VW Group head of research says it’s time for electrification, but progress has been extremely low; “We need more”
In the keynote address at the 4th Symposium on Energy Storage: Beyond Lithium-ion, hosted by the Pacific Northwest National Laboratory (PNNL) in Richland, Washington, Jürgen Leohold, head of Volkswagen Group research (and 2009 EUCAR chairman), said that one of his key messages was that although the automotive industry is really at a turn in time toward electric mobility, the progress compared to other technologies made in the 111 years since Ferdinand Porsche introduced an electric vehicle at the world exposition in Paris has been extremely low.
That car, Leohold noted, had a lead-acid battery pack with about 24 kWh of energy, was propelled by wheel hub motors and had a range of about 50 km—“not that much different than today. We definitely need more for electromobility to become established in the market.”
In the 1970s Volkswagen had put two electric cars on the market, but sales figures were in the two-digit numbers, Leohold said.
So what has changed? What has changed the business mainly is that Li-ion batteries have come around and finally supported an energy density that allows you to build a halfway decent car.—Jürgen Leohold
Leohold cited a number of drivers for the current movement to electromobility (that were largely echoed by other speakers during this first day of the symposium):
- Climate change and emissions;
- Urbanization and megacities; and
- Shortage of fossil fuels.
For an industry like ours, where products are dependent for more than 90% on oil derivatives, this is a very critical situation. We are very much convinced that we must initiate a change. Any change in the drivetrains will take a long time, so we have to start now to address these issues.—Jürgen Leohold
To limit warming to 2 °C, the annual emissions reduction has to move from a 20% target in 2020 to a 2050 target of up to a 95% reduction in developed countries. It will not be enough to improve the efficiency of conventional engines or to launch alternative fuel concepts, Leohold said. To fill the gap to sustainable and zero emission mobility, clean drive technologies, such as the electrification of the drivetrain, will be required. However, he stressed that “new forms of mobility cannot be separated from the question of where the energy is coming from”—a reference to the need to widely deploy low-carbon sources of electricity.
Electricity used to charge plug-in vehicles should come exclusively from renewable energy resources, such as wind and solar power, he suggested—otherwise, there is no greenhouse gas emission advantage over a conventional vehicle with optimized fuel consumption.
Volkswagen is taking a three-step approach to address these challenges, he said.
- Increasing the efficiency of existing drivetrains, usually the fastest approach and a very effective approach.
- Convert to new types of fuels that are fairly CO2 neutral such as biofuels, although Volkswagen thinks the potential of biofuels worldwide is limited to 10–20%. “But nevertheless, that’s something.”
- New technologies, and electromobility part of this.
Based on well-to-wheel projections factoring in improved conventional technology and electricity sources over the next 9 years, Leohold noted that:
The electric vehicle is not really that big an improvement compared to conventional engines if you consider technical progress. The only way to get real drastic improvements in terms of energy use and greenhouse gas emissions is if you change the energy supply. Meaning that either with fossil fuels you go to biofuels, but that potential is limited as I mentioned already, or we go to renewable resources...with the electric drivetrain.
...This is not enough. If you look at 2050 and 2 degrees, this cannot be reached by any fossil fuel approach or conventional drivetrains. It requires electrification of the drivetrain. Since the ideal battery is not around yet, we have to introduce hybrids.—Jürgen Leohold
The range issue. The biggest challenge for electric vehicles, reaching back to 1900, is the limited range. Today, actual range could be as low as 80 km out of a theoretical 150 km given cold temperatures or other adverse conditions or behavior, he noted. By contrast, the Golf diesel BlueMotion has a 1,447 km range.
The big question is how will the customer react to this change in performance? Will they accept cars with this limitation? We think many will change, especially those with second cars.—Jürgen Leohold
While vehicle-level approaches such as lightweighting can squeeze out some additional range—dropping 100kg could increase the range by 3.5% on an EV, Leohold said—modifications such as that are “not really significant. The main challenge is the battery.”
Requirements for future electrical energy storage system. Leohold said that Volkswagen was confident that by the end of the decade, there be commercially available Li-ion batteries with an energy capacity in the range of 200 Wh/kg, perhaps a little bit more, up from the approximate 120 Wh/kg of today.
However, the industry needs a technology change to deliver the next stage of batteries, with capacity on the order for 400-600 Wh/kg. And “to build a decent type car”, the industry needs capacity on the order of 1,000 Wh/kg.
There may a 150-mile range in a regular [electric] car by the end of the decade, but we doubt we will reach more as long as we are limited to Li-ion...A mass market [for EVs] depends on the range of these cars. This is where we put much hope on future technologies.—Jürgen Leohold