In-Situ Polymerized High-Voltage Solid-State Lithium Metal Batteries with Dual-Reinforced Stable Interfaces
Qiang Lv, Cheng Li, Yue Liu, Yutong Jing, Jianguo Sun, Haimei Wang, Lei Wang, Huaizheng Ren, Bochen Wu, Tao Cheng, Dianlong Wang, Huan Liu, Shi Xue Dou, Bo Wang, John Wang
Abstract
Solid polymer electrolytes (SPEs) represent a pivotal advance toward high-energy solid-state lithium metal batteries. However, inadequate interfacial contact remains a significant bottleneck, impeding scalability and application. Inadequate interfacial contact remains a significant bottleneck, impeding scalability and application. Recent efforts have focused on transforming liquid/solid interfaces into solid/solid ones through in situ polymerization, which shows potential especially in reducing interface impedance. Here, we designed high-voltage SSLMBs with dual-reinforced stable interfaces by combining interface modification with an in situ polymerization technology inspired by targeted effects in medicine. Theoretical calculations and time-of-flight secondary ion mass spectrometry (TOF-SIMS) analysis demonstrate that tetramethylene sulfone (TMS) and bis(2,2,2-trifluoromethyl) carbonate (TFEC) exhibit selective adsorption at the interface of the LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM) cathode and Li anode, respectively. These compounds further decompose to form a stable cathode–electrolyte interface (CEI) film and a solid electrolyte interface (SEI) film, thereby simultaneously achieving a superior interface between the SPE and both the Li anode and NCM cathode. The developed Li||SPE||Li cell sustained cycling for more than 1000 h at 0.3 mA cm –2, and the NCM||SPE||Li cell also demonstrated an excellent capacity retention of 86.8% after 1000 cycles at 1 °C. This work will provide valuable insights for the rational design of high-voltage SSLMBs with stable interfaces, leveraging in situ polymerization as a cornerstone technology.