Shi Yaru, Liu Yiqian, Ma Tengzhou, Hu Xiongtao, Liu Xiaoyu, Jiang Yong, Li Wenrong, Zhang Jiujun, Zhao Bing
School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.
Shanghai Customs Industrial Products and Raw Materials Testing Technology Center, Shanghai 200135, China.
J Colloid Interface Sci. 2023 Jul;641:470-478. doi: 10.1016/j.jcis.2023.03.090. Epub 2023 Mar 16.
The garnet LiLaZrTaO (LLZTO) is one of the most promising electrolytes for commercial application since of its high ionic conductivity and good stability to Li. Nevertheless, the poor electrolyte/electrode interface contact enlarges the interface impedance of all-solid-state battery (ASSB). Herein, a multifunctional polymer electrolyte (MPE) interface buffer layers are formed on both sides of LLZTO surface through an in-situ crosslinking strategy to improve the interface contact with electrodes, which can facilitate uniform Li deposition/exfoliation and inhibit the growth of lithium dendrites as evidenced by the reduced interface impedance (103.4 Ω cm), the increased critical current density (CDD, 1.2 mA cm) and 950 h stable cycle of Li symmetric cells at 0.7 mA cm, 0.7 mA h cm. Besides, the MPE layer can reduce the magnitude of electric field at the interface and widen the electrochemical window (0∼5.2 V). The stable interface of the LLZTO@MPE/cathode enables the full cells matching with the LiFePO (LFP) and LiNiCoMnO (NCM523) cathodes to deliver superior electrochemical performances. Specifically, the Li/MPE@LLZTO@MPE/LFP delivers a capacity retention rate of 87% after 200 cycles at 1 C. When it's matched with the NCM523 cathode, a capacity retention rate of 98% is retained after 100 cycles at 1 C. This work provides an effective and simple way to build good-interface-contact and long-lifespan garnet solid-state lithium metal batteries (SSLMBs).
石榴石型LiLaZrTaO（LLZTO）因其高离子电导率和对锂的良好稳定性，是最具商业应用前景的电解质之一。然而，电解质与电极之间不良的界面接触会增大全固态电池（ASSB）的界面阻抗。在此，通过原位交联策略在LLZTO表面两侧形成多功能聚合物电解质（MPE）界面缓冲层，以改善与电极的界面接触，这有助于锂的均匀沉积/剥离，并抑制锂枝晶的生长，这可由降低的界面阻抗（103.4Ω·cm）、增加的临界电流密度（CDD，1.2mA/cm²）以及锂对称电池在0.7mA/cm²、0.7mAh/cm²下950小时的稳定循环得到证明。此外，MPE层可降低界面处的电场强度，并拓宽电化学窗口（0至5.2V）。LLZTO@MPE/阴极的稳定界面使与LiFePO（LFP）和LiNiCoMnO（NCM523）阴极匹配的全电池具有优异的电化学性能。具体而言，Li/MPE@LLZTO@MPE/LFP在1C下循环200次后容量保持率为87%。当它与NCM523阴极匹配时，在1C下循环100次后容量保持率为98%。这项工作提供了一种有效且简单的方法来构建具有良好界面接触和长寿命的石榴石型固态锂金属电池（SSLMBs）。
