Nuclear Batteries: Energy Storage for Decades

In 1970, surgeons in Paris implanted the first nuclear-powered pacemaker, and over the next five years, at least 1,400 additional people received the devices, mostly in France and the United States. Encased in titanium, the batteries for these devices contained a radioactive isotope—typically about a tenth of a gram of plutonium-238—and could operate for decades without maintenance. The invention provided relief to a population of people who previously needed surgery every few years to change out their pacemaker’s chemical battery.

As time went on, though, the whereabouts of these radioactive tickers became increasingly difficult to track. In the United States, the devices were supposed to be returned to the U.S. Department of Energy for plutonium recovery. But often, that didn’t happen. Doctors changed jobs, manufacturers went out of business, patients died, and families forgot about their loved one’s pacemaker. Too often, the radioactive material landed in crematoriums and coffins.

Uncomfortable with the situation, regulators worldwide nixed the devices. The last known nuclear-powered pacemaker was implanted in 1988. After that, aside from a few specialty uses, such as deep-space probes and Siberian lighthouses, development and deployment of nuclear batteries effectively came to a halt.

Medtronic’s 1970 Laurens-Alcatel pulse generator powered pacemakers with plutonium-238. Smith Collection/Getty Images

Technology never truly dies, and nuclear batteries are no exception. Research grew active again after 2000, although it lacked commercial translation. But over the last year, a host of companies and research groups around the world have announced advances that they say will invigorate the technology and extend its use to robots, drones, sensors, and solar farms, as well as spacecraft and biomedical implants.

The new groups are employing modern, more-exotic technology that goes beyond the designs of the past, allowing them to pursue the finest nuclear batteries ever made. As with the first generation, the allure of nuclear batteries is still their extraordinarily long life-spans: several decades and, with proper fuel choice, possibly centuries. They could also deliver more energy in packages that weigh less than those of chemical batteries.

The question is, who’s going to buy them? I’ve been involved in this sector for nearly 40 years as a nuclear engineer, professor, and consultant. Here’s what I’ve observed: The technology works, it has many advantages over chemical batteries, and it can be utilized safely. But what very few companies have been able to do is find a new market for these batteries and make a product that has an impact. Part of the problem is that there is no good solution to the need to track these sources and make sure they are disposed of properly at the end of the battery’s life.

There are more companies working out the challenges now than I’ve ever seen in my career, and that’s good for the field—it…