Volkswagen plans to halve the cost of power systems for electric cars over the next decade in a massive investment push that could knock Tesla off its perch. The German giant will build six factories capable of producing 240 gigawatt hours of batteries a year in Europe over the next decade. This is enough to provide batteries for 4m cars, equivalent to just over 40pc of Volkswagen Group’s annual vehicle production. Herbert Diess, the VW chief executive, said: “E-mobility has won the race. Our goal is to secure a pole position in the global scaling of batteries.” The plans - estimated to cost about £20bn - means VW will abandon its reliance on external battery suppliers. It is also a definitive statement from the one of the world’s largest automotive companies that electric is the future for transportation. David Bailey, a car industry expert at Birmingham University, said: “VW is ending the uncertainty about whether the future is electric, hybrid, or even hydrogen. This is an industry giant saying electric is the future with massive investment.”