Researchers from the University of Limerick and Trinity College Dublin, led by Lukas Worch and Valeria Nicolosi, have made significant strides in understanding the degradation processes in lithium-ion batteries, particularly those using tin selenide (SnSe) as an anode material. Their work, published in the journal Nature Communications, offers critical insights that could lead to more durable and stable next-generation battery materials.
Lithium-ion batteries are a cornerstone of sustainable energy technologies, powering everything from electric vehicles to renewable energy storage systems. However, their long-term performance is often hindered by degradation processes that reduce capacity and efficiency over time. Tin selenide (SnSe) has emerged as a promising anode material due to its high theoretical capacity. Unlike conventional electrodes, SnSe undergoes conversion and alloying reactions with lithium, enabling high lithium storage but also causing large volume changes that lead to mechanical instability and capacity fading.
To mitigate these effects, researchers embedded SnSe nanoparticles within a Ti3C2Tx MXene framework, enhancing conductivity and structural resilience. Using advanced techniques like cryogenic focused ion beam (cryo FIB) slice and view, they observed progressive material redistribution and morphological transformation during battery cycling. This underscored the need for site-specific chemical analysis to understand degradation mechanisms better.
Cryogenic atom probe tomography (cryo APT) provided high spatial and chemical resolution while preserving beam-sensitive phases. This revealed nanoscale degradation mechanisms, including phase transformations, partial dissolution of active material, and crucially, the first direct evidence of copper corrosion and copper ion migration from the current collector into the electrode. The observation of copper redistribution demonstrates that current collector degradation contributes directly to chemical contamination and capacity fading in composite electrodes.
The combination of cryo FIB and cryo APT offers a powerful workflow for elucidating electrode degradation in reactive, beam-sensitive systems. This research provides critical insights for designing more durable and stable next-generation battery materials, which could significantly enhance the performance and longevity of energy storage systems.
For the energy sector, these findings are particularly relevant. By understanding and mitigating degradation processes, researchers can develop more robust battery materials that last longer and perform better. This could lead to more efficient energy storage solutions, reducing costs and improving the reliability of renewable energy systems. The practical applications include longer-lasting batteries for electric vehicles, more efficient grid storage solutions, and improved performance of portable electronic devices.
Source: Nature Communications
This article is based on research available at arXiv.