Simultaneous enhancement of electronic and Li+ ion conductivity in LiFePO4

作者：Lee Jaekwang^*; Pennycook Stephen J; Pantelides Sokrates T

来源：Applied Physics Letters, 2012, 101(3): 033901.

DOI：10.1063/1.4737212

Enhancing the electronic and ionic conductivity in Li compounds can significantly impact the design of batteries. Here, we explore the influence of biaxial strain on the electronic and Li+ ion conductivities of LiFePO4 by performing first-principles calculations. We find that 4% biaxial tensile strain (BTS) leads to 15 times increase in electronic conductivity and 50 times increase in Li+ ion conductivity at 300 K, respectively. Electronic conductivity is enhanced because BTS softens lattice distortions around a polaron, resulting in a reduction of the activation barrier. The extra volume introduced by tensile strain also reduces the barrier of Li+ ion migration.

• 出版日期2012-7-16