Fang Hong, Jena Puru
Department of Physics, Virginia Commonwealth University, Richmond, VA, USA.
Nat Commun. 2022 Apr 19;13(1):2078. doi: 10.1038/s41467-022-29769-5.
Development of next-generation solid-state Li-ion batteries requires not only electrolytes with high room-temperature (RT) ionic conductivities but also a fundamental understanding of the ionic transport in solids. In spite of considerable work, only a few lithium conductors are known with the highest RT ionic conductivities ~ 0.01 S/cm and the lowest activation energies ~0.2 eV. New design strategy and novel ionic conduction mechanism are needed to expand the pool of high-performance lithium conductors as well as achieve even higher RT ionic conductivities. Here, we theoretically show that lithium conductors with RT ionic conductivity over 0.1 S/cm and low activation energies ~ 0.1 eV can be achieved by incorporating cluster-dynamics into an argyrodite structure. The extraordinary superionic metrics are supported by conduction mechanism characterized as a relay between local and long-range ionic diffusions, as well as correlational dynamics beyond the paddle-wheel effect.
下一代固态锂离子电池的发展不仅需要具有高室温（RT）离子电导率的电解质，还需要对固体中的离子传输有基本的了解。尽管已经开展了大量工作，但目前已知的锂导体中，只有少数具有最高的室温离子电导率0.01 S/cm和最低的活化能0.2 eV。需要新的设计策略和新颖的离子传导机制来扩大高性能锂导体的范围，并实现更高的室温离子电导率。在此，我们从理论上表明，通过将团簇动力学引入硫银锗矿结构，可以实现室温离子电导率超过0.1 S/cm且活化能低至~0.1 eV的锂导体。这种非凡的超离子指标得到了传导机制的支持，该传导机制的特征是局部和长程离子扩散之间的接力，以及超越桨轮效应的关联动力学。
