In-silico design of Li-ion batteries
Li-ion rechargeable batteries are promising candidates as portable and durable energy sources, due to their high energy density and power density. In spite of Li-ion batteries (LIB) being the leading battery technology today, there is much room for improvement. Indeed, there are challenges to overcome, such as capacity fading and stability in LIB. In our group, we investigate basic properties, such as electronic, magnetic, mechanical, and electrochemical properties of different cathode materials. Understanding these properties will advance our ability to design novel materials for LIB. The cathode materials being studied include layered oxides, spinel oxides, olivine phosphates, and more. To study these cathodes, we use density functional theory (DFT), as well as a range of classical simulation techniques.
Li-based Ni, Co, and Mn (NCM) layered cathode materials are leading contenders for automotive applications. Recently, we have studied a range of NCM layered cathode materials using a combination of DFT and classical atomistic simulation methods. Using these methods, we are able to predict both the correct atomic structure as well as a multitude of properties relevant to electrochemistry. We also have investigated the effects of doping on electrochemical, thermodynamic and kinetic properties of NCM materials. We have shown that stability and capacity can be increased with high valent dopants, such as Zirconium (Zr) or Aluminum (Al).
Our group is also engaged in studies of geometry, electronic structure, electrochemical potential and magnetism in olivine phosphate type cathode materials for Li-ion rechargeable batteries. We have addressed questions such as the significant role of spin-orbit coupling, effect of doping on cell voltages and structure and more. For a long time, the question of whether Li ions possess some quantum mechanical delocalized nature during diffusion, has remained unanswered. We have performed classical and quantum modelling of Li and Na diffusion in olivine and layer based cathode materials, and have found that Li indeed has a quantum delocalized nature during diffusion.
See also www.inrep.org.il.
The Simulations Tools:
We study the LIB systems using plane wave based DFT tools. We study bulk properties using tools such as geometry optimization, nudged elastic bands, molecular dynamics, and more. The primary software tools are VASP, GULP, Gaussian, and more.