The battery pack that will be used in the new Pure ETCR electric touring car series has been unveiled, having been designed and produced by Williams Advanced Engineering in only seven months.
Williams drew on its extensive experience of electric powertrains in the design of the pack, the subsidiary of the Williams Formula 1 team having been the sole supplier of batteries to the Formula E electric single seater series from its inception in 2014 until the end of the 2018 season.
The 798V pack will produce peak power of 500kW and 300kW continuous power with a 62kWh capacity. Four push-to-pass activations will be possible per the 21-minute maximum race distance as per the series regulations.
The pack will be rechargeable from 10% to 90% power at 60kWh in less than one hour – ETCR intends its cars to be recharged at an ‘Energy Station’, which will form the centerpiece of a fanzone in the paddock, powered by hydrogen fuel cell technology.
The bespoke ETCR battery pack was designed in-house at Williams, combining its motorsport-designed Vehicle Control Module with a dual ARM Cortex-A9 processor and the Field-Programmable Gate Array (FPGA).
The battery cells are encased in a composite structure that has been designed to provide an electrical barrier against electromagnetic current and survive a 50g crash simulation. CFD thermal analysis at both cell and pack level recorded the thermal characteristics of the battery pack so that its cooling and weight efficiency could be optimized.
Williams Advanced Engineering began the battery project in May 2019 after being appointed battery supplier to ETCR. Two months later, cell and prototype module tests were underway and by September 2019 extensive CFD and FEA simulations were being carried out. Manufacture began in December, followed by physical testing to replicate a full race season.
All-electrical testing was completed at the Williams site in Grove, Oxfordshire, using one of the largest Kratzer and AV900 simulators in the UK. Every battery manufactured for the series will be put through end-of-line trials to verify its production build quality.
The Pure ETCR series is scheduled to make its public debut on July 9-12, 2020, with a time trial at the Goodwood Festival Of Speed, followed by a promotional round supporting the FIA WTCR at Salzburgring, Austria, on July 26-28.