Testing at the Circuit Ricardo Tormo in Spain was postponed following a battery fire in the garage of battery supplier WAE (formerly known as Williams Advanced Engineering) on Tuesday afternoon.
Following an investigation by the FIA and WAE, which concluded that “none of the [other] batteries present the same type of symptoms as the unit that failed”, testing resumed on Thursday afternoon and across Friday with no issues.
Di Grassi, who has returned to the Abt Cupra team this season, praised the reaction to the incident by emergency crews as well as the FIA for updating drivers on the ongoing situation.
“I was very relaxed about what happened to be honest,” he told Autosport.
“I think the track record of Formula E having one battery fire in 10 years of existence, it's amazing.
“It's much better than any combustion racing series had in the past, including Formula 1. So I think that's not a problem at all having one event like this.
“The reaction from Formula E, it was amazing. In 20 minutes, everything was concealed, everyone was evacuated, the fire was contained, it didn't spread out.
Source: Autosport