Nearly a month after the Pickett wildfire began, the cause of the blaze in the hills at the northern end of Napa Valley remains the subject of investigation. Now, lawyers for the winery that owns the property where the blaze may have started have asked state fire investigators to look at another possible cause—a faulty car battery.

Wine Spectator has viewed a letter from attorneys representing Hundred Acre Wines to CalFire, the state fire agency, asking investigators to examine a damaged battery inside a trailer on Hundred Acre’s property, near where the fire is believed to have started.

The letter says there is evidence of a faulty terminal on the battery and asks CalFire’s investigators to look into whether electricity from that terminal could have started a blaze. Wine Spectator has the full story.