Through controlled application of an electric field to the ceramic body during sintering, Lucideon's Flash Sintering technology allows peak temperature to be significantly lowered and the process cycle accelerated, thereby potentially reducing the cost of ceramics manufacture.  It also has the potential for improvement in microstructure, increased ceramic strength, wall thickness reduction, and lower cell resistance.

Carried out over a twelve-month period, the project found that Flash Sintering can significantly lower the furnace temperature required to process beta alumina shapes by 300°C, thereby increasing productivity by up to three times with lower furnace costs and longer furnace life. New battery concepts involving thinner-walled electrolyte discs and tubes may also become possible with this technique.

The feasibility study has demonstrated the following five key parameters:

• Flash sintering of tubes and discs at lower peak temperature
• Control of sintering conditions to avoid locally high currents
• Densification of sintered bodies (although further optimization is needed for full density and target strength)
• Conversion to the high-conductivity beta-alumina phase (again requiring optimization for full conversion and maximum conductivity)
• Scoping of approaches to sintering larger batches of ceramic components.

Stuart MacLachlan, head of R&D at Lucideon, said:

“The challenge was to apply Flash Sintering to beta-alumina sintering whilst retaining its distinctive sodium ion conducting properties that are essential for use in batteries.

"The results were very positive and we are considering approaches to develop this unique technology further for exploitation in the UK."

Steve Heavens, R&D director of Ionotec, said:

"UK government support has enabled Ionotec and Lucideon to explore the possibilities of using an advanced technique to improve manufacturing technology for sodium batteries that will be needed to address critical issues in zero-carbon energy generation and storage."

The project 'Field Enhanced Sintering of Beta Alumina for Electric Vehicle Battery Applications' (FESBEV) was co-funded by Innovate UK, the UK's innovation agency, on behalf of UK Research and Innovation under the Faraday Battery Challenge programme.