Zulueta Yohandys A, Nguyen Minh Tho, Dawson James A
Departamento de Física, Facultad de Ciencias Naturales y Exactas, Universidad de Oriente, Santiago de Cuba CP-90500, Cuba.
Computational Chemistry Research Group and Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam.
Inorg Chem. 2020 Aug 17;59(16):11841-11846. doi: 10.1021/acs.inorgchem.0c01923. Epub 2020 Aug 4.
Lithium stannate (LiSnO) is currently being considered as a material for electrode and electrode coating applications in Li-ion batteries. The intrinsic defect formation and Li-ion transport properties of LiSnO doped with divalent and trivalent transition-metal dopants (Mn, Fe, Co, and Ni) are explored in this work using atomistic simulations. Defect formation simulations reveal that all divalent dopants occupy the Li site with charge compensation through Li vacancies. For trivalent doping, occupation of the Sn site is energetically preferred with charge compensation from Li interstitials. Molecular dynamics simulations reveal that divalent and trivalent dopants increase Li-ion diffusion and reduce its activation energy compared with the undoped system. We show that LiSnO with Li excess or deficiency as a result of doping has improved Li-transport properties. This study highlights the substantial improvement in Li-ion diffusion of LiSnO for both current commercial and next-generation Li-ion battery technologies that can be achieved through transition-metal doping.
锡酸锂(LiSnO)目前被视为一种用于锂离子电池电极及电极涂层应用的材料。本工作采用原子模拟方法,探究了掺杂二价和三价过渡金属(锰、铁、钴和镍)的LiSnO的本征缺陷形成及锂离子传输特性。缺陷形成模拟表明,所有二价掺杂剂通过锂空位占据锂位点以实现电荷补偿。对于三价掺杂,占据锡位点在能量上更有利,由锂间隙原子进行电荷补偿。分子动力学模拟表明,与未掺杂体系相比,二价和三价掺杂剂提高了锂离子扩散速率并降低了其活化能。我们表明,由于掺杂导致锂过量或不足的LiSnO具有改善的锂传输特性。这项研究突出了通过过渡金属掺杂可实现的当前商用和下一代锂离子电池技术中LiSnO锂离子扩散的显著改善。