Lithium-Conducting Branched Polymers: New Paradigm of Solid-State Electrolytes for Batteries

The past decades have witnessed rapid development of lithium-based batteries. Significant research efforts have been progressively diverted from electrodes to electrolytes, particularly polymer electrolytes (PEs), to tackle the safety concern and promote the energy storage capability of batteries. To further increase the ionic conductivity of PEs, various branched polymers (BPs) have been rationally designed and synthesized. Compared with linear polymers, branched architectures effectively increase polymer segmental mobility, restrain crystallization, and reduce chain entanglement, thereby rendering BPs with greatly enhanced lithium transport. In this Mini Review, a diversity of BPs for PEs is summarized by scrutinizing their unique topologies and properties. Subsequently, the design principles for enhancing the physical properties, mechanical properties, and electrochemical performance of BP-based PEs (BP-PEs) are provided in which the ionic conduction is particularly examined in light of the Li+ transport mechanism. Finally, the challenges and future prospects of BP-PEs in this rapidly evolving field are outlined.

过去几十年见证了锂电池的快速发展。大量的研究工作逐渐从电极转向电解质，尤其是聚合物电解质（PEs），以解决安全问题并提高电池的储能能力。为了进一步提高聚合物电解质的离子电导率，人们合理设计并合成了各种支化聚合物（BPs）。与线性聚合物相比，支化结构有效地提高了聚合物链段的迁移率，抑制了结晶，并减少了链缠结，从而使支化聚合物的锂传输能力大大增强。在这篇小综述中，通过仔细研究其独特的拓扑结构和性质，总结了多种用于聚合物电解质的支化聚合物。随后，提出了增强基于支化聚合物的聚合物电解质（BP - PEs）的物理性能、机械性能和电化学性能的设计原则，其中根据锂离子传输机制对离子传导进行了特别研究。最后，概述了BP - PEs在这个快速发展的领域中面临的挑战和未来前景。