What is the Combined Charging System (CCS) Standard?
Easy access to charging infrastructure is a key enabler of electric vehicle (EV) adoption. The EV charging ecosystem, comprised of EV manufacturers, EV charging station manufacturers, and EV charging network operators among others, understands that interoperability made possible by standards and protocols for EV charging and communications is essential to everyone’s success.
In developing the Combined Charging System (CCS) standard, the industry intent was that one style of connector (plug and port), supporting both AC and DC charging, could be used by all EV and electric vehicle service equipment (EVSE) manufacturers to ensure interoperability across the EV charging ecosystem.
When was CCS developed?
SAE International (Society of Automotive Engineers) and the European Automobile Manufacturing Association (ACEA) proposed the Combined Charging System (CCS) standard in 2011. CCS combines the existing J1772 standard connection for Level 1 or Level 2 AC-powered EV charging with a two-pin connector for up to 350MW of DC-powered fast charging. Seven automotive manufacturers (Audi, BMW, Daimler, Ford, General Motors, Porsche, and Volkswagen) agreed to adopt the combined plug standard, with the first prototype implementation demonstrated in May 2012.
What are CCS “combo plugs”?
The CCS Combo 1 (CCS1) connector uses the standard U.S. SAE J1772 plug and inlet for the U.S. 1-phase AC connection. CCS Combo 2 (CCS2) uses the EU-style of plug and inlet for a 3-phase AC connection. Both CC1 and CC2 use the same style connector for DC-powered charging. The CC1 and CC2 plugs and inlets are the same size and shape.
What else does CCS standardize?
The CCS standard covers several aspects of EV charging in addition to AC and DC charging, including communications between the charging station and the vehicle, load balancing, authentication and authorization to charge, and the vehicle coupler (the connector at the end of the charging cable, and the corresponding inlet in the vehicle). These standards are common across CCS1 and CCS2. High-level communications are based on the ISO 15118, including bidirectional communications and “plug and charge.”
What countries have adopted the CCS standard?
North American and European EV manufacturers are the leading drivers of CCS adoption, along with the industry-sponsored, non-profit organization CharIN.
- Through 2023–2024, CCS1 will remain the predominant standard for non-Tesla EVs and EV charging networks in North America (U.S. and Canada). CCS1 is also available in Central America, Korea, and Taiwan.
- CCS2 is the predominant standard in Europe and is required by the EU for EV charging networks. CCS2 is also used in Greenland, Iceland, South America, South Africa, Arabia, India, Singapore, Taiwan, Hong Kong, Oceania, and Australia.
For countries where no standard has been selected, CharIN is recommending CCS2. CHAdeMO was the original DC rapid-charging standard and is still in use in Japan and by the Nissan Leaf and a handful of other models. CHAdeMO plugs and CCS plugs are not compatible. Some charging networks in the U.S. offer CHAdeMO connectors, but support is largely being phased out.
What impact will the Tesla-developed North American Charging Standard (NACS) have on CCS adoption?
The short answer is that both NACS and CCS will co-exist in the North American market for many years, with both Tesla and non-Tesla EV charging networks supporting both standards.
The EV charging standards landscape in the U.S. has been undergoing significant change since November 2022. That’s when Tesla announced it was opening is proprietary charger connection technology to use by anyone, naming it the North American Charging Standard (NACS). NACS offers both AC and DC charging in one compact plug, using the same pins for both, and supporting up to 1MW of power on DC.
Tesla’s dominance in the U.S. EV market and its buildout of the most extensive DC EV charging network in the country makes NACS the most commonly used standard. In mid-2023, Ford, General Motors, Rivian, Volvo, Polestar, and Mercedes-Benz announced that they would equip EVs for the North American market with the NACS charge port beginning in 2025. Others may follow. These moves ensure that NACS will maintain market leadership in adoption.
However, CCS will not disappear in North America any time soon. For one thing, there are over a million CCS-equipped EVs on the road in the U.S. that will be in service for a decade or more. More importantly, EV charging networks in the U.S. must support CCS to qualify for a share of the $7.5 billion in federal infrastructure funding earmarked for EV charging.
In response, Tesla pledged it would open 3,500 new and existing Superchargers along highway corridors to non-Tesla vehicles by late 2024, qualifying for subsidies to get this done. At the same time, existing U.S. EV charging networks will continue supporting CCS and competing for federal funds — while adding NACS support to their networks to serve a large and growing marketplace.
In Europe and many other countries, CCS2 adoption predominates, fulfilling the vision of interoperability across EVs and EV charging equipment. In Europe, even Tesla EVs and chargers use CCS2, even though the Tesla charging network was until recently closed to non-Tesla drivers.
In the U.S. and North America, although two standards live side-by-side, the public EV charging providers are committing to an approximation of interoperability by supporting both standards at their facilities. That results in a win for EV drivers, who get more choice and broader access to charging.