Mercedes confirms findings after initial investigation into ‘catastrophic’ Russell DNF

James Allison, the Mercedes technical director, has revealed that “heat damage” contributed to George Russell’s “catastrophic” battery failure at the Canadian Grand Prix.

Russell recorded his first retirement of the F1 2026 season in Montreal, where he came to a halt after 29 laps to bring an end to his thrilling battle with teammate Kimi Antonelli.

Mercedes: George Russell battery suffered ‘heat damage’

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Antonelli went on to record his fourth victory in succession, extending his lead over Russell to 43 points after five races.

Russell claimed after the race that the title is now Antonelli’s “to lose” given the teenager’s commanding advantage at this stage of the season.

In a clip released by Mercedes, Allison has confirmed that a “catastrophic” battery failure resulted in an “engine kill.”

And he revealed that an initial investigation has found that the battery was in a “fairly unhappy” state having suffered heat damage prior to the failure.

Allison explained: “It was a big weekend for us. Key because it was the weekend where we introduced our first major upgrade for the year.

“We were looking for it to be strong. It was.

“But a weekend that was otherwise extremely good from a performance point of view was marred by the disappointment we all feel for letting George down with the reliability of the car.

“On George’s PU failure, it was an engine kill caused by a failure in the battery, which just suffered a catastrophic failure a third of the way into the race and brought George’s race to an end.

“We could see enough at the end of the race that the battery was fairly unhappy, some heat damage there, and we’ll have to figure out in the coming days and weeks exactly what caused that and put it right.”

George Russell vs Kimi Antonelli: Mercedes head-to-head stats for F1 2026 season

F1 2026: Head-to-head qualifying statistics between teammates

F1 2026: Head-to-head race statistics between teammates

Russell found himself at the centre of an FIA investigation in Canada for throwing his headrest on to the track in frustration in the immediate aftermath of his retirement.

The 28-year-old was handed a suspended €5,000 fine, with the stewards revealing that Russell had “expressed his embarrassment” and had apologised privately, as well as offering to make a public apology.

In a post to social media on Monday, he wrote: “Apologies to the marshals & FIA for making their job harder than it needed to be. Lots of emotions in the moment.”

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