Lithium‐ion batteries (LIBs) are promising candidates within the context of the development of novel battery concepts with high energy densities. Batteries with high operating potentials or high voltage (HV) LIBs (>4.2 V vs Li⁺/Li) can provide high energy densities and are therefore attractive in high‐performance LIBs. However, a variety of challenges (including solid electrolyte interface (SEI), lithium plating, etc.) and related safety issues (such as gas formation or thermal runaway effects) must be solved for the practical, widespread application of HV‐LIBs. Most of these challenges arise in the region between the electrodes: the electrolyte region. This review provides an overview of recent development and progress on the electrolyte region, including liquid electrolytes, ionic liquids, gel polymer electrolytes, separators, and solid electrolytes for HV‐LIBs applications. A focus on improving the safety of these systems, with some perspectives on their relative cost and environmental impact, is given. Overall, the new information is encouraging for the development of HV‐LIBs, and this review serves as a guide for potential strategies to improve their safety, allowing the development of HV‐LIBs, including solid‐state batteries, to be accelerated to practical relevance.

Batteries are the backbones of the sustainable energy transition for stationary off-grid, portable electronic devices, and plug-in electric vehicle applications. Both lithium-ion batteries (LIBs) and sodium-ion batteries (NIBs), most commonly rely on carbon-based anode materials and are usually derived from non-renewable sources such as fossil deposits. Biomass-derived carbon materials are extensively researched as efficient and sustainable anode candidates for LIBs and NIBs. The main purpose of this perspective is to brief the use of biomass residues for the preparation of carbon anodes for LIBs and NIBs annexed to the biomass-derived carbon physicochemical structures and their aligned electrochemical properties. In addition, an outlook and some challenges faced in this promising area of research is presented. This review enlightens the readers with valuable insights and a reasonable understanding of issues and challenges faced in the preparation, physicochemical properties, and application of biomass-derived carbon materials as anode candidates for LIBs and NIBs.

Greener batteries are an emerging approach for sustainable environments and a promising technology for future batteries. In this review, we discuss the main issues to fully achieve the potential of batteries with greener approaches.

The global need for high-energy-density batteries has pushed for the development of high-performance battery materials such as cathodes and anodes to meet the huge energy demands in our modern society. Graphite (Gr) is the dominant anode material for lithium-ion batteries but possesses a lower theoretical capacity of 372 mAh g⁻¹, which hinders the fabrication of more powerful batteries. On the other hand, silicon (Si) possesses an extremely higher theoretical capacity than graphite (4200 mAh g⁻¹ in a composite of Li_4.4Si vs graphite: 372 mAh g⁻¹). Unfortunately, Si anode has issues with high volume changes (up to 400%) during cycling. Mixing/compositing silicon with carbon (Si/C) is set to be a realistic strategy to overcome issues related to the volume changes of Si and the low capacity of graphite. Instead, coupling both elements enables the combination of the two main materials’ properties, such as the high lithiation performance of Si and outstanding mechanical stability and conductivity of the carbon, which allows the battery to reach high storage capacity under elevated stability over longer cycles. In this review, Si/C materials anode materials synthesis methods, structural and morphological characteristics, and electrochemical performances are discussed as well as major challenge to overcome pulverization of Si during the charge/discharge process, and potential challenges of designing Si/C.

The advantages of cobalt-free, high specific capacity, high operating voltage, low cost, and environmental friendliness of spinel LiNi_0.5Mn_1.5O₄ (LNMO) material make it one of the most promising cathode materials for next-generation lithium-ion batteries. The disproportionation reaction of Mn³⁺ leads to Jahn–Teller distortion, which is the key issue in reducing the crystal structure stability and limiting the electrochemical stability of the material. In this work, single-crystal LNMO was synthesized successfully by the sol-gel method. The morphology and the Mn³⁺ content of the as-prepared LNMO were tuned by altering the synthesis temperature. The results demonstrated that the LNMO_110 material exhibited the most uniform particle distribution as well as the presence of the lowest concentration of Mn³⁺, which was beneficial to ion diffusion and electronic conductivity. As a result, this LNMO cathode material had an optimized electrochemical rate performance of 105.6 mAh g⁻¹ at 1 C and cycling stability of 116.8 mAh g⁻¹ at 0.1 C after 100 cycles.