Lithium-ion Battery Chemistry

Solid state metal-sulfur batteries  have long suffered from poor performance due to the low reactivities of both elemental sulfur (S) and lithium sulfide (Li2S). To address these challenges, we have been exploring doping S and Li2S with halides and/or transition metals to enhance their ionic and electronic conductivity, alter reaction pathways, minimize volume changes, and even enable thermal annealing to reverse degradation.

This presentation highlights advances in molecular, liquid-state, and solid-state electrolytes for high-voltage lithium batteries operating across a wide temperature range, including low-temperature conditions. Key strategies include controlling ion solvation, engineering stable electrode–electrolyte interphases, and suppressing dendrite formation in lithium metal cells. Recent examples featuring dinitrile-, sulfone-, and ether-based electrolytes demonstrate improved safety, stability, ionic transport, and performance for next-generation high-voltage cathodes and lithium metal anodes.

Electrode performance is dependent on multiscale factors that modify ion and charge transport during cycling. Cross-sectioning of intact coin cells and electrodes with cryogenic electron microscopy workflows can identify cathode particle microstructure, degradation, and the formation of cathode–electrolyte interphases that can change the local charge transport pathways and lead to increased Li-ion transfer impedance. Our automation of these multiscale workflows is enabling rapid evaluation and feedback on battery design.

Lithium-ion battery growth is commonly viewed through cathode materials, yet every cell relies on graphite anodes. This presentation explores how battery-grade graphite production depends on petroleum coke, a refinery by-product with limited and competing end uses. Covering regional supply-demand dynamics, synthetic and natural graphite pathways, emerging anode technologies, and carbon intensity, the session highlights why petcoke availability may become a critical determinant of future battery supply chains.

Lithium-rich, manganese rich (LMR) cathode materials have attributes that can result in highly advantaged lithium-ion cells, and this class of materials requires sometimes unexpected design attributes to achieve optimal performance. This talk explores how an advanced LMR CAM, LXMO produced by Stratus Materials, can be implemented in high-performance cells that allow for cells to be produced with the cost and safety of LFP along with NMC energy densities.

High-mass-loading cathodes are essential for achieving practical energy densities in all-solid-state batteries (ASSBs). However, their capacity utilization and rate capability are often limited by high tortuosity and sluggish lithium-ion transport through thick cathode architectures. In this work, we investigate lithium-ion transport limitations in high-loading ASSB cathodes using laser-induced breakdown spectroscopy (LIBS), which probes lithium distribution and transport behavior and shows clear evidence of nonuniform lithiation across the cathode thickness. We will present LIBS measurements on several different ASSB cathode thicknesses and discuss potential strategies to mitigate these transport limitations.