Chemists develop MRI technique for peeking inside battery-like devices

A team of chemists from the University of Cambridge and New York University has developed a method for examining the inner workings of battery-like devices called supercapacitors, which can be charged up extremely quickly and can deliver high electrical power. Their technique, based on magnetic resonance imaging (MRI), establishes a means for monitoring and potentially enhancing and the performance of such devices. The approach allows us to explore electrolyte concentration gradients and the movement of ions within the electrode and electrolyte, both ultimately a cause of poor rate performance in batteries and supercapacitors - Clare Grey The work, which appears in the latest issue of , focuses on electric double-layer capacitors (EDLCs), a type of so-called supercapacitor. These are excellent options for powering systems where fast charging and power delivery are crucial, such as in regenerative braking (for use in trains and buses), camera flashes, and in backup computer memory. "The MRI method really allows us to look inside a functioning electrical storage device and locate molecular events that are responsible for its functioning," explains Dr Alexej Jerschow, of NYU's Department of Chemistry, one of the paper's senior authors. "The approach allows us to explore electrolyte concentration gradients and the movement of ions within the electrode and electrolyte, both ultimately a cause of poor rate performance in batteries and supercapacitors," adds co-author Professor Clare Grey of Cambridge's Department of Chemistry.