Electrifying GM

March 1, 2020

Lindsay Brooke

General Motors’ long, convoluted journey toward vehicle electrification has finally arrived at an earlier-than-expected destination: total commitment to a battery-electric future. GM is officially “all in” on BEVs as its future propulsion strategy, with some 20 electric models slated for launch by 2023. The Detroit-Hamtramck plant is being transformed into GM’s first dedicated EV production facility. Its product cadence, set to begin within the year, will be led by electric Chevrolet and Cadillac crossovers. Joining them is GM’s first electric pickup that will resurrect the still-popular Hummer nameplate within the GMC brand.

The company aims to sell one million EVs globally by 2026, asserts CEO Mary Barra, while it continues to evolve its profit-driving IC-powered trucks and crossovers (and develop self-driving vehicles with tech partner Cruise). It’s an ambitious plan that ends GM’s 20 years of hybrid-vehicle development. That extensive HEV roster included belt-alternator “electric assist” systems; “Two-Mode” transmissions co-developed with Daimler and BMW; 42-volt starter-generator pickup trucks and two generations of Volt range-extender hybrids that included Volt’s Cadillac spinoff, the obscure ELR.

“I want to go right to battery-electric vehicles; I’m not going to spend money on hybrids,” asserted GM President Mark Reuss, during a January media roundtable at the Detroit plant. Reuss was responding to a reporter’s question about why GM doesn’t simply break from the U.S. federal clean-air regulations and instead follow California’s standards, thus helping to lead the industry toward a single standard.

Reuss argued that the California regs, on both a business and greenhouse-gas basis, favor hybrids. Leadership in zero-emission vehicles is “what we’re trying to do” for a long-term solution, he said.

The billions spent on HEV programs, and the Bolt EV program that followed, brought GM vital learnings in systems engineering, battery chemistry, power control, thermal management, charging, customer usage and even brand power. All underpin work on the next generation of EVs, said Tim Grewe, GM director of battery cell engineering.

Clayton Christensen, the Harvard Business School professor who studies impactful technologies, might describe GM’s electrification path until now as “sustaining innovations” — those making a product or service “perform better in ways that customers in the mainstream already value.” By contrast, “disruptive innovations create entirely new markets through the introduction of a new product or service.” GM’s unfairly maligned EV-1 certainly was innovative in 1996, for example, but lacked a cutting-edge battery for real market disruption. It also lacked a market. Three decades later, a global market and infrastructure for EVs are growing and GM’s resources and leadership focus are vastly different.

“There will be no losses here [Detroit-Hamtramck]. Every car that comes out of here will be profitable,” Reuss told SAE’s Automotive Engineering during the media discussion. “Obviously, how much profitability we dial in will be scale-driven,” he said. “But the global manufacturing footprint and new [battery] chemistries will allow us to be profitable.”

New product approach

While the “D-Ham” plant announcement in January was North America-centric, Reuss asserted that GM’s EV blitz involves the company’s worldwide operation. “These are global vehicles,” he said. “The battery strategy and architecture in particular are very global. When we design our new battery packs, we have the ability to go from battery systems that, from a cell level, can be configured as a low-roof/low-floor [vehicle] entry—and you can imagine the cars that can come off of that—to a mid-SUV basis, to a full truck platform.”

The new battery systems are designed to accommodate varied cell form factors—prismatic cell structures used in China, or what Reuss calls GM’s “more mainline” pouch-type cells developed by battery partner LG Chem for North American use. He said the flexibility to do different cell and pack configurations enables a manufacturing footprint that differs significantly from current practice.

“As we begin, the big cost of an EV will be the battery electronic system,” to be progressively reduced by scale. GM’s new strategy is to vertically integrate the majority of its global battery, electric drive and power control engineering and production operation. “You’ll see [GM] footprints in lots of different places” including a new GM-LG Chem Lordstown, Ohio, battery factory.

The decision to bring all aspects of electric-propulsion component and systems development in-house marks a significant change in strategy from that used during the Bolt EV development in 2015. For that program, GM partnered with a newly dedicated group within LG Corp. in Korea to develop 11 new and unique components and subsystems for the car, including the battery cells and pack; traction motor (a GM design); power inverter; high-power distribution module and other related hardware. At the time, Reuss claimed Bolt would “set new standards for EVs and electrified-vehicle development,” calling the GM-LG partnership a “disruptive move.”

