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With the urgent market demand for high-energy-density batteries, the alloy-type or conversion-type anodes with high specific capacity have gained increasing attention to replace current low-specific-capacity graphite-based anodes. However, alloy-type and conversion-type anodes have large initial irreversible capacity compared with graphite-based anodes, which consume most of the Li+ in the corresponding cathode and severely reduces the energy density of full cells. Therefore, for the practical application of these high-capacity anodes, it is urgent to develop a commercially available prelithiation technique to compensate for their large initial irreversible capacity. At present, various prelithiation methods for compensating the initial irreversible capacity of the anode have been reported, but due to their respective shortcomings, large-scale commercial applications have not yet been achieved. In this review, we have systematically summarized and analyzed the advantages and challenges of various prelithiation methods, providing enlightenment for the further development of each prelithiation strategy toward commercialization and thus facilitating the practical application of high-specific-capacity anodes in the next-generation high-energy-density lithium-ion batteries.

Three-dimensional (3D) graphene oxide/polypyrrole (GO/PPy) composite electrodes have been fabricated via a one-step electrochemical co-deposition in an aqueous solution containing pyrrole monomer, GO and LiClO 4 . The concentration of GO in the solution plays an important role in controlling the morphologies of the as-deposited GO/PPy composites, and a relatively low concentration as 0.1 mg mL −1 is favorable for the formation of 3D interconnected structure. The unique 3D interconnected structure assures fast diffusion of electrolyte ions through the electrode. As a result, the GO/PPy composite electrode with a mass loading of 0.26 mg cm −2 exhibits the highest specific capacitance of 481.1 F g −1 , while the electrode with a larger mass loading of 1.02 mg cm −2 delivers the best area capacitance of 387.6 mF cm −2 , at a current density of 0.2 mA cm −2 . Moreover, the GO/PPy composite electrodes exhibit good rate capability with capacitance retentions over 80% when the current density load increases from 0.2 to 10 mA cm −2 . Both of the aqueous and solid-state supercapacitors based on GO/PPy composite electrodes show excellent capacitive properties with good cycling stability, indicating their suitability for applications in energy storage and management.

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