Advancements in Lithium Quantification for Complex Matrices: Analytical Techniques, Interference Mitigation, and Comparative Performance

Abstract

Lithium has emerged as a critical element in modern technology, particularly in energy storage, electronics, and industrial applications. Accurate quantification of lithium in complex matrices such as ores, brines, and recycled battery materials—is essential for resource evaluation, process optimization, and quality control. However, the presence of chemically similar elements (e.g., sodium, potassium, calcium) introduces significant spectral and chemical interferences, complicating analytical measurements. This review provides a systematic comparison of classical and modern techniques for lithium determination, including flame photometry, atomic absorption spectroscopy (AAS), inductively coupled plasma–optical emission spectrometry (ICP-OES), inductively coupled plasma–mass spectrometry (ICP-MS), ion-selective electrodes (ISE), and chromatographic methods. Special emphasis is placed on interference mitigation strategies such as selective extraction, ion exchange, and matrix-matched calibration. Recent advancements in hyphenated techniques (e.g., LC-ICP-MS, IC-ICP-MS), machine learning-driven interference correction, and portable analytical tools are also discussed. By consolidating current knowledge and identifying future research directions, this review serves as a practical guide for selecting and optimizing lithium quantification methods in diverse analytical contexts.