Category: GM Volt

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Cadillac ELR Goes Ultrasonic in Pursuit of High Quality

Ultrasonic welding, a high-tech manufacturing process used in the aerospace and medical industries, is helping ensure high quality for the new Cadillac ELR extended-range electric luxury coupe that goes on sale in North America in early 2014.

Ultrasonic welding’s key advantage is exceptional and predictable quality and performance from one battery pack to the next. Every ELR battery, for example, has close to 200 ultrasonic welds. Each is required to meet stringent quality requirements, enabling Cadillac to offer an eight-year/100,000-mile battery system warranty.

Short cycle times, low capital costs and manufacturing flexibility through the use of automation are other advantages of ultrasonic welding.

“Ultrasonic welding is a far superior joining technology in applications where it can be deployed,” said Jay Baron, president and CEO of the Center for Automotive Research in Ann Arbor, Mich. “Cadillac’s innovative process will produce batteries with superior quality compared with traditional methods – and do it more efficiently. This is one example of technology development that is becoming pervasive in today’s world class vehicles.”

General Motors’ Brownstown Battery Assembly plant near Detroit, uses ultrasonic welding to join metal electrode tabs on ELR’s advanced 16.5-kWh lithium-ion battery system, and does it with a proprietary quality monitoring process. Brownstown uses an automated system to execute millions of these welds each year.

Ultrasonic welding uses specialized tools called an anvil and horn to apply rapid mechanical vibrations to the battery’s copper and aluminum electrodes. This creates heat through friction, resulting in a weld that does not require melting-point temperatures or joining material such as adhesives, soldering or fasteners.

An integrated camera vision system is used to shoot a reference image of the weld area prior to the operation to achieve pinpoint accuracy. Quality operators check electrode tabs before and after welding, and the system monitors dozens of signal processing features during each weld.

The battery-specific welding process is a result of collaboration among General Motors’ Manufacturing Systems Research Lab and Advanced Propulsion Center and the Brownstown plant. GM first applied the process on the award-winning Chevrolet Volt – its groundbreaking extended-range electric vehicle – and further refined it for ELR.

“This effort is an outstanding example of teamwork between research and manufacturing engineering,” said Catherine Clegg, GM vice president of Global Manufacturing Engineering. “It has helped integrate the use of highly technical, complex technology into a sustainable manufacturing process, which means we can consistently deliver high-quality batteries to our customers for the Cadillac ELR.”

The ELR’s T-shaped battery pack is located along the centerline of the vehicle, between the front and rear wheels for optimal weight distribution. The 5.5-foot-long (1.6 m), 435-pound (198 kg) pack supplies energy to an advanced electric drive unit capable of 295 lb-ft of instant torque (400 Nm) to propel the vehicle. Using only the energy stored in the battery, the ELR will deliver a GM-estimated range of about 35 miles (56 km) of pure electric driving, depending on terrain, driving techniques and temperature.

Charging the ELR’s battery can be done with a 120V electrical outlet or a dedicated 240V charging station. The vehicle can be completely recharged in about 4.5 hours using a 240V outlet, depending on the outside temperature.

The Cadillac ELR is built at GM’s Detroit-Hamtramck Assembly Plant, one of the few high-volume electric vehicle manufacturing facilities based in the U.S. Its battery pack is built from cell to pack at Brownstown and shipped to Detroit-Hamtramck for assembly into the vehicle.

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Engadget Test Drive the Spark EV [VIDEO]

Engadget got to test drive the The Spark EV, GM's first pure electric car since the company scrapped the EV1 program in 2002.

Performance is quite impressive for an EV this size: it sprints to 60mph in just 7.6 seconds with a top speed of 90mph. The 21kWh nano-phosphate Li-ion battery pack is liquid cooled / heated and is located in the floor. It offers a range of up to 82 miles and takes less than seven hours to fully charge using a level 2 (240V) charging station. Better yet, with a DC fast-charging option coming to the Spark EV later this year, you'll be able to charge the battery to 80% capacity in just 20 minutes.

Chevy's managed to keep the weight down to 2967lbs, which is pretty svelte for a pure electric car. This, combined a low center of gravity and a close to 50/50 weight distribution makes the Spark EV nimble and fun to drive.

Source: Engadget

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Tesla forces GM CEO to consider electric threat

General Motors CEO Dan Akerson has reportedly assigned a team to study the threat posed to the automaker from Tesla, the electric sports sedan maker.

