As the physical interface for energy transmission and information exchange between electric vehicles and charging facilities, the type, standard and compatibility of electric vehicle charging connectors directly affect the user's charging experience, charging efficiency and the interconnection of the entire electric vehicle ecosystem.
This article will discuss in detail several major types of electric vehicle charging connectors in the world, their characteristics, technical specifications and other issues to help readers better understand the current complex charging interface landscape.
1. AC charging connector
The AC charging connector is mainly used to connect the AC power of the power grid to the AC charging port of the vehicle. Currently, the two most important AC charging connector standards in the world are Type 1 and Type 2.
Type 1 (SAE J1772)
Name and Standard: Commonly referred to as the J1772 connector or J-plug, it follows the SAE J1772 standard established by the Society of Automotive Engineers (SAE).
Origin and application area: Mainly used as a standard AC charging connector in North America, Canada, Japan, South Korea and some Asian markets.
Physical Design: Type 1 connectors are circular and typically have 5 pins:
- Two large pins are used to deliver AC power (L1, N or L, L).
- One pin is used for ground.
- Two small pins are used for communication and control (Pilot Contact and Proximity Detection). The Pilot pin is used for communication between the charging station and the vehicle to negotiate charging parameters (such as the maximum allowed current). The Proximity Detection pin is used to detect whether the charging gun has been inserted into the vehicle port to ensure safe locking and prevent live plugging and unplugging.
Technical Specifications:
- Typically supports single-phase AC.
- The standard J1772 connector has a rated current of up to 80A, but in actual applications, due to the characteristics of the power grid in residential and public facilities in North America and Japan and the capacity of the vehicle's onboard charger, the common Type 1 charging power is usually between 3.3 kW and 7.4 kW (corresponding to 120V/240V voltage and different current levels, such as 16A, 32A, etc.). Although higher single-phase power can be supported in theory, AC charging exceeding 7.4 kW is not as common as Type 2 in these areas.
- The voltage range is usually between 120V and 240V AC.
Advantage:
- The design is relatively simple, mature and reliable.
- It has extensive infrastructure and vehicle compatibility in the North American and Japanese markets.
Disadvantage:
- It only supports single-phase AC power, which limits the maximum power of its AC charging and cannot use three-phase power to achieve faster AC charging like Type 2.
- The physical size is slightly larger than Type 2.
Current status: It is still the mainstream AC charging standard in North America and Japan, but globally, its position is gradually being challenged by Type 2 and its derivative CCS standard. Many vehicles entering markets such as Europe will provide Type 2 interfaces for the European market even if they use Type 1 in their home market.
Type 2 (IEC 62196)
Name and Standard: Often referred to as the Mennekes connector (named after a major German manufacturer) or IEC 62196 Type 2. Follows the IEC 62196-2 standard set by the International Electrotechnical Commission (IEC).
Origin and application area: Originated in Europe and designated by the European Commission as the official charging standard in Europe. It has become the mainstream basic connector for AC charging and CCS DC charging in many countries and regions around the world (including most European countries, Australia, New Zealand, some South American countries, some Southeast Asian countries, etc.).
Physical Design: Type 2 connectors are oval in shape, flat on the top, and typically have 7 pins:
- Three pins are used to transmit AC power (L1, L2, L3), making it capable of supporting three-phase AC.
- One pin is for the neutral line (Neutral).
- One pin is used for ground.
- Two small pins are used for communication and control (Control Pilot and Proximity Plug). Similar to Type 1, used for charging handshake and safety detection.
Technical Specifications:
- Supports single-phase and three-phase AC. This is the main difference between Type 2 and Type 1.
- When charging in single phase, the power is similar to Type 1, up to 7.4 kW.
- When charging in three phases, the power can be significantly increased. Common power ratings for home or public AC charging stations are 11 kW and 22 kW (corresponding to 400V three-phase power and 16A/32A current). In theory, the Type 2 connector can support higher current and power, but the actual charging power is limited by the vehicle's onboard charger capabilities and the grid capacity.
- Voltage typically ranges from 230V (single phase) to 400V (three phase) AC.
Advantage:
- Supporting three-phase AC power, it can achieve higher AC charging power than Type 1 and shorten AC charging time.
- Compatible with single-phase and three-phase charging, with a wide range of applications.
- It is the basis of the CCS2 DC charging standard, with one charging port designed to be compatible with both AC and DC (via CCS2).
- Widely adopted around the world, it is the standard for many new market introductions.
Disadvantage:
- The physical size is slightly larger than Type 1.
- The 7-pin design is slightly more complicated than the 5-pin design.
Current status: Dominant in Europe and many other regions, it is the fastest growing AC charging standard worldwide and an important component of the CCS DC charging standard.
