Impacts of the Conductive Networks on Solid-State Battery Operation

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• Composite cathode micromorphology significantly impacts all-solid-state battery (ASSB) performance.
• Current understanding relies on empirical data, lacking mechanistic depth.
• Charge neutrality in battery chemistry necessitates analysis of conductive networks.

Purpose of the Study:

• To systematically investigate the microscopic electrochemical effects of conductive network micromorphology in ASSB cathodes.
• To understand the impact of varying Li+ to e- channel ratios on cathode performance and degradation.
• To provide mechanistic insights for rational design of future solid-state battery cathodes.

Main Methods:

• Utilized multiscale synchrotron-based spectro-microscopy to analyze cathode micromorphology.
• Employed X-ray nano-tomography on a model system to resolve electron (e-) and lithium-ion (Li+) channels.
• Conducted electrode-scale X-ray holotomography to assess particle-size dependency.

Main Results:

• Unbalanced Li+ and e- conducting channels lead to intensified charge polarization and accelerated degradation of active cathode materials.
• Spatially uniform and well-paired Li+ and e- channels promote uniform lithiation/delithiation, reducing polarization.
• The influence of conductive networks on battery performance is particle-size dependent, with smaller particles being more sensitive.

Conclusions:

• Micromorphology of conductive networks critically influences ASSB cathode performance.
• Balanced ion and electron transport pathways are essential for mitigating polarization and enhancing battery stability.
• These findings offer a foundation for designing optimized cathode architectures for advanced solid-state batteries.