The images below summarize the different AC and DC connectors:

The United States and Japan have Type 1 AC, Type 4 Chademo DC, Combo 1 AC-DC, and Tesla's AC connector.

Europe has Type 2 AC, Type 3 AC, Type 4 Chademo DC, and Combo 2 AC-DC. China has a Type 2-based AC and its own DC GB/T connector.

Regarding car manufacturers, American and European car manufacturers have adopted the CCS/Combo system, while Japanese car manufacturers have adopted the Chademo system.

This mode requires slow AC charging via a standard electrical outlet. There is no connection between the vehicle and the charging point. A ground wire for the electric vehicle and an external protection device against faults are required. In many countries, this type of charging is considered unsafe and illegal.

This mode provides slow AC charging from a standard electrical outlet. Additionally, the charging cable is equipped with an in-cable control and protection device (IC-CPD) responsible for control, communication, and protection (including residual current protection).

This mode requires slow or semi-fast charging via a dedicated electrical socket for electric vehicle charging. The charger (or charging station) has a socket specific to the electric vehicle, generally compatible with type 1 or type 2. A charging cable with an EV plug on both ends is used to connect the electric vehicle to the charger. The charging station is responsible for controlling the charging process, communicating with it, and protecting it (including residual current protection). This mode is commonly used in public charging stations and can facilitate integration with smart grids.

Mode 4 uses a dedicated electrical socket for electric vehicle charging, similar to mode 3. The charger typically has a charging cable with a plug for the electric vehicle. Mode 4 is specifically used for DC charging and is recommended for fast charging of electric vehicles. In the case of DC charging, an AC/DC converter is located within the charging station. Control, communication, and protection functions are integrated into the charging station.

There are also three charging modes depending on the location of the charging cable for the charging system.

As we saw in previous lectures, the battery is the most important part of the electric vehicle. It largely determines the cost of the electric vehicle and its range. Therefore, understanding the performance parameters of the battery is very important. It forms the basis for understanding battery charging. Let’s now take a look at some key performance metrics that we need to know:

1. 1. 1. Nominal Voltage (V nom, in V) : It is the rated voltage of the battery when fully charged. When the battery is discharged or loaded, the voltage gradually decreases to a lower value, V bat.
      2. 
         Nominal Current (I nom, in A) : It is the rated current of the battery for charging or discharging. The actual charging/discharging current is usually <= I. Furthermore, electric vehicles typically have a much higher peak discharge current than peak charging current.
      3. 
                  Enom = QnomVnom
         
         
      4. Charging/Discharging Efficiency (%): When charging or discharging a reversible battery, not all the energy sent to the battery can be effectively stored, and not all the available electric charge inside the battery can be successfully retrieved. Efficiency is used to represent the battery's ability to store/retrieve electric charge or energy. Battery efficiency is not always constant, even in a single cycle, and depends on SOC, cell temperature, and current. When we talk about efficiency, in general, we refer to the overall cycle efficiency, which means the efficiency of the entire cycle.