When faced with an alternating current charging station, not all electric vehicles are equal in terms of recharging power. This is due to the onboard charger, which varies from one model to another. That’s why, in some situations, the 22 kW option can be very useful, especially if you are impatient. But it needs to be offered by the manufacturer…
All electric car drivers know that having range is good, but having a fast recharge speed is even better. When purchasing, it is important to check what charging power the vehicle can handle. This involves distinguishing between direct current power and alternating current power.
The former is for fast charging stations equipped with a Combo CCS connector and is mostly used during long highway trips. The latter is for all stations that use a type 2 cable, attached or not. It is just as important as the former, or even crucial depending on your usage. This recharge power depends on an essential element: the onboard charger.
What is an onboard charger?
To store energy, an electric car battery needs to be supplied with direct current (DC). For example, at a highway fast charging station, the electricity delivered is indeed direct current. The electricity is then directly injected into the battery, allowing for high charging powers. But what about a domestic outlet with alternating current (AC), for instance?
This is where the onboard charger comes in. It is a small box containing various electrical components, including an AC/DC converter that converts alternating current to direct current. It is engaged as soon as the vehicle is plugged into an alternating current power source. This includes domestic outlets, as well as many public charging stations.
Chargeur embarqué de Tesla
The power of this charger, measured in kilowatts (kW), determines the maximum charging speed it allows. It is mostly 7 or 11 kW, but can sometimes go up to 22 kW, as a standard feature or option. With this increased power, a vehicle can recharge its battery much faster.
The advantage of three-phase charging
The 11 kW and 22 kW onboard chargers are known as three-phase chargers. This means they use three phases to transport current, making them more powerful than the 7 kW single-phase chargers. However, this requires using a suitable charging cable.
With a 22 kW charger, the cable must be at least 32A (and 20A for 11 kW). This ensures that the cable is not limiting the charging power. Usually, this cable is provided with the vehicle. Otherwise, the onboard charger will operate at its maximum power, saving valuable time.
Up to 3 times faster!
For example, the Renault Twingo ZE comes with a standard 22 kW onboard charger. When plugged into an alternating current charging station delivering 22 kW or more, it takes about 30 minutes to recover 100 km of range. In comparison, a Dacia Spring with a 7 kW onboard charger would need one hour and forty minutes to cover the same distance, despite consuming slightly less energy.
This time difference can be even greater if the Dacia Spring is connected to an 11 kW charging station, which will limit the power to 3.7 kW. At this rate, it takes nearly three and a quarter hours to recover 100 km of range. Depending on usage, this time delay can feel very long…
It is worth noting that there is a scenario in which an electric vehicle with a three-phase charger will recharge slower than a model with a single-phase charger. This occurs with vehicles equipped with an 11 kW charger using a 20A cable on 7 kW stations. In this setup, the charging power will be limited to 4.6 kW (20A), while vehicles with a 7 kW charger will charge at 7 kW.
For what purposes?
When recharging at home overnight, the power of the onboard charger is less significant unless you have a three-phase electrical installation. The same applies if you only travel on highways. However, there are many cases where faster charging can be essential, especially for drivers without home charging solutions who rely on public charging stations.
For these users, faster charging is crucial, especially during errands or lunch breaks outside. It is also a significant advantage for professionals who travel regularly. With a 22 kW AC station at their destination, the vehicle can be fully charged during a 2-3 hour meeting, eliminating the need to stop at a DC fast charger on the way back. This saves valuable time.
Which electric vehicles are affected?
Unlike the 11 kW onboard charger, the 22 kW option is only available on a few electric vehicle models. Most brands simply do not offer it. Brands like Citroën, Fiat, MG, Hyundai, and Kia do not offer it. Tesla has also discontinued it, although certain versions of the Model S and Model X had it. Here is a list of all the models sold in France that have offered or still offer this feature:
If your vehicle is not on this list, it likely does not have a 22 kW onboard charger, neither as standard nor as an option. If it is on the list but you have not heard about it, it may be because the chosen version/trim did not have access to it. For more details on a model-by-model basis, check our vehicle specs.
Conclusion
In summary, the 22 kW onboard charger is an option worth considering if offered by the manufacturer. It provides convenient flexibility, especially for charging at public destination stations, significantly reducing the duration of charging sessions.
However, when not included as standard, this option comes at an extra cost. It’s essential to assess your usage to determine its profitability, especially considering that a 22 kW charger may have lower efficiency than a 7 kW charger.
Lastly, the decision to opt for this option must be made at the time of purchase, as the power of the onboard charger cannot be modified once the vehicle has left the factory. Feel free to seek advice from the community on the Automobile Propre forum if you need guidance on this matter.
What are your thoughts on 22 kW AC charging? Is it a purchasing criterion for you? Share your comments below.