Plugging in an electric car should be as easy as making a call on a cell phone—only it isn't always.

Now a series of new agreements—similar to cell-phone roaming agreements that let users make calls on other networks—are beginning to make that easier.

The latest, announced Tuesday morning, is an agreement between ChargePoint, America's largest charging network, and FLO, the largest network in Canada.

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The agreement will allow electric-car drivers with ChargePoint accounts to see FLO chargers in their ChargePoint apps when they're traveling in Canada and to plug in to any one of them using their ChargePoint account—and vice versa.

ChargePoint signed a similar agreement last Tuesday with EV Box, one of the leading providers of charging stations in Europe. The EV Box agreement will allow travelers renting an electric car on either continent to use their ChargePoint or EV Box account from the other. EV Box operates in 45 countries.

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Such interoperability agreements depend on a common set of new charging standards used by networks, automakers, and charging station producers called Open Charge Point Interface.

It bundles billing, account, charger location and availability information, among other things into a common protocol communicated between the car, the charging station, the network, and its app to allow drivers simply to plug in and go.

Before drivers show up at a charger on any of the apps, they can see whether the charger is available, working, or in use, and the price to charge. 

Behind the scenes

The announcements come on the heels of an announcement by Hubject, another company working behind the scenes to integrate the data streams of different chargers and charging networks and their apps into one common standard to enable agreements like those between ChargePoint, FLO, and EV Box.

Hubject has promoted such interoperability movements across Europe and in Israel, Japan, and Canada, and announced in June that it is setting up shop in the U.S., to bring such agreements to North America. The company works with EV Box and Ionity, a large fast-charging consortium supported by automakers in Europe. Its service includes integrating navigation directions to available charging stations within the network's apps.

The eventual goal, Hubject executives say, is for drivers not to even have to get out a credit card, but for payment to be handled automatically when the car is plugged in.