New vehicle architectures (see chart, p.21) with common geometries and increasingly shared bills-of-material are aimed at global scale, Reuss said. Any decision to put an electric pickup truck in China (not as far-fetched as it sounds) would be driven by market demand, for example. Describing GM’s new EV architecture, known internally as BEV3, Reuss compares the significantly more compact battery-pack configuration to an “ice-cube tray” rather than the nowubiquitous “skateboard” term that was first coined by GM engineering executives Larry Burns, Chris Borroni-Bird and Bob Purcell to describe the structures used in early 2000s concept vehicles.

Reuss indicated that GM has more optimal solutions to package its new battery packs to scale across the global product portfolio. “We created the [skateboard] term,” he acknowledged. “But do you think we should be doing battery-electric trucks or Cadillacs off a skateboard?”

He indicated that GM will go to market with batteries in a different way. “Everybody wants to talk about dollars per kWh — which is important, but so is the way you configure the battery, size it and use it,” he said. “It’s equally important on the cost-parity curve. It’s a big opportunity for us.” GM is “investigating new approaches to battery package-efficiency and thermal management for the new generation of EVs,” a supplier engineer with insights into GM’s battery development tells AE.

For its electric drivelines, GM has developed “different output motors for all of them [vehicle architectures], Reuss reports. “We can do anything we want depending on the entry and do it in a scale and torque capacity that is very high, as well as something that is very low.” Precise axle control — a key feature of electric drive systems — is a focus for all driveline types (FWD, AWD, 4WD). For the Hummer EV pickup, which GM’s Super Bowl TV ads claimed will deliver 1,000 hp (745 kW) and tugboat-like 11,500 lb-ft (15592 Nm), each wheel is said to offer separate motor control.

Optimizing manufacturing

The full-house transformation of Detroit-Hamtramck “represents GM’s chance to redefine how they build vehicles,” observes Brett Smith, director of the Propulsion Technologies & Energy Infrastructure Group at Ann Arbor, Michigan’s Center for Automotive Research (CAR). “It doesn’t mean they have to change everything, but it gives them the ability to look at processes now and ask why, or why it doesn’t, make sense.” Smith compares the scope of changing to an all-EV production scenario to Ford’s steel-to-aluminum transformation of the F-Series pickup and full-size SUV ranges.

Smith noted that moving to EVs offers opportunity “to redefine what a module is and what is shipped into the assembly plant and how it’s assembled.” Some of that will be based on labor contracts and some based on process improvements, he explained. And for suppliers, “there is opportunity to add more value to a shipped product.”

At the media roundtable, Reuss announced that GM’s currently pushing for increased platform, component and system consolidations. Known as “reductive design,” the effort has already reduced inbound part numbers across plants by more than 3,000 individual pieces, on average.

“They’re adding the technology while eliminating the unneeded in-plant and vehicle complexity. It’s the only way they can make the investment in both the IC and EV programs,” noted manufacturing expert Laurie Harbour, CEO of Harbour Solutions.

She says that while the industry’s move to EV-exclusive manufacturing facilities is “a huge change,” the majority of vehicle assembly will be familiar—body shop process, installing closures, instrument panels, etc. “Transitioning to EV production is really more about the body ‘marriage’ area,” where the body/chassis and electric propulsion and energy-storage systems come together. She and CAR’s Smith agree that Tier 1s chosen for EV programs are those that have invested in their own R&D for electric mobility, including modular assembly.

The veteran analysts are bullish on GM’s electrified transformation. “GM’s made big investments in both process and product for this,” Harbour said. “I’m sure they’ll use the learnings from [Detroit-Hamtramck] going forward. Excluding the labor-contract element, I think it’s the reason they put this plant in Michigan, located near their headquarters and main engineering center. Engineers, purchasing people and everybody who needs to learn from both the positive lessons and the mistakes can capture it all right there.”

Industry eyes are on GM’s all-in foray into dedicated EV development and production, as they are on Ford Cuautitlán, Mexico [Mustang Mach-e assembly], Rivian’s ramp-up in Normal, Illinois and other GM competitors on similar paths.

Says Harbour: “I see this as a pinnacle for GM. I’m excited for them. They know how to manufacture. They know how to make money— they did it despite a 40-day strike [in 2019]. They’re doing a lot of cool stuff in the electrification area.”

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