Ilika plc (LON:IKA), an independent global expert in solid state battery technology, has announced that safety tests undertaken by independent expert assessors have demonstrated the superior safety of Goliath solid state cell battery prototypes relative to lithium-ion equivalent batteries.
University College London carried out the nail penetration test, a standard battery safety assessment , on Ilika’s Goliath P1 prototype cells. This destructive test creates an internal electrical short-circuit inside a cell by piercing the cell with a metal nail. The test simulates a catastrophic incident that would typically cause energy-dense lithium-ion cells with lithium nickel manganese cobalt oxide cathode chemistry (, to dangerously swell, rupture, explode, and catch fire in a process known as thermal runaway, often leading to temperatures above 600°C. Goliath P1 cells also use high-energy NMC cathode chemistry, however in the nail penetration tests the P1 cells neither exploded nor caught fire, with external temperatures remaining below 80°C.
With electric vehicles expected to play a key role in the NetZero transition, solid state batteries are anticipated to provide a safer battery solution for next-generation EVs. It is expected that a combination of improved safety performance and high energy density will reduce the complexity of battery packs. The reduction of parasitic packaging is, in turn, expected to lead to lighter and safer vehicles with longer driving range.
Testing was carried out as part of a short collaborative study, in association with the Faraday Institution SafeBatt project, which aims to develop an improved understanding of safety in next generation battery technologies. The study involves Ilika alongside researchers from the University of Oxford and University College London. The core Safebatt project explores the science of battery safety and works closely with UK battery developers and manufacturers like Ilika to inform industrial design and deployment.
A video of the test can be found here:
Graeme Purdy, Ilika CEO, stated: “Ilika has designed solid state cells intended to provide a safer alternative to high-energy lithium-ion batteries. Thanks to SafeBatt and this study, we have now observed test results which contribute to a growing body of evidence demonstrating Goliath’s superior safety performance.”
Dr James Robinson, Lecturer in Advanced Propulsion at University College London and Safebatt Project Leader, said: “These early results have exceeded our expectations in terms of cell safety. While there is still further testing to be undertaken, there seems to be an inherent safety advantage in nail penetration tests for this cell type over conventional state-of-the-art cells.”
Professor Paul Shearing, Statutory Professor in Sustainable Energy Engineering at the University of Oxford and Safebatt Principal Investigator, commented: “Embedding advanced safety testing in the development cycle for next generation batteries is critical to accelerating their deployment, and we are delighted to work with Ilika in this study to translate our understanding of battery safety to their solid state technology.”
