Kim Cham, Yang Yeokyung, Ha Dongwoo, Kim Dong Hwan, Kim Hoyoung
Daegu Gyeongbuk Institute of Science and Technology (DGIST) 333 Techno Jungang-daero Daegu 42988 Republic of Korea
Korea Electrotechnology Research Institute (KERI) 12 Bulmosan-ro 10beon-gil Changwon Gyeongsangnam-do 51543 Republic of Korea.
RSC Adv. 2019 Oct 8;9(55):31936-31942. doi: 10.1039/c9ra05284d. eCollection 2019 Oct 7.
We suggest a way to control the crystal orientation of LiFePO using a magnetic field to obtain an advantageous structure for lithium ion conduction. We examined the magnetic properties of LiFePO such as magnetism and magnetic susceptibility, which are closely related to the crystal rotation in an external magnetic field, and considered how to use these properties for desired crystal orientation; thus, we successfully fabricated the crystal-aligned LiFePO, in which the -axis was highly aligned perpendicular to the surface of a current collector. Considering the low lithium ion conductivity of LiFePO inherently originated from its one-dimensional path for lithium ion diffusion, the crystal-aligned LiFePO potentially facilitates favorable transport kinetics for lithium ions during the charge/discharge process in lithium ion batteries. The crystal-aligned LiFePO should afford lower electrode polarization than pristine LiFePO, and thus the former consistently exhibited higher reversible capacity than the latter.
我们提出了一种利用磁场控制磷酸铁锂晶体取向的方法，以获得有利于锂离子传导的结构。我们研究了磷酸铁锂的磁性和磁化率等磁性能，这些性能与外部磁场中的晶体旋转密切相关，并考虑了如何利用这些性能实现所需的晶体取向；因此，我们成功制备了晶体取向排列的磷酸铁锂，其中c轴高度垂直于集流体表面排列。考虑到磷酸铁锂固有的低锂离子电导率源于其锂离子扩散的一维路径，晶体取向排列的磷酸铁锂在锂离子电池的充电/放电过程中可能有助于锂离子实现良好的传输动力学。晶体取向排列的磷酸铁锂应比原始磷酸铁锂具有更低的电极极化，因此前者始终表现出比后者更高的可逆容量。
