In an article on Motoring.com.au, Volkswagen Auto Group's head of powertrain development Dr Heinz-Jakob Neusser recently said that plug-in hybrid technology is merely a stop-gap until battery technology is able to increase range significantly.
Full article here titled "Volkswagen expect 500km battery range by 2020":
"At one end there is plug-in hybrid technology and at the other is fuel cells, because both enlarge your operating range of the car when you have no recharging system available. When you have a recharging system it's the easiest way to plug in the car, to recharge the battery and to drive electric."
"We have to look to the e-Golf, which had an operating range of around 190km," said Dr Nuessen. "I expect the next generation in 2015-17 will increase to around 300km and the following step will be around 500-600km."
Full article here titled "Volkswagen expect 500km battery range by 2020":
http://www.motoring.com.au/news/2014/volkswagen/volkswagen-expects-500km-battery-range-by-2020-46561