Electric vehicles can be charged through either AC slow charging or DC fast charging. But whether it is AC or DC charging, the input and output of the battery are all direct currents. The problem is where AC can be converted into DC, either at the charging station or in the car’s converter. The household socket is AC, but the charging station can be AC or DC. All electric vehicles, even hybrid vehicles, have a built-in converter called an OBC (on-board charger). It converts AC into DC and then charges the battery.
The main difference between electric vehicle AC charging and DC charging is the charging speed. The converter in the charging station is larger, so it can convert to AC power faster than the on-board charger.
According to the International Electrotechnical Commission (IEC), the IEC 61851 standard specifies four charging modes for electric vehicles.
Mode 1 involves charging electric vehicles directly with the normal current sockets without using special safety systems. It is commonly used for charging electric bikes and scooters. In public areas, this mode of charging is prohibited.
Mode 2 refers to charging through a household electrical outlet like Mode 1 or industrial sockets, but it has a control and safety device called an in-cable control and protection device. Compared to Mode 1, it supports overcurrent and over temperature protection.
Mode 3 :The AC charging station is permanently connected to the AC power network and has control and guidance functions. With Mode 3, charging is ‘controlled’: the car and charge station communicate, and the socket will only pass voltage once the car determines a suitable charging current.
A Mode 3 charge point can supply much more power: 3.6 kW (230V/16A) or more with 1 phase through to 22 kW (400V/32A) with 3-phase charging. An EV with a more powerful converter – such as a Tesla Model S (11 kW or optionally 16 kW) – will therefore charge faster in Mode 3.
In Mode 4, the conversion from AC to DC occurs at the charging station, which means that this is the only mode involving DC charging. This charging mode requires a current converter external to the vehicle to which connect your charging cable. Its power output is much higher, exceeding 150 kilowatts. In this mode, there are two prominent charging standards – CHAdeMO and CCS. Charging stations that charge in mode 4 allow charging up to 200A and 400V even if the legislation does not specify a maximum limit.
2. What is CCS charging?
Combined Charging System: Charging connection system for Type 1 and Type 2, which allows both AC charging and DC charging with just one vehicle charging inlet.
CCS is a new energy vehicle charging standard used in Europe and America, also divided into CCS1 and CCS2. The United States is CC1, while Europe is CCS2.
The main difference between CCS1 and CCS2 is still in the charging plug, as shown in the following figure.
Here we’d like to show detail pins of CCS1 socket:
CP: Control pilot: Signal contact or signal line in a Type 1, Type 2, and GB/T charging cable. Used to transfer control information between the charging station and the vehicle. CS: Connection switch: Signal contact or signal line in the Type 1 charging cable. Notifies the charging station when the locking lever on the charging connector has been operated so that the charging station interrupts the charging current.
3. What are the advantages of CCS ?
With just one vehicle charging inlet, you can charge your vehicle with both AC and DC. There are savings in components, space, and costs for vehicle manufacturers. With actuator interlocking and temperature monitoring, the highest level of safety is ensured Global acceptance and prevalence.
4. What are the charging levels?
The charging LEVEL refers to the voltage and power of the charging system. The higher the voltage the higher the power the system can deliver and thus the quicker it will charge.
The Society of Automotive Engineers specifies the following levels in the J1772 standard:
Level 1 is limited to 120V and 1.8 kW and delivers basic charging.
Level 2 is defined as 208V to 240V and up to 80A, with a maximum output of 19.2 kW. As OEMs increase battery sizes, they are also increasing the power level within this band. Typical BEVs today can take 11 kW of AC power via their onboard chargers. Homes with three-phase power installed can reach 11 kW with 16A of current, while a single-phase power source would need to supply about 48A.
Level 3: DC Level 1 and 2 provide fast charging and are only available at commercial stations. DC Level 2, commonly referred to as simply “Level 3,” can provide up to 1,000 VDC and is projected to reach 500A in the future, with a power output of more than 350 kW. This rate can charge about 80 per cent of a typical EV battery in as little as 20 minutes.
Overall, electric vehicles can be charged in four main ways: AC Level 1/2, DC fast charging, Tesla’s Supercharger network or CCS charging. CCS is a type of DC fast charging that offers high power and 100% compatibility among the different EV brands. It also has many advantages such as quick charge-up times and wide availability of charging points. Furthermore, there are three levels of EV charging power: AC Level 1/2 offers 3-7 kW of power, DC fast chargers offer 50-150 kW and even go up to 350 kW. Taking all this into consideration, it is clear that CCS charging offers more flexibility to EV owners since it provides them with higher speeds for quicker.
If you have any more questions about EVs lithium battery solutions or want suggestions on which might be the best choice for you, get in touch with us today!
Contact Bonnen Battery↓ now and learn more about EVs lithium battery Technologies!