Review of analytical lithium detection and quantification methods along the lithium value chain

Abstract

With the invention of the lithium‐ion battery, the demand for lithium raw materials is increasing due to the electrification of the transport sector (EV batteries) and the expansion of renewable energies and their storage. Technological progress is accompanied by new demands on analytical methods for lithium, particularly with respect to spatially resolved analysis. Knowledge of the advantages and disadvantages of the existing methods is important for a wide range of disciplines involved in lithium extraction and processing, from geoscience to battery manufacturing and recycling. Parameters such as spatial resolution, detection limits, and analytical uncertainty vary greatly across a wide range of commonly used methods. This article reviews a selection of suitable state‐of‐the‐art analytical methods for different scales of spatial resolution and detection of lithium for a variety of lithium‐bearing materials along the lithium value chain. The various materials differ greatly in terms of their lithium content by more than 5 orders of magnitude and also vary in their structural composition. Moreover, the spatial resolution required for any particular application is highly variable. Therefore, we emphasize that it is advisable to consider the combination of lithium detection limits with the spatial resolution of all relevant methods to develop the most suitable approach to address any task of lithium analysis. In many cases, it will be necessary to use a combination of methods to fully characterize a geological or artificial lithium‐bearing material. We also note that the availability of suitable reference materials, which is a prerequisite for accurate quantification across different lithium concentration ranges and matrices, and the lack of standardized procedures for lithium content determinations present an important research gap that requires the community's attention.