Current Status and Future Perspective on Lithium Metal Anode Production Methods

Abstract

Lithium metal batteries (LMBs) are one of the most promising energy storage technologies that would overcome the limitations of current Li‐ion batteries, based on their low density (0.534 g cm−3), low reduction potential (−3.04 V vs Standard Hydrogen Electrode) as well as their high theoretical capacities (3860 mAh g−1 and 2061 mAh cm−3). The overall cell mass and volume would be reduced while both gravimetric and volumetric energy densities would be greatly improved. Their electrochemical performance, however, is hampered by the low efficiency at high current densities and continuous degradation, which are related, among other factors, to the properties of the lithium metal anode (LMA). Hence, the production and processing of LMAs is crucial to obtain the desired properties that would enable LMBs. Here, the conventional method used for the production of LMAs, which is the combination of extraction, electrowinning, extrusion, and rolling processes, is reviewed. Then, the advances in the different alternative methods that can be used to produce and improve the properties of LMAs are described, which are divided into vapor phase, liquid phase, and electrodeposition. Within this last method, the anode‐less concept, for which different approaches to the development of advanced current collectors are illustrated, is included.

Evolution of the Interphase between Argyrodite-Based Solid Electrolytes and the Lithium Metal Anode─The Kinetics of Solid Electrolyte Interphase Growth

“…Commercially available lithium foils are usually treated to form a uniform passivation layer that prevents side reactions of the lithium with its environment. − As lithium hydroxide (LiOH) and lithium carbonate (Li 2 CO 3 ) form well-covering surface films, the passivation layer is mostly formed out of these compounds. In addition, the storage conditions (e.g., atmosphere in a dry room, glovebox, pouch container, etc.)…”

An Experimental Method to Determine the Measurement Error of Reference Electrodes within Lithium‐Ion Batteries

“…[1] The reasons for this are quickly identified, but complex in their origin: Elemental lithium is still the most used reference electrode (RE) in non-electrolytic, beaker-less, non-aqueous, sealed cells since it is easy to implement and requires no conversion (vs. Li/Li + ). [2][3][4][5] The issue with Li is that the measured potentials vitally depend on the electrolyte composition [6,7] and concentration [8] and its cleaning procedure, [9] limiting their comparability considerably. An equally constraining factor is the encountered variation of the design and size of REs, delivering different potentials even if the RE material is the same.…”

Understanding the Influence of Li7La3Zr2O12 Nanofibers on Critical Current Density and Coulombic Efficiency in Composite Polymer Electrolytes

“…An understudied metric in the solid-state battery field is Coulombic efficiency (CE), the amount of charge accessible in the discharge step following charging. Most CE reports focus on how the cathode efficiency behaves with a thick lithium anode. − However, the emergence of anode-free and low-excess lithium cell designs for high energy density applications makes CE at the anode a very important metric for long-life batteries. − The role of all relevant chemistries in the CPEspolymer, salt, and ceramicin determining CCD and CE needs to be addressed if CPEs are to remain relevant in solid-state lithium battery development.…”