These are independent reviews of the products mentioned, but TIME receives a commission when purchases are made through affiliate links at no additional cost to the purchaser.
It sounds impossible: Just add water to a piece of paper and get energy. Researchers at Empa, a Swiss research institute, devised a proof of concept for a water-activated disposable battery powered by salt (dispersed in the paper) and inks containing graphite, zinc, and carbon. Its voltage, 1.2 volts, is just below what a standard AA alkaline battery offers. Within two to five years, the technology could be used in low-power single-use electronics such as medical diagnostic devices and smart packaging, says Empa’s Gustav Nyström, the inventor. “I see a new role for paper…that could also be an answer to the growing environmental concern over electronic waste,” he says.
More Must-Reads from TIME
- Why Biden Dropped Out
- Ukraine’s Plan to Survive Trump
- The Rise of a New Kind of Parenting Guru
- The Chaos and Commotion of the RNC in Photos
- Why We All Have a Stake in Twisters’ Success
- 8 Eating Habits That Actually Improve Your Sleep
- Welcome to the Noah Lyles Olympics
- Get Our Paris Olympics Newsletter in Your Inbox