The biggest barriers to electric car adoption are range anxiety and recharge times. We may not do long journeys very often (the average journey is under 10 miles) but every now and then we want to go visit relatives, or have a day out, or go on holiday, and those journeys are considerably longer.
This lack of flexibility in electric cars is holding up mass adoption. Even when batteries get to the point of being able to cover 300+ miles per charge, in all weather conditions, recharge times are still so long as to make touring impractical.
How to get around this? Manufacturer car rental schemes.
What I mean is that the manufacturer who produces an electric car starts offering a swap-out scheme. So you can drive your electric vehicle daily, on all the short journeys (to work, to drop off the kids, to go shopping), but you can then simple swap it at your local dealer for a petrol car if you have to do a long journey.
To be fair, this scheme wouldn't just benefit electric cars but could help us all drive smaller cars. Most journeys don't require a car capable of carrying four or more people and a boatload of luggage. Yet we buy vehicles for those scenarios.
I could certainly do my daily commute in something the size of a Smart car. But for travelling long distance or taking rubbish to the tip I need more space. Being able to quickly and easily swap my car for something more appropriate, I wouldn't need a one-size-fits-all vehicle.
In terms of electric cars, you remove the barriers regarding range and open the market up to people who need infrequent flexibility.
Obviously it would need to be very flexible, available at short notice, probably something using an app without any need to interact with a booking service. I don't see any technical factors that couldn't be overcome though.
It would provide the peace of mind needed to clear those final hurdles.