The Measurement of the Coating Uniformity of Lithium Iron Phosphate Cathodes on Metal Substrates with Terahertz Time-domain Spectroscopy

For the first time, the thickness uniformity of lithium iron phosphate (LFP) cathodes are measured using terahertz time-domain spectroscopy. Cathodes are widely manufactured with cobalt, however providing cobalt material comes with supply and health issues. LFP cathodes are introduced as an alternative to tackle this challenge. The aim is to use terahertz pulses to generate an on-line tool to undertake manufacturing process control. Different thickness of cathodes compressed to different densities is measured and the uniformity of their coating is inspected.