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Title: Kinetics or Transport: Whither Goes the Solid-State Battery Cathode?
Solid-state batteries (SSBs) hold the potential to enhance the energy density, power density, and safety of conventional lithium-ion batteries. The theoretical promise of SSBs is predicated on the mechanistic design and comprehensive analysis of various solid–solid interfaces and microstructural features within the system. The spatial arrangement and composition of constituent phases (e.g., active material, solid electrolyte, binder) in the solid-state cathode dictate critical characteristics such as solid–solid point contacts or singularities within the microstructure and percolation pathways for ionic/electronic transport. In this work, we present a comprehensive mesoscale discourse to interrogate the underlying microstructure-coupled kinetic-transport interplay and concomitant modes of resistances that evolve during electrochemical operation of SSBs. Based on a hierarchical physics-based analysis, the mechanistic implications of solid–solid point contact distribution and intrinsic transport pathways on the kinetic heterogeneity is established. Toward designing high-energy-density SSB systems, the fundamental correlation between active material loading, electrode thickness and electrochemical response has been delineated. We examine the paradigm of carbon-binder free cathodes and identify design criteria that can facilitate enhanced performance with such electrode configurations. A mechanistic design map highlighting the dichotomy in kinetic and ionic/electronic transport limitations that manifest at various SSB cathode microstructural regimes is established.
Authors:
; ;
Award ID(s):
2041499
Publication Date:
NSF-PAR ID:
10336716
Journal Name:
ACS Applied Materials & Interfaces
ISSN:
1944-8244
Sponsoring Org:
National Science Foundation
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Such modeling and analysis help to elucidate the fundamental mechanisms that govern cathode performance and degradation in Li-S batteries. The current study also provides design strategies for the sulfur cathode as well as selection approaches to novel battery systems. References: Bhargav, A., (2020). Lithium-Sulfur Batteries: Attaining the Critical Metrics. Joule 4 , 285-291. Chung, S.-H., (2018). Progress on the Critical Parameters for Lithium–Sulfur Batteries to be Practically Viable. Advanced Functional Materials 28 , 1801188. Peng, H.-J.,(2017). Review on High-Loading and High-Energy Lithium–Sulfur Batteries. Advanced Energy Materials 7 , 1700260. Chu, T., (2021). 3D printing‐enabled advanced electrode architecture design. Carbon Energy 3 , 424-439. Shi, Z., (2021). Defect Engineering for Expediting Li–S Chemistry: Strategies, Mechanisms, and Perspectives. Advanced Energy Materials 11 . Figure 1« less
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