PhD student at ESRF - safety of high energy density batteries following real-world cycling

Thesis subject: Understanding safety of high energy density batteries following real-world cycling.

The safety of batteries is imperative in a range of applications that will support Net Zero, from electric vehicles to grid scale storage. Manufacturers are required to certify cells at the beginning of life to demonstrate their safe performance against international safety standards, However, in field applications, batteries are cycled under a range of conditions leading to a diversity of degradation routes that are expected to have profound impact on their state of safety. There is little data that quantifies how the batteries state of safety changes as its state of health declines.

In this PhD project at ESRF and The University of Oxford in we propose a unique portfolio of measurements to improve this understanding using beamline ID19: a 150 m-long ESRF beamline dedicated to high resolution X-ray imaging (radiography and microtomography) (using) partially coherent hard X-rays. The beamline combines a broad range of cutting-edge experimental setups with intense polychromatic illumination for (high-speed) phase contrast X-ray imaging at high photon energies: perfectly suited for in situ studies of materials, operando processes and engineering devices as well as development of new imaging modalities. 

The studentship will take advantage of international partnership with Fraunhofer EMI, NREL and CEA which includes performing experiments at the world-wide test facility at ESRF-ID19 for in situ studies of battery abuse testing. Complementary work will be carried out by means of XRD-CT at beamline ID15a to understand the state of ageing of batteries after real-world cycling, prior to abusive experiments.  

This studentship is consisting of 3 work packages:

Work Package 1: Correlative Metrology: underpinning methods development in X-ray and neutron tomography, X-ray diffraction CT and high-speed X-ray imaging. The candidate will establish correlative work-flows with hardware and software integration to enable translation of samples, and super position of data across X-ray and neutron beam lines.

Work Package 2: Benchmark State of Safety (SoS): the candidate will focus on establishing benchmark safety testing on pristine cells, contributing to advancing understanding of SoS at beginning of life and further developing ‘gold-standard’ certification protocols using the unique high speed X-ray imaging capability at ID19 and certified failure testing rigs.

Work Package 3: Accelerated Ageing and Dynamic SoS: in the final work package, the candidate will age batteries according to systematic accelerated stress tests (ASTs), providing a broader sample matrix that more accurately represents the heterogenous population of batteries in real-world deployment.

Further information may be obtained from: Prof. Paul Shearing (email: paul.shearing@eng.ox.ac.uk), from Dr. Alexander Rack (+33 476 88 1781, email: alexander.rack@esrf.fr) and from Dr. Marco Di Michiel (+33 476 88 2123), email: dimichie@esrf.fr.]