INVESTIGATIONS are underway after a fire broke out at Rivian Automotive’s production facility in Normal, Illinois recently.
The fire, which was caused by the thermal runaway of a defective battery pack inside the manufacturer’s battery test centre, occurred on the morning of 28 May and led to the evacuation of the southwest side of the building.
It is understood the battery pack that caused the incident was in the repair area of the division at the time.
According to a report published in Automotive News, the battery pack was already identified as faulty prior to the fire and Rivian is investigating the cause of the defect.
“No injuries occurred during the event, and production has restarted,” a Rivian spokesperson told the publication.
“Every one of our batteries undergoes a rigorous and comprehensive testing regime before being certified for installation in our vehicles.
“We evacuated a portion of the plant facility as standard practice during a thermal event on Saturday. Everyone is safe and accounted for and our Environmental, Health and Safety team is investigating the cause (of the fire) with our engineering team and the Normal Fire Department.”
The size and ferocity of the fire saw brigades from Normal and nearby Bloomington assist in containing the blaze.
Once controlled, firefighters connected hoses to the extinguished battery pack and then continued to flow water on the pack to keep it cool to prevent further thermal runaway from occurring.
A thermal runaway occurs when a battery cell overheats and ignites due to an electrical fault or fire. The ignited cell releases more heat to the adjacent cells in a self-sustaining chain reaction.
The fire-damaged pack was moved outdoors, and smoke was ventilated from the building. Only damage to the battery pack and test-booth equipment was reported.
According to a report published in Electek, Rivian produced 2553 electric vehicles and delivered 1227 of them last quarter. The electric-vehicle manufacturer is said to be “losing a lot of money on those vehicles” and “is in a race to continue increasing production to satisfy demand while trying to improve its gross margin”.
A recent article published by Teslarati said that in its fourth quarter (2021) and full-year shareholders letter, Rivian stated that it was developing a new range of battery packs that included high nickel and lithium iron phosphate compositions.
“The scale of our impact is ultimately tied to our ability to deliver compelling unit economincs,” the statement read.
“Beyond extensive continuous improvement activities across the vehicles, we look forward to introducing our new lithium iron phosphate (LFP) battery, updated electronics, and a single-motor drive unit known as Enduro, that we plan to use on both the EDV for single-motor application and the R1 for a dual-motor application.”
It is unknown whether the new chemistry type battery was the same as that involved in the Saturday fire.