Plug-in facilities are to be made available at intervals of less than 50 miles across motorways and primary A-roads, with the roll-out due to be largely complete by 2014.
It is the latest drive to bolster green technology by the Scottish Government.
However, the pace of extending the charging network drew criticism from the Scottish Green Party, which said it was too slow to meet climate change targets.
While electric vehicles are best suited to commuters making short city trips, anxiety about the limited range they offer – along with cost – is putting people off making the switch.
An electric vehicle driver could, in theory, get from Glasgow to the Scottish Border without running out of charge by using the existing network of 80 charging stations or the dozens located in supermarkets and motorway service stations.
However, they would face sizeable areas across rural Scotland where charging points are thinly spread, such as Ayrshire, the Highlands, Perthshire, Fife and the north-east.
While the Peugeot Ion and Citreon C-Zero can manage upwards of 80 miles on one charge if driven in cities, where braking helps regenerate the battery, the range drops when driven at motorway speeds, making even the journey between Glasgow and Edinburgh doubtful.
The latest funding of £2.6 million, including £750,000 from the Scottish Government, will allow charging stations to be installed at leisure centres, council car parks and workplaces.
Tourists will also be able to travel to Scotland's islands by plugging in at charging points due to be made available at ferry terminals, Government agency Transport Scotland said.
Transport Minister Keith Brown said: "The move to electric vehicles is good for our environment, helping to cut carbon emissions and reduce noise pollution, and will benefit drivers.
"We're already seeing exciting new opportunities for innovative Scottish businesses in the low carbon vehicles sector with firms such as Alexander Dennis in Falkirk, Allied Vehicles in Glasgow and Axeon Batteries in Dundee leading the way."
The Scottish Plugged in Places scheme, co-funded by the Department for Transport, has resulted in 300 electric vehicle charging points being installed north of the Border, 80 of which are available to the public.
A further 200 charging points are to be completed this year, while the programme to install charging points across trunk roads would be nearing completion by 2014, a Transport Scotland spokeswoman said.
However, the Green Party pointed out there were fewer than 200 electric cars licensed in Scotland by last summer and said more could be done to accelerate the uptake.
Patrick Harvie, the Scottish Greens' transport spokesman, said emissions could only be cut if more renewable electricity was made available through the National Grid and more effort was put into boosting public transport and cycling. He added: "The SNP is putting its trust in a single future technological marvel when it has options to reduce emissions now."
There were 198 cars, 66 motorbikes, 135 HGVs and vans licensed as electricity propelled last June, according to the DfT.