EVolution: 11 keys to GM’s electrified futureEVolution: 11 keys to GM’s electrified future

From 2020 through 2025, GM plans to invest more than $20 billion—more than $3 billion annually, on average—toward electric-vehicle programs. And by the middle of the decade, the company aims to sell a combined one million EVs annually in its two largest markets of the U.S. and China. 
“We want to put everyone in an EV, and we have what it takes to do it,” CEO Mary Barra said in an opening address Wednesday at EV Day, which showed media and investors the company’s dedication in setting its “all-electric future.”
GM president Mark Reuss said GM’s focus on EV development is now at about 60% up from 20% before the pivot to emphasize all-electric vehicles. 
“This is a huge opportunity for us—perhaps the biggest opportunity the company has ever seen,” Reuss said. “Everything we see today is real,” he said, and representative of those efforts. With that, the company showed a dozen vehicles and vehicle concepts at various stages of development, as well as a detailed look into what will differentiate its Ultium propulsion technology—especially the battery part of it.
Doug Parks, GM’s executive VP for product development, purchasing, and the supply chain clarified to Green Car Reports that the Ultium name refers to anything that moves the vehicle. GM claims to have more than 3,000 global patents for electrification, mostly focused around propulsion. 
GM Ultium propulsion system for EVs
Here are some of the many ways that GM is planning to apply the expertise of the past plus an ambitious economies-of-scale approach to its new generation of electric vehicles. 
Cost is a moving target. Ultimately, GM is working toward a cell cost of less than $100 per kwh, and officials said that it sees $120/kwh, on a pack basis, within reach. Earlier efforts in which an OEM fully owned the cell-production side—like Nissan with AESC, for instance—didn’t work out so well, but with the LG Chem joint venture GM is hoping that the aggressive investment in the battery portion of the business will pay off, with potential licensing of the tech to other companies like ride-share providers.
One floor or two. The modules are all on the same level (as opposed to putting a select few “upstairs”), which helps simplify cooling for the base pack design and relates to safety. Two-level packs will have additional cooling measures. In either case, the pack will have the capability to isolate cells or entire modules when needed.
GM EV day – battery
Chemistry gets an ‘A’. The battery chemistry itself is called NMCA—cutting cobalt, increasing nickel, and adding aluminum (the ‘A’) to the cathode. They’re based on the latest LG Chem product line but co-developed by GM in Michigan. “The crown jewel of the Ultium system is the battery cell itself,” said Adam Kwiatkowski, GM’s director of advanced vehicle design. 
Big, big cells. The focus, according to Andy Oury, lead engineer for the battery packs, was to “let the cell be all it can be.” To that, pouch cells provide a packaging and design advantage, and they’ll soon provide a cost advantage. GM chose to apply large-format cells, with the widest electrode rolls in the industry—”the fewest number of the largest cells possible,” as he put it—to help cut wiring and connectors within the modules. The 100-Ah cells GM is using are each the equivalent of about 20 of the 2170-format cylindrical cells Tesla uses in its Model 3 and Model Y, Oury said.
Forward thinking. The battery management system is in the module. This not only allows for the possibility of future cell upgrades without fully designing the pack or other propulsion-system components, it’s also “a big enabler for service in the future,” allowing for the possibility of new or improved modules being replaced or upgraded.
600 miles is possible mid-decade. GM is working on the development of a lithium-metal cell that will provide about double the energy density while fitting, with an adapter, into the modules with the same form factor as the large-format pouches. GM won’t be using them before 2025, but they could be used in products shortly after that. Those future products will still be using the same pack design and propulsion components as the current generation.
Think of the biggest trucks as having two packs. The battery modules include cells that are stacked horizontally for low-roof vehicles or vertically for trucks and SUVs. The latter allows for 800-volt charging with a trick—treating each of the two full 12-module layers as separate packs and wiring them in series.  
Million-mile batteries in sight. These batteries are designed to last hundreds of thousands of miles, and heavy duty cycles in shared mobility was part of the criteria when choosing cells. A million-mile battery life is “within striking distance,” according to Oury.
GM Autonomy concept, 2002 Detroit Auto Show
No skateboarding! GM president Mark Reuss previously made clear to Green Car Reports that GM’s BEV3 architecture is not a skateboard—despite the fact that GM is the originator of the whole skateboard strategy. The company worked to clarify what the differences are at its presentation and why skateboard strategies are actually limiting: Neither the entire BEV3 component set nor its Ultium electric propulsion technology are limited to a particular chassis or body floorpan. This means that cars and crossovers can continue being uni-body while the toughest electric trucks can be body-on-frame, and still share components. Many of the cars and crossovers will be built with some shared body and chassis components nevertheless. 
One motor family. There are three motors that are part of the architecture, including two permanent-magnet motors and one induction motor. All three of the motors were internally designed by GM, but they’ll be built by multiple outside suppliers. Vehicles built on the Ultium building blocks will have a total output varying from 235 horsepower up to 1,000 horsepower, achieved with combinations of one, two, or three motors, from three potential motor designs: a 70-kw induction motor, a 180-kw permanent-magnet (PM) motor, and a 255-kw PM motor. There will be multiple power ratings for each motor configuration depending on the battery configuration. 
Motor for GM Ultium propulsion system
Front-drive for efficiency, double the rear-wheel drive for performance/off-road. GM says that its modular platform and drive-unit strategy is the first such plan in the industry to support front-, rear-, or all-wheel drive. One more interesting point at this time when EV platforms all seem to be preferring rear-wheel drive: Efficiency-focused models might still have all-wheel drive by using the PM motor in front with the induction motor in back—the same strategy as Tesla has employed in the Model 3, but at opposite axles. At the other end of the spectrum, the Hummer SUT, Hummer SUV, and others might use three of the 255-kw motors (two in back, one in front) for a total of 1,000 horsepower.

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