Brushed Metals for Rechargeable Metal Batteries

Abstract

Battery designs are swiftly changing from metal‐ion to rechargeable metal batteries. Theoretically, metals can deliver maximum anode capacity and enable cells with improved energy density. In practice, these advantages are only possible if the parasitic surface reactions associated with metal anodes are controlled. These undesirable surface reactions are responsible for many troublesome issues, like dendrite formation and accelerated consumption of active materials, which leads to anodes with low cycle life or even battery runaway. Here, a facile and solvent‐free brushing method is reported to convert powders into films atop Li and Na metal foils. Benefiting from the reactivity of Li metal with these powder films, surface energy can be effectively tuned, thereby preventing parasitic reaction. In‐operando study of P2S5‐modified Li anodes in liquid electrolyte cells reveals a smoother electrode contour and more uniform metal electrodeposition and dissolution behavior. The P2S5‐modified Li anodes sustain ultralow polarization in symmetric cell for >4000 h, ≈8× longer than bare Li anodes. The capacity retention is ≈70% higher when P2S5‐modified Li anodes are paired with a practical LiFePO4 cathode (≈3.2 mAh cm−2) after 340 cycles. Brush coating opens a promising avenue to fabricate large‐scale artificial solid‐electrolyte‐interphase directly on metals without the need for organic solvent.

Flash Recycling of Graphite Anodes

“…These initial charge specific capacities are slightly lower than the theoretical value of graphite (≈372 mAh g −1 ), but they can be improved by the design of cycling protocols and the formation cycles (Note S4, Supporting Information). [ 51 ] The surface areas and pore size distributions of various anode materials are determined by N 2 adsorption/desorption curves as shown in Figures S27–S28, and Table S4, Supporting Information. The surface area of untreated anode waste is 9.0 m 2 g −1 , which is larger than the commercial graphite with surface area of ≈4.0 m 2 g −1 used in the work.…”

Battery metal recycling by flash Joule heating

“…The repeated electrochemical cycling in LIBs incurs the accumulation of a compact SEI layer (32)(33)(34). XPS analyses show that the layer includes various organic and inorganic salts that precipitate as surface films on the electrodes (Fig.…”

Green mechanochemical Li foil surface reconstruction toward long-life Li–metal pouch cells

“…Recently, researchers have proposed a solvent-free, dry coating method that can effectively destroy the surface passivation layer on Li foil, while nano-powder in situ lithiated on the Li foil surface forms a functional layer, which is a promising surface-modification strategy that can promote the commercialization of Li metal batteries. 11,20 Fumed silica has been found to have good affinity for Li + and low cost. As an electrolyte additive, it can homogenize the Li + flow and achieve good electrochemical performance for Li metal batteries.…”