A solid-state battery is a battery technology that uses solid electrodes and a solid electrolyte, instead of the liquid or polymer gel electrolytes found in lithium-ion or lithium polymer batteries.
While solid electrolytes were first discovered in the 19th century, several drawbacks, such as low energy densities, have prevented widespread application. Developments in the late 20th and early 21st century have caused renewed interest in solid-state battery technologies, especially in the context of electric vehicles, starting in the 2010s.
Materials proposed for use as solid electrolytes in solid-state batteries include ceramics (e.g., oxides, sulfides, phosphates), and solid polymers. Solid-state batteries have found use in pacemakers, RFID and wearable devices. They are potentially safer, with higher energy densities, but at a much higher cost. Challenges to widespread adoption include energy and power density, durability, material costs, sensitivity and stability.
A solid-state battery is a rechargeable energy storage system similar in overall structure and operation to the more familiar lithium-ion battery. The two differ in that a lithium-ion battery contains a liquid electrolyte while a solid-state battery—as its name suggests—features a solid one. This allows solid-state batteries to be lighter, have more energy density, offer more range, and recharge faster. The challenge to making solid-state batteries viable is developing technology commonly used in small devices and applying it to large-scale applications like electric vehicles (EVs).
TOKYO/OSAKA -- In the race to produce the next generation of advanced batteries for electric vehicles, Japan Inc.'s rivals are gathering.
Toyota Motor, the world's biggest car producer in 2020, has long been considered a front-runner to produce a commercially viable solid-state battery -- which would be more stable and faster to charge than the lithium-ion batteries used today by carmakers from Tesla of the U.S. to China's BYD. Toyota plans to announce a prototype of a car powered by a solid-state battery by the end of the year, seeking to launch a vehicle in the early 2020s.
But Germany's Volkswagen, whose sales narrowly trailed Toyota's in 2020, is at its heels. This year the German carmaker increased its investment in QuantumScape, a U.S. startup aiming to produce a solid-state battery. QuantumScape -- backed by Bill Gates and with a market capitalization of almost $11 billion -- said on May 14 that it and VW would decide this year where to build a pilot line for their joint venture to produce batteries. The aim is to establish a production line by 2024, allowing VW to launch EVs with the batteries the following year.
With electric vehicles established as a key part of global efforts to reach net zero carbon emissions, other automakers are raising their bets on advanced battery technology.