2. DC fast charging connector
DC fast charging connectors are specially designed to transmit high-power direct current to enable rapid energy replenishment of electric vehicles. The main DC fast charging standards include CCS (Combined Charging System), CHAdeMO, Tesla's dedicated connector (NACS) and China's GB/T DC.
CCS (Combined Charging System)
Core concept: CCS is not a new, completely independent connector type, but a "combined" charging system that adds two high-power DC pins to the existing AC connector (Type 1 or Type 2). This means that the vehicle only needs one charging port to be compatible with both AC slow charging and DC fast charging.
Two types: CCS1 and CCS2
CCS1: Adds two large DC pins below the Type 1 (SAE J1772) connector. The AC portion is compatible with Type 1, and the DC portion transmits power through the two additional pins. The main application area is North America.
CCS2: Adds two large DC pins to the bottom of the Type 2 (IEC 62196) connector. The AC part is compatible with Type 2, and the DC part is added with new pins. The main application areas are Europe and many regions around the world that adopt the Type 2 standard.
Physical Design:
- CCS1: The top is the Type 1 circular 5-pin layout, and the bottom is two large circular pins side by side.
- CCS2: The upper part shows the oval 7-pin layout of the Type 2, and the lower part shows two large round pins side by side.
When charging with DC, the charging gun is inserted into the complete CCS port; when charging with AC, the charging gun is only inserted into the upper AC part (Type 1 or Type 2).
Technical Specifications:
Supports high-power DC charging. The power of early CCS charging piles was about 50 kW, while modern fast-charging and ultra-fast charging piles can reach 150 kW, 350 kW or even higher (such as the Porsche Taycan and other models that support the 800V platform).
Wide voltage range, up to 500V, 800V or even 1000V DC.
PLC (Power Line Communication) is used as the main communication protocol. Data is transmitted through the power line itself and is used for charging handshake, status monitoring, payment authentication, etc.
Advantage:
- The integration of AC and DC charging ports simplifies vehicle design and user use (one charging port is sufficient).
Supports high-power DC fast charging. - Based on the existing Type 1/Type 2 standards, it is easy to promote on the basis of the existing AC infrastructure.
- It has received widespread support from major global automakers and charging equipment suppliers and is currently the most mainstream DC fast charging standard in the world.
- PLC communication provides richer data interaction capabilities.
Disadvantage:
- The CCS connector (especially including the cable) is large and heavy, which may not be convenient for users to operate, especially when liquid cooling the cable is required for high-power charging.
- Two regional variants, CCS1 and CCS2, need to be distinguished.
Current status: CCS2 is the standard in Europe and most other markets and is expanding rapidly around the world. CCS1 is the dominant standard in the North American market but is facing challenges from Tesla NACS.
CHAdeMO
Name and Standard: CHAdeMO is a standard promoted by an association of Japanese automakers and industry organizations such as Tokyo Electric Power, Nissan, Mitsubishi, Fuji Heavy Industries, Toyota, etc. The name is derived from the Japanese "O CHA demo ikaga desuka", which means "have a cup of tea and take a break to charge", symbolizing fast charging.
Origin and application area: Originated in Japan, and was used in the early global electric vehicle market, especially in some Japanese models (such as the early Nissan Leaf and Mitsubishi Outlander PHEV). It has a certain market share in the world, especially in Japan.
Physical Design: The CHAdeMO connector has a very unique circular appearance, is larger in size, and contains multiple pins for high-voltage DC power transmission, grounding, and CAN bus communication.
Technical Specifications:
- Supports high-power DC charging. The first generation of CHAdeMO has a standard power of about 50 kW, and subsequent versions such as CHAdeMO 2.0 can reach 400 kW. The super CHAdeMO 3.0 is designed to support higher power and wider compatibility.
- Voltages typically range from 50V to over 500V DC.
- CAN bus (Controller Area Network) is used as the communication protocol.
- Unique advantages: The CHAdeMO standard was designed from the beginning to support bidirectional charging , which means that not only can the vehicle be charged from the grid (Vehicle-to-Grid, or Vehicle-to-Home), but also the power in the vehicle battery can be fed back to the grid or home. This is of great significance for grid stability, peak and valley regulation, and home backup power supply.
Advantage:
- One of the pioneers in the field of DC fast charging, with mature and reliable technology.
- The powerful two-way charging function is its unique selling point.
- It has a strong foundation in the Japanese market.
Disadvantage:
- In terms of global market share, many non-Japanese brands are being strongly squeezed by the CCS standard and do not provide CHAdeMO interfaces.
- The CHAdeMO connector itself only supports DC charging, and vehicles usually require additional Type 1 or Type 2 interfaces for AC charging, increasing the number of interfaces on the vehicle side.
