A new battery for electric cars that charges in 3 minutes and is 20 years old: “This could change the rules of the game” | Sciences

The technology was developed by Shen Li and colleagues at the Harvard John A. Paulson School of Engineering and Applied Science (SEAS). In 2021, along with William Fitzhugh and Luhan Yi — two students who helped develop the battery — Lee co-founded Adden Energy, a startup headquartered in Waltham, Massachusetts. Their company received the license as well as an additional $5.15 million to build a battery to fit electric vehicles. They want to achieve this within three to five years.

The battery that Harvard researchers developed is a lithium-ion battery, not the lithium-ion battery you find in electric cars around today. Lithium-metal batteries can store more energy at the same volume and recharge in a fraction of the time compared to conventional lithium-ion batteries. The prototype of the new battery did very well in the lab. Recharge speeds reached just three minutes with over 10,000 cycles before running out. “We achieved 5,000 to 10,000 charge cycles in battery life in the lab, compared to 2,000 to 3,000 charge cycles for even the best in class now,” Lee said. “And we don’t see a fundamental limit to scaling our battery technology. This could be a game-changer.”

The design of the battery is inspired by what the Americans call the “BLT sandwich”. These are two slices of bread with toppings in between: bacon (bacon), lettuce (lettuce) and tomatoes (tomatoes). It translates to battery: the bottom slice of the bread is the lithium metal anode, the lettuce is graphite, the tomato layer is the first electrolyte, the bacon layer is the second electrolyte, and the top slice of the bread is the cathode. This complex structure is intended to prevent battery life from being shortened by so-called “bifurcations”. These are small, solid tree-shaped structures to which lithium-metal batteries are sensitive and malfunction.

Existing lithium-ion batteries in electric vehicles become less efficient over time and have a maximum service life of seven to eight years. Replacing the battery with a new one costs so much that drivers often have to buy a new electric car. A new lithium-metal battery could extend the life of electric cars to about 20 years — compared to that of petrol and diesel cars. The battery should not be replaced during this time. This can make a global difference.