The lithium value chain lacks standardized testing methods for measuring elemental composition from black mass to battery materials.
Key Takeaways
- Black-mass quality depends on a variety of factors. Battery type, origin, and composition directly impact recycling value and suitability for downstream metallurgical processes such as pyrometallurgy and hydrometallurgy
- The absence of an industrywide standard for measuring elemental composition in battery materials represents an opportunity for chemical industry expertise and standardized instrumentation methods.
- Depending on the desired end-use requirements, multiple analytical techniques offer different strengths in accuracy, speed, and applicability testing.
The quality of battery materials from natural sources, as well as from recycling, can vary widely.
Think about small-format batteries, those you would find in your smartphone, as an example.
The components in these batteries are different than, say, those found in medium-format batteries such as power tool equipment and the largest batteries found in motor vehicles.
Small-format batteries will have much higher cobalt concentrations, which can impact the downstream metallurgical processes to produce battery-grade material.
The production scrap from electric-vehicle battery production can contain more than 18 different metallic compounds.
Each of the downstream metallurgical processes requires a different feed material quality.
For example, the pyrometallurgical process involves high-temperature smelting or roasting, which usually requires burning and subsequent separation.
This is the most forgiving process.
The hydrometallurgical, or hydromet, process is achieved using aqueous chemistry, via leaching in acids or bases and subsequent concentration and purification.
This requires very high-quality and reproducible feed material.
Further down the supply chain, the battery-grade material from the above processes must be validated by the battery cell manufacturer, so it can be reused in the specific battery category.
Industry Moves Toward Classification Standards
There are different ideas in the supply chain to address recycling, black-mass and material quality variations.
Recently, I attended a presentation from the Battery Association for Supply Chain.
The association was formed in April 2021, and its mission is to enhance Japan’s battery supply chain green and competitive initiatives.
The group proposed a black-mass classification system based upon the percentages of nickel and cobalt, with subclassifications based upon battery origin (cell, module, pack), battery types, and process method.
As we all know in chemical engineering, before you can classify components, you must measure them through data collection and analysis.
What we do know is that there are currently no industry standards for determining elements in black-mass or in battery materials, either for lab analyses with grab-sample preparation or in real time during production operations.
This is clearly an area where the chemical industry can bring expertise and guidance.
Four Testing Methods Show Promise for Quality Analysis
Currently, there are three established instrumentation approaches and a newer technology called laser ablation laser ionization time of flight mass spectrometry, or LALI-TOF-MS, that are available for black-mass and battery material quality testing.
Inductively coupled plasma optical emission spectroscopy (ICP-OES) can be used to determine the elements in materials.
This technique can analyze 18 elements quickly with small sample sizes. The performance data shows that ICP-OES can be used for routine, accurate measurement of high- and low-concentration elements in samples for valuable elements, such as Co, Mn, Ni, and Li, as well as contaminant elements such as Fe, Cu, and Zn.
Another technique is to use a handheld laser-induced breakdown spectroscopy instrument (LIBS) in combination with an artificial neural network (ANN) algorithm to analyze the materials.
The combination of the ANN algorithm speed and robustness with the reliability of the LIBS instrument allows for the quantitative analysis of lithium and other metals extracted from the different types of batteries or natural sources.
Microwave digestion of samples is another technique being employed with individual sample data.
The microwave temperature, pressure, and power are controlled to provide reproducible results from sample to sample.
This approach provides the bulk composition of the material but does not show how the elements may change spatially or in depth.
Depending upon the end use, this data may be important for battery-grade material validation. It also may be applicable to demonstrate that the recycling process of mechanical pretreatment and vacuum drying does not alter the material properties.
LALI-TOF-MS is a new approach that’s effective if element changes are critical to the downstream or end-use process.
This analysis is performed under vacuum, which is important for air-sensitive products, and no “wet-chemistry” is needed, which is important in the production environment.
Finally, if you have a chance to visit a specialty chemical lab, you will find a host of instruments for determining particle size, compression and temperature stability, tensile strength, moisture, and other product-specific characteristics.
These measurements can be easily transferred into the lithium value chain processes because, in reality, it’s all about producing high-quality and validated specialty chemicals for battery cell manufacturing.
Barry Perlmutter has over 40 years of technical engineering and business marketing experience in SLS, including filtration & separation, centrifugation, and process drying, as well as for lithium production, battery materials manufacturing, and battery recycling. As our Chemical and Mechanical Process Engineering Expert, Barry has supported clients across the North American battery value chain and is available to support your organization for Q&A’s, on a project basis, or through ongoing support. Click below to schedule a quick discovery call to see how Barry, or our other SMEs, can support your team.