GM’s vice chairman, Steve Girsky disclosed the study in an interview with Bloomberg. “He thinks Tesla could be a big disrupter if we’re not careful,” Bloomberg quoted Girsky as saying.

But the greater threat to GM may be its own corporate culture, notes Forbes contributor Micheline Maynard.

After all, GM “once nurtured, and then killed, a $1 billion program to develop an electric car called the EV1,” Maynard writes. “The issue isn’t what Tesla threatens to do to GM. It’s why GM isn’t a place where such innovations can take place and more importantly, take root,” she added.

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Oak Ridge Lab to develop dynamic wireless EV charging

South Carolina’s leading automotive research center and premier technology and aviation business park have partnered to study next-generation vehicle technology.

The Clemson University International Center for Automotive Research (CU-ICAR) and the S.C. Technology Aviation Center (SCTAC) have contracted with Oak Ridge National Laboratory to support a three-year program to develop and test wireless charging systems for electrical vehicles.

The research is funded by the U.S. Department of Energy.

Wireless Power Transfer Charging (WPTC) of an electric vehicle does not require the use of cables or plugs and could substantially increase convenience — and possibly the number of opportunities — to charge an electric vehicle throughout the daily drive.

For instance, when wireless charging is applied in quasi-dynamic (stop-and-go) or dynamic (vehicle-in-motion) modes, the technology could lead to extended range and downsized batteries for electric vehicles. Such innovations are likely to greatly speed development of electric-powered passenger vehicles by addressing the current technology’s two biggest challenges: range and cost.

CU-ICAR research professor Joachim Taiber, who will lead the project for Clemson, said batteries in next-generation electric-powered vehicles can be made smaller and lighter, greatly increasing the efficiency of power transfer.

“This partnership can advance wireless-charging technology and spark growth in the marketplace because consumers will worry less about range-related issues,” Taiber said.

As part of the project, CU-ICAR and SCTAC researchers will validate the Oak Ridge-developed technology, optimize system design and develop the required communication networks for the wireless charging system.

Testing of the technology will take place at SCTAC and on the Oak Ridge main campus. SCTAC will be a unique, cutting-edge technology demonstration facility and airpark, which currently is home to 85 diverse companies with an international presence in advanced manufacturing, trade, technology and avionics.

“This joint initiative marks the next step in the progression of our strategic partnership with CU-ICAR and multiple private stakeholders in the development of a world-class test track infrastructure to support the rapidly emerging clean transportation ecosystem,” said Jody Bryson, SCTAC president and chief executive officer.

The Oak Ridge National Laboratory charging system will be co-developed and manufactured by Wytheville, Va.-based Evatran. Other project partners include General Motors, Toyota, Duke Energy and Cisco. The value of the subcontract for Clemson University is $1.52 million.

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Plug-In EVs report strong June sales month in US

Electric vehicles had their strongest month in June this year as major automakers cut prices and added hefty incentives to boost sales.

General Motors reported sales jumped by 53 percent to 2,698 in June, up over the 1,760 in June 2012 after it offered incentives worth as much as $5,000 off 2012 models and $4,000 off 2013 models. For the first half of 2013, sales are up 11.8 percent.

Nissan said sales of its all-electric Leaf were up 315 percent over June 2012 to 2,225, for its second-best ever month. Nissan has now sold 9,849 in the first half of 2013, more than the 9,819 it sold in all of 2012. In January, Nissan said it was cutting the price of the entry-level Leaf 18 percent to $28,800 for the 2013 model as it launched U.S. production.

Honda had its best-ever month in June with 208 Fit EVs sold, after selling 83 in the first five months of the year. Honda announced in May that it has cut the monthly lease payment on its Fit EV from $389 to $259 and also is cutting the payment for those who already had leased the vehicle. Honda sold just 93 last year.

Honda started sales in July 2012 of the Fit EV and said it plans to sell just 1,100 over two years, citing capacity constraints. The company has 200 dealers selling the Fit EV and said it plans steadier availability. Honda spokeswoman Jessica Fini said after the lease price was cut, “basically everything on the ground sold,” but she emphasized that the company still has inventory to sell.

