Yan Lv, Qin Jieming, Liang Benkuan, Gao Shanlin, Wang Bo, Cui Jiuyue, Bolag Altan, Yang Yanchun
School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun, 130022, P. R. China.
School of Physics and Electronic Information, Inner Mongolia Normal University, Hohhot, 010022, P. R. China.
Small. 2022 Sep;18(35):e2202901. doi: 10.1002/smll.202202901. Epub 2022 Aug 5.
Lithium-ion battery based on LiCrTiO (LCTO) is considered to be a promising anode material, as they provide higher safety and durability beyond than that of graphite electrode. However, the applications of this transformative technology demand improved inherent electrical conductivity of LCTO as well as a simple and rapid synthetic route. Here, LCTO with oxygen vacancies (OVs) is fabricated using high-pressure synthesis technology in only 40 min. The optimal synthesis pressure is 0.8 GPa (LCTO-0.8). The reversible capacity of LCTO-0.8 at 1C is 131 mA h g after 1000 cycles and the capacity retention is nearly 97%, and the reversible capacity of LCTO synthesized at atmospheric pressure (LCTO-P) is 85 mA h g under the same circumstances. Even at 5C, the reversible capacity is 110 mA h g , which is 77% higher than LCTO-P. Furthermore, it is confirmed by theoretical calculations that the introduction of OVs has the occupation of electronic states at the Fermi level, which greatly enhances the intrinsic conductivity of LCTO. Specifically, the electronic conductivity has increased by two orders of magnitude compared with LCTO-P. Therefore, high-pressure synthesis technology endows LCTO with superior characteristics, providing a new avenue for industrialization.
基于LiCrTiO(LCTO)的锂离子电池被认为是一种很有前景的负极材料,因为它们比石墨电极具有更高的安全性和耐久性。然而,这种变革性技术的应用需要提高LCTO固有的电导率以及一条简单快速的合成路线。在此,采用高压合成技术仅在40分钟内就制备出了具有氧空位(OVs)的LCTO。最佳合成压力为0.8 GPa(LCTO-0.8)。LCTO-0.8在1C下1000次循环后的可逆容量为131 mA h g,容量保持率接近97%,而在相同条件下常压合成的LCTO(LCTO-P)的可逆容量为85 mA h g。即使在5C时,可逆容量仍为110 mA h g,比LCTO-P高77%。此外,理论计算证实,氧空位的引入占据了费米能级的电子态,这大大提高了LCTO的本征电导率。具体而言,与LCTO-P相比,电子电导率提高了两个数量级。因此,高压合成技术赋予了LCTO优异的特性,为工业化提供了一条新途径。