Scientists have used X-rays to document how the internal structure of a lithium-ion battery fails during thermal runaway.
Researchers exposed two commercial lithium-ion batteries to extreme heat, then used computed tomography (CT), radiography and thermal imaging to detail the results.
The study examined key degradation modes including gas-induced delamination, electrode layer collapse and propagation of structural degradation as they occurred.
Previous tests analysed battery failure post-mortem with static images or under normal operating conditions.
The study by UCL, ESRF The European Synchrotron, Imperial College London and the National Physical Laboratory, was published in Nature Communications.
It is hoped the findings will lead to major improvements in the design and safety of lithium-ion batteries.
Corresponding author, Dr Paul Shearing of UCL Chemical Engineering, said: “We pushed the batteries a long way to make them fail by exposing them to conditions well outside the recommended safe operating window.”
The team now plans to study what causes battery failure at a microscopic level.