GM plans to keep the same incentives in place for at least another month. GM is offering $5,000 off the 2012, and $4,000 off the 2013, and a $269 lease for 36 months with $2,399 due at signing. More than 40 percent of Volts are sold in California, followed by Michigan in second.

Malcho said GM has increased its incentives to stay competitive in the electric vehicle market. The company also wants to clear out some inventory before it begins building 2014 Volts later this summer.

In January, Ford Motor Co. dropped the price of the lease for a Focus EV from about $350 a month to $285, plus $930 due at signing. Ford reduced the base price of the EV Focus by $2,000 to $37,995. But Ford EV sales have remained very modest. Ford sold 157 Focus EVs in May to 723 for the first five months of the year. By contrast Ford has sold 8,177 hybrids in the first five months of the year.

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Cadillac ELR suspension and steering systems in detail [VIDEO]

Drivers expect hybrid and electric cars to have advanced battery and drive systems that make smart use of energy. Cadillac’s upcoming electrified luxury coupe, the 2014 ELR, is designed to exceed those expectations by also providing engaging, responsive driving dynamics enabled by advanced suspension and steering systems.

The technologies include front HiPer Strut suspension, rear compound crank with Watt’s link suspension, a premium ZF electric power steering system and ZF-Sachs continuous damping control.

“ELR’s methodical use of advanced suspension and steering technologies front and rear has resulted in the quiet cabin, agile handling and superior ride that Cadillac customers have come to expect,” said Chris Thomason, ELR vehicle chief engineer. “ELR will redefine for many people what the electric car driving experience is all about. Not only does it make smart use of energy, it makes energy-efficient driving fun and luxurious.”

ELR’s industry-leading Extended-Range Electric Vehicle (EREV) propulsion system delivers 295 lb-ft (400 Nm) of instantly available torque. In driver-selectable Sport mode, the reconfigured accelerator pedal provides quicker torque application and more sensitive feedback through altered suspension and steering settings. ELR also offers Tour, Hold and Mountain driving modes.

With so much torque available, engineers relied on a HiPer Strut front suspension to eliminate torque steer and increase front axle grip while cornering due to optimized tire contact with the road. The HiPer Strut also contributes to ELR’s precise, communicative and linear steering feel, and reduces unwanted steering system disturbances over rough roads and bumps for an overall smoother ride.

In its rear suspension, ELR uses a Watt’s link design to center the car’s rear axle during turns to provide a more balanced driving experience. When cornering, the Watt’s link provides greater lateral stiffness that results in more positive vehicle response to steering inputs and helps keep the rear suspension aligned with the front suspension. When the ELR is traveling on a straightaway, the Watt’s link allows the suspension to travel up and down freely to make the ride more comfortable.

ELR’s premium electric power steering system is designed to provide excellent feedback while saving fuel. The rack-mounted, dual-pinion system – one for steering and one for power assist – consumes energy only when the vehicle is actively steered. A combined electric motor and sensing unit monitors steering angle and delivers appropriate assist to the steering gear at all times, correcting for crowned road surfaces and cross-winds. This helps reduce driver fatigue.

In driver-selectable Sport mode, ELR’s steering gear provides increased on-center sharpness and steering sensitivity for dynamic steering. In the more relaxed Tour mode, it allows precise control with less driver steering efforts.

ELR’s continuous damping control monitors sensors throughout the vehicle, vehicle speed and the driver’s input, and adjusts damping accordingly for each 20-inch wheel every two milliseconds to maintain optimal vehicle ride control over varying road surfaces and profiles. This reduces and controls vehicle roll, pitch and vertical motions for a flat “sky-hook” ride performance, and instantly responds to cornering maneuvers by automatically adjusting the dampers to a firmer level for superior handling and stability. When driving on smooth roads, the dampers are automatically adjusted to the softest setting to provide increased isolation and ride comfort.

An isolated four-mount front cradle contributes to the ELR’s overall quietness, noise and vibration performance, and ride-and-handling dynamics. Specifically tuned mounts are tailored to the engine’s inherent torque axis, decreasing the transfer of vibration and noise into the cabin.

Now in its final months of pre-launch engineering testing, the ELR is slated to reach showrooms in the U.S. by early 2014. ELR is the first car by a full-line luxury brand to offer Extended Range Electric Vehicle technology. The EREV propulsion technology provides full driving range exceeding 300 miles (480 km), combining pure electric driving and an efficient, range-extending generator.