Qing Piao, Huang Shaozhen, Naren Tuoya, Li Quan, Huang Haifeng, Long Kecheng, Liu Zhijian, Mei Lin, Sun Fu, Wei Weifeng, Zhang Yu, Ma Jianmin, Wu Zhibin, Chen Libao
State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China; National Energy Metal Resources and New Materials Key Laboratory, Central South University, Changsha 410083, China.
State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China.
Sci Bull (Beijing). 2024 Sep 30;69(18):2842-2852. doi: 10.1016/j.scib.2024.07.021. Epub 2024 Jul 15.
Host-less lithium metal anode generally suffers from large volume changes and serious dendrite growth during cycling, which poses challenges for its practical application. Interpenetrating phase composites with continuous architectures offer a solution to enhance mechanical properties of materials. Herein, a robust composite Li anode (LBN) material is fabricated through the metallurgical reaction between Li and hexagonal boron nitride (h-BN) with the formation of interpenetrating LiB/LiBN phases. As LiB fibers are anchored by LiBN granules, the collapse and slippage of LiB fibers are suppressed whilst the mechanical strength and structural stability of LBN are reinforced. By rolling, ultrathin (15 μm), freestanding, and electrochemically stable LBN foil can be obtained. The LBN anode exhibits a high average Coulombic efficiency of 99.69% (1 mA cm, 3 mAh cm) and a long lifespan of 2500 h (1 mA cm, 1 mAh cm). Notably, the LiCoO (with double-sided load 40 mg cm)|LBN pouch cell can operate over 450 cycles with a capacity retention of 90.1%. The exceptional cycling stability of LBN can be ascribed to the interpenetrating reinforcement architectures and synergistic electronic/ionic conductivity of the LiB/LiBN dual-lithiophilic-phases. This work provides a new methodology for thin Li strip processing and reinforced-architecture design, with implications beyond battery applications.
无主体锂金属负极在循环过程中通常会经历较大的体积变化和严重的枝晶生长，这对其实际应用构成了挑战。具有连续结构的互穿相复合材料为增强材料的机械性能提供了一种解决方案。在此，通过锂与六方氮化硼（h-BN）之间的冶金反应，形成互穿的LiB/LiBN相，制备了一种坚固的复合锂负极（LBN）材料。由于LiB纤维被LiBN颗粒锚固，LiB纤维的坍塌和滑动得到抑制，同时LBN的机械强度和结构稳定性得到增强。通过轧制，可以获得超薄（15μm）、自支撑且电化学稳定的LBN箔。LBN负极在1 mA cm、3 mAh cm条件下表现出99.69%的高平均库仑效率，在1 mA cm、1 mAh cm条件下具有2500 h的长寿命。值得注意的是，LiCoO（双面负载40 mg cm）|LBN软包电池可在450次循环以上运行，容量保持率为90.1%。LBN优异的循环稳定性可归因于LiB/LiBN双亲锂相的互穿增强结构以及协同的电子/离子导电性。这项工作为薄锂带加工和增强结构设计提供了一种新方法，其影响超出了电池应用领域。
