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Developing electrode materials for high-performance secondary batteries is one of the most effective approaches to alleviate energy and environmental crises. Nowadays, graphite anodes, which are widely used in commercial lithium-ion batteries, cannot satisfy the ever-growing energy needs of humans owing to their relatively low theoretical capacities and nearly no capacity in sodium-ion batteries. Therefore, developing new anodes with high capacity and energy density is necessary for next-generation large-scale energy systems. Red phosphorus has become an interesting topic in alkali-ion battery research and is expected to be commercially used as anode material in the next generation of secondary batteries owing to their intrinsic properties, such as their high activity, high theoretical specific capacity (2596 mA∙h∙g−1), suitable oxidation–reduction potential, highly abundant earth resources, and low cost of lithium/sodium-ion batteries. However, red phosphorus exhibits poor electrical conductivity and large volume expansion when used as electrode material, resulting in low utilization of active material, serious electrode pulverization, and poor electrode cycling stability, which seriously hindered their commercial application in next-generation rechargeable batteries. Recent studies have shown that the cycle stability and electronic conductivity of red phosphorus can be improved by rational structural design, which promotes the electrochemical performance of red phosphorus anodes. For example, reducing the material size to the nanoscale can effectively shorten the diffusion path, enhancing the ion diffusion rate while alleviating the volume expansion and pulverization of the active substance. Additionally, the size reduction changes the band energy of the red phosphorus, which can transform indirect into direct bandgap semiconductors. Besides, the external characteristics of the active materials affect the performance by reducing the internal stress generated by the phase transformation in charging and discharging cycles. By modifying the morphology and structure of red phosphorus to form porous, layer, hollow, or composite structures, the cyclability and chargeability of batteries could be optimized because the internal stress generated by the volume change of the active material can be effectively released, and the generation probability of cracks or fractures in the electrode is drastically reduced. Therefore, these strategies help alleviate electrode pulverization and promote the commercial application of red phosphorus in lithium/sodium-ion batteries. Herein, we review the recent research progress in controllable synthesis, structural design, and performance optimization mechanisms of red phosphorus-based nanocomposites. Finally, we summarize the challenges in current research on red phosphorus anode materials, propose potential solutions, and provide an outlook on the future development of red phosphorus-based anode materials in the energy storage system.

The integrated energy system (IES) includes various energy forms, complex operation modes, abundant control equipment and coupling links, which brings challenges to its steady-state modeling and steady-state power flow calculation. In order to obtain the steady-state characteristics of the thermal subsystem in the IES, the topological structure of the typical IES was provided; the steady-state models of the power subsystem, the thermal subsystem, the cold subsystem and the distributed energy station were established respectively, and then the hybrid power flow model was established, and the Newton-Raphson algorithm was used to solve the hybrid power flow; the influence of the key technical parameters (including the water supply temperature of the source node, the water outlet temperature of the load node, the length and diameter of the heat network pipe, and the heat load power) on the steady-state power flow of the IES was analyzed. The analysis results can support the planning, design and optimal operation of the IES.