Kinetics Tuning the Electrochemistry of Lithium Dendrites Formation in Lithium Batteries through Electrolytes

Abstract

Lithium batteries are one of the most advance energy storage devices in the world and have attracted extensive research interests. However, lithium dendrite growth was a safety issue which handicapped the application of pure lithium metal in the negative electrode. In this investigation, two solvents, propylene carbonate (PC) and 2-methyl-tetrahydrofuran (2MeTHF), and four Li salts, LiPF, LiAsF, LiBF and LiClO were investigated in terms of their effects on the kinetics of lithium dendrite formation in eight electrolyte solutions. The kinetic parameters of charge transfer step (exchange current density, j, transfer coefficient, α) of Li/Li redox system, the mass transfer parameters of Li (transfer number of Li, t, diffusion coefficient of Li, D), and the conductivity (κ) of each electrolyte were studied separately. The results demonstrate that the solvents play a critical role in the measured j, t, D, and κ of the electrolyte, while the choice of Li salts only slightly affect the measured parameters. The understanding of the kinetics will gain insight into the mechanism of lithium dendrite formation and provide guidelines to the future application of lithium metal.

Nonflammable quasi-solid-state electrolyte for stable lithium-metal batteries

“…12 Lithium metal anode tends to form unstable solid electrolyte interface (SEI) layer with typical carbonate electrolytes, which leads to lithium dendrite and dead lithium, resulting in capacity fade and safety problems (i.e., combustion, leakage and explosion). [13][14][15][16][17][18] Also, cathodes charged to high potential can oxidize carbonate electrolytes, and introduce many harmful byproducts at the interface. 19,20 To replace organic electrolytes, solid-state electrolytes (SSEs) have been introduced and investigated considerably to tackle these problems.…”

Advances of Carbon-Based Materials for Lithium Metal Anodes

“…The liquid electrolyte is composed of solvent, lithium salt and additives, which determine the uniformity and stability of SEI film. Therefore, modifying the additives can improve the performance of the electrolyte, then changing the deposition morphology of lithium (Tao et al, 2017;Wang et al, 2020).…”

Progress and Perspective of Constructing Solid Electrolyte Interphase on Stable Lithium Metal Anode

“…The ideal SEI should have high ionic conductivity, near-insulated electronic conductivity, proper thickness, dense structure and high elastic modulus to suppress dendrite penetration. The application of additives in electrolyte is one of the most facile ways to improve the stability of the SEI because it can directly affect the physical and chemical properties of the SEI, change the interface environment and finally improve the lithium deposition behavior (Tao et al, 2017). Additives can be divided into two types which are film-forming additives and Li + plating additives according to the formation mechanism of SEI.…”