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On the other hand, CCS standards, including Combo 1 and 2, are capable to facilitate both AC charging, including level-1 and level-2 charging, and DC charging. It was developed by several European and US car manufactures in around 2012. Society of Automotive Engineers (SAE) and European Automobile Manufacturer’s Association (ACEA) strongly supported this initiative with the main purpose of facilitating both AC and DC charging with only single charging inlet in the vehicle. CCS is able to facilitate AC charging at maximum charging rate of 43 kW and DC charging at maximum charging rate of 200 kW with the future perspective of up to 350 kW [22]. CCS chargers are currently installed mainly in Europe and the USA with approximate numbers of 2500 and 1000, respectively. Tesla Supercharger uses its own charging standard. Currently, Tesla Supercharger includes multiple chargers that are working in parallel and able to deliver up to 120 kW of DC charg- ing [23]. Tesla Superchargers are currently installed in about 800 stations, having about 5000 superchargers in total. Other charging method for PHEV and BEV includes inductive charging, which is conducted wirelessly. The electromagnetic induction is created by the induction coil, which is charged with high-frequency AC. The generated magnetic field will induce the vehicle-side inductive power receiver; thus, the electricity can be transferred to the vehicle. Inductive charging uses the family of IEC/TS 61980 standards. The application of inductive charging is potential to eliminate the range anxiety, as well as reduce the size of battery pack. However, there are some technical barriers in its application, especially related to lower efficiency, slower charg- ing rate, interoperability and safety. 3. General charging behaviour of electric vehicles In general, PHEVs and BEVs adopt lithium-ion battery for energy storage due to high energy density, longer charging and discharging cycles, lower environmental impacts and more sta- ble electrochemical properties [24]. In general, charging and discharging of lithium-ion batter- ies are greatly influenced by the temperature. According to literatures [25, 26], lower rates of charging and discharging occur under relatively lower temperature. This is due to the change of interface properties of electrolyte and electrode such as viscosity, density, dielectric strength and ion diffusion [27]. Furthermore, the transfer resistance also increases, which could be higher than the bulk and solid-state interface resistances, as the temperature decreases [28]. Aziz et al. [14] have performed a study to clarify the influence of ambient temperature or season to charging rate of PHEV and BEV. The study was performed during both winter and summer, using CHAdeMO DC quick charger having rated power output of 50 kW. In addi- tion, Nissan Leaf having battery capacity of 24 kWh was used as the vehicle. The results of their study are explained below. Figure 1 shows the obtained charging rate and battery state of charge (SOC) under differ- ent seasons. Although the rated output capacity of the quick charger is 50 kW, the realized charging rate to vehicle is lower, especially during winter. Charging during summer (higher ambient temperature) leads to higher charging rate; therefore, shorter charging time can be Hybrid Electric Vehicles68