凝胶聚合物电解质用于锂离子电池的研究进展

Research progress on gel polymer electrolytes for lithium-ion batteries

电解质在电化学储能中起着至关重要的作用。在锂离子电池(LIB)中,液体电解质(LE)在几十年的发展中表现出了优异的性能,如高的离子电导率(10-3 S/cm)和与电极良好的接触。然而,LE中的安全问题以及由枝晶生长引起的性能退化严重阻碍了LIB的实际应用。因此,聚合物电解质(PE)有望取代LE。固体聚合物电解质(SPE)虽然有很好的安全性和机械性能,但其受温度限制,离子电导率较低,且与电极接触较差,电池循环性较差。凝胶聚合物电解质(GPE)结合两者的优点,被认为是现有有机液体电解质的有效替代品,它可以用来制造更安全的锂电池。对现有聚合物基体的交联、共聚和混合改性——能够提高电解质的电化学性能的方法进行了综述。同时也对GPE在LIB中的最新研究进展进行了综述,并介绍了新型生物基凝胶电解质基体。最后,展望了制造性能优异的基于GPEs的LIB电池面临的挑战和发展方向。

Electrolytes play a crucial role in electrochemical energy storage.In lithium-ion batteries(LIB),liquid electrolytes(LE)have shown excellent properties over decades of development,such as high ionic conductivity(10-3 S/cm)and good contact with electrodes.However,safety problems in LE and performance degradation caused by dendrite growth seriously hinder the practical application of LIB.Therefore,polymer electrolytes(PE)are expected to replace LE.Although solid polymer electrolyte(SPE)have good safety and mechanical properties,they are limited by temperature,and have low ionic conductivity and poor contact with electrodes,resulting in poor battery circularity.Gel polymer electrolytes(GPEs)combine the advantages of both and are considered an effective alternative to existing organic liquid electrolytes,which can be used to make safer lithium batteries.In this paper,we summarized the existing methods of crosslinking,copolymerization and hybrid modification of polymer matrices to improve the electrochemical performance of electrolytes.At the same time,the latest research progress of GPE in LIB was reviewed,and the novel bio-based gel electrolyte matrices were introduced.Finally,the challenges and development directions of GPEs-based LIB batteries with excellent performance were discussed.