BYD has been running all-electric E6s as taxis in Shenzhen since early 2010, which means there have been over two years of fire-less operations (as far as we know). Apparently, though, on 26 May three people riding in an E6 cab, including the driver, were killed in an accident. China Auto Web calls it "China's first fatal crash involving a high-speed pure-electric car" and notes that Shenzhen traffic police say that a drunk driver crashed a Nissan GT-R traveling at 112 miles per hour into the e6, which quickly caught fire then smashed into a third car, a gas-powered cab. The drunk driver ran from the scene, but later turned himself in. A person in the third car was lightly injured. This version of the story shows that the drunk GT-R driver is at fault, and we await news on if the E6's battery played a role in the fire.
You can see a video report on the incident (in Chinese) below.