Wireless charging technology developed by Resonant Link

When Grayson Zulauf worked for a commercial electric vehicle company in 2013, he recalls being excited about the prospect of using wireless technologies to recharge EV fleets. But while he was earning his PhD in electronics at Stanford years later, Zulauf realized that wireless technologies were greatly needed in the medical industry to recharge batteries of implanted medical devices such as pacemakers, implantable cardioverter-defibrillators and insulin pumps.

“Right now these batteries are replaced either with a surgery or you have a wire called a driveline that's permanently installed in your stomach,” says Zulauf. Drivelines connect an implanted device to a battery located outside the body. “And both of those kill people and cause infections,” Zulauf, 29, a Forbes 30 under 30, 2021 listee, adds. To ensure that patients with implanted devices don’t have to undergo invasive procedures for battery recharge and replacement, in 2017, he cofounded a company called Resonant Link along with Aaron Stein and Phyo Aung Kyaw, both PhD students at Dartmouth University at the time as well as their professor Charlie Sullivan, after he met them at a conference in Italy. 

“Wireless charging is a safe, non-invasive way of recharging batteries for this growing class of implantable devices,” says Zulauf.

The company announced Wednesday that it has raised a $9.3 million seed round. The round was led by The Engine, the venture firm spun out of MIT that invests in early-stage tech. Volta Energy Technologies, along with Emerson Collective, Scout Ventures, Urban Us and FreshTracks Capital also participated in the round.

Wireless chargers are most commonly used to recharge phones batteries and work on centuries old principles of physics. The charger, also known as the transmitter, contains a metallic coil which generates a magnetic field when electricity runs through it. The receiver in the device that needs charging, collects this magnetic energy and converts it into electricity and the device gets charged. The wireless charger developed by Resonant is based on patented technology on the same principles and is able to charge devices faster and more efficiently, sometimes ten times faster than the currently used technologies, the founders claim. 

The company’s technology emits less heat than competitors’ wireless chargers, which helps the device to fit within the FDA’s requirements, Zulauf says. That’s important, he adds, because any implanted device that creates too much heat can cause the tissues around it to burn. 

The startup is already working with device manufacturers to develop wireless charging compatible devices and working with them to seek FDA clearances. While patients with pacemakers will still need to visit a medical facility to recharge batteries compatible with Resonant chargers, patients with implanted devices such as spinal cord and deep brain stimulators could charge them at home within two hours, Zulauf says. 

The funds from this round will go towards partnering with more medical device manufacturers. “Our mission is to get rid of these extra battery replacement surgeries and get rid of drive lines forever. The funding will be used to scale our medical business in pursuit of that mission,” says Zulauf.

Orin Hoffman, the partner at The Engine, who led the funding says people have tried to make an efficient wireless charging device for years but haven’t found major success. He recalls that the first time he saw the Resonant technology and the data presented by the founders he said, “Where were you 15 years ago?”  He believes that the company's wireless chargers will significantly improve patients’ quality of life. “Having a tube that goes from inside your body out your stomach to charge these devices, you can imagine, is pretty horrific life experience,”

While the founders want their chargers to revolutionize charging of medical devices, that’s not the limit of its technology. In the coming years, the company also wants to pursue Zulauf’s original vision of developing faster chargers for electric vehicles.. “We want to be a company that's pushing upward in the medical and electric vehicle space,” says Zulauf.