service life of LIBs. This review systematically summarized the different prelithiation methods from anode and cathode electrodes. Moreover, the large-scale industrialization challenge and the possibility of the existing prelithiation technology are analyzed, based on three key parameters: industry compatibility, prelithiation efficiency, and energy density. Finally, the future trends of improvement in LIB performance by other overlithiated cathode materials are presented, which gives a reference for subsequent research.

Ionic selectivity is of significant importance in both fundamental science and practical applications. For instance, an ion-selective material allows the passage of a particular kind of ions while blocking the others, which could be used for purification of materials. Herein, the Li-ion-selectivity of a garnet-type solid electrolyte is discussed by comparing the difference of activation energy between different ions migrating in solids. The high ion-selectivity is confirmed by harvesting high-purity metallic lithium (99.98 wt%) from low-lithium-purity sources (80 wt%) at a moderate temperature (190 ℃). This gives it huge potential in separating lithium with impurities especially alkali and alkali-earth elements. The cost of metallic lithium production is only 25% of the international lithium price. The proposed electrochemical metallic lithium separating method is advantageous compared with the traditional process in terms of efficiency, safety, and cost.

The lithium dendrite and parasitic reactions are two major challenges for lithium (Li) metal anode—the most promising anode materials for high-energy-density batteries. In this work, both the dendrite and parasitic reactions that occurred between the liquid electrolyte and Li-metal anode could be largely inhibited by regulating the Li⁺-solvation structure. The saturated Li⁺-solvation species exist in commonly used LiPF₆ liquid electrolyte that needs extra energy to desolvation during Li-electrodeposition. Partial solvation induced high-energy state Li-ions would be more energy favorable during the electron-reduction process, dominating the competition with solvent reduction reactions. The Li-symmetric cells that are cycling at higher temperatures show better performance; the cycled lithium metal anode with metallic lustre and the dendrite-free surface is observed. Theoretical calculation and experimental measurements reveal the existence of high-energy state Li⁺-solvates species, and their concentration increases with temperature. This study provides insight into the Li⁺-solvation structure and its electrodeposition characteristics.