Tailoring electronic-ionic local environment for solid-state Li-O ₂ battery by engineering crystal structure

Abstract

Solid-state Li-O 2 batteries (SSLOBs) have attracted considerable attention because of their high energy density and superior safety. However, their sluggish kinetics have severely impeded their practical application. Despite efforts to design highly efficient catalysts, efficient oxygen reaction evolution at gas-solid interfaces and fast transport pathways in solid-state electrodes remain challenging. Here, we develop a dual electronic-ionic microenvironment to substantially enhance oxygen electrolysis in solid-state batteries. By designing a lithium-decorative catalyst with an engineering crystal structure, the coordinatively unsaturated sites and high concentration of defects alleviate the limitations of electronic-ionic transport in solid interfaces and create a balanced gas-solid microenvironment for solid-state oxygen electrolysis. This strategy facilitates oxygen reduction reaction, mediates the transport of reaction species, and promotes the decomposition of the discharge products, contributing to a high specific capacity with a stable cycling life. Our work provides previously unknown insight into structure-property relationships in solid-state electrolysis for SSLOBs.

Solid‐state Li–air batteries: Fundamentals, challenges, and strategies

“…(I) Comparison of the discharge capacity and overpotential of the solid‐state LOB with A–Li–RuO 2 with some previously reported systems. Reproduced with permission: Copyright 2022, AAAS 105 …”

“…The carbon-free ceramic cathode built up on both electronically and ionically conductive Ru-based composite, and LiOH-based reaction chemistry triggered by the addition of water vapor (Figure 4G,H), rendered remarkable promotion of specific capacity and battery stability of 200 mAh/g over 665 discharge-charge cycles, while other reported cathodes achieved only ∼50 mAh/g and ∼100 cycles. 104 Sun et al 105 realized the dual modulation of electronic and ionic microenvironment on a novel Li-decorated RuO 2 (Li-RuO 2 ) cathode with an amorphous structure, creating plenty of open frameworks with unsaturated sites and defects for promoting electronic-ionic transport, which benefited fast kinetics at the gas-solid interface for solid-state oxygen electrolysis (Figure 5G) and homogeneous distribution of discharge products on the cathode (Figure 5A-F). The assembled LOB with A-Li-RuO 2 exhibits a high specific capacity of 15,219 mAh/g at 100 mA/g and low polarization overpotential between discharge and charge (1.2 V), far superior to these values for C-Li-RuO 2 (11,900 mAh/g, 1.4 V) and rutile RuO 2 (7896 mAh/g, 1.6 V) (Figure 5H), as well as most reported solid-state LOBs (Figure 5I).…”

Field‐assisted electrocatalysts spark sulfur redox kinetics: From fundamentals to applications

“…Generally, electrochemical kinetics depend on the nature of the electrocatalysts and the localized concentration of the reactants at the electrocatalytic interface. [ 23 ] The simplified kinetic equation can be described as follows: $$$r=A\text{exp}\left(\frac{-{E}_{{\rm{a}}}}{{k}_{{\rm{B}}}T}\right){C}_{\mathrm{LiPSs}}{<mpadded xmlns="http://www.w3.org/1998/Math/MathML">C</mpadded>}_{\mathrm{Li}}^{2}\text{exp}\left(-\frac{\alpha e\eta }{{k}_{{\rm{B}}}T}\right),$$$where r is the reaction rate, A is the pre‐exponential factor, E a is the activation energy, $${k}_{B}$$ is the Boltzmann constant, T is the temperature, C LiPSs and C Li correspond to the respective concentration, α is the transfer coefficient, e is the elementary charge, and η is the overpotential. The introduction of fields shows a prominent effect on manipulating interfacial ion/electron motion and intrinsic geometrical‐site‐dependent reactivity.…”

“…Generally, electrochemical kinetics depend on the nature of the electrocatalysts and the localized concentration of the reactants at the electrocatalytic interface. [23] The simplified kinetic equation can be described as follows:…”

Maintaining Interfacial Transports for Sulfide-Based All-Solid-State Batteries Operating at Low External Pressure

“…Synchrotron X-ray computed tomography with sufficient compositional sensitivity was utilized to analyze and quantify the distribution of different components in the composite cathodes. − The visual image (the 3D volume rendering) of the composite cathode was rendered based on the X-ray attenuation of various components (Figure A,B). The segmented images of 104 × 162.5 × 52 μm of the cycled composite cathodes show the distribution and volume fraction of the three components: NCM network (high attenuation), SSE network (low attenuation), and voids (zero attenuation).…”