January_February_2022_AMP_Digital

A D V A N C E D M A T E R I A L S & P R O C E S S E S | J A N U A R Y / F E B R U A R Y 2 0 2 2 3 0 ICP-OES. Quantification using ICP- OES is based on the measurement of ex- cited atoms and ions. This method can detect a wide range of metal (and sev- eral non-metal) elements down to low parts per billion (ppb) levels, with some elements detectable at the sub-ppb lev- el. It can be used to perform simultane- ous multi-element analysis of samples with complex matrices, so it is well-suit- ed to battery material analysis. As ICP-OES can handle direct analysis of higher sample matrix con- centrations than ICP-MS, it is ideal for quantifying the high-concentration ma- trix elements in battery cathode mate- rials (e.g., Li, Mn, Co, and Al). The high stability of ICP-OES also enables con- sistent results to be achieved with ex- cellent precision for both matrix and impurity elements, with a typical mea- surement precision of < 1% relative standard deviation on cathode mate- rials with a specified matrix element content. ICP-OES can be applied to the de- tection and quantification of a range of elemental impurities in cathode, elec- trolyte, and anode materials down to ppb levels. For example, ICP-OES can be used to rapidly determine major el- ements and trace impurities in ternary cathode materials for QA/QC confirma- tory analysis in the cathode active ma- terial production process [2] . The major advantage of ICP-OES is its ability to enable laboratories to per- form the measurements they need in a single method, mak- ing it ideal for higher sample throughput. In addition, as ICP- OES does not require a specialist with high technical expertise, it can be used with ease in testing lab- oratories. ICP-MS. Anoth- er analysis method, ICP-MS, is a fast, high- ly sensitive multi- element technique capable of detecting a wide range of ele- ments down to parts per trillion (ppt) levels. The technique is beneficial for detecting electrically conducting metal impurities such as so- dium (Na), potassium (K), magnesium (Mg), and calcium (Ca), as well as the transition metals that can disrupt and degrade battery performance. The current generation of single- and triple-quadrupole ICP-MS instru- ments provides robust and consistent sample introduction with advanced col- lision/reaction cell-based spectral in- terference removal technology. These features enable accurate and precise re- sults in even the most complex battery material sample matrices. Because it can be easily interfaced with IC and HPLC systems, ICP-MS is also ideal for identifying and quantify- ing metal-based degradation species in Li-ion battery electrolytes at very low concentrations. ICP-MS can also be used to study the buildup of impurities on the anode, which are known causes of battery deg- radation. Cathode materials such as LiMnO 2 degrade during charging/dis- charging cycles, causing a buildup of Mn-based species on the anode. By hy- phenating ICP-MS with IC, ionic species in the anode deposits (e.g., permanga- nate) can be identified and quantified. CONCLUSIONS Detecting and quantifying impu- rities in Li-ion battery production are key to improving the quality and per- formance of battery technology. In production environments as well as re- search laboratories, ICP-OES provides robust, precise, and high-throughput measurement of both high-concentra- tion matrix elements and trace impuri- ties in cathode materials. ICP-MS-based methods are ide- al for detecting and quantifying the ex- tent of degradation of key Li-ion battery components such as cathodes, anodes, and electrolytes. ICP-MS is also suitable for detecting trace-level impurities in battery materials and identifying met- al-based degradation species in battery research. ICP-MS systems offer the sensitivi- ty required to detect impurities in Li-ion battery materials at the level required by national standards. Moreover, their ease of use allows them to be adopted efficiently in high-throughput labora- tories. Ultimately, the future of battery technologies and their ability to provide sustainable energy rests on researching new ways to improve their develop- ment and production. Workflows based on ICP-OES and ICP-MS provide new solutions for manufacturers to enhance the quality of Li-ion batteries, paving the way for improved performance and safety. ~AM&P For more information: Simon Nelms, product marketing manager, Trace Elemental Analysis, Thermo Fisher Scientific, Stafford House, Boundary Way, Hemel Hempstead, UK, HP2 7GE, simon.nelms@thermofisher.com , www. thermofisher.com/tea. References 1. YS/T 798-2012: China National Non-ferrous Metal Industry Standards: Lithium, Nickel, Cobalt, Manganese, Oxide, Ministry of Industry and Information Technology of the People’s Republic of China. 2. Jingfang He, et al., Sensitive De- termination of Elements in Lithium Batteries using the Thermo Scientific iCAP PRO XP ICP-OES, [Online]. Available: https://assets.thermofisher . com/TFS-Assets/CMD/Appl ication- Notes/an-73872-icp-oes-elements- lithium-batteries-an73872-en.pdf. The latest generation of ICP-OES and ICP-MS instruments provides complete solutions for all elemental analysis aspects of Li-ion battery research, development, and production.