The first of many ambitious goals from the recent UN Climate Change Conference (COP26) in Glasgow is to secure global net zero emissions by midcentury. It translates to a strong acceleration toward the use of renewable energy sources, for a complete replacement of fossil fuels.
Included is the accelerated adoption of electric vehicles, which are expected to become more and more popular in the coming years, with a consequent explosion of lithium-ion (Li-ion) battery consumption.
Rechargeable Li-ion batteries (LIBs) are today used widely in many electronic devices and in electric vehicles due to their high energy density and low self-discharging. The expected rapid-growing demand will definitely pose new environmental and economic challenges like spent-battery waste management and effective recycling processes for valuable components. A LIB is made of a graphite negative electrode, a positive electrode with layered metal oxides and an aprotic organic electrolyte. The electrolyte consists of a conducting lithium salt dissolved in a mixture of highly flammable carbonates. Even if LIBs are considered relatively safe, more efforts will be spent as well on flame retardant agents to reduce flammability and improve safety.
The European Commission is working on a new EU regulatory framework for batteries in order to secure the sustainability and competitiveness of battery value chains. It would introduce mandatory requirements on sustainability (such as carbon footprint rules, minimum recycled content, performance and durability criteria), safety and labeling, and requirements for end-of-life management.
In this scenario of increasing R&D investment and more stringent quality requirements, from LIB-supply industry to car manufacturers, advanced analytical solutions are critical to support new technological developments, as well as assure high production quality.
Innovation in analytical solutions is key
As the world leader in advancing science, Thermo Fisher Scientific offers a full spectrum of analytical solutions and services to fulfill the most demanding analytical needs to advance in research, product development, production processes and quality assessment. These solutions include X-ray photoelectron spectroscopy (XPS/ESCA), electron microscopy (SEM, TEM and FIB-SEM), vibrational spectroscopy (FTIR, Raman and NIR), chromatography and mass spectrometry (GC-MS, HPLC, LC-MS), trace elemental analysis (ICP-OES, ICP-MS), microCT, nuclear magnetic resonance (NMR), X-ray diffraction, X-ray fluorescence, rheometry, viscometry, extrusion and torque rheometry. A compendium of application notes provides in-depth reports on analyses aimed at monitoring and improving the performance of LIBs.
For example, the assessment of raw material purity and composition is critical before and during battery development and production processes. In this respect, trace elemental analysis, and in particular ICP-OES and ICP-MS, plays a key role to detect and quantify elements in lithium salts and alloys, as well as to detect detrimental impurities in the electrolyte.
To know more and to access additional resources, don’t miss this recent Analyte Guru blog post on the role elemental analysis plays along the entire Li-ion battery lifecycle.
The role of gas chromatography
Any time we are dealing with organic volatile components, gas chromatography (GC) is the analytical technique for highly sensitive qualitative and quantitative characterization.
The electrolyte in a Li-ion battery is the carrier of positive lithium ions between the cathode and anode. Electrolyte solutions must enable the Li-ions to transport freely, requiring both high dielectric constant and low viscosity. For this reason, suitable electrolyte solutions are a mixture of cyclic and linear carbonate esters, in which the exact composition plays a key role in the performance of lithium-ion batteries.
Gas chromatography coupled to mass spectrometry (GC-MS) is the suitable technique to monitor the electrolyte composition and the ratio of cyclic and linear carbonate, to ensure optimal performance. The Thermo Scientific™ ISQ™ 7000 single quadrupole GC-MS offers an easy to use solution for qualitative and quantitative carbonates profiling, ideal in QA/QC testing as well as in development stage.
Additionally, gas chromatography is useful in Li-battery aging studies and degradation processes elucidation. Initial charge/discharge processes in batteries produce a variety of gas components that have an impact on battery performance after long-term use. Therefore, the gas composition produced by batteries provides important information about possible deterioration and the performance of different battery formulations. The Thermo Scientific™ TRACE™ 1310 GC in a multi-column multi-valve configuration is ideal to detect inorganic gases and light hydrocarbons from swelling batteries.
Advanced GC-MS technology is also available for research laboratories to investigate battery degradation processes through the identification of intermediates and unknown degradation products. This is the case of the Münster Electrochemical Energy Technology (MEET), the battery research center at Münster University, which works to address electrolyte aging, a major factor affecting Li-ion battery life. Using the Thermo Scientific™ Q Exactive™ GC Orbitrap™ GC-MS/MS system, MEET’s Analytics and Environment division is gaining a broader and deeper understanding of their samples that, in turn, provides new insight into the complex reaction mechanisms involved in electrolyte aging.