Preserving the internal combustion engine: one professor's prescription

As automakers transition to battery power, how long is the road ahead for the internal combustion engine?

New supplier alliances are ensuring a stream of vital batteries, software and electronics for anticipated demand for electric vehicles. Battery ranges of 300, 400 and even 750 miles are being claimed. What was a slow crawl toward an electrified horizon a year ago has become a jog as automakers announce EV models, provide higher EV-portfolio percentages and predict 100,000-vehicle sales.

Anna Stefanopoulou is a professor of mechanical and electrical engineering and William Clay Ford Professor of Technology at the University of Michigan. Her research interests are the modeling and control of internal combustion engines and electrochemical technologies such as fuel cells and batteries.

With one intellectual boot in each powertrain camp, she is well positioned to provide perspective on the future of internal combustion. She spoke with Shift correspondent Jack Keebler. Here are edited excerpts.

Q: What is driving the acceleration in automakers' efforts to transition from internal combustion-engine vehicles to battery-powered vehicles?

A: It's tightening global emission re- quirements. To manage the climate crisis, we need to decarbonize transportation. And it's more than what cost-effective IC engines can afford us. It's the realization that we need to accelerate decarbonization. With the fossil fuel we're using now, it's hard to manage the CO2 we are emitting. That pollution reduction requires more and more expensive aftertreatment. For greenhouse gases, it is very hard to achieve the trajectory we need with cost-effective IC engines alone.

Q: Do you see a time when automakers stop producing ICE-powered vehicles, or will it simply taper off?

A: I think it will be a tapering off. But it will take a really long time to develop the [EV] infrastructure and turn over the fleet. And it will require a dramatic type of policy. We are going with a decarbonization trajectory from various climate-change bodies, like the IPCC (Intergovernmental Panel on Climate Change). That trajectory projects half a billion electric vehicles on the road — in use — by 2035 or 2040.

Q: Are there affordable ways to extend the life of ICE-powered vehicles to improve their fuel efficiency and reduce CO2?

A: Absolutely! Technologically, the issue is cost-effectiveness. Hybrids and plug-in hybrids have an IC engine and are electrified. Frankly, they were progress. But we'll require further improvements.

So far, what we have been doing is slapping together existing IC engines with batteries. But we can dramatically improve the IC engine when we have the power management of a [powerful], reasonable-size battery. These hybrids could work better for specific cases, where the grid's electrons do not come from renewables, where there is a cold climate or for high speeds and long distances. And there is a big difference between serving urban and rural environments.

Going forward, all the highly efficient IC engine technologies have transient-dynamic management issues. Therefore, they would all greatly benefit by optimizing their combustion-mode switching with hybridization. But of course, we must make these new hybrid powertrains cost-effective, robust and profitable. An all-electric vehicle is in principle, and ultimately could be, much simpler and more cost-effective.

Q: What big challenges remain for batteries to realize their full environmental and efficiency potentials?

A: There is a lot of work to be done. How do we manage the end of life? How do we improve repairability, remanufacturing, repurposing these very large batteries? Batteries are modular. How do we create and tailor electric vehicles to the needs of customers? You don't want to just drive around with a big bench full of cells. Design for disassembly is major. We want to manage to do this safely, in semiautomated, small local shops. We have the skilled technicians and sophisticated tools to repair current vehicles. That's not the case with battery-electric vehicles now.

Q: Is the cost-benefit ratio changing for internal combustion engines and batteries? Engines that will comply are quickly becoming too expensive, and battery power is potentially becoming more affordable.

A: Again, we must stay on the fastest trajectory for decarbonization. But the cost-effectiveness of the IC side is saturating or plateauing. And you are seeing continuous, accelerated cost improvement on the battery side. We need to be focused on that. What is the fastest, best pathway to decarbonization? In the end, when we understand that point, it's not about one technology versus the other. They will have to coexist for quite a while. But our students, when they go to work for big international OEMs, even for those in Japan with significant hybrid-IC-engine investment, have come back to ask me if they can take battery courses to understand, prepare and contribute to a fast and smooth transition.