Successfully commercializing solid-state battery technology could be key to making electric battery cars as affordable as today's gasoline cars. Experts say this means the cost of producing a kilowatt hour of electricity needs to fall to around $100 from a little under $200/kWh today.

Global automakers are racing to lower battery manufacturing costs to pad out today's thin margins on battery cars.

"We see this tipping point around 2025," says Nissan Motor Co 7210.T Executive Vice President Daniele Schillaci.

"By then, for the customer, it will be practically the same cost to buy petrol or EV. If you have the same price for EVs and petrol, why would you buy traditional technology?"