Williams Advanced Engineering was the sole supplier of the battery system for the entire Formula E grid since the fully-electric FIA racing series began in 2014 to the end of season 4 in 2018. The company's battery expertise originated from Formula One, following the introduction of KERS – including new batteries and battery management systems – into the sport in 2009. The challenge has been significant. The Formula E battery has to propel cars to speeds of up to 225kph, yet still be practical in terms of safety, aerodynamics, range and recharging times.
And safety is at its core; it is the first lithium-ion battery to have passed stringent FIA crash testing regulations and met stringent air safety regulations in order to be transported around the world to support the global race calendar.
Over four seasons, there have been only two on-track failures and the equivalent of more than 1,000 cars have raced using the battery since the championship started, representing a success rate of more than 99.5 percent. The total distance travelled by Williams-supplied Formula E batteries is 240,000miles – the same as a trip from the Earth to the Moon.
In 2018, Williams Advanced Engineering received the Queen's Award for Enterprise in Innovation for its ability to design, develop and deliver the batteries for all Formula E cars racing in the championship while ensuring the successful transfer of that knowledge to road cars and other forms of sustainable transport outside of the all-electric racing series. Also in 2018 the company was named as the sole supplier of batteries for the electrification of the World Rallycross Championship in 2020.