He Zhiying, Liu Yiwen, Liu Yuankai, Xiao Hecong, Xie Zhengkun, Sheng Chuanchao, Chen Aoyuan, He Ping, Zhou Haoshen
Center of Energy Storage Materials & Technology, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, P. R. China.
College of Chemistry, Zhengzhou University, Zhengzhou 450001, P. R. China.
ACS Nano. 2025 Sep 11. doi: 10.1021/acsnano.5c10768.
All-solid-state batteries (ASSBs) are regarded as a promising route to enhanced safety and energy density through the use of lithium metal anodes. However, lithium dendrite growth and interfacial instability between Li and the solid electrolyte (SE) remain critical bottlenecks. To address these issues, a spontaneously preformed solid electrolyte interphase (PSEI) on the surface of the SE strategy was devised. By incorporating lithium difluoro(oxalato)borate (LiODFB) as a tailored SE additive into LiPSCl, an SEI is engineered that synergistically suppresses dendrite formation, stabilizes the Li/SE interface, and mitigates mechanical degradation. The resulting multifunctional PSEI, which consists of a hybrid organic-inorganic outer layer and an inorganic-rich inner layer, is found to both reduce the electronic conductivity of the SE (thus preventing Li nucleation within SEs) and accommodate mechanical degradation arising from Li plating/stripping to avoid contact loss. Consequently, Li-Li symmetric cells incorporating LPSC with PSEI achieved a critical current density (CCD) of 2.4 mA cm and ultrastable cycling for over 3500 h at 0.2 mA cm. The Li-LiNiCoMnO full cells retained 80% capacity after 310 cycles at 0.5 C and can also operate stably under 4.5 V. This work establishes a rational interface design for SEs that integrates electronic and mechanical modulation with electrochemical stability to unlock the potential of lithium metal anodes in ASSBs.
全固态电池（ASSBs）被认为是通过使用锂金属负极来提高安全性和能量密度的一条有前景的途径。然而，锂枝晶生长以及锂与固体电解质（SE）之间的界面不稳定性仍然是关键瓶颈。为了解决这些问题，设计了一种在SE表面自发形成的固体电解质界面（PSEI）策略。通过将二氟草酸硼酸锂（LiODFB）作为一种定制的SE添加剂掺入LiPSCl中，设计出一种SEI，它能协同抑制枝晶形成，稳定Li/SE界面，并减轻机械降解。所得到的多功能PSEI由有机 - 无机混合外层和富无机内层组成，发现它既能降低SE的电子电导率（从而防止SE内的锂成核），又能适应锂电镀/剥离产生的机械降解以避免接触损失。因此，包含带有PSEI的LPSC的锂 - 锂对称电池在0.2 mA cm下实现了2.4 mA cm的临界电流密度（CCD）和超过3500小时的超稳定循环。锂 - 锂镍钴锰全电池在0.5 C下310次循环后保持80%的容量，并且也能在4.5 V下稳定运行。这项工作为SE建立了一种合理的界面设计，该设计将电子和机械调制与电化学稳定性相结合，以释放ASSBs中锂金属负极的潜力。
