Thermal management of the Williams Advanced Engineering battery was the most significant part of the Malaysian event, as teams struggled to deal with the 39-degree ambient temperature and high humidity.
Williams’s programme leader Gary Ekerold was a man in demand in Putrajaya, with the expected heat management issues strangling even the more fancied teams in the 39-degree ambient conditions.
Renault e.dams drivers Sebastien Buemi and Nicolas Prost were both hit twice during the weekend, effectively halting their championship lead. Nicolas Prost in particular was extremely disappointed and perplexed given the team’s energy management was on target.
“Twice it was a battery issue. I had old-spec batteries on both cars, so they need to explain why” said Prost. “We were saving a lot of energy and still we were overheating so it’s very disappointing. It looked like a really strong race at the beginning and we were looking at a 1-2. Sebastien had the same problem – two battery failures so they have to give us some explanation.”
Ekerold said the confusion from drivers stemmed from the fact that a ‘battery management system’ error message lit up on their dash.
“The error that comes up on the steering wheel is a BMS error that protects the entire system on the car,” said Ekerold. “That could be an error on any aspect and the battery will protect the car.”
But how does that explain Antonio Felix Da Costa’s failure when just within sight of a podium, given that Team Aguri’s Mark Preston was confident heading into the race, saying: “We proved in Bueno Aires that we can manage battery temperature and energy.”
In reality it was neither Williams nor the teams’ fault. With performance ramping up in the second season, the evolution of the power train capacity is already stretching the limits of last year’s battery. Even in the cooler conditions in Beijing, four batteries had to be replaced after Friday’s shakedown, while charger explosion damaged Sam Bird’s battery on before qualifying last weekend.
“The battery was never designed to run at 39 degrees ambient temperature. So we’re already past that operating window” explained Ekerold. “It wasn’t designed to run at 170kW, it was designed to run at 133kW. So we’re already past that operating window. In terms of a fundamental design fault, that’s certainly not the case.”
Ironically, with teams now running their own bespoke powertrains, Williams will be limited on what thermal management solutions it can offer moving forward.
“We can’t share the ultimate level of data with teams because they need to learn this process and understand it themselves” Ekerold, added.
One thing the thermal dilemma has done is spice up a season that looked to be a forgone conclusion at round one.
Feeling the heat
Images: FIA Formula E