Lithium Battery Recycling: An Essential Step for a Sustainable Future

Lithium-ion (LI) batteries are an integral part of modern society, powering everything from smartphones and laptops to electric vehicles and energy storage systems. As the demand for these batteries continues to rise, so does the need for effective recycling solutions. In fact, many countries and regions have implemented or are considering regulations that require proper disposal and recycling of lithium batteries, encouraging the development of a robust recycling industry.

The Reality of Recycling

When a LI-battery enters the recycling stream, it goes through initial processing steps, such as shredding, to separate the complex mixture of materials into appropriate groupings for recycling. These initial steps typically remove 50-60% of the battery mass by separating out materials like steel, binders and some plastics. What is left behind is a black powdered material referred to as black mass. This material contains all the critical materials used to make the battery cathodes and anodes and has a high concentration of graphite. Recyclers process the black mass, converting it into saleable metals that can return to the upstream processes or enter the supply chains of other industries.

The advantages of a circular approach for the battery industry are both environmental and economic. Recovering and reusing critical materials from spent batteries keeps them out of landfills and can help reduce the reliance on virgin resources which are finite and costly. Unfortunately, the technology that makes these batteries so effective for use also makes them more challenging to recycle. One of the key challenges is the complexity of the batteries themselves. Lithium-ion batteries consist of many components and materials, including metals, plastics, and electrolytes, making the recycling process more intricate compared to traditional lead-acid batteries.

To address this challenge, researchers and companies are continually developing innovative recycling technologies. These technologies aim to streamline the dismantling and separation of battery components, as well as improve the recovery of valuable materials. Whether you are using established processes or seeking to innovate improvements, one thing is clear, processes can all be made more efficient using an understanding of the composition of the black mass being processed.

Analyzing Black Mass

Accurate information about the concentrations of the major elements and any high-level impurities present in Black Mass can drastically improve recovery processes. Unfortunately, black mass is comprised of graphite, ash, lithium, cathode materials and contaminants, which can each complicate sample preparation and analysis.

Sample Preparation

There are several options for preparing black mass for analysis. Each has its own benefits and challenges:

• Microwave digestion – The high graphite content of black mass can create a challenge for this technique. High temperatures, aggressive acids and extended digestion times are required but are not a guarantee that the graphite reliably goes into solution.
• Fusion – Sodium or lithium fusion of black mass is another time-consuming option that requires aggressive conditions to ensure a homogenous bead. If a bead is successfully formed, however, it readily dissolves in acid, simplifying the next analysis steps. One major drawback of this technique, however, is you cannot measure boron (sodium fusion) or lithium (lithium fusion).
• Leaching – This technique leverages a thermal digestion block, like the SNRG Block by AnalytiChem, to leach metals into solution, leaving carbon-based materials. Like the other techniques mentioned, it requires extended processing times, but this technique is easier to scale to multiple samples simultaneously.

Because of the complex composition of black mass, the best sample preparation technique might vary depending on the battery types being recycled: LCO (Lithium Cobalt Oxide), LMO (Lithium Manganese Oxide), NMC (Lithium Nickel Manganese Cobalt Oxide), LFP (Lithium Iron Phosphate), NCA (Lithium Nickel Cobalt Aluminum Oxide), LTO (Lithium Titanate Oxide), or a mixture of these waste streams. But no matter the black mass composition, introducing a quality control (QC) sample into the sample preparation process is essential to assure the accuracy and precision of a chosen sample preparation process. QC samples have a known concentration and are processed and analyzed alongside test samples, enabling the process to be monitored and any discrepancies to be quickly investigated and addressed. The AnalytiChem Black Mass CRM product family is ideally suited for use as a QC check and for use when establishing a sample preparation process. ISO 17034 accredited and matrix-matched, this family of real-world materials currently includes two NMC compositions with certified values for majors, minors and trace contaminants.

Elemental Analysis

Once black mass is prepared into a homogeneous sample, Inductively Coupled Plasma (ICP) paired with a detector is the most common analytical method for analyzing the key elements of interest for recycling, including Lithium, Cobalt, Manganese, and Nickel. ICP is a comparative liquid analysis technique requiring calibration with high-quality standards, such as certified reference materials, to assure accurate analysis.

X-ray Fluorescence Spectrometry (XRF) may also be used at an earlier stage in the recycling process to screen and categorize waste streams before final QC analysis by ICP.

Either analysis methodology achieves the most accurate results when paired with matrix-matched certified reference materials. These reference materials are generated from real-world materials and certified using multiple laboratories to achieve consensus values. The complexity of certifying these materials means that laboratories should only use reference materials from manufacturers who are experts at this process and have achieved ISO 17034 certification.

How does AnalytiChem Help?

AnalytiChem supports analysis throughout the battery industry. As an ISO 17034-accredited manufacturer, we offer a variety of certified reference materials, including ICP standards and custom real-world, matrix-matched materials. We also produce sample preparation equipment and consumables. If you are working with complex materials, AnalytiChem is the perfect partner to help enable your analysis. If you have any questions about matrix matched reference materials or would like to learn more about any of our products, don’t hesitate to contact our team.