BMW will start testing this year a solid-state battery developed in partnership with U.S. battery technology company Solid Power, the automaker said this month.

BMW has been working with Solid Power on a solid-state battery for automotive applications since at least 2017.

In the latest phase of their partnership, BMW will also build prototype versions of Solid Power's battery at its own battery lab near Munich, Germany.

Actual testing of the batteries in a prototype vehicle is scheduled for before 2025. BMW has previously said that a vehicle with solid-state batteries could reach showrooms by around 2030.

Solid Power solid-state battery cell

Solid Power solid-state battery cell

The target date is similar to what other automakers like Nissan and Volkswagen Group are working toward. VW Group has invested in fellow U.S. battery technology company QuantumScape, claiming the firm's battery technology will provide 30% more range and 12-minute charge times. Mercedes-Benz and Hyundai Motor Group have also partnered with a U.S. battery technology company on solid-state batteries, specifically Factorial.

The batteries, which derive their name from their solid electrolytes, promise improved range and shorter charge times compared to current liquid-type batteries, as well as improved safety and lower costs. The main hurdle remains manufacturing the batteries in the high volumes required for automotive applications.

“BMW remains committed to the pursuit of all-solid-state batteries, a technology which we believe has significant potential for the future,” Frank Weber, BMW's head of R&D, said in a statement.

Before it introduces solid-state batteries, BMW will introduce a new lithium-ion battery with a round cell design that promises a 30% improvement in range compared to a current battery of similar size and weight. BMW will introduce it in a family of EVs code-named the Neue Klasse, German for "New Class." The first of the Neue Klasse EVs will arrive in 2025 and will include a sedan in the 3-Series segment and a sporty SUV.