Vauxhall owner Stellantis has said it will invest more than €30bn (£26bn) in electric vehicles between now and the end of 2021
It aims to make the total cost of owning an electric vehicle equal to that of a petrol-driven model by 2026.
Stellantis said it would build at least five battery plants in Europe and the US to support its strategy.
It has already announced two plants in France and Germany, and the third will be in Italy in Termoli.
The world's fourth-biggest car maker, which was formed in January from the merger of Italian-American firm Fiat Chrysler and France's PSA, is gearing up to compete with electric vehicle leader Tesla and other big car manufacturers.
Stellantis said that all 14 of its vehicle brands, which include Peugeot, Jeep, Ram, Fiat and Opel, will start selling fully electrified vehicles.
The company said it wanted to focus on keeping the vehicles affordable and sustainable. However, a spokesman declined to indicate what sort of prices Stellantis intended to charge for passenger cars.
It will also electrify its commercial vehicle line-up, and roll out hydrogen fuel-cell vans by the end of 2021.
"This transformation period is a wonderful opportunity to reset the clock and start a new race," Stellantis chief executive Carlos Tavares said. "The group is at full speed on its electrification journey."
The company said its electric cars would be built on four platforms, have driving ranges of 500 to 800 km (300 to 500 miles) on a single charge, and fast-charging capability of 32 km (20 miles) per minute.
The £100m investment, to which the UK government will contribute about £30m, will safeguard more than 1,000 factory jobs.
The future of the plant had been in doubt after Stellantis scrapped plans to build its new Astra model there.
Stellantis is currently building two battery plants, one in France and one in Germany, and it said it would establish a third at Termoli in Italy.
The two "gigafactories" at Douvrin in France and Kaiserslautern in Germany will get French and German government support of €1.3bn (£1.1bn).
A spokesman said Stellantis would build at least two more such plants, which are likely to be in the US.
He add that the company planned to build the battery factories at its major production hubs, and did not have current plans to build any gigafactories in the UK.