Feng Wuliang, Hu Jiaming, Qian Guannan, Xu Zhenming, Zan Guibin, Liu Yijin, Wang Fei, Wang Chunsheng, Xia Yongyao
Department of Chemistry, Department of Materials Science, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200433, China.
Department of Physics, Fudan University, Shanghai 200433, China.
Sci Adv. 2022 Oct 21;8(42):eadd8972. doi: 10.1126/sciadv.add8972. Epub 2022 Oct 19.
The high interfacial resistance and lithium (Li) dendrite growth are two major challenges for solid-state Li batteries (SSLBs). The lack of understanding on the correlations between electronic conductivity and Li dendrite formation limits the success of SSLBs. Here, by diluting the electronic conductor from the interphase to bulk Li during annealing of the aluminium nitride (AlN) interlayer, we changed the interphase from mixed ionic/electronic conductive to solely ionic conductive, and from lithiophilic to lithiophobic to fundamentally understand the correlation among electronic conductivity, Li dendrite, and interfacial resistance. During the conversion-alloy reaction between AlN and Li, the lithiophilic and electronic conductive LiAl diffused into Li, forming a compact lithiophobic and ionic conductive LiN, which achieved an ultrahigh critical current density of 2.6/14.0 mA/cm in the time/capacity-constant mode, respectively. The fundamental understanding on the effect of interphase nature on interfacial resistance and Li dendrite suppression will provide guidelines for designing high-performance SSLBs.
高界面电阻和锂枝晶生长是固态锂电池（SSLBs）面临的两大主要挑战。对电子电导率与锂枝晶形成之间相关性的认识不足限制了固态锂电池的成功。在此，通过在氮化铝（AlN）中间层退火过程中从界面到块状锂稀释电子导体，我们将界面从混合离子/电子导电转变为仅离子导电，从亲锂转变为疏锂，从而从根本上理解电子电导率、锂枝晶和界面电阻之间的相关性。在AlN与锂之间的转化合金反应过程中，亲锂且导电的LiAl扩散到锂中，形成致密的疏锂且离子导电的LiN，在时间/容量恒定模式下分别实现了2.6/14.0 mA/cm的超高临界电流密度。对界面性质对界面电阻和锂枝晶抑制作用的基本理解将为设计高性能固态锂电池提供指导。
