xcel
04-03-2008, 01:54 PM
Volt’s finalized design is shaping up. (http://www.cleanmpg.com/forums/showthread.php?p=82916)
http://www.cleanmpg.com/photos/data/501/Continental_A123Systems_-_Compact_Power_LG_ChemLi-Ion_packs_side_by_side.jpgWayne Gerdes - CleanMPG (www.cleanmpg.com) - April 3, 2008
Continental-A123Systems and Compact Power-LG Chem Li-Ion's in an intermediate configuration side by side on the test stand.
WARREN, MI. - Engineers at GM’s battery test facilities have developed a new computer algorithm to accelerate durability testing of the advanced lithium-ion batteries needed to power the Chevrolet Volt for up to 40 miles of AER (all-electric range).
This advanced computer program duplicates real-life vehicle speed and cargo-carrying conditions, and compresses 10 years of comprehensive battery testing into the Volt’s short development schedule.
The battery cycling equipment is used around the clock in GM test facilities in Warren, Mich. and Mainz-Kastel, Germany. It charges and discharges power from the prototype batteries based on the Volt’s approximately 40-mile AER. Results from the test data will help model the long-term durability of the Volts Li-Ion battery.
“Production timing of the Volt is directly related to our ability to predict how this battery will perform over the life of the vehicle. The challenge is predicting 10 years of battery life with just over two years of testing time,” said Frank Weber, global vehicle chief engineer, Chevrolet Volt and E-Flex systems. “The battery team is able to utilize human and technical resources around the globe to reduce testing time.”
Testing the batteries in the laboratory provides a predictable environment but will soon be integrated into “mules,” or test vehicles for on-road testing.
Engineering
The battery is roughly 6 feet long and weighs more than 375 pounds. The T-shaped battery will be located down the center tunnel of the vehicle and under the rear seats. This integration requires the battery to be treated as part of the vehicle structure. Simulation data also indicates that the center placement provides greater protection to the battery.
Notice the similarity between the Volt’s T-shaped Li-Ion pack design and the T-shaped NiMH (or original Pb-Acid) pack in the EV1?
http://www.cleanmpg.com/photos/data/506/Resize_of_GM_EV1_Propulsion_Drawing.jpg
GM EV1 underpinnings
Engineering innovations are also required to maximize the Volt’s 40-mile electric-only range and minimize the use of its range-extending internal combustion engine. To reduce mass, the Volt is being engineered with a relatively small fuel tank. This reduces weight and provides us with a look into the first major spec change from the original. Only 400 + miles between fill-ups vs. 600 miles previously so expect a 7 gallon tank.
Interior
The battery pushed the occupants outboard, or to the sides of the vehicle, so the design team had to get creative with the sections of the roof structure to enable aerodynamics and provide adequate head room. The interior will accommodate a 6-foot 2-inch (a 99th percentile) male comfortably in both the front and rear seats.
Reducing drag
Aerodynamic drag, or wind resistance, accounts for about 20 percent of the energy consumed by an average vehicle, directly reducing fuel efficiency.
Aerodynamics development began with a 1/3-scale model where basic shape and major features are defined. The model includes a highly detailed underbody and engine compartment. Radiator and under-hood cooling flow are developed with computational fluid dynamic models. Development continues with full-scale models, where shape is refined and optimized for low wind noise. The development process concludes with a vehicle prototype validation of the math-based analysis and physical testing.
“After extensive aerodynamic testing of the Volt, the vehicle now has a coefficient of drag that is 30 percent lower than the original concept,” said Ed Welburn, GM vice president, Global Design. “It’s not easy, but it is a necessity.”
http://www.cleanmpg.com/photos/data/2/VOLT_EREV_operations_modes.jpg
Basic VOLT EREV operations modes.
http://www.cleanmpg.com/photos/data/501/Continental_A123Systems_-_Compact_Power_LG_ChemLi-Ion_packs_side_by_side.jpgWayne Gerdes - CleanMPG (www.cleanmpg.com) - April 3, 2008
Continental-A123Systems and Compact Power-LG Chem Li-Ion's in an intermediate configuration side by side on the test stand.
WARREN, MI. - Engineers at GM’s battery test facilities have developed a new computer algorithm to accelerate durability testing of the advanced lithium-ion batteries needed to power the Chevrolet Volt for up to 40 miles of AER (all-electric range).
This advanced computer program duplicates real-life vehicle speed and cargo-carrying conditions, and compresses 10 years of comprehensive battery testing into the Volt’s short development schedule.
The battery cycling equipment is used around the clock in GM test facilities in Warren, Mich. and Mainz-Kastel, Germany. It charges and discharges power from the prototype batteries based on the Volt’s approximately 40-mile AER. Results from the test data will help model the long-term durability of the Volts Li-Ion battery.
“Production timing of the Volt is directly related to our ability to predict how this battery will perform over the life of the vehicle. The challenge is predicting 10 years of battery life with just over two years of testing time,” said Frank Weber, global vehicle chief engineer, Chevrolet Volt and E-Flex systems. “The battery team is able to utilize human and technical resources around the globe to reduce testing time.”
Testing the batteries in the laboratory provides a predictable environment but will soon be integrated into “mules,” or test vehicles for on-road testing.
Engineering
The battery is roughly 6 feet long and weighs more than 375 pounds. The T-shaped battery will be located down the center tunnel of the vehicle and under the rear seats. This integration requires the battery to be treated as part of the vehicle structure. Simulation data also indicates that the center placement provides greater protection to the battery.
Notice the similarity between the Volt’s T-shaped Li-Ion pack design and the T-shaped NiMH (or original Pb-Acid) pack in the EV1?
http://www.cleanmpg.com/photos/data/506/Resize_of_GM_EV1_Propulsion_Drawing.jpg
GM EV1 underpinnings
Engineering innovations are also required to maximize the Volt’s 40-mile electric-only range and minimize the use of its range-extending internal combustion engine. To reduce mass, the Volt is being engineered with a relatively small fuel tank. This reduces weight and provides us with a look into the first major spec change from the original. Only 400 + miles between fill-ups vs. 600 miles previously so expect a 7 gallon tank.
Interior
The battery pushed the occupants outboard, or to the sides of the vehicle, so the design team had to get creative with the sections of the roof structure to enable aerodynamics and provide adequate head room. The interior will accommodate a 6-foot 2-inch (a 99th percentile) male comfortably in both the front and rear seats.
Reducing drag
Aerodynamic drag, or wind resistance, accounts for about 20 percent of the energy consumed by an average vehicle, directly reducing fuel efficiency.
Aerodynamics development began with a 1/3-scale model where basic shape and major features are defined. The model includes a highly detailed underbody and engine compartment. Radiator and under-hood cooling flow are developed with computational fluid dynamic models. Development continues with full-scale models, where shape is refined and optimized for low wind noise. The development process concludes with a vehicle prototype validation of the math-based analysis and physical testing.
“After extensive aerodynamic testing of the Volt, the vehicle now has a coefficient of drag that is 30 percent lower than the original concept,” said Ed Welburn, GM vice president, Global Design. “It’s not easy, but it is a necessity.”
http://www.cleanmpg.com/photos/data/2/VOLT_EREV_operations_modes.jpg
Basic VOLT EREV operations modes.