All-solid-state electrolytes are widely understood to be required for energy-dense storage/conversion devices. Persistent problems associated with low ionic conductivity, poor charge transport across explicit and implicit interfaces, and inferior chemical stability continue to pose significant barriers to progress. Here, we synthesize and study a series of gel (or “quasi-solid-state”) electrolytes that can overcome many of the known limitations of their all-solid-state analogs. We discover that in two physical states, solvent-in-polymer (SIP) and polymer-in-solvent (PIS), the electrolytes offer exceptional ion-transport and stability characteristics. In both states, crystallization of the polymer component and thermodynamic activity of the solvent are lowered, allowing the electrolytes to achieve attractive combinations of ion transport, thermal, and electrochemical stability. Moreover, the SIP-PIS electrolytes can be in situ polymerized inside an electrochemical cell, resulting in fast kinetics for LiNi_0.8Mn_0.1Co_0.1O₂ cathode with areal capacity of 2.5 mAh/cm² and long-term stability toward lithium metal anode over 1,200 h.

人们普遍认为，全固态电解质是能量密集型存储/转换设备所必需的。与离子电导率低，电荷在显式和隐式界面上的迁移较差以及化学稳定性较差有关的持久性问题继续对进步构成重大障碍。在这里，我们合成并研究了一系列凝胶（或“准固态”）电解质，这些电解质可以克服其全固态类似物的许多已知局限性。我们发现，在两种物理状态（聚合物中的溶剂（SIP）和聚合物中的溶剂（PIS））下，电解质具有出色的离子传输和稳定性特征。在这两种状态下，聚合物组分的结晶和溶剂的热力学活性均降低，从而使电解质能够实现离子迁移，传热，和电化学稳定性。此外，SIP-PIS电解质可以是在电化学电池内原位聚合，可得到LiNi _0.8 Mn _0.1 Co _0.1 O ₂阴极的快速动力学，其阴极容量为2.5 mAh / cm ^2，并且在1200 h内对锂金属阳极具有长期稳定性。