The Volkswagen Group may be putting a huge investment into plug-in hybrid vehicle technologies across a number of its brands, but it remains simply a “bridging” technology on the path towards longer-range pure electric vehicles, according to its global drivetrain chief.
Dr Heinz-Jakob Neusser, Volkswagen board member and head of Group powertrain development, recently told CarAdvice that the future for green vehicles remained EV, and that PHEVs and fuel-cell vehicles were essentially a patch.
“This [PHEV] is completely a bridging technology. We have two bridging technologies, on one hand is a plug-in hybrid technology and the other one is fuel cells, because both enlarge your operating range of the car when you have no recharging system available,” Neusser said.
“When you have a recharging system, the easiest way is to plug-in the car, recharge the battery and drive it electric.”
The Volkswagen Group currently offers a number of PHEVs (similar in conception to a Holden Volt) including the Golf GTE and Audi A3 e-tron, and has also produced a small number of XL1s. At last week’s Paris motor show it previewed two more, the petrol-electric Passat GTE and the Lamborghini Asterion concept. It has previously shown PHEV concepts such as the Cross Coupe.
But pure EV remains the ultimate end point for the Group, which aims to be a world leader in vehicle electrification before the end of the decade. Its MQB architecture that will underpin the majority of its small-medium cars and SUVs is geared up for just this eventuality.
This will be facilitated by VW internal battery development that will continue to bring significant improvements in the driving range of EVs, provided through greater energy density in the cells rather than the addition of larger and weightier battery packs.
“Batteries make the biggest steps in very short time frames,” said Neusser.
“In 2015/16 comes the next step, meaning we come from 25 to 28 Ampere-hours to 36-37Ah, then we are actually working on the next step, up to 60Ah. With research will come a completely new electro-chemical chemistry inside the batteries, and this will come at the beginning of the next decade.
“If you look to the e-Golf we have an operating range of 190km, and I expect that the next-generation in 2016/17 will increase to 300km and the following step will be around 500-600km.”
In other words, a battery of similar size could triple in capacity to around 80kWh, about the same as the larger and pricier (than an e-Golf) Tesla Model S flagship offering, which currently offers up to 500km of range. Speculation suggests a lithium-air unit could be the project.
However, just because a mainstream EV like an e-Golf, next-generation BMW i3 or the forthcoming more mainstream Tesla Model 3 are expected to offer greatly increased range in a short time frame, it doesn’t mean bridging technologies such as PHEV won’t be needed for a few years at least.
This is because greater battery density requires greater recharging capability, and the charging infrastructure in many world markets — Australia certainly included — dictates that PHEVs with their supplementary petrol/diesel power remain a necessity.
“It’s depending on the different markets, different countries and that all the infrastructure is there,” said Neusser.
“Because when you have such a high load and energy inside the batteries, you need a very powerful recharger — you can’t recharge with 3.6kW, it takes too long.
“You need at least 50, to 80 or perhaps 90kW recharging power and these are water-cooler recharging systems, very high-performance rechargers. But people are working on this and I expect that it will come, but will take a little bit of time until it’s there.”
The technology is, in fact, extant, with Tesla for example rolling out its 120kW Supercharger bases across the US, Asia and Europe.
“We are free with the plug-in technologies to bridge over that each country has time enough to bring their infrastructure this way,” Neusser said.
Meanwhile, the projected increase in vehicle electrification need not overburden the global power grid.
“That is not a big issue, if you look to the total power energy we have for example in Europe, only a very small fraction which is used for the automobiles, even when we have half of them equipped with electric,” said Neusser. “Most of the power goes to the heavy industry.
“We have now here in Europe nearly 20 per cent re-generational green power… this is not a big issue.”