The incident occurred on Tuesday afternoon in the garage of battery supplier WAE (formerly known as Williams Advanced Engineering) at the Circuit Ricardo Tormo in Spain.
Running was postponed at the test indefinitely while a full investigation was undertaken by the FIA and WAE, before the governing body confirmed that testing could resume on Thursday afternoon.
The FIA has since revealed further details about the incident which occurred when the DS Penske of Robert Shwartzman came to a stop on track during Tuesday morning’s opening three-hour session.
The automatic battery safety system was triggered in the car causing it to stop with the red light visible as per safety protocol, before it was taken back to the pits, where the battery was removed and taken to WAE.
The FIA stated that “while being manually inspected by the battery single supplier team, there was an arc flash and some sparking, that resulted in a localised fire”.
The blaze caused damage to the garages of WAE and Mahindra, the team forced to run only one car for the remainder of the test, while one person was taken to hospital for precautionary checks before being released.
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The FIA confirmed that all the batteries used by teams had been checked, and that “none of the batteries present the same type of symptoms as the unit that failed”.
The FIA statement continued: “The investigations and findings provided by the single supplier of batteries for Formula E cars and reviewed by the FIA confirm that use of the battery packs in line with the single supplier’s recommendations and requirements are within acceptable safety tolerances for a motorsport environment and therefore acceptable for on-track activity to go ahead.
“The single supplier of batteries for Formula E cars has assessed available data for all batteries and confirmed that none of the batteries present the same type of symptoms as the unit that failed. The batteries are of the same specification as used in all twenty-two cars and sixteen races last season.”
A four-and-a-half-hour session was held on Thursday afternoon following the investigation with 10 hours of running due to take place on Friday at the circuit.
A race simulation took place this morning, which was headed by Robin Frijns, but further safety measures have been put in place to prevent any further issues. This included only a simulation of the fast-charging pitstops which are due to be introduced this season, while drivers were limited to 300kW of power.
The FIA added: “In addition to the normal monitoring, and to mitigate risks, a series of additional safety measures have been introduced including reducing the power output to 300kW and investigating with immediate effect any potential issue or similar occurrence.”
