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a variety of renewable energy technologies (based on solar, hydro, wind, geothermal power, etc.), 2) provide power sources for electric and hybrid vehicles for low-carbon or zero-carbon emissions of transportation systems, [3,4] and 3) provide power sources for various portable and wearable electronic devices. Alkali metal (AM) ion batteries (AMIBs) including lithium (Li)-ion batteries (LIBs), sodium (Na)-ion batteries (NIBs), and potassium (K)-ion batteries (KIBs) are important rechargeable battery technologies to support the decarbonization of both electricity supply and transportation systems. Currently dominating the rechargeable battery market is LIBs. NIBs and KIBs are developed as more sustainable alternatives and indeed complements, to mitigate challenges associated with the limited and geopolitically isolated Li resources. [1] Post-alkali metal ion batteries are also pursued such as multivalent ion batteries and lithium sulfur batteries. These battery technologies will not be covered in this review, but have been reviewed elsewhere. [5][6][7][8][9][10][11] The three AMIBs follow the same general cell operation, with variations in material selections (Figure 1). [12][13][14] During charge/discharge the AM ions move via an electrolyte between the cathode (positive electrode) and the anode (negative The development and optimization of high-performance anode materials for alkali metal ion batteries is crucial for the green energy evolution. Atomic scale computational modeling such as density functional theory and molecular dynamics allows for efficient and adventurous materials design from the nanoscale, and have emerged as invaluable tools. Computational modeling cannot only provide fundamental insight, but also present input for multiscale models and experimental synthesis, often where quantities cannot readily be obtained by other means. In this review, an overview of three main anode classes; alloying, conversion, and intercalation-type anodes, is provided and how atomic scale modeling is used to understand and optimize these materials for applications in lithium-, sodium-, and potassium-ion batteries. In the last part of this review, a novel type of anode materials that are largely predicted from density functional theory simulations is presented. These 2D materials are currently in their early stages of development and are only expected to gain in importance in the years to come, both within the battery field and beyond, highlighting the ability of atomic scale materials design.

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Nevertheless, the mostly used graphite anode is gradually unable to meet the evergrowing needs due to its low theoretical capacity (372 mAh g −1 ). [1] Lithium (Li) metal is considered as the "holy grail" of LIBs because of its high theoretical capacity (3860 mAh g −1 ) and the lowest redox potential (−3.04 V vs reversible hydrogen electrode) of all other anodes, [2] but its use in LIBs is limited by its low coulombic efficiency (CE) and safety concerns. At the Li plating/stripping processes, nonuniform Li deposition and tremendous volume changes rupture the fragile solid electrolyte interphase (SEI) film, thus exposing fresh Li to react with the electrolyte and reducing CE. Li preferentially nucleates and grows at the crack of SEI film, and eventually grows into Li dendrites during the constant Li plating/ stripping. Li dendrites tend to become "dead Li" and hence reduce CE. Moreover, Li nucleation and growth will accumulate preferably on the location where local current density is higher than other parts, thus forming dendrites. [3,4] The continuous growth of Li dendrites pierce through the separator and get to the cathode, resulting in the electrical contact and short circuit, which lead to security risk. [5,6] There are many strategies to solve the above problems, including optimization of electrolyte composition, [7] construction of artificial SEI film, [8] diaphragm modification, [9] and modulation of collector structure. According to the Sand's time model, the electrode current density is an important factor affecting Li deposition morphology. [10] Three-dimensional (3D) collectors can effectively reduce the local current density owing to the high surface area. In addition, the 3D interior space can efficiently accommodate deposited Li metal, thus alleviate tremendous volume changes. Based on this principle, a wide variety of current collector, such as copper foam, [11] nickel foam, [12] porous carbon, [13] metal nanowires, [14] carbon tube, [15] carbon cloth, [16] carbon fibers, [17] 3D graphene, [18] and polymeric fiber, [19,20] have been investigated for applications in Li metal batteries. Among them, most 3D current collectors are not only inapplicable for the typical slurry pasting approach, but also detrimental to reducing the weight and size of the cell. [21] Apart from that, most of them are not sufficiently lithiophilic to guide the uniform Li deposition. Especially, copper (Cu) shows a higher overpotential for Li nucleation than the others. [22] Porous carbon-based materials are considered to have great potential Lithium (Li) metal is an excellent anode of Li ion batteries because of its high theoretical capacity and the low redox potential compared to other anodes. However, the uncontrollable growth of Li dendrites still incurs serious safety issues and poor electrochemical performances, leading to its limited practical application. An oxygen and boron codoped honeycomb carbon skeleton (OBHcCs) is reported and a stable Li metal-based anode is realized. It can be coated on a copper foil substrate...

An amorphous ZnP2/C composite with P–C bonds achieves ultralong cycling stability and high rate performance.

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