GM Plugs Its Chevy Volt Hybrid, but Will It Be Road-Ready In Time?
It's the battery, stupid...
GM Plugs Its Chevy Volt Hybrid, but Will It Be Road-Ready In Time?
- SPEED RACER: The Chaparral Volt racer is GM West Coast Advanced Design Studio's concept vehicle entry in the 2008 Los Angeles Auto Show Design Challenge competition. The concept design was created for the 2025 revival of the Los Angeles Times Grand Prix, which is to address clean, renewable and abundant California resources. The design proposes using advanced extended-range EV propulsion systems as well as innovative energy collection, generation and management technology to enable greener car racing. Courtesy of GM
- HIGH VOLTAGE: Bob Lutz, GM vice chairman of Global Product Development and an early proponent of the Chevy Volt program, recently drove one of the 25 to 30 Volt engineering "mules" now under intense evaluation at the company's Milford, Mich., proving grounds. Engineers have installed the prototype E-Flex propulsion system in GM's future global compact car architecture for development and testing. Joining Lutz [left] was [from left to right] Bob Kruse, GM executive director, Global Vehicle Systems and Integration; Jon Lauckner, vice president Global Program Management; and Andrew Farah, Volt vehicle chief engineer. Courtesy of GM
- TRANSMISSION TUNNEL: A General Motors battery engineer positions a prototype E-Flex battery pack for loading into a test vehicle at the GM battery lab. The T-shaped battery pack is buried deep inside the vehicle—in the center "transmission tunnel" and below the rear seat—to improve safety in collisions. Courtesy of GM
- TEMPERATURE TESTING: General Motors battery lab engineers prepare a prototype battery pack for the Chevy Volt for testing in the thermal chamber. The specialists are working to better understand how temperature changes affect battery performance over time. The Volt battery is expected to last 10 years, or 150,000 miles (240,000 kilometers), of travel. Courtesy of GM
- POWER SOURCE: Each lithium-based cell in the Volt's battery pack is enclosed in a flat, laminated aluminum film pouch that is about half the size of a legal notebook pad. Inside, a liquid electrolyte bathes sheetlike positive and negative electrodes, which are separated by a permeable membrane. The two tabs at the top of the pouch are the cell's electrical contacts. Liquid cooling keeps the 250-cell battery pack from heating too much, prematurely aging the cells. Should a single cell fail, the pack fails, so cell manufacture requires near flawless quality controls. Courtesy of GM
- BEEFIER BATTERY: The Volt's T-shaped battery pack, which contains 250 lithium-based cells, is considerably smaller than the similarly configured lead–acid battery pack that powered GM's EV-1 electric vehicle. This side-by-side comparison took place at the GM Technical Center's battery development lab in Warren, Mich. The first EVs (electric vehicles) were powered by lead–acid batteries, then came nickel–metal hydride types which are now found in most hybrid vehicles. Lithium ion batteries, which power cell phones and laptops, have evolved into other lithium-based chemistries that are better suited for automotive use. Courtesy of GM
- WHAT A DRAG: Volt designers and engineers are working to maximize the car's battery-only range by reducing losses that rob the system of power. For example, intense digital simulation and 700 hours of wind tunnel tests have given the Volt the best aerodynamic drag coefficient ever for a GM car—except, that is, for the Volt's forebear, the company's ill-fated EV-1 battery-electric vehicle. The Volt's tires, which are recessed into the wheel wells to cut drag, are designed to offer less frictional resistance to rolling than do conventional tires, which further adds range. Courtesy of GM
- ECLECTIC ELECTRIC: General Motors engineers built the Chevy Volt on a flat chassis that contains an electric drive unit (front, driver side), an engine generator (front, passenger side) and a 16-kilowatt, lithium-based battery pack that is shaped like a "T". GM says that the Volt is only the first of several future models that will share its front-wheel, transverse drive configuration. Its E-Flex platform features an electrically driven drive train and creates electricity on board with a generator set or, potentially, a hydrogen fuel cell. Regenerative brakes, which recapture stopping energy, will also contribute to the on-board power supply. Courtesy of GM
- CHARGING INTO THE FUTURE: Each night, Chevrolet Volt owners will be expected to recharge their car batteries with cheap, off-peak utility power from an electric socket. GM engineers estimate that fully recharging the 400-pound (180-kilogram) battery pack will take less than three hours using a 220-volt outlet or under eight hours using a typical 110-volt household outlet. For extended trips, the gas engine generates onboard power, thereby avoiding the "range anxiety" that can strike drivers of battery-only vehicles. The charge port sits on the side just behind the front passenger-side wheel. Courtesy of GM
- ELECTRIC CAR: The Chevrolet Volt "extended-range electric vehicle" embodies General Motors's efforts to leapfrog current gas-electric hybrid car technology to something that's even greener. The 2011 Chevy Volt production show car is the latest iteration of the evolving design. The hybrid vehicle recharges its lithium-based battery with energy generated by a four-cylinder gasoline engine only after about 40 miles (65 kilometers)—the distance of most average daily commutes. The car reportedly will sell for $35,000 or more. Courtesy of GM
