Gosh, it looks like one of the car world’s long-promised, perma-delayed technology leaps has finally arrived: the solid-state battery, or SSB. It comes from Donut Lab, the Finnish company best known for in-wheel electric motors. Those motors feature in Verge electric motorbikes (with the hubless rear wheel). Order a Verge bike today, and you’ll get one with a SSB.
Quick recap. A standard battery consists of cells made up of two electrodes, one containing lithium, the other graphite. Between them is a gel electrolyte and a separator membrane. A solid-state cell has no gel, and generally uses a solid ceramic separator. Advantages are huge. First, it’s basically fire-resistant, and it also maintains its performance between about minus 30 and plus 90ºC.
That means the battery needs less of the bulky heavy structures and cooling channels, so it can be lighter and smaller for a given capacity. Also, a conventional battery’s charge speed limit stems from the need to keep it cool while charging. The solid-state job can be run hotter, so can be charged faster.
Donut says zero to 90 per cent in five mins, on a high-power charge post. That’s petrol-car fast. It also claims an energy density of 400Wh/kg. Multiply that up and you have an 80kWh pack at just 200kg. About the same as a 300bhp engine and gearbox. Another striking claim: durability. It’s said to be good for 5,000 cycles. In a 300-mile EV, that’d be 1.5 million miles. So, lighter, smaller, faster to charge, safer, and more durable.
Similar claims are being made for VW’s QuantumScape and Rimac’s ProLogium cells, as well as Toyota’s and Nissan’s. But none of those are claiming production before 2028.
What makes the Donut Lab announcement so exciting, if it can realise it, is cost. It says its SSB will actually be less than a conventional lithium-ion battery. It doesn’t use scarce minerals that are mined and processed in potentially hostile states. Rather, it’s made of easily obtained substances, though for the moment it’s being mysterious as to what those are.
No-one says SSBs will take over immediately. Lithium-ion batteries, especially with LFP chemistry are still getting cheaper, and the world has a lot of factories to make them, but this does look like a real breakthrough.
