Massive electric car batteries provide great range – and lots of dead weight

  • The GMC Hummer EV Edition 1 pickup truck tips the scales at over 9,000 pounds, with a battery pack that alone weighs more than some entire cars.
  • Automakers recognize the need to increase efficiency across the board going forward, but current battery technology does not yet have an energy density that makes it possible to maintain the range and performance demanded by consumers with smaller battery packs.
  • The Lucid Air Grand Touring achieves a whopping 516 miles of range in a much smaller package than the Hummers, but it still weighs over 5,200 pounds — and costs more than $140,000.

    There’s no getting around it: the new GMC Hummer EV, which turned heads at The Amelia Concours in Florida on March 6, is a heavyweight. According to test data, the Edition 1 tips the scales at 9063 pounds, with about a third of that (2923 pounds) in the battery pack alone. The package weighs more than a Honda Civic sedan.

    To give the beefy 1,000-horsepower premium Hummer more than 350 miles of range and eye-popping acceleration required a whopping 210 kilowatt-hour (kWh) battery pack. It’s a far cry from the late Lotus founder Colin Chapman’s memorable phrase, “Simplify, then add lightness.”

    GM declined to comment, but Carlos Tavares, CEO of Stellantis, said in a phone interview that it’s a “valid” point that cars should be lighter. “It’s harder to drive heavy cars,” he said. “The second issue has to do with scarce raw materials [that are slowing down auto production]- More of these materials are required to make larger cars. So, yes, we need to make cars lighter, so they will use less energy. Lighter electric cars will not need to carry such large batteries and will have shorter charging times.”

    Just because the obvious solution is to get to smaller packages by reducing vehicle weight with downsized components and lightweight materials like carbon fiber or aluminum, don’t expect the industry to necessarily move decisively in that direction. Price is a consideration. Americans like their big cars (Hummers included), and some industry insiders argue that the critical sustainability issues will actually move elsewhere.

    The Hummer EV, which weighs more than 9,000 pounds, was a hit at The Amelia Concours in Florida.

    Jim Motavalli

    Anthony Schiavo, director of research at Lux Research, is the author of the Electric Vehicle Lightweighting 2030 report, which predicts that battery pack densities will increase by 15 percent over the next decade. “Battery performance, energy density and cost have improved very dramatically, reducing the cost penalty for larger battery packs,” Schiavo said in an interview. “We’re around $100 to $120 per kilowatt-hour now. An important takeaway for automakers is that the way to increase range is to use bigger packages, not a ton of very expensive carbon fiber and advanced composites — the hallmark of early cars like the BMW i3.”

    Schiavo says that we should not judge electric cars by old environmental standards. “Obviously, a 9,000-pound Hummer is not sustainable, and it’s not the type of vehicle you’re going to use to get the groceries,” he said. “But these are electric cars, without the emissions problems inherent in combustion. I think key considerations for future designs will be lighter weights for cost reduction – using cheaper and thinner materials – and material supply. The material came via unsustainable mining or from conflict areas?”

    “Yes, we need to make cars lighter, so they will use less energy.”
    —Carlos Tavares

    Although it’s dying now, Schiavo believes the kind of electric car battery swaps proposed by the now-defunct Better Place could make a comeback. “It’s coming into its own in China for fleets through companies like Nio,” he said. “We expect to see more switches, especially if an EV brand becomes dominant in sales and there is some battery standardization in the industry.”

    Still, automakers can and will try to reduce the weight of their electric vehicles. John Catterall, vice president of the automotive market for the American Iron and Steel Institute, acknowledged that improvements in battery technology could reduce the need for lightweights. But in an interview, he said that high-strength steel for products such as battery holders “will mean that automakers can get away with thinner materials that can take a higher load. We need to work to get the mass down on electric cars, and reductions of 25 percent are possible in cars that use high-strength steel.”

    gmc hummer ev is a first super truck of its kind developed to create new roads without emissions

    The GMC Hummer EV Pickup offers a 329-mile EPA combined range.

    GMC

    powered by next-generation ev propulsion technology, the gmc hummer ev will be the first all-electric addition to gmc's lineup and will bring gm another step closer to an all-electric future

    The battery in the Hummer EV Edition 1 alone weighs more than an entire Honda Civic.

    GMC

    These battery holders can also be made of thermoplastic resin, says Matt Zessin, automotive marketing director at M. Holland Company, which distributes such products. “Electric cars are relatively new to our market,” he said in an interview. “But batteries are a major component of the vehicle’s weight. We’re looking at the whole landscape, including the trays and covers.” The specific solution is fiberglass mixed with polypropylene, which is already used in instrument panels and center consoles, he said.

    Carbon fiber, seen in many electric cars, has huge weight advantages, but Zessin said “the problem has been getting carbon fiber to a price point that makes sense for the market.” Carbon fiber really makes sense on high-end electric supercars, and for some parts. Carbon Revolution, for example, is an Australian wheel manufacturer that has supplied Ford (including for Shelbys), Ferrari and General Motors (Corvette Z06). The company says it has six programs in production with three global companies, and another nine programs in development. On electric SUVs and pickups, it said, “very meaningful range-extending benefits” are possible.

    In the April issue, Consumer Reports surveyed the range of current electric cars, with the Lucid Air Grand Touring at the top, 516 miles on a charge. The closest competitor was the long-distance version of the Tesla Model S, with 405. The Grand Touring’s battery pack is 112 kWh, large but not the largest on the market. Tesla’s pack is only slightly smaller, at 100 kWh. The Hummer EV’s 210 kWh provides 329 miles – a result partly explained by the vehicle’s weight. So what’s Lucid’s secret?

    2022 clear air

    Increasing efficiency is a priority at Lucid, with weight reduction a major focus.

    Lucid Motors

    Eric Bach, senior vice president of product and chief engineer at Lucid Motors, told Autoweek that getting more miles out of a battery pack with a certain amount of stored energy has a number of dimensions. “Our drag coefficient of 0.20 is world class, and we have a small frontal area on the air,” he said. “We have low rolling resistance in our own tires, in all layers and in the whole system. And we lightened the powertrain, which includes engine, differential, gearbox and inverter. It weighs only 74 kilograms [163 pounds]. Tesla’s unit in the Model 3 weighs 92 kilograms [202 pounds], 30 percent heavier and less powerful. And so it’s our overall effort to make the whole car as light as possible.”

    The Grand Touring is no lightweight—it tips the scales at 5,266 pounds. Most electric cars are heavy and won’t please Colin Chapman anytime soon. Batteries are still a big burden to carry, but automakers are using every means at their disposal to build efficient cars around them.

    Share your thoughts on everything EVs, battery packs and the relative strength of both in the comments below.

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