SAE approves new EV fast-charging standard

SAE International approved on 15 October 2012 a new technical standard that will, according to the global engineering group, dramatically reduce charging times for plug-in hybrid electric vehicles and electric vehicles.

SAE said the new charging standard, developed with the cooperation of more than 190 global experts representing the automotive, utilities and charging equipment business, ensures charging times can be reduced from as long as eight hours to as short as 20 minutes.

SAE charging standards

The original version of J1772™ defined AC Level 1 and AC Level 2 charge levels and specified a conductive charge coupler and electrical interfaces for AC Level 1 and AC Level 2 charging. The new revision incorporates DC charging where DC Level 1 and DC Level 2 charge levels charge coupler and electrical interfaces are defined. The standard was developed in cooperation with the European automotive experts who also adopted and endorsed a combo strategy in their approach.



Competition in EV fast charging 

The Combo standard approved by SAE has been backed by U.S. and German automakers.

The rival CHAdeMo system has been backed by Japanese automakers and has more than 1,500 charging stations in operation, most of them in Japan.

Both CHAdeMO and Combo tackle the task of fast charging through a direct current. It is different from the level one, 110 volts, and level two, 220 volts, which operate with alternating current.

The Combo and CHAdeMO connectors are different. So are their so-called protocols, or the language through which the electrical systems of the car and charger communicate, meaning you cannot just use a plug adapter to switch from one system to another.

Combo proponents say their system is superior because it combines Level 2 (220 volt) and fast-charging (480 volts or more) into a single plug, removing the need for two separate receptacles on a battery-powered car.

Charging standards to help EV industry

"This new technical standard is a real game-changer," said Andrew Smart, director of industry relations and business development for SAE International, in a statement today. "It reflects the advancements in technology within PHEV and EV engineering."

"This new standard reflects the many hours that top industry experts from around the world worked to achieve the best charging solution -- a solution that helps vehicle electrification technology move forward," said Gery Kissel, an engineering specialist with General Motors' Global Battery Systems unit and head of SAE's charging task force. "We now can offer users of this technology various charging options in one combined design."

About SAE 

SAE International is a global association of more than 133,000 engineers and related technical experts in the aerospace, automotive and commercial-vehicle industries. SAE International's core competencies are life-long learning and voluntary consensus standards development. SAE International's charitable arm is the SAE Foundation, which supports many programs, including A World In Motion® and the Collegiate Design Series™