Practical low emissions electric cars have been hampered by severe distance restrictions and the length of time it takes to re-charge batteries while petrol electric hybrids have been great at cutting emissions but nothing special on fuel economy.
But now hybrid pioneers Toyota may have come up with a compromise hybrid battery car that takes the best of both options. Called the Prius Plug-In it is the latest in the Prius family that has sold 2.6 million world wide and 67,000 in the UK since 2000.
The major breakthrough is the development, in conjunction with Panasonic EV Energy, of a compact, lightweight 56 cell 4.4kWh lithium-ion battery pack that is almost four times more powerful than the battery used in a standard Prius.
It is less than half the size of previous lithium-ion battery packs at 87.2 litres and exactly half the weight at 80kg - which is only 35kg heavier than the nickel metal-hydride battery used in Prius – but, most importantly, takes just 90 minutes to recharge from a standard 230V domestic power supply.
This is used to power a 60 kWh permanent magnet electric motor which works in tandem with a 98bhp four cylinder 1.8-litre petrol engine which gives a total output from the Hybrid Synergy Drive system of 134bhp and results in a zero to 62mph time of 10.7 seconds and a 112mpg top speed.