Expansion-Tolerant Lithium Anode with Built-In LiF-Rich Interface for Stable 400 Wh kg^–1 Lithium Metal Pouch Cells

Abstract

Lithium metal anodes hold great promise for enabling high-energy density devices compared with the commercialized graphite electrode. However, huge pressure changes during cycling will lead to the pulverization of the 2D lithium anode, thus deteriorating the battery life due to its poor mechanical strength. Herein we report a 3D lithium−boron (LiB) fibrous framework with great compressive strength through electrochemical delithiation. The LiB alloy fibers with a 3D stable structure play the role of an expansion-tolerant substrate, which could effectively hold the Li metal and reduce the internal pressure changes, showing only a 53.7% pressure change compared with the 2D Li/Cuanode-based pouch cell. A quasi-ionic-liquid-based polymer electrolyte layer is introduced by a scalable tape-casting method, generating a LiF-rich layer inside the 3D Li anode through the reaction between the polymer electrolyte and the internal free Li, which can guide the uniform nucleation and growth of Li metal. As a result, the asymmetric Li−Li cell can sustain 5 mAh cm −2 Li plating/ stripping for 1000 h. A 2.1 Ah pouch cell coupling to a LiF-rich interface-protected 3D Li/LiB anode and a Ni-rich cathode of 30 mg cm −2 exhibits an ultrahigh energy density of 403 Wh kg −1 and a stable cycle life of 100 cycles.

Chloride Ion‐Containing Polymeric Ionic Liquids for Application as Electrolytes in Solid‐State Batteries

“…Many examples of such PELs used in lithium ion batteries have already been described. [29][30][31][32] The suitability of this concept for organic batteries has recently also been demonstrated for organic solid-state batteries. These electrolytes were based on benzyl(meth)acrylates, poly(ethylene glycol) (PEG) monomethylether and PEG methyletheracrylate, cross-linker and the IL 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (EMImTFSI) as swelling agent and conducting salt.…”

Stabilizing the Li1.4Al0.4Ti1.6(PO4)3/Li interface with an in situ constructed multifunctional interlayer for high energy density batteries

“…2 Solid-state lithium batteries (SSLBs) with solid-state electrolytes are attractive alternatives to conventional lithium batteries. [3][4][5][6][7][8][9] Among various solid-state electrolytes, Li 1.0+x Al x -Ti 2−x (PO 4 ) 3 (LATP), a sodium super-ionic conductors (NASICON)-type solid-state electrolyte, is a promising one with high ionic conductivity (∼10 −3 S cm −1 ), wide electrochemical windows (2.16 V-4.31 V) and low cost. 10,11 Unfortunately, serious interfacial side reactions of LATP impede its application in Li metal batteries.…”

Anionic Activity in Fast-Charging Batteries: Recent Advances, Prospects, and Challenges

“…In terms of Li + transport, compared with organic-rich SEI, the construction of SEI with a predominance of inorganics allows for a reduced energy barrier for interfacial Li + transport (Figure f), which includes the facile Li + desolvation and rapid Li + diffusion kinetics across SEI. ,− The construction of anion-derived SEI with enhanced interfacial ion transport shows great potential for fast-charging applications.…”