Thermal Runaway of a Li-Ion Battery Studied by Combined ARC and Multi-Length Scale X-ray CT

Drasti Patel, James B. Robinson, Sarah Ball, Daniel J. L. Brett and Paul R. Shearing - Department of Chemical Engineering, University College London / The Faraday Institution, Harwell Science and Innovation Campus / Johnson Matthey Battery Materials, Oxford Science Park

Lithium ion battery failure occurs across multiple length scales. In this work, the properties of thermal failure and its effects on electrode materials were investigated in a commercial battery using a combination of accelerating rate calorimetry (ARC) and multi-length scale X-ray computed tomography (CT). ARC measured the heat dissipated from the cell during thermal runaway and enabled the identification of key thermal failure characteristics such as onset temperature and the rate of heat generation during the failure. Analysis before and after failure using scanning electron microscopy (SEM) and X-ray CT were performed to reveal the effects of failure on the architecture of the whole cell and microstructure of the cathode material.

How Amira-Avizo Software is used

The acquired datasets were reconstructed using CT Pro 3D software with a built in filtered back projection algorithm with subsequent data was visualised using Avizo Fire 9.2. […] Reconstructed data was processed using Avizo Fire 9 software (FEI VSG, France). After reconstruction a non-local means filter was applied to the images to reduce noise and preserve phase boundaries. Phases were separated based on their grey scale values, where weakly attenuating materials are displayed in shades of grey and highly attenuating materials in white. Binary images and volume renderings, are subsequently used for measurements of porosity and PSD using Avizo Fire 9’s label analysis tool.