Chevrolet Volt Plug-In Hybrid

There is growing pressure on General Motors to make “real” the concept car that the automaker introduced to great fanfare at the North American International Auto Show in Detroit this past January. That’s to be expected. The Chevrolet Volt represents what so many out there wish to see introduced at the showroom – a highly-efficient, electric drive vehicle that offers the hope of freedom from oil and high gas prices at the pump.

Now some of the enthusiasm is morphing into skepticism, with reports in several high-profile media outlets asking whether the Volt will be built at all. Some point to GM’s EV1 as an example of this automaker’s inability, or perhaps lack of commitment, to bring a real electric drive vehicle to America’s highways.  

Considering the engineering breakthroughs achieved in the EV1 program that are leading to a new generation of advanced GM hybrids, and hopefully to future electrically-driven hydrogen fuel cell vehicles, this seems a clear case of “no good deed goes unpunished.”

It’s true that the GM EV1 went away. But it’s equally true that we’re better for the experience than if this groundbreaking, but admittedly expensive and limited function, electric car never made it to the highway. It is leading to other, and presumably, better things.

A BETTER PATH?
These better things could include a vehicle based on the versatile Volt concept. The Volt is designed with GM’s E-Flex system, which would allow powering an electric drive vehicle with batteries, a hydrogen fuel cell, or a hybrid electric powerplant running on gasoline, diesel, or an alternative fuel like ethanol. In the Volt,  the most high-profile configuration is integrated – that of a plug-in hybrid vehicle allowing operation solely on electric power for up to 40 miles or so – something that conventional hybrids are incapable of doing today.

While E-Flex might seem a simple move to some, it really represents a fundamental shift in automotive engineering that could have a major impact on future vehicle models. E-Flex is no less exciting than the Chevy Sequel fuel cell concept, which utilizes a groundbreaking skateboard chassis design that houses all powertrain components, hydrogen storage, and more within a self-contained rolling chassis, with substantial use of by-wire technologies like drive-by-wire and steer-by-wire. Green Car editors are pretty excited about the Sequel’s approach, as are many in the industry. E-Flex presents an equally visionary approach.

In the same speech that GM chairman and CEO Rick Wagoner introduced the Chevrolet Volt concept, mention was made of the plug-in variant the company would develop for the Saturn Vue Green Line Hybrid. Even as the announcement was made and battery development agreements were referenced for the lithium-ion batteries GM said would power its plug-in hybrid, a cautionary statement was made. Wagoner shared that production timing for its plug-in hybrid “will depend on the rapid development of battery technology.”

This was an important bit of information that seems to have been missed by too many folks. It’s not that the automaker’s battery partners – a team comprised of Cobasys and A123Systems, and another a joint effort by Johnson Controls and SAFT – aren’t on the hunt for the required battery solution. There’s a lot at stake and plenty of work is being done at these companies and others. They fully expect improvements in battery cost and technology.

For those on the outside looking in, though, it’s just too easy to shape opinions based on speculation or, unfortunately, the conspiracy theorist view that taints the reality of what’s really taking place. Stepping back to gain perspective on where we’ve been serves well to illustrate where we’re heading, or perhaps where we’d like to be in the few short years ahead.

BATTERY EVOLUTION
The years since the 1990 Los Angeles Auto Show debut of GM’s Impact electric car concept, and the resulting EV1 production car that evolved from this show car, have shown that battery breakthroughs have their own timeline. This timeline doesn’t necessarily align with the desires of the market, no matter how intense the pressure or bright the hope. Predictions regarding exactly when that magic point of commercially-viable battery cost, energy density, and longevity will be reached have been spectacularly off the mark. There’s no reason to believe that predictions would be any more accurate today.

That said, batteries have come a long way. The nickel-metal-hydride (NiMH) technology pioneered by Cobasys, a company jointly owned by ECD Ovonics and Chevron, are at work in Cobasys batteries powering Saturn’s Vue Green Line Hybrid. They will also power the coming Saturn Aura Hybrid. Many other hybrids are powered by NiMH batteries from battery companies using technology licenses from ECD Ovonics.

