Single quadrupole-inductively coupled plasma mass spectrometry (ICP-MS) as a tool for process control in lithium battery recycling

Importance of the topic

As demand for electric vehicles and stationary energy storage grows, efficient recovery of high-purity anode materials from end-of-life lithium-ion batteries becomes critical for sustainable supply chains and zero waste targets. Trace impurities such as transition metals and halogens can degrade performance of recycled graphite, necessitating robust analytical control in the recycling process.

Study objectives and overview

This study evaluates the performance of a single quadrupole inductively coupled plasma mass spectrometer (ICP-MS) equipped with argon gas dilution and helium kinetic energy discrimination for rapid, interference-free analysis of 44 elements in graphite anode samples digested in aqua regia. It aims to demonstrate sensitivity, accuracy, and long-term robustness under high acid matrix conditions.

Methodology and instrumentation

• Sample preparation: Microwave-assisted digestion of graphite powders in aqua regia, diluted to about 1% total dissolved solids.
• Instrument: iCAP RQplus single quadrupole ICP-MS with AGD-low mode, PLUS torch and EasyClick peristaltic pump.
• Collision cell: Helium KED for removal of polyatomic interferences in HCl-rich samples.
• Autosampler and software: iSC-65 autosampler with Step Ahead feature and Qtegra ISDS for automated tuning and sequence control.
• Calibration: Multi-element standards in mixed nitric/hydrochloric acid; internal standards added online.

Main results and discussion

Limits of detection were below 0.1 microgram per liter for most elements, with calibration linearity (R2) above 0.997. Spike recoveries ranged from 84 to 104 percent with relative standard deviations below 4.4%. Continuous analysis of 189 solutions over nine hours showed calibration verification recoveries between 88 and 109 percent and stable internal standard responses, demonstrating high throughput capability and analytical robustness.

Benefits and practical applications

The optimized method allows direct measurement of complex recycling solutions without manual dilution, saving time and reducing contamination risks. High matrix tolerance and interference removal ensure reliable monitoring of trace contaminants, essential for process control in battery recycling and quality assurance of recovered materials.

Future trends and potential uses

Integration of advanced ICP-MS technologies such as collision/reaction cells, higher-resolution mass analyzers, and automated sample handling will further enhance throughput and accuracy. Method adaptation to other battery chemistries and recycling streams, as well as coupling with chemometric tools for real-time process feedback, can drive next-generation sustainable recycling workflows.

Conclusion

The single quadrupole ICP-MS with argon gas dilution and helium KED provides a fast, accurate and robust solution for multi-element analysis in challenging high-acid battery recycling samples. Its high sensitivity, minimal sample preparation and automated operation support efficient process control and improved material recovery in lithium-ion battery recycling.

Reference

• Magampa P P, Manyala N, Focke W W. Inductively coupled plasma mass spectrometry in battery recycling. J Nucl Mater. 2013;436:76-83.
• Thermo Fisher Scientific. Product Spotlight: iCAP Qnova Series ICP-MS PLUS Torch. Technical note 44485.
• Thermo Fisher Scientific. Achieving robustness using argon gas dilution with ICP-MS. Technical note 001705.
• Thermo Fisher Scientific. iSC-65 Autosampler and Qtegra ISDS Software. Product Spotlight 001587.