Laser-induced breakdown spectroscopy (LIBS) can transform battery diagnostics and contaminated wood recycling, new studies suggest.
What if laser-based diagnostics were embedded in recycling centres, battery plants, and waste treatment facilities? A group of Portuguese researchers has published two high-impact studies showcasing innovative uses of Laser-Induced Breakdown Spectroscopy (LIBS) technology as a tool with significant applications in both the energy and waste management sectors.
Carried out by the Portuguese research and development (R&D) institution INESC TEC, the studies present two transformative applications of said technology: battery diagnostics and hazardous waste screening, positioning LIBS as a potential key actor in the transition to a more circular economy.
How does it work? Light holds the answers: LIBS is an elemental detection technique that enables real-time analysis and portability with minimal sample preparation. When performing this type of analysis, a high-energy density laser pulse focuses on the sample surface, vaporizing the material and heating it to extreme temperatures, creating plasma. After this disruption, plasma starts to cool down and emits light containing the characteristic wavelengths of the elements present in the sample.
The team applied this technique to perform post-mortem analysis of battery current collectors, allowing for detailed mapping of elemental composition. This technique offers a new, scalable way to monitor battery degradation and recycling potential — without the need for complex sample preparation or chemical processing.
And that’s crucial. With the increasing negative impacts of climate change and the continuous institutional push to achieve the goal of net-zero emissions by 2050, rechargeable batteries take the central stage in the transportation and energy sectors. Lithium-ion batteries are crucial to reducing dependence on fossil fuels. However, the battery supply chain relies heavily on finite natural resources such as lithium, cobalt and nickel. The extraction and refining of these materials comes with strings attached.
This is where advanced analytical technologies like LIBS come into play. All-Solid-State Batteries (ASSBs) can be a game changer; however, even minor impurities or deviations in the electrode layers or solid electrolyte can compromise the safety and performance of the cell. The study focused specifically on anode-less architectures - a particularly demanding configuration developed by a team of researchers of the Faculty of Engineering of the University of Porto.
"Our method provided direct visual evidence of lithium metal deposition and degradation patterns in next-generation battery architectures, enabling faster diagnostics with minimal environmental impact," said Diana Guimarães, lead author of the study published in Journal of Power Sources.
The findings can contribute to the development of more durable and sustainable batteries, in line with the goals of energy transition and electric mobility. “Understanding the spatial chemistry of battery failure is key to designing safer, longer-lasting devices and LIBS gives us a fast, scalable way to do that,” mentioned the INESC TEC researcher.
From batteries to waste
The same applies to hazardous waste. While the wood industry is often mentioned as a “good example” of adopting recycled materials, managing and reusing wood waste remains a challenging process due to the frequent presence of hazardous contaminants. This study presents a unique three-line LIBS screening method for several wood waste contaminants, offering a solution with visual output, representing a significant step forward compared to traditional approaches.
“Our team developed a simplified LIBS method that not only identifies hazardous elements in recycled wood, but also provides intuitive visual outputs - making it easier to integrate into real industrial processes and support faster, on-site decision-making”, stated Diana Guimarães.
Conventional detection techniques are limited by the need for extensive sample preparation and time-consuming and expensive analysis. “The recycled wood industry plays a crucial role in promoting sustainability and preserving resources within the wood products sector”, outlines the study. Nowadays, for instance, particleboard is produced using 50 % to 75 % recycled wood, reducing the demand for virgin wood and diverting valuable materials from landfills.
Unfortunately, this comes with a catch: the presence of hazardous elements that can pose serious risks to human safety. “Elements such as Arsenic (As) and Cadmium (Cd) were classified as human carcinogens by the International Agency for Research on Cancer (IARC); others like Lead (Pb) and Mercury (Hg) as probable human carcinogens, and Titanium Dioxide (TiO2) as possible carcinogen”, reads the study published in the Journal of Hazardous Materials.
Currently, quality control methods are commonly applied to the final product rather than upstream in the process. This leads to delayed contaminant detection, resulting in potential non-compliance with safety standards, and the costly disposal of entire batches of finished products. By optimising the analysis process and improving user decision-making, this approach could be adapted and scaled for high-throughput applications and industrial sorting. The study was conducted in collaboration with the Sonae Arauco group, who provided industrial context and sample materials for testing.
“This work fits into a broader vision we’ve been developing at INESC TEC, where advanced spectroscopy and spectral imaging are integrated into multimodal instruments for real-time industrial monitoring. We see strong potential in creating modular platforms that combine elemental and molecular data to support circular economy efforts in sectors like batteries, recycling, and mining,” Diana added.