New Battery Technology Delivers Additional Power to Implantable Medical Devices

These devices depend on batteries with anodes that operate at higher voltages than those in typical lithium-ion cells, but current graphite-based anodes have limited energy density. In a promising development, researchers have discovered that introducing neodymium into the anode material can significantly increase a battery’s energy density, potentially expanding the capabilities of implantable medical technologies.

The breakthrough was achieved by a research team from McGill University (Montreal, Canada) along with industry partner, Medtronic (Dublin, Ireland). Their work is focused on advancing battery performance for medical devices, balancing the need for increased energy storage with the strict safety requirements of implants used in the human body. The innovation centers on modifying the anode—the component that releases and absorbs lithium ions during charging and discharging—by adding small amounts of the rare-earth element neodymium. In previous studies, this adjustment yielded a 20% increase in energy density. In their latest study, the team used the Canadian Light Source (CLS) at the University of Saskatchewan (Saskatoon, Canada) to investigate the underlying mechanism. With the help of the CLS’s HXMA beamline, they observed that even trace amounts of neodymium caused significant structural changes throughout the anode.

These structural disruptions at the microscopic level appear to be the key to enhanced energy storage. However, the researchers also found signs of instability related to the electrolyte component of the battery, which could impact its long-term usability. As a result, the team is now shifting focus toward improving battery lifespan while maintaining energy gains and safety. The implications of this work are substantial. Enhancing the energy density of batteries without increasing size or compromising safety could lead to longer-lasting implantable devices and enable entirely new applications. The research also suggests pathways for improving commercial battery designs, especially in fields where size and performance are both critical.

"There's definitely continued work that needs to happen, to make these commercially viable. But already the gains that we've made show that the energy (produced by the new type of battery) would enable new or different medical applications," said Eric McCalla, an associate professor in McGill University’s Department of Chemistry.

Related Links:
McGill University
Canadian Light Source
Medtronic