[ad#post_ad]We learned that GM has been testing several Chevy Volt preproduction vehicles in extreme winter conditions in Kapuskasing Ontario, where temperatures have been ranging from minus 40 to minus 5 degrees Celsius in winter.
Teams have actually been up there for several months looking at performance both from a battery and range perspective, as well as durability and control on snowy roads.
Voltec engineer Pam Fletcher and Volt chief engineer Andre Farah took some questions from the web, and offered some video responses. Some interesting facts were learned.
GM has long stated they intend for the Volt to obtain up to 40 miles of electric range in most driving circumstances. Though Bob Lutz recently told reporters he only got 28 miles of winter range with his driving behavior, the Volt team insists longer cold-weather ranges would be possible.
Farah notes that even in very cold winter temperatures its still possible to hit 40 miles of EV range, and says ranges “anywhere from from 32 to 40 without difficulty” are likely depending on drivers preferences for cabin heating. Accessory electric draw for cabin heating, and excessive power demands from aggressive driving style will reduce range.
It is well known that lithium ion batteries tend to lose power in cold temperatures. Sub-optimally managed batteries in some electric cars, like the MINI E, experience a drop in acceleration and top speed performance in very cold weather. According to Fletcher and Farah this will not be the case in the Volt. They state there will be no loss of power in cold temperature, and that the car is designed to achieve the same specs in EV mode and range extended mode across the entire temperature spectrum.
An advantage the Volt has over pure EVs is that when its very cold, the batteries can be heated using the gas generator. If the car is plugged in it will condition the battery using grid energy, if it is not, and its very cold, 30 degrees below 0, the generator will go on at the outset. Cabin temperature can be pre-programmed or set via mobile phone app to warm the car using grid energy as well.
Farah stated he learned that if that cars were soaked in the cold temperatures outside overnight, the batteries did not drop fully to the outdoor temperature.
He also noted that from a very cold start after the ICE goes on to warm the battery, roughly within 3 miles it will be warm enough to allow the engine to turn off.
It was also mentioned that cold temperature operation is not expected to reduce battery longevity. Farah said heat will have a negative impact on battery life, the extent of which Farah said GM is still determining “exactly what that is,” because its hard to test longevity versus temperature using laboratory models.
They noted Volt snow traction is very successful, though Farah was able to get one Volt stuck with severe “limit case testing” on a snowy road. It had to be towed. These limit cases are what the engineers test, but Farah indicates these are not scenarios everyday drivers would expect to encounter.
This entry was posted on Tuesday, February 23rd, 2010 at 7:14 am and is filed under Environment. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.