Article

• Next-generation lithium metal batteries and LiCoO₂ cathodes offer high performance potential but face critical challenges like unstable interfaces and material degradation. 

• Engineered particles (Ep) are being explored to stabilize electrode interfaces and improve SEI formation, though their complex structures require advanced analysis. 

• TOF-SIMS enables high-resolution chemical mapping and depth profiling to uncover degradation pathways and electrolyte breakdown products. 

• XPS complements TOF-SIMS by providing precise chemical state data across thin films and layered battery materials. 

• The combined use of TOF-SIMS and XPS delivers a powerful, multi-dimensional view of battery interfaces—essential for improving safety, charge speed, and longevity. 

As the demand for high-performance energy storage intensifies, lithium metal batteries and high-energy-density cathodes such as lithium cobalt oxide (LCO) are emerging as promising candidates. Yet their commercial viability hinges on overcoming persistent challenges such as unstable electrode-electrolyte interphases, lithium dendrite growth, and electrolyte-induced degradation. Engineered particles (Ep) offer a compelling solution by stabilizing electrode interfaces and enhancing SEI formation, but their complex architectures pose significant analytical hurdles. 

This presentation highlights how advanced surface analysis techniques, specifically time-of-flight secondary ion mass spectrometry (TOF-SIMS) and X-ray photoelectron spectroscopy (XPS), can unravel the chemical intricacies of Ep-treated electrodes. By combining multi-technique XPS capabilities and high-resolution TOF-SIMS, we can gain a comprehensive view of both surfaces and buried interfaces. TOF-SIMS excels in detecting both organic and inorganic species with exceptional spatial resolution, allowing precise chemical mapping across the structure of the cathodes, and its depth profiling capabilities can reveal the distribution of electrolyte breakdown products and metal migration pathways, which provide critical insights for understanding degradation mechanisms. In parallel, XPS provides quantitative chemical state information across thin films and layered structures, enabling precise characterization of interfacial stability.