Coupling thin Li metal anodes with high-capacity/high-voltage cathodes such as LiNi_0.8Co_0.1Mn_0.1O₂ (NCM811) is a promising way to increase lithium battery energy density. Yet, the realization of high-performance full cells remains a formidable challenge. Here, we demonstrate a new class of highly coordinated, nonflammable carbonate electrolytes based on lithium bis(fluorosulfonyl)imide (LiFSI) in propylene carbonate/fluoroethylene carbonate mixtures. Utilizing an optimal salt concentration (4 M LiFSI) of the electrolyte results in a unique coordination structure of Li⁺-FSI⁻-solvent cluster, which is critical for enabling the formation of stable interfaces on both the thin Li metal anode and high-voltage NCM811 cathode. Under highly demanding cell configuration and operating conditions (Li metal anode = 35 μm, areal capacity/charge voltage of NCM811 cathode = 4.8 mAh cm⁻²/4.6 V, and anode excess capacity [relative to the cathode] = 0.83), the Li metal-based full cell provides exceptional electrochemical performance (energy densities = 679 Wh kg_cell⁻¹/1,024 Wh L_cell⁻¹) coupled with nonflammability.

将薄的锂金属阳极与高容量/高电压阴极（例如LiNi _0.8 Co _0.1 Mn _0.1 O ₂（NCM811））耦合是提高锂电池能量密度的一种有前途的方法。然而，高性能全电池的实现仍然是一个巨大的挑战。在这里，我们展示了基于碳酸亚丙酯/碳酸氟亚乙酯混合物中的双（氟磺酰基）酰亚胺锂（LiFSI）的一类新型的高度配位，不可燃的碳酸酯电解质。利用该电解质的结果的最佳盐浓度（4M的LiFSI）在锂的独特配位结构⁺ -FSI ^--溶剂簇，这对于在薄的锂金属阳极和高压NCM811阴极上形成稳定的界面至关重要。在苛刻的电池配置和操作条件下（Li金属阳极= 35μm，NCM811阴极的面积容量/充电电压= 4.8 mAh cm ^-2 /4.6 V，阳极过剩容量[相对于阴极] = 0.83），金属基全电池可提供出色的电化学性能（能量密度= 679 Wh kg_电池^-1 / 1,024 Wh L_电池^-1），并且具有不可燃性。