Balancing stability and specific energy in Li-rich cathodes for lithium ion batteries: a case study of a novel Li–Mn–Ni–Co oxide
Artikel i vetenskaplig tidskrift, 2015

Lithium batteries for UPS, portable electronics and electrical vehicles rely on high-energy cathodes. Li-rich manganese-rich oxide (xLi2MnO3·(1 − x)LiMO2, M = transition metals) is one of the few materials that might meet such a requirement, but it suffers from poor energy retention due to serious voltage and/or capacity fade, which challenges its applications. Here we show that this challenge can be addressed by optimizing the interactions between the components Li2MnO3 and LiMO2 in the Li-rich oxide (i.e. stabilizing the layered structure through Li2MnO3 and controlling Li2MnO3 activation through LiMO2). To realize this synergistic effect, a novel Li2MnO3-stabilized Li1.080Mn0.503Ni0.387Co0.030O2 was designed and prepared using a hierarchical carbonate precursor obtained by a solvo/hydro-thermal method. This layered oxide is demonstrated to have a high working voltage of 3.9 V and large specific energy of 805 W h kg−1 at 29 °C as well as impressive energy retention of 92% over 100 cycles. Even when exposed to 55 °C, energy retention is still as high as 85% at 200 mA g−1. The attractive performance is most likely the consequence of the balanced stability and specific energy in the present material, which is promisingly applicable to other Li-rich oxide systems. This work sheds light on harnessing Li2MnO3 activation and furthermore efficient battery design simply through compositional tuning and temperature regulation.

Författare

Qi Li

Chalmers, Mikroteknologi och nanovetenskap (MC2)

Guangshe Li

Chaochao Fu

Dong Luo

Jianming Fan

Dongjiu Xie

Liping Li

Journal of Materials Chemistry

0959-9428 (ISSN) 1364-5501 (eISSN)

Vol. 3 10592-10602

Ämneskategorier

Materialteknik