Is X-ray Fluorescence (XRF) Useful for Analyzing Materials in the Production of Lithium-Ion Batteries?

Lithium-ion batteries are made of a variety of materials utilizing many lithium-based chemistries – including lithium cobalt oxide, lithium nickel manganese cobalt oxide, lithium manganese oxide, lithium iron phosphate, lithium nickel cobalt aluminum oxide, and lithium titanate – depending upon intended use.  The chemistries must contain the right elements in precise amounts to meet customer specifications and perform as expected.

Handheld X-ray fluorescence spectrometry (HHXRF) is a technology that can identify the presence and measure the concentration of elements from magnesium (atomic number 12) to uranium (atomic number 92)….which makes it useful during several phases of the battery production process.

Lithium is Not the Only Element Needed for Battery Production

The element Lithium, an alkali metal, makes up only 0.0007 percent of the earth’s crust, according to the Jefferson Lab.  It was discovered in the mineral petalite, and it’s only found in minerals and salt pans.

Lithium is atomic number 3 on the periodic table, and it cannot be measured with HHXRF technology. So, why is HHXRF important to lithium-ion battery (LiB) production?

HHXRF is important because, as mentioned, LiBs are made of many materials beyond lithium itself. Some of these materials are nickel, manganese, or copper (or even cobalt which is scarcer than lithium). Lithium metal alloys can improve the strength of some of those metals and make them lighter. And HHXRF is a useful tool for metal alloy analysis.

XRF in the Mining of Battery Materials

The use of HHXRF in the LiB value chain starts in exploration and mining of cobalt, copper, and manganese. The technology enables geologists to discover and assess new deposits of those commodities. Later in the process, it helps mining companies control the grade of extracted materials.

Handheld XRF analyzers help users reliably examine ore samples in open pits and underground mines – achieving the accuracy required to provide defensible information for process oversight, quality assurance, and various other operational decisions (such as grade control). HHXRF technology can help ascertain the viability of lower grade resources and find localized high-grade enrichments, delineate ore from waste boundaries to reduce the randomness of digging, and obtain defensible data and minimize the need to send samples to external testing labs.

XRF for Quality Control in Battery Production

A second common application of HHXRF in the Lithium-ion battery production process is the verification of materials employed in equipment used for raw material and LiB cells manufacturing. In fact, the use of wrong alloy in critical parts such as mixing paddles of blenders or slitter blades can cause metal contamination of the battery material and be the origin of electrical short-circuits and failures.

Material verification and alloy grade identification in QA/QC is key to ensuring product reliability and safety. Increasingly stringent regulation makes testing 100% of critical materials a best practice for today’s manufacturers, including LiB producers.

Raw materials used in the manufacturing of battery cells – such as cathode active material, aluminum foils and copper foils used as current collectors – can be analyzed within seconds to a few minutes using HHXRF, to check the consistency of their composition.

When Lithium-Ion Batteries are Scrapped

HHXRF is probably the most useful at the end of the LiB value chain. It helps lithium-ion battery recycling companies to quickly identify the content of recycling products such as black mass, obtained from shredding and sieving end of life batteries. It’s used to determine the economic value of black mass based mainly on nickel cobalt, copper and manganese content. It also helps companies recovering those metals to optimize their recycling process by reducing waste and improving yield.

Battery recycling is an essential component of a sustainable battery manufacturing ecosystem. It helps to reduce the environmental impact of mining and reduces our reliance on new sources of raw materials. (Read Role of Battery Recycling in Meeting Raw Material Demand.)

And of course, battery manufacturers can use HHXRF to check the incoming scrap that will be used in the production process, to make sure it has not been contaminated with unwanted materials.

Summary

X-ray fluorescence spectroscopy is a useful tool throughout the lithium-Ion battery production process, from exploration and mining of the raw materials. It helps confirm the content of incoming materials and outgoing finished products as well as measure the elemental content in recycled battery materials.