A charging station, also known as a charge point, chargepoint, or electric vehicle supply equipment (EVSE), is a power supply device that supplies electrical power for recharging the onboard battery packs of plug-in electric vehicles (including battery electric vehicles, electric trucks, electric buses, neighborhood electric vehicles, and plug-in hybrid electric vehicles). Charging stations can theoretically be installed anywhere accessible by the electrical grid, including dedicated public charging facilities, multistorey car parks, private garages and carports, and even roadside parallel parking spots.
There are two main types of EV charging stations: alternating current (AC) chargers and direct current (DC) chargers. Electric vehicle batteries can only be charged by direct current electricity, while most mains electricity from the power grid is delivered as alternating current. For this reason, most electric vehicles have a built-in AC-to-DC converter commonly known as the "onboard charger" (OBC). At an AC charging station, AC power from the grid is supplied to this onboard charger, which converts it into DC power to recharge the battery. DC chargers provide higher-power charging (which requires much larger AC-to-DC converters) by integrating the converter into the charging station, thereby avoiding size, weight, and cost constraints in vehicles. The station then directly supplies DC power to the vehicle, bypassing the onboard converter. Most modern electric vehicles can accept both AC and DC power.
Public charging stations Public charging stations are typically found street-side or at retail shopping centers, government facilities, and other parking areas. Private charging stations are usually found at residences, workplaces, and hotels. Public charging accounted for approximately 46% of global EV charging infrastructure revenue in 2025, driven by high capital investment in DC fast charging networks, grid upgrades, and highway corridor expansion projects.
Standards Charging stations provide connectors that conform to a variety of international standards. DC charging stations are commonly equipped with multiple connectors to charge various vehicles that use competing standards.
Multiple standards have been established for charging technology to enable interoperability across vendors. Standards are available for nomenclature, power, and connectors. Tesla developed proprietary technology in these areas and began building its charging network in 2012.
Nomenclature
In 2011, the European Automobile Manufacturers Association (ACEA) defined the following terms: Socket outlet: the port on the electric vehicle supply equipment (EVSE) that supplies charging power to the vehicle Plug: the end of the flexible cable that interfaces with the socket outlet on the EVSE. The socket outlet and plug are not used in North America because the cable is permanently attached. Cable: a flexible bundle of conductors that connects the EVSE with the electric vehicle Connector: the end of the flexible cable that interfaces with the vehicle inlet Vehicle inlet: the port on the electric vehicle that receives charging power
The terms "electric vehicle connector" and "electric vehicle inlet" were previously defined in the same way under Article 625 of the United States National Electrical Code (NEC) of 1999. NEC-1999 also defined the term "electric vehicle supply equipment" as the entire unit "installed specifically for the purpose of delivering energy from the premises wiring to the electric vehicle", including "conductors ... electric vehicle connectors, attachment plugs, and all other fittings, devices, power outlets, or apparatuses".
Tesla, Inc. uses the term charging station as the location of a group of chargers, and the term connector for an individual EVSE.
Voltage and power Early standards +NEC(1999) levels Method Maximum supply Current (A) Voltage (V) Power (kW) Level 1 (1-phase AC) 12 120 1.44 16 120 1.92 24 120 2.88 Level 2 (1-phase AC) 32 208/240 7.68 Level 3 (3-phase AC) 400 480 332.6
The US National Electric Transportation Infrastructure Working Council (IWC) was formed in 1991 by the Electric Power Research Institute with members drawn from automotive manufacturers and the electric utilities to define standards in the US; early work by the IWC led to the definition of three levels of charging in the 1999 National Electrical Code (NEC) Handbook.
Under the 1999 NEC, Level 1 charging equipment (as defined in the NEC handbook but not in the code) was connected to the grid through a standard NEMA 5-20R 3-prong electrical outlet with grounding, and a ground-fault circuit interrupter was required within of the plug. The supply circuit required protection at 125% of the maximum rated current; for example, charging equipment rated at 16 amperes ("amps" or "A") continuous current required a breaker sized to 20 A.
Level 2 charging equipment (as defined in the handbook) was permanently wired and fastened at a fixed location under NEC-1999. It also required grounding and ground-fault protection; in addition, it required an interlock to prevent vehicle startup during charging and a safety breakaway for the cable and connector. A 40 A breaker (125% of continuous maximum supply current) was required to protect the branch circuit. For convenience and speedier charging, many early EVs preferred that owners and operators install Level 2 charging equipment, which was connected to the EV either through an inductive paddle (Magne Charge) or a conductive connector (Avcon).
Level 3 charging equipment used an off-vehicle rectifier to convert the input AC power to DC, which was then supplied to the vehicle. At the time it was written, the 1999 NEC handbook anticipated that Level 3 charging equipment would require utilities to upgrade their distribution systems and transformers.
SAE +SAE J1772(2017) levels Method Maximum supply Current (A) Voltage (V) Power (kW) AC Level 1 12 120 1.44 16 120 1.92 AC Level 2 80 208–240 19.2 DC Level 1 80 50–1000 80 DC Level 2 400 50–1000 400
The Society of Automotive Engineers (SAE International) defines the general physical, electrical, communication, and performance requirements for EV charging systems used in North America, as part of standard SAE J1772, initially developed in 2001. SAE J1772 defines four levels of charging, two levels each for AC and DC supplies; the differences between levels are based upon the power distribution type, standards and maximum power.
