A Silicon Valley-based battery tech startup claims to have created a solid-state EV battery that can allow an electric vehicle to cover 400 miles and then charge from 10 to 80% in just 15 minutes.

As soon as 2024, the company says the technology will be deployed in mainstream cars, bringing EV charging closer to the convenience of filling up a gas tank.

Critics say we should not take those claims at face value. The drawbacks of solid-state batteries include the fact that they don't rely on the conventional mix of chemicals used in alithium-ion battery.

Solid-state batteries are more stable and less prone to catching on fire than their Li-ion counterparts, according to proponents. It's possible to cram more energy into the same amount of space while also allowing drivers to charge their cars faster.

Some of the prototype batteries were able to discharge and charge over 1000 times.

"Traditional lithium-ion cells, or any other solid-state effort to date, couldn't even come close to that," Asim Hussain said.

There are many drawbacks to the technology. Despite billions of dollars in investment by Nissan and Toyota, the production of these batteries at a mass-manufacturing scale is proving difficult.

Not everyone is convinced that we are just two years away from reliable solid-state batteries for electric vehicles.

There are challenges with how you translate energy density demonstrated in a research laboratory cell to a larger cell for practical applications, according to a researcher. Physical limits to energy density exist.

Solid-state batteries need to breathe in order to expand. In a lab, it's hard to control that pressure.

There is a chance of an explosion if you move away from the batteries.

"We are doubling the energy density which means that the energy is very high, just like a bomb for example," Nissan's battery strategy group lead said.

Solid-state batteries are believed to be the future of the electric vehicle, as they promise longer ranges and faster recharging times. The technology is still in its infancy, and a lot of work needs to be done before we can ditch the batteries.

Scientists say a revolutionary solid-state battery is close to being ready.

Toyota made an electric car with a game-changing solid state battery.