All-solid-state sodium-ion batteries are promising candidates for large-scale energy storage applications. The key enabler for an all-solid-state architecture is a sodium solid electrolyte that exhibits high Na+ conductivity at ambient temperatures, as well as excellent phase and electrochemical stability. In this work, we present a first-principles-guided discovery and synthesis of a novel Cl-doped tetragonal Na3PS4 (t-Na3−xPS4−xClx) solid electrolyte with a room-temperature Na+ conductivity exceeding 1 mS cm−1. We demonstrate that an all-solid-state TiS2/t-Na3−xPS4−xClx/Na cell utilizing this solid electrolyte can be cycled at room-temperature at a rate of C/10 with a capacity of about 80 mAh g−1 over 10 cycles. We provide evidence from density functional theory calculations that this excellent electrochemical performance is not only due to the high Na+ conductivity of the solid electrolyte, but also due to the effect that “salting” Na3PS4 has on the formation of an electronically insulating, ionically conducting solid electrolyte interphase.
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机译:全固态钠离子电池是大规模储能应用的有希望的候选者。全固态体系结构的关键推动因素是钠固体电解质,该钠固体电解质在环境温度下具有很高的Na + sup>电导率,并且具有出色的相和电化学稳定性。在这项工作中,我们提出了第一原理指导的发现和合成新型的Cl掺杂的四方Na3PS4(t-Na3-xPS4-xClx)固体电解质,其室温Na + sup>电导率超过1 mS cm -1 sup>。我们证明,利用这种固体电解质的全固态TiS2 / t-Na3-xPS4-xClx / Na电池可以在室温下以C / 10的速率循环,容量约为80 mAh g -1 sup>超过10个周期。我们从密度泛函理论计算中提供了证据,表明这种出色的电化学性能不仅是由于固体电解质的高Na + sup>电导率,还归因于“盐化” Na3PS4对地层的影响。电子绝缘的,离子导电的固体电解质界面。
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