Alternating current (AC) AC charging stations connect the vehicle's onboard charging circuitry directly to the AC supply.
AC Level 1: Connects directly to a standard 120V North American outlet; capable of supplying 616A (0.71.92kilowatts or "kW") depending on the capacity of a dedicated circuit. AC Level 2: Uses 240V (single phase) or 208V (three phase) power to supply between 6 and 80A (1.419.2kW). It provides a significant charging speed increase over AC Level 1 charging.
Direct current (DC) Commonly, though incorrectly, called "Level 3" charging based on the older NEC-1999 definition, DC charging is categorized separately in the SAE standard. In DC fast-charging, grid AC power is passed through an AC-to-DC converter in the station before reaching the vehicle's battery, bypassing any AC-to-DC converter on board the vehicle.
DC Level 1: Supplies a maximum of 80kW at 501000V. DC Level 2: Supplies a maximum of 400kW at 501000V.
Additional standards released by SAE for charging include SAE J3068 (three-phase AC charging, using the Type 2 connector defined in IEC 62196-2) and SAE J3105 (automated connection of DC charging devices).
IEC In 2003, the International Electrotechnical Commission (IEC) adopted a majority of the SAE J1772 standard under IEC 62196-1 for international implementation. +IEC 61851-1 modes Mode Type Maximum supply Current (A) Voltage (V) Power (kW) 1 1Φ AC 16 250 4 3Φ AC 16 480 11 2 1Φ AC 32 250 7.4 3Φ AC 32 480 22 3 1Φ AC 63 250 14.5 3Φ AC 63 480 43.5 4 DC 200 400 80
The IEC alternatively defines charging in modes (IEC 61851-1): Mode 1: slow charging from a regular electrical socket (single- or three-phase AC) Mode 2: slow charging from a regular AC socket but with some EV-specific protection arrangement (i.e. the Park & Charge or the PARVE systems) Mode 3: slow or fast AC charging using a specific EV multi-pin socket with control and protection functions (i.e. SAE J1772 and IEC 62196-2) Mode 4: DC fast charging using a specific charging interface (i.e. IEC 62196-3, such as CHAdeMO)
The connection between the electric grid and "charger" (electric vehicle supply equipment) is defined by three cases (IEC 61851-1):
Case A: any charger connected to the mains (the mains supply cable is usually attached to the charger) usually associated with modes 1 or 2. Case B: an onboard vehicle charger with a mains supply cable that can be detached from both the supply and the vehicle – usually mode 3. Case C: DC dedicated charging station. The mains supply cable may be permanently attached to the charge station as in mode 4.
Tesla NACS
The North American Charging Standard (NACS) was developed by Tesla, Inc. for use in the company's vehicles. It remained a proprietary standard until 2022 when its specifications were published by Tesla. The connector is physically smaller than the J1772/CCS connector, and uses the same pins for both AC and DC charging functionality.
As of November 2023, automakers Ford, General Motors, Rivian, Volvo, Polestar, Mercedes-Benz, Nissan, Honda, Jaguar, Fisker, Hyundai, BMW, Toyota, Subaru, and Lucid Motors have all committed to equipping their North American vehicles with NACS connectors in the future. Automotive startup Aptera Motors has also adopted the connector standard in its vehicles. Other automakers, such as Stellantis and Volkswagen had not made an announcement as of late 2023.
To meet European Union (EU) requirements on recharging points, Tesla vehicles sold in the EU are equipped with a CCS Combo 2 port. Both the North America and the EU port take 480V DC fast charging through Tesla's network of Superchargers, which variously use NACS and CCS charging connectors. Depending on the Supercharger version, power is supplied at 72, 150, or 250 kW, the first corresponding to DC Level 1 and the second and third corresponding to DC Level 2 of SAE J1772. As of Q4 2021, Tesla reported 3,476 supercharging locations worldwide and 31,498 supercharging chargers (about 9 chargers per location on average).
Development for higher power charging An extension to the CCS DC fast-charging standard for electric cars and light trucks was being developed as of 2020, which was slated to provide higher power charging for large commercial vehicles (Class 8, and possibly 6 and 7 as well, including school and transit buses). When the Charging Interface Initiative e. V. (CharIN) task force was formed in March 2018, the new standard being developed was originally called High Power Charging (HPC) for Commercial Vehicles (HPCCV), later renamed Megawatt Charging System (MCS). MCS is expected to operate in the range of 2001500V and 03000A for a theoretical maximum power of 4.5megawatts (MW). The proposal calls for MCS charge ports to be compatible with existing CCS and HPC chargers. The task force released aggregated requirements in February 2019, which called for maximum limits of 1000V DC (optionally, 1500V DC) and 3000A continuous rating.
A connector design was selected in May 2019 and tested at the US National Renewable Energy Laboratory (NREL) in September 2020. Thirteen manufacturers participated in the test, which checked the coupling and thermal performance of seven vehicle inlets and eleven charger connectors. The final connector requirements and specification was adopted in December 2021 as MCS connector version 3.2.