Boosting the Optimization of Lithium Metal Batteries by Molecular Dynamics Simulations: A Perspective

Abstract

the capacity of batteries; 3) large volume changes during circulation process can tend to bring about the fragmentation of solid electrolyte interphase (SEI), exposing the fresh lithium metal inside that the electrolyte will continue to react with lithium metal to consume the electrolyte and the growth of dendrite cannot be effectively inhibited (Figure 1). [3-6] Several ways have been put forward to solve these problems, [7-9] but the proposed methods to improve the performance of LMBs still face several influence factors: 1) the solvation sheath of Li + in liquid electrolyte and the ion conductivity in both gel and solid electrolyte; 2) the formation and components of solid electrolyte interfaces (SEI); (3) the deposition behavior of Li + on the surface of anode. A detailed microscopic understanding of island growth mechanism is required to successful solve these problems. Recently, some advanced characterization methods (scanning electron microscope, cryo-transmission electron microscope and lots of in situ characterization technology such as in situ X-ray diffraction, in situ fourier transform infrared spectroscopy, in situ UV absorption spectroscopy [10-12]) and advanced electrochemical measurement (cyclic voltammetry, impedance test, magnification test, exchange current density, and polarization test [13-16]) have been employed to figure out the dynamic behavior of different models. However, these characterizations and measurements are only focused on the description of test results in the level of phenomenon, lack of rational explanation. Many applications still need physical theoretical analysis to comprehend their kinetics mechanism, where molecular dynamics simulation can be used to strengthen the insights into the mechanism investigation of LMBs. [17] With the development of computational simulation technique such as Density Functional Theory (DFT) and Finite element simulation, molecular dynamics (MD) is one of the most frequently-used computational simulations in many fields. It is a science of simulating the motions of particles in system which combines with physics, mathematics and chemistry. Therefore, it can help researchers understand properties of assemblies of molecules by calculating the forces under different interaction potentials. Generally speaking, MD simulate can be divided into classic molecular dynamics (CMD) under Newtonian equation, reactive molecular dynamics (RMD) under reaction force field, ab initio molecular dynamics (AIMD) under Schrodinger The Li metal battery is attracting more and more attention in the field of electric vehicles because of its high theoretical capacity and low electrochemical potential. But its inherent disadvantages including uncontrolled lithium dendrites, high chemical activity, and large volume changes hold back the large-scale application of stable Li metal anodes. Recently, various computational studies have been used to facilitate the rationalization of experimental observed phenomenon. In this review, the progress of molecular dynamics simulations i...

Confronting the Challenges in Lithium Anodes for Lithium Metal Batteries

“…The simulation and calculation can strengthen the insight into the deposition of lithium, the diffusion and the solvation chemistry of Li + . [ 166 , 167 ] Understanding the deposition behavior of lithium is essential for improving the performance. Based on the phase field model, the deposition rate of lithium in the conductive 3D host was revealed.…”

Ionic Liquid@Metal-Organic Framework as a Solid Electrolyte in a Lithium-Ion Battery: Current Performance and Perspective at Molecular Level

“…Compared to the quantum mechanical approach, which treats electrons of each atom in the calculation, in classical mechanics, each atom is simulated as a single particle. Whichever method is used, the main objective of computational modelling is to simulate the atomistic behavior of materials by using correct algorithms and approximations [ 116 , 117 , 118 ].…”

Self‐Healing Mechanism of Lithium in Lithium Metal

“…[ 8 , 9 ] Although researchers have generally agreed on the atomic‐scale behavior of Li‐dendrite growth, most experimental studies have only described this phenomenon, without providing a comprehensive understanding. [ 10 , 11 ] For instance, the critical current density (CCD) is commonly used to determine whether dendritic growth will occur; [ 12 , 13 ] in other words, it is considered that Li dendrites will only grow above the CCD. However, there is evidence that Li can repair itself and inhibit dendrite formation when the current density is sufficiently high.…”