The new generation of plug-in hybrids being pursued by several major automakers and a number of smaller companies requires more powerful battery packs than normal gasoline-electric hybrids. The reason? Plug-in hybrids are engineered to run entirely on battery power for up to 30-40 miles or more at a time. This requires enormous stores of energy similar to that needed to power battery electric vehicles. Some feel this can be done with NiMH batteries, while many others are pointing to lithium-ion (Li-ion) battery technology as the answer.

COST AN ISSUE
We’ve seen the evolution of advanced batteries in consumer electronics over many years. While power requirements for cellphones, laptop computers, and camcorders aren’t in the same league as electric-drive automobiles, the application of advanced battery technologies seems to be following a similar path. In the consumer products realm, nickel-cadmium (NiCad) rechargeable batteries made way for more powerful and certainly more environmentally compatible NiMH batteries. Today, those looking for greater power to provide longer single-charge operating times often turn to laptops using lithium-ion batteries, although these come at higher cost.

The cost differential between technologies is a reality in the automotive world as well. Just as NiMH batteries are substantially more costly than the advanced lead-acid batteries that powered the first-generation GM EV1 electric vehicle, Li-ion batteries are even more expensive…exceptionally so, in fact. That doesn’t mean this battery technology should be dismissed as impossibly expensive or that it shouldn’t be explored. This didn’t keep Nissan from choosing lithium-ion batteries to power the limited-production Altra EV minivan it test marketed in the 1990s, and it hasn’t kept upstart companies like Tesla from integrating Li-ion batteries in its electric sports car. Rather, resources should be focused on Li-ion and any other potentially viable battery technology that could resolve the battery issue and make plug-in hybrids, and ultimately battery electric vehicles, truly viable and cost-efficient. The reward is worth the risk.

It’s interesting that cost is too often ignored as a factor in the discussion of electric and plug-in hybrid vehicles. Plug-in hybrid interests – a conglomeration of would-be plug-in hybrid owners, electric utilities, battery electric vehicle enthusiasts, and battery companies – rarely address this in their efforts to promote the point of view that plug-ins are the “ultimate” and immediate answer to an industry so dependent on oil to operate its products. However, according to presentations made at a recent plug-in hybrid technology workshop attended by Green Car, current plug-in hybrids – typically Toyota Prius hybrids modified by other companies to operate as plug-in models – cost upwards of $10,000 or more than the standard hybrid model upon which they are based. That’s an unacceptably high differential cost in the consumer world.

While the goal of commercializing plug-in hybrids is admirable and should be pursued without hesitation, it’s disingenuous for proponents to simply skip this important point altogether. It’s also a disservice to a public that’s too often led to believe plug-in hybrids represent a quick fix to America’s dependence on imported oil, or the latest, that they also provide the sole long-term answer and make hydrogen fuel cell vehicle efforts obsolete. Those who buy into this without considering the facts are simply being misled.

This is why telling the whole story – as GM is striving to do – is so important. The reality is that plug-ins can only become a commercial reality when the batteries that enable their operation are much more reasonably priced than they are today. Important issues like ensuring consistent operating temperatures and long-term battery durability in an environment of constant charges and deep discharges must also be sorted out. There’s a lot of work still to be done.

If General Motors is guilty of anything, it’s of being forthcoming enough to admit that even as the company is pursuing a vehicle platform and powerplant it believes is crucial to the automobile’s future, battery challenges remain that could directly influence the timeline of a commercial introduction at new car showrooms. This view is mirrored by DaimlerChrysler, which has also said that a dramatic leap in battery technology is necessary to make its Dodge Sprinter plug-in hybrid viable in the marketplace.

The reason for this caveat? Unreal expectations are being fueled by plug-in interests because these battery challenges are rarely part of the pitch. Yet, battery cost and durability challenges remain. This is a sobering truth that’s better understood than not. Let’s just not shoot the messenger.

 

Photo by David Middlecamp