The project

The European Green Deal targets net zero CO2 emissions of greenhouse gases in Europe by 2050, specifying zero emissions from new cars by 2035. Electrification of the automotive industry is key to meeting these goals, but rapid advances in energy storage technologies such as lithium-ion batteries are required to realise this. Many new materials combinations for battery electrodes are emerging that can begin to address performance targets, but lifetime issues remain problematic. Hence, there is an urgent need for traceable analytical techniques to decipher structure-behaviour relationships and elucidate degradation and failure mechanisms to improve battery performance by design, rather than empirically. 

Quantification of elemental composition, and determination of oxidation and chemical binding states, coordination and phase structure are crucial for an enhanced understanding of battery electrode degradation . Moreover, investigations must be conducted in real-time, allowing aging mechanisms to be linked to battery state of charge (SoC) and state of health (SoH). Currently, degradation studies are performed post mortem, using ex situ methods where the cell is disassembled, leading to chemical modification which can distort the result. 

To avoid that, operando methods, where electrode materials are characterised simultaneously during cell charge-discharge, are needed. Whilst some operando methods are available, they are not sufficiently reliable or quantitative to allow confident data interpretation. Moreover, there is a need for new hybrid operando methods, where multiple measurands are synchronously probed during electrochemical cycling, to establish causal links between materials properties and their impact on cell performance. Such advanced measurements bring new challenges as they require special sample environments such as dedicated electrochemical cells with thin probing windows, while ensuring that the electrochemical behaviour remains unperturbed. 

Hence, there is a need for establishing a robust, validated metrological framework for operando metrology, that can be transferred to battery developers and demonstrated through industrial case studies.  

1. To develop traceable chemical, physical and structural analysis methods for ex-situ characterisation of high-capacity energy storage materials (e.g Li-ion and Li-S) and components (e.g. Cobalt, Nicklel, Manganese) with a focus on x-ray spectroscopic techniques. This includes the fabrication and qualification of at least 3 calibration samples and verification by interlaboratory studies (post mortem). A relative uncertainty in elemental composition of below 10% will be targeted. 

2. To establish a Good Practice Guide for current and emerging in operando spectroscopy methods including X-ray and vibrational spectroscopy, validated by ex-situ analysis and round robin tests, in order to establish and, where possible improve, experimental repeatability and accuracy with respect to elemental and species analysis of battery materialsies. In addition, to develop measurement protocols to assess the influence of cell geometry, electrode configuration, and measurement parameters on observable phenomena, as well as to assess the extent and influence of vacuum ultra-violet (VUV) or X-ray radiation damage.  

3. To develop novel dynamic electrochemical approaches combined with in operando spectroscopy and dimensional metrology for the correlative assessment of the relationships between material structure and cell performances.  

4. Based on the results of Objectives 1-3, to develop novel in operando instrumentation and hybrid methodologies for multi-parameter spectro-electrochemical characterisation of materials and components for high-capacity energy storage (e.g. in Li-ion and Li-S battery systems). To investigate the causal relationship between electronic/molecular- and microstructure information and charge carrier dynamics as measured with electroanalytical methods, to gain information on the state of health and state of charge. 

5. To facilitate – in cooperation with the EMPIR 20NET01 Clean Energy – the take up of the data and measurement infrastructure developed in the project by the measurement supply chain (NMIs, DIs, calibration laboratories), standards developing organisations (e.g. ISO/TC 201) and key end users (materials suppliers and battery manufacturers). To promote technology transfer of the project outputs as lab-based alternatives to synchrotron radiation-based methods, towards industry and manufacturers.  

• WP1: Traceable ex situ characterisation of high-capacity energy storage materials

• WP2: Establishing good practice guide for current operando spectroscopy and diffraction methods

• WP3: Development of novel dynamic electrochemical analysis approaches for combination with operando spectroscopy and dimensional metrology

• WP4: Development of novel operando instrumentation and hybrid methodologies for multi-parameter characterisation

• WP5: Creating impact

• WP6: Management and coordination