- The physical size is relatively large.
Current status: It is still an important DC fast charging standard in Japan, but in markets such as Europe and North America, CCS has become mainstream, and the number of CHAdeMO piles and supported models are decreasing. In the future, the CHAdeMO Association is working with China to develop the ChaoJi standard, which aims to integrate and replace the existing CHAdeMO and GB/T DC to enhance international compatibility.
Tesla dedicated connector (NACS - North American Charging Standard)
Name and Standard: Originally called the "Tesla Connector", it is a unique standard developed by Tesla for its electric vehicles and Supercharger network. At the end of 2022, Tesla announced that it would open its connector design specifications to other companies and named the standard it promoted in the North American market NACS.
Origin and application area: Initially only used in Tesla vehicles and Tesla Supercharger network. The main market is North America. In Europe and other regions, Tesla vehicles have adopted CCS2 interface for DC fast charging.
Physical Design: The Tesla/NACS connector is very compact and simple in design, significantly smaller than CCS or CHAdeMO connectors. It supports both AC and DC charging with only a small number of pins (usually 5), without the need to add an additional DC pin to the AC connector like CCS. Its compact design is a major feature.
Technical Specifications:
- Supports AC and DC charging, all through the same physical interface.
- The AC charging power can reach 11.5 kW or 19.2 kW (depending on the model and charging station).
- DC fast charging has a very high power. Tesla's Supercharger network is known for its high power and stability. The latest V3 Supercharger has a power of up to 250 kW, and V4 will support higher power in the future.
- The communication protocol is CAN bus.
Advantage:
- The connector is compact, lightweight and easy to operate.
- The single charging port supports both AC and DC, which is convenient for users.
- Closely integrated with Tesla's extensive and reliable Supercharger network, it provides an excellent user experience (plug and charge).
- As NACS opens, it is expected to simplify the charging landscape in the North American market.
Disadvantage:
- Historically a closed proprietary standard that limited use on other brands of vehicles (adapters required).
- Although Tesla has opened up NACS, it will take time for other automakers and charging network providers to adopt and deploy it.
Current status: In the North American market, NACS has a large Tesla fleet and Supercharger network as its foundation. With major automakers such as Ford, GM, Rivian, Volvo, Polestar, Nissan, Mercedes-Benz, etc. announcing that they will adopt NACS interfaces in the North American market or provide NACS adapters to use the Supercharger network, NACS is quickly becoming a strong competitor to challenge the dominance of CCS1 in North America. In Europe and other regions, Tesla vehicles use CCS2.
GB/T (Chinese National Standard)
Name and standard: Follow China's national standard, specifically the GB/T 20234 series standard for electric vehicle charging connectors.
Origin and application area: Specially formulated and used for the Chinese market. China is the world's largest electric vehicle market and the GB/T standard is mandatory in China.
Physical design: The GB/T standard defines different physical connectors for AC and DC charging , although on many Chinese electric vehicles, the AC and DC charging ports are arranged on the same side of the vehicle or in adjacent positions.
GB/T AC Connector: The shape is somewhat similar to the Type 2 connector (both have 7 pins), but the pin layout, keyway and locking mechanism are different, so it is not physically compatible with Type 2. Supports single-phase and three-phase AC power.
GB/T DC Connector: This is a separate, larger, multi-pin connector specifically for DC fast charging.
Technical Specifications:
- Supports AC and DC charging.
- The AC charging power is affected by the standard and vehicle, and is usually not as high as the 22 kW commonly used in European Type 2. Common power levels include 7 kW and so on.
- DC charging has a wide power range, from a low of 50 kW to the latest ultra-fast charging standards (such as the super project launched by the High Power Charging Alliance CHAdeMO and CEC/China Electricity Council, which aims to support higher power and international interoperability), with power reaching hundreds of kilowatts.
- The communication protocol mainly uses CAN bus.
Advantage:
- It is the only official standard for the huge Chinese market, ensuring interoperability within China.
- It has a large user base and infrastructure.
Disadvantage:
- Completely independent of other mainstream global standards (Type 1/2, CCS, CHAdeMO), electric vehicles or charging piles not used in China require an adapter to be compatible.
- AC and DC use different physical interfaces (although they may be adjacent in the vehicle), rather than being integrated into one interface like CCS.
Current status: It has an absolute dominant position in the Chinese market and is the standard that all electric vehicles and charging equipment sold in China must comply with. In the future, it may merge with the CHAdeMO standard to form a new super standard to enhance international compatibility.
In conclusion
Although there are currently multiple standards coexisting, which poses considerable challenges in terms of operability, the industry is working hard to improve user charging convenience through adapters, multi-standard charging stations, and potential future standard convergence and higher-level protocol compatibility.
