Sustainable lithium-ion batteries will only come about if as large a proportion as possible of end‑of‑life batteries is recovered and reused.
The new Regulation (EU) 2023/1542 sets minimum recovery rates for all major battery components, such as lithium, heavy metals, and relevant organic constituents. Reusing poorly recycled materials would, however, immediately reduce the quality of future new batteries.
The analysis of so‑called black mass, which serves as the feedstock for LIB recycling, therefore has three tasks.
- First, the purity of the recycled components must be checked for quality assurance;
- second, the black mass must be characterised before recycling to determine the content of target materials; and
- third, it must be analysed again after the recycling process to determine the recovery rates according to Regulation (EU) 2023/1542.
With a well-controlled and gentle pretreatment such as hydrowashing, the remaining mass can be a valuable substance that can be reused as anode material.
Shimadzu offers a range of analytical techniques covering the entire LIB recycling process. These include gas chromatographic methods for the analysis of volatile constituents such as organic carbonates and their degradation products. Historically, carbonates were lost in combustion‑based recycling processes. Depending on the battery type, these components account for roughly 2–8% of a battery’s weight and therefore represent a significant recycling resource. Modern methods increasingly allow carbonate recovery; their effectiveness can be assessed, validated, and optimised using GC/GC‑MS techniques.
Heavy metals and lithium are by far the most important class of recycled constituents. Previously, they have been recovered efficiently through high‑temperature processing of black mass; however, that approach is increasingly regarded as outdated. Gentle extraction methods are gaining importance, with both quality assurance and recovery rate playing a central role in these workflows. Several element‑specific spectrometers are used for this purpose. The Shimadzu product range – from basic EDX to ICP‑OES and the highly selective, sensitive ICP‑MS – provides a complete solution for metal analysis.
The residue remaining after the recycling process is often used in pyrometallurgical processing to reduce recovered metals to their metallic form or alternatively sold to refineries and chemical companies. True recycling, i.e. reusing this material for the production of LIB anode materials, is becoming increasingly important. In hydrometallurgical processing, however, acid digestions, solvent extractions, and precipitations are frequently used; the residual mass may be contaminated with traces of metals, organics, or reagents and typically requires multiple cleaning steps.
For the purity analysis of metals or organic constituents, GC‑MS or ICP‑based techniques are appropriate, while ionic species can be analysed additionally by ion chromatography (IC). IC can determine degradation products of lithium salts – for example mono‑ and di-fluorophosphate and phosphate – and can separate and quantify contaminants such as chloride, sulphate, and other anions. Shimadzu offers established IC methods for these analyses, and robust ion chromatographs are available for routine use.
