Enabling Stable Lithium Metal Anode via 3D Inorganic Skeleton with Superlithiophilic Interphase

Abstract

of lithium metal batteries (LMBs). [3][4][5] Compared with intercalation compounds such as graphite in LIBs, lithium metal anode possesses an extremely high theoretical capacity of 3860 mA h g −1 with a very low redox potential (−3.04 V vs the standard hydrogen electrode), making it an attractive anode material to pair with highenergy conversion cathodes such as sulfur and oxygen. [6,7] Unfortunately, the application of lithium metal is full of challenges that have puzzled researchers for more than 40 years. [8] The most notorious one is that Li metal problematically forms dendrites during repeated cycling. [9] Owing to the multi-component solid electrolyte interphase (SEI) layer and uneven anode substrate, inhomogeneous lithium-ion flux is formed at the electrode/electrolyte interface, leading to nonuniform lithium eletrodeposition on the metal surface. The fresh metallic tip acts as an active site, which induces the ramified growth of lithium dendrite, resulting in cell short-circuit and low coulombic efficiency. This dendrite formation behavior can be much severe at high current densities. Another serious problem lies in electrode volume expansion originated from the repeated plating/ stripping process. [10,11] As a "hostless" electrode, lithium metal tends to be fully stripped when used in practical full cells and can hardly travel back to the same location during plating, causing mechanical instability of electrode/separator interface as well as internal stress fluctuation. As a result, the capacity of LMBs fades sharply during cycling.Over the past four decades, many up-and-coming strategies have been developed to enhance the electrochemical performance of Li metal anode and overcome the problems raised from uneven Li electrodeposition. These methods include doping electrolyte additives (Li halide, [12] ionic liquid, [13] and Cs +[14] ) and coating artificial SEIs (Li 3 PO 4 , [15] Cu 3 N, [16] LiF, [17] and Li alloy [18][19][20] ) on Li anode. More recently, researchers have focused on creating 3D scaffold/lithium metal composites as alternatives for common planar lithium. According to Chazalviel's model, the onset time of uneven deposition is inversely proportional to the current density (τ ≈ -2 J ). [21,22] Therefore, designing high-surface-area composite anode can lower J and thus prolong the cell lifetime. Based on this theory, Cu mesh, [23,24] Ni foam, [25] and other 3D conductive frameworks [26][27][28] have been developed to replace planar current The lithium metal battery (LMB) is among the most sought-after battery chemistries for high-energy storage devices. However, LMBs usually undergo uncontrollable lithium deposition and severe side reactions, which significantly impede their practical applications. Herein, a stable Al 2 O 3 -based inorganic framework with superlithiophilic lithium aluminum oxide (Li-Al-O) interphase is created via reacting Li with Al 2 O 3 nanoparticles. The Al 2 O 3 -based inorganic framework can serve as a stable Li "host," reducing the volume expansion during cell cyclin...

3D Porous Cu Current Collectors Derived by Hydrogen Bubble Dynamic Template for Enhanced Li Metal Anode Performance

“…Most importantly, the depositing high capacity weaken the SEI layer and produce cracks in the interface, allowing the side reaction between Li metal and liquid electrolyte, thus consuming additional electrolyte . Another method, using stable and effective host for storing Li, such as layered Li‐rGO composite film, 3D nickel foam, and vapor grown carbon fiber (VGCF) 3D conducting host, Janus gold nanoparticle‐modified carbon paper, 3D Al 2 O 3 ‐based inorganic skeleton, successfully confines Li in the host materials, relieves the volume change, and induces uniform Li plating. As a key component of the Li anode, numerous 3D porous forms of Cu current collectors with high surface area have been used to accommodate the deposited Li metal and prevent dendrite growth, such as 3D Cu foil with submicrometer skeleton, 3D Cu skeleton with open micrometer‐sized pores, free‐standing Cu nanowire network, electrochemical and chemical dealloying derived 3D porous Cu substrate, and lithiophilic Cu‐CuO‐Ni hybrid structure .…”

Boosting the Reversibility of Sodium Metal Anode via Heteroatom‐Doped Hollow Carbon Fibers

“…In spite of its infancy stage in research, progresses on Na‐S, Na‐O 2 , and Na‐CO 2 batteries using Na metal anode have been continuously reported with great potential . However, the practical usage of Na metal anode is still challenging, especially in conventional organic liquid electrolytes . On the one hand, the propensity of irregular ion nucleation on Na metal induces mossy, dendritic Na growth and accelerates the formation of “dead‐sodium.” On the other hand, the hyper‐reactivity of Na metal contributes to thick, porous solid electrolyte interface (SEI) .…”

Facile Generation of Polymer–Alloy Hybrid Layers for Dendrite‐Free Lithium‐Metal Anodes with Improved Moisture Stability

“…[1] Unfortunately,L MAs suffer from anumber of challenges,including continuous side reactions,u ncontrolled growth of lithium dendrites,a nd infinite volume changes during cycling, [2] which result in low Coulombic efficiency (CE), fast capacity fading,short circuiting, and even fire breakout. [3] Recently,m any strategies have been developed for tackling these problems,s uch as creating three-dimensional (3D) structure current collectors for uniform lithium deposition and less volume expansion, [4,5] selecting suitable electrolyte additives for the in situ formation of protective films, [6,7] employing gel-polymer/solid-state electrolytes to suppress Li dendrites,a nd constructing artificial solid electrolyte interphase (SEI) layers to prevent side reactions. [8][9][10][11] Among these approaches,b uilding lithiophilic alloy interfacial layers has been certified as an effective method for the homogeneous deposition of lithium, since the alloy layer can provide fast lithium-ion transportation channels.…”