The Interface between Li6.5La3Zr1.5Ta0.5O12 and Liquid Electrolyte

Abstract

An advantageous solid electrolyte/liquid electrolyte interface is crucial for the implementation of a protected lithium anode in liquid electrolyte cells. Li 6.5 La 3 Zr 1.5 Ta 0.5 O 12 (LLZTO) garnet electrolytes are among the few solid electrolytes that are stable in contact with lithium metal. We show LLZTO is unstable in contact with the organic carbonate-based Li + liquid electrolyte used in conventional Li-ion cells. The interfacial resistance between LLZTO and LiPF 6 in (CH 2 O) 2 CO: OC(OCH 3 ) 2 (1:1 v/v) increases with time due to the growth of a lithium-ion-conducting solid electrolyte interphase (SEI) at the surface of the ceramic electrolyte. The interphase is composed of Li 2 CO 3 , LiF, Li 2 O, and organic carbonates. Even at a rate of 5 mA cm À2 , a 3 V potential drop occurs across the LLZTO/liquid electrolyte interface. A practical LLZTO membrane (thickness $10 mm), in contact with a lithium anode, gives a potential loss of $16 mV, less than 1% of the resistance of the SEI.

From Liquid- to Solid-State Batteries: Ion Transfer Kinetics of Heteroionic Interfaces

“…The authors found a constant ohmic resistance attributed to ionic conduction in the SLEI as well as a term dependent on the salt concentration in the LE. Recently, the same system was analyzed by means of EIS, transmission electron microscopy (TEM), XPS, ToF-SIMS, and magic angle spinning nuclear magnetic resonance spectroscopy (MAS NMR) [51]. Decomposition of the SE and the LE resulted in the formation of an SLEI comprising LiF, Li 2 O , Li 2 CO 3 , and organic fragments.…”

“…Decomposition of the SE and the LE resulted in the formation of an SLEI comprising LiF, Li 2 O , Li 2 CO 3 , and organic fragments. The resistance of the SLEI thereby increased gradually until stablized after about 150 h [51].…”

“…Information on the origin of the interface resistances is scarce, and only limited chemical analysis of the interfaces is available. Only recently, a three-dimensional interphase has been reported, comprising decomposition products of the electrolytes [5,25,50,51].…”

Mg2+/F− Synergy to Enhance the Ionic Conductivity of Na3Zr2Si2PO12 Solid Electrolyte for Solid‐State Sodium Batteries

“…In order to further insight into the existence form of fluorine, F 1s in the surface and interior of NZSP‐0.10MF pellet were detected by high‐resolution XPS (Figure S2). The peak at ∼689 eV corresponds to F−Si/P bond, demonstrating the presence of F − occupying part of the O 2− site in NZSP lattice. Meanwhile, obvious differences in the intensities of F 1s peaks at ∼684 eV, which corresponds to negatively charged F − state, are observed in surface and interior.…”

Rhombohedral Li1+xYxZr2-x(PO4)3 Solid Electrolyte Prepared by Hot-Pressing for All-Solid-State Li-Metal Batteries

“…Compared with the sulfide ceramics, the oxide ceramics show a larger electrochemical window, a much better stability in air, and a much lower cost. Oxide garnet-type (e.g., Li 7 La 3 Zr 2 O 12 ) [14][15][16][17][18][19], NASICON-type (e.g., Li 1+x MxTi 2-x (PO 4 ) 3 , M = Al, Ge) [20][21][22][23][24][25][26], perovskite-type (e.g., Li 3x La( 2/3)−x (1/3)−2x TiO 3 ) [27][28][29][30][31], and antiperovskite-type electrolytes (e.g., Li 2 OHX, X = Cl, Br) [32][33][34][35][36][37][38] have been reported to have high Li-ion conductivities at room temperature because of the suitable Li-ion transport channel inside the framework. Garnet and antiperovskite electrolytes are reported to be unstable in moist air, and the reaction between them and moisture destroys the structure, reduces the Li-ion conductivity of the solid electrolyte, and significantly increases Li-ion resistance across the interface [39][40][41].…”