High-energy-density lithium metal battery systems have been attracting significant attention, but their serious safety and stability issues due to the growth of lithium dendrites and strong chemical reactivity of Li metal hinder their practical application. Fortunately, polymer electrolytes may allow lithium metal batteries to flourish. Usually, polymer electrolytes can be divided into dry polymer electrolytes and gel polymer electrolytes. Firstly, we review dry polymer electrolytes based on different polymer materials. This type of electrolyte usually suffers from insufficient room-temperature ionic conductivity and poor interfacial compatibility with electrodes. Thus, many meaningful approaches have been proposed to overcome these issues. Secondly, we review the formulation and development of gel polymer electrolytes. Although some gel polymer electrolytes show excellent lithium ionic conductivity, their mechanical properties are insufficient. Thus, many efforts, including blending, copolymerization, crosslinking and addition of inorganic particles, have been made to address these issues to achieve strong mechanical strength and superior electrochemical performances. Thirdly, special functional polymer electrolytes can solve some pivotal problems to further improve the battery performance. We review some special functional polymer electrolytes such as non-flammable polymer electrolytes, polymer electrolytes for the shuttle inhibition of polysulfides and manganese (Mn²⁺), and self-healing polymer electrolytes. Finally, the developing trends and challenges of polymer electrolytes are analyzed to foresee the promising future of rechargeable lithium metal batteries based on polymer electrolytes.

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可充电锂金属电池的聚合物电解质

高能量密度锂金属电池系统已经引起了广泛的关注，但是由于锂树枝状晶体的生长以及锂金属的强化学反应性导致其严重的安全性和稳定性问题阻碍了其实际应用。幸运的是，聚合物电解质可以使锂金属电池蓬勃发展。通常，聚合物电解质可分为干聚合物电解质和凝胶聚合物电解质。首先，我们回顾了基于不同聚合物材料的干聚合物电解质。这类电解质通常遭受室温离子电导率不足和与电极的界面相容性差的问题。因此，已经提出了许多有意义的方法来克服这些问题。其次，我们回顾了凝胶聚合物电解质的配方和开发。尽管一些凝胶聚合物电解质显示出优异的锂离子传导性，但是它们的机械性能不足。因此，已经进行了许多努力，包括共混，共聚，交联和添加无机颗粒，以解决这些问题，以获得强大的机械强度和优异的电化学性能。第三，特殊功能的聚合物电解质可以解决一些关键问题，从而进一步提高电池性能。我们回顾了一些特殊的功能性聚合物电解质，例如不易燃的聚合物电解质，用于抑制多硫化物和锰（Mn 已经进行了交联和无机颗粒的添加以解决这些问题，以获得强大的机械强度和优异的电化学性能。第三，特殊功能的聚合物电解质可以解决一些关键问题，从而进一步提高电池性能。我们回顾了一些特殊的功能性聚合物电解质，例如不易燃的聚合物电解质，用于抑制多硫化物和锰（Mn 已经进行了交联和无机颗粒的添加以解决这些问题，以获得强大的机械强度和优异的电化学性能。第三，特殊功能的聚合物电解质可以解决一些关键问题，从而进一步提高电池性能。我们回顾了一些特殊的功能性聚合物电解质，例如不易燃的聚合物电解质，用于抑制多硫化物和锰（Mn²⁺）和自修复的聚合物电解质。最后，分析了聚合物电解质的发展趋势和挑战，以预见基于聚合物电解质的可再充电锂金属电池的有前途的未来。