Promotion of electric vehicles

Electric cars and batteries can be separated? set the electric car
battery standard?including shape?size?voltage and power?etc.
On the country roads and highways can establish a service station
to replace batteries, because the unified standard of battery, when
the electric car battery power is low, can easily replace the battery
at any time. The station only need to prepare enough fully charged battery,
so that we can make electric cars more convenient.