Zheng Jingxu, Archer Lynden A
Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States.
Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Chem Rev. 2022 Sep 28;122(18):14440-14470. doi: 10.1021/acs.chemrev.2c00022. Epub 2022 Aug 11.
The vast of majority of battery electrode materials of contemporary interest are of a crystalline nature. Crystals are, by definition, anisotropic from an atomic-structure perspective. The inherent structural anisotropy may give rise to favored mesoscale orientations and anisotropic properties whether the material is in a rest state or subjected to an external stimulus. The overall perspective of this review is that intentional manipulation of crystallographic anisotropy of electrochemically active materials constitute an untapped parameter space in energy storage systems and thus provide new opportunities for materials innovations and design. To that end, we contend that crystallographically textured electrodes, as opposed to their textureless poly crystalline or single-crystalline analogs, are promising candidates for next-generation storage of electrical energy in rechargeable batteries relevant to commercial practice. This perspective is underpinned first by the fundamental─to a first approximation─uniaxial, rotation-invariant symmetry of electrochemical cells. On this basis, we show that a crystallographically textured electrode with the preferred orientation aligned out-of-plane toward the counter electrode represents an optimal strategy for utilization of the crystals' anisotropic properties. Detailed analyses of anisotropy of different types lead to a simple, but potentially useful general principle that "//" textures are optimal for metal anodes, and "//" textures are optimal for insertion-type electrodes.
当代备受关注的绝大多数电池电极材料都具有晶体性质。从定义上讲，晶体从原子结构角度来看是各向异性的。无论材料处于静止状态还是受到外部刺激，其固有的结构各向异性都可能导致有利的中尺度取向和各向异性特性。本综述的总体观点是，对电化学活性材料的晶体各向异性进行有意操控，构成了储能系统中一个尚未开发的参数空间，从而为材料创新和设计提供了新机遇。为此，我们认为，与无织构的多晶或单晶类似物相比，具有晶体织构的电极是与商业实践相关的可充电电池中下一代电能存储的有前途的候选材料。这一观点首先基于电化学电池基本的（一阶近似）单轴、旋转不变对称性。在此基础上，我们表明，具有择优取向且面外朝向对电极排列的晶体织构电极是利用晶体各向异性特性的最佳策略。对不同类型各向异性的详细分析得出一个简单但可能有用的一般原则，即“//”织构对金属阳极是最佳选择，而“//”织构对插入型电极是最佳选择。
