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Overview of Charging Modes

What are the different charging modes for EVs?
Top view of a signage set up in the ground of an electric vehicle charging station.
© Freepik

The international standard ‘IEC 61851-1’, entitled ‘Electric vehicle conductive charging system’, plays a crucial role in establishing guidelines for charging electric vehicles (EVs) worldwide. The standard defines four different charging modes that provide a framework for understanding and implementing EV charging infrastructure.

These charging modes serve as key reference points for charging station manufacturers, electricity utilities and EV owners, ensuring compatibility and standardization across different charging systems. By delving into the details of these four charging modes, we can gain a comprehensive understanding of the options available for charging EVs in a consistent and reliable manner.

The international standard ‘IEC 61851-1’ (Electric vehicle conductive charging system) defines four charging modes.

  • Mode 1 – Standard socket outlet
  • Mode 2 – Standard socket outlet with an AC EV charger
  • Mode 3 – AC EV equipment permanently connected to an AC supply network.
  • Mode 4 – DC EV supply

Modes 1 to 3 make use of alternating current (AC).

  • AC level 1, which considers single-phase AC chargers below 1.92 kW;
  • AC level 2, which is a single-phase charger up to 2.4 kW; and finally,
  • AC level 3, which covers chargers with either a single-phase with 3.6 kW, three-phase chargers with 22 kW or even 40 kW with increased current.

Mode 1 charging lacks communication between the grid and the vehicle and is therefore banned in the EU and many other countries. Mode 2, on the other hand, requires additional attention. This is because an electric vehicle must adhere to programmed electronics designed to protect its batteries during charging. That’s why it’s advisable to use a recommended charging mode for public charging. This mode allows extensive communication between the vehicle and the charger, which increases safety measures.

In addition, the power of Mode 2 chargers needs to be higher for public charging and is therefore a domestic charging issue. The limited power of Mode 2 and 3 chargers is associated with long charging times. These modes are therefore mainly used for overnight charging of smaller vehicles such as cars. A powerful mode 3 charger can also be used for depot charging of E-Buses.

Electric car connected in a charging station with a 3 phase 3 AC charger Mode 3, 3 Phase-AC-Charger. EC&M (2022)

Electric car connected in a charging station with an 1 phase AC charger Mode 2, 1 Phase-AC-Charger. Amazon (n.d.)

Electric bike connected to a 1 phase AC charger Mode 2, 1 Phase-AC-Charger. Raab, T. (n.d.)

Mode 4 charging – High power DC charging

Charging mode 4 uses a high power external AC/DC rectifier compared to the vehicle’s internal inverter, resulting in a higher charge power and consequently a shorter battery charge time. Effective charge control is achieved through extensive communication between the charger and the vehicle.

The electrical infrastructure leading up to the charger must be independent and equipped with appropriate overload, short circuit, differential, and grounding protections. Although this infrastructure is more extensive and costly, it allows faster charging due to the increased power capacity of the charger. It’s important to note that the maximum charging power is limited by the technology and capacity of the vehicle’s battery. While DC chargers can deliver power up to 400 kW and 1000 V, there are currently no vehicles that can take advantage of this capability.

High-power charging systems allow for rapid charging sessions, with the ability to reach 80% battery capacity in as little as 20 minutes. These fast charging speeds are essential for long-distance travel, whether for cars or trucks, and play a key role in enabling opportunity charging in public transport.

4 charging points in a parking lot, showcasing an 1 DC power charger each one Mode 4, 1 DC-Power Charger. CDE (2023)

Induction and pantograph charging

In addition to cable charging, there are two other wireless charging technologies: Inductive and pantograph charging.

Inductive charging:

Inductive charging uses magnetically coupled inductors for wireless transmission. Inductive charging would allow energy to be transferred while the vehicle is in motion, creating electrified roads. However, this is a costly technology. It is more likely that inductive charging will be used in car parks to remove the need for plugs, or at bus stations to allow buses to charge on the fly when they stop. This creates additional charging stops for buses and is feasible as the process can be fully automated without the involvement of the bus driver.

Pantograph charging:

Pantograph charging uses two catenary lines positioned above the road, with a current flow mechanism similar to that used in train catenary systems. However, road vehicles require two lines for this arrangement. As with induction charging, pantograph charging can be carried out when the vehicle is stationary or in motion.

Electric bus in the streets in a city with a pantograph charging, which means two catenary lines above de street E-Bus equipped with a pantograph charging system. Technische Universität Wien (2018)

Charging times of the charging modes

The E-Mobility industry is actively working to increase battery capacity and vehicle range. This implies an increase in charging times or charger power levels, which are expected to be 350-400 kW for Mode 4. These levels are far from those expected in non-industrialized sectors, so equipping power plants or charging stations will require upgrading electrical transmission and distribution components and work on grid stability.

Charging time increases linearly with battery capacity and decreases linearly with charging power. This means that in order to maintain a constant charging time, the charging rate must double when the capacity is doubled.

This constant change in the charging infrastructure for electric vehicles has changed the role of electricity companies in its development, who are increasingly involved in the installation of new charging stations in both the public and private sectors.

From left to right, in the diagram below, you can see the energy sources for charging an EV, ranging from the slowest to fastest. The slowest is the household plug, and the fastest is the public fast charging station.

Diagram that showcases the time that each charging infrastructure needs for an EV to be completely charged, including a household socket, household socket with a wallbox, public charging station and a public fast charging stationClick to expand

Difference in charging time per charging source. PEM Motion (2022)


To establish a robust charging infrastructure in urban areas, a variety of charging options is essential. Home charging can often be adequately addressed with a Mode 2 or lower power mode. However, in urban areas where people park for shorter periods of time, Mode 3 charging stations will be required. Similarly, larger vehicles such as buses and trucks that are charged at depots also require these more powerful Mode 3 chargers.

The shortest charging time is achieved with a Mode 4 DC charger, which allows long-distance driving and charging of trucks on the road.

Pantograph and inductive charging enable automatic on-demand charging for urban vehicles such as buses, whether stationary at a bus stop or moving along a defined route.


  • Chilean Ministry of Energy Electromobility Platform – How to characterize electric car chargers. (n.d.) Retrieved from: Link
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