The cathode electrodes in commercial Li-ion cells are usually coated on aluminum foils, while the anode part is coated on copper current collector. However, these metallic foils of the electrodes are relatively heavy counterparts when compared with the total cell weight. To overcome this issue, we comparatively studied LiNi 1/3 Mn 1/3 Co 1/3 O 2 (NMC); NMC/graphene positive electrodes reinforced with graphene were produced in the form of freestanding electrodes by a facile sol-gel and vacuum filtration method. To confirm our results obtained with the half-cells, graphite@NMC@graphene full-cells were also produced and a specific capacity of 220 mAh g −1 after 250 cycles. Extraordinary electrochemical cycling, high conductivity, and enhanced rate properties are obtained by anchoring the NMC particles between the graphene layers. The results have also indicated that the freestanding graphene-based electrodes could be a useful tool for high-capacity lithium-ion batteries.

Significant climate change and variable fossil energy prices are forcing us to minimize fossil fuel consumption and develop innovative energy conversion and storage systems capable of reducing carbon dioxide emissions. Batteries are the most common form of alternative energy systems, and cathode materials are critical for their performance. Their low-rate performance and short lifespan severely hamper the efficiency of cathode materials. The adoption of nanotechnology is essential to improve the cathode life cycle and maintain capacity. Conventional synthetic techniques face serious problems in producing complex nanomaterials with precise design, high efficiency, and long life. Recent efforts have been made to utilize bio-inspired materials in a variety of applications, emphasizing the importance of biomimetics due to their unique advantages and excellent properties. This review examines the synthesis mechanism, properties, and advances of bioinspired materials in the production of nanomaterials in order to pave the way for the future study of rechargeable batteries. Subsequently, the solutions and problems encountered by cathode materials in the main categories of secondary rechargeable batteries are addressed. The aim of this study is to alert scientists toward this promising development trend in bio-inspired battery materials.

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Herein, silicon nanoparticles (nSi) are produced by magnesiothermic reduction methods. nSi are then obtained in the form of a 3D graphene aerogel (GA), prepared by a simple one‐step freeze‐drying process using L‐ascorbic acid. By a simple freeze‐drying process, nSi is neatly decorated between sheets of graphene. GA forms a conductive structure for nSi whose mechanical mesh acts as a buffer layer. This conductive structure greatly improves the structural integrity and conductivity of the anode material. Nanoparticles silicon/graphene aerogel (nSi/GA) nanocomposite is investigated by X‐ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and X‐ray photoelectron spectroscopy. nSi/GA nanocomposite demonstrates a superior capacity of 550 mAh g−1 after 500th cycle. As a result, the nSi/GA anodes show improvement in cycling stability compared with pure nSi. Tests are conducted at different rate capability to measure the velocity characteristic and the resulting anode exhibits average specific discharge capacities of 1217, 976, 919, 825, 674, and 572 mAh g−1 at charge/discharge rates of C/20, C/10. C/5, 1C, 3C, and 5C, respectively. Benefiting from easy synthesis and excellent cyclic stability, nSi/GA are expected to play an important role in the lithium‐ion battery.