Fast-charging In Alkali-Ion Batteries: The impact of Interactions and Geometry on Reversibility and Diffusional limitations

E. LEIVA; M.GAVILAN; D. BARRACO

Congreso; 73 th ISE; 2022

International Society of Electrochemistry

A challenge for the lithium automotive industry is to produce fast-charging batteries to improve the performance of electric vehicles that currently present a relatively poor performance (270 km with a charging time of 6-7 hs). From the research perspective at a single particle level, three different processes mainly rule the charging speed: diffusion of ions inside electrodes, charge transfer at the electrode/electrolyte interface, and transport of ions through the electrolyte. To reveal how these phenomena, determine loading time bottlenecks we constructed with voltammetric simulations maps of reversibility and diffusional limitations called zone diagrams. A zone diagram is a useful way to identify different regions where mass transfer, charge transfer, particle size, and sweep rate of a voltammetric experiment determine the behavior of the system under consideration. Charge transfer can be classified as reversible (R), quasi-reversible (QR), and irreversible (I); concerning finiteness of diffusion, the behavior of the system is classified into surface waves (S), finite diffusion (F), and semi-infinite diffusion (SI). We are interested in unveiling, through general and simple models like Langmuir and Frumkin intercalation isotherms, the impact of interactions between the inserted ions and the geometry of the particle on this kind of map. Figures (a) and (b) show that the reversible zone and the quasi-reversible zone close to it are more sensitive to interactions (g=0 Langmuir, g>0 repulsive, g