【Factors affecting the charging speed of Ev charging station】Why is the charging speed of Ev charging station different? Ev charging station supplier-Besen

Besen -Ev charging station manufacturers

[Factors affecting the charging speed of Ev charging station] Why is the charging speed of Ev charging station different charging station and DC Ev charging station, we can explain separately. In terms of AC piles, most of the slow Ev charging stations or charging boxes in China use 220v AC charging, the output current is 16A or 32A respectively, and the theoretical power can reach 3.3kw or 6.6kw respectively. Considering the 10% power loss, The AC charging speed is still very slow. For example, for an electric vehicle with a battery capacity of about 20kwh, it takes 6-8 hours to fully charge the current mainstream 3.3kw AC charging method. For Tesla's 220v HPWC (High Power Wall Adapter), the output current can reach 50A and the output power is 11kw. We still don't have to think about it. This is specially designed for MODEL S, and the Tesla and the national standard interface are also not common. In line with national conditions, just take a look.

For DC piles, different from AC Ev charging station 220v voltage access, the voltage of DC pile access is 380v, and the power generally reaches more than 10kw. For example, for electric passenger cars on the market, most of the DC piles built by the State Grid are 37.5kw, and the ones built by Potevio are also above 10kw and 15kw. For an electric vehicle with a general battery power of about 20kwh, it can be fully charged with a 10kw DC pile for 2-3 hours. It can be seen that the charging speed of AC and DC can be judged only from the output power. It is said that some early electric vehicle models are only equipped with AC charging ports, so the charging speed is naturally not fast, so in the industry There is a saying of AC slow charging and DC fast charging.

This picture is provided by the registered user "I am not a hero", and the copyright statement is feedback. Therefore, for the owners who have just used electric cars, here is a simple method to estimate the charging time of the car. During the charging process of the car, wait for Ev charging When the output current and voltage are stable on the station display interface, look at the output voltage value and current value, calculate the output power, and then compare the amount of power your car is ready to charge, and you can roughly calculate the time required for charging. 2. The influence of the vehicle on-board charger During the AC charging of the vehicle, the on-board charger will participate in the current conversion process. Usually, the alternating current will be converted into direct current by the on-board charger and stored in the power battery as electrical energy. Therefore, for the design of the vehicle's on-board charger, its power needs to be matched with the AC output power, which is generally around 3.3kw. Even with a higher power Ev charging station, the output current can only be around 16A, and the charging speed is not fast. However, it is foreseeable that with the increase of electric vehicle battery power, the power of the on-board charger should be above 6.6kw in the future to ensure the user's minimum demand for charging speed. Senova's Ev charging station can reach 220V/32A. After understanding, it is known that the power of the car charger can reach 6.6kw, and the charging speed is much faster than that of the E150EV.

If the DC charging method is adopted, due to the use of a different interface from the AC charging, the DC power is directly stored in the power battery as electrical energy, without going through the on-board charger, the charging speed is naturally much faster, but in order to ensure the battery life, To avoid overcharging and overdischarging, the car factory will set the BMS (battery management system) of the vehicle power battery. For example, the charging rate of the BYD E6 operating in Shenzhen is about 0.5C (E6 charging voltage and current 326V/100A). 3. The influence of the power battery In the case of the same fixed power output from the Ev charging station, the greater the power of the vehicle's power battery, the longer the charging time. This is like a math problem for elementary school students. Filling with water, the bigger the pool, the longer it will take to fill with water. The reason is relatively simple. In addition, the energy density of the ternary material lithium battery is generally higher than that of the lithium iron phosphate battery, so for the same model, if the driving range is required to be the same, the ternary battery must be installed less than the iron lithium battery, and the charging speed will naturally be faster. Some.

There is also a phenomenon that friends in the north will feel more deeply, that is, in winter, the car cannot be charged, or the charging speed is maddeningly slow. What is going on? This is related to the chemical characteristics of the battery itself, which is the so-called low temperature protection. When the temperature is too low, the metal lithium in the battery will deposit and no longer chemically react with the substance, resulting in a short circuit inside the battery. In particular, the low temperature performance of lithium iron phosphate batteries is relatively poor. According to related materials, the capacity retention rate at 0 °C is about 60-70%, at -10 °C is 40-55%, and at -20 °C is 20-40%. %, the ternary battery is slightly better than lithium iron phosphate. In the past, some electric car users needed to drive the car out for a few laps to warm up the car to recharge. It is estimated that the electric car hot car will only happen in the northern region, but now most car manufacturers have battery heating modules. When charging and heating, and activating the battery during the charging process, the power will naturally consume a lot.

In short, the slow charging speed in winter is certain, but the solutions and efficiency of different car manufacturers will be slightly different. Car owners should ask carefully about this problem before buying a car. 4. Other influencing factors The influencing factors of electric load are mentioned here. Especially in summer, every household turns on air conditioners or other high-power equipment. When the load of the transformer reaches its peak, the voltage will drop, which will also affect electric vehicles. charging speed. However, regular residential areas are generally dedicated transformers, which have a limited impact on the charging speed, while some self-built houses, urban villages and other users generally consume electricity from regional public transformers, which has a greater impact.

Therefore, for electric vehicle users, it is recommended to choose to charge during the valley period, and the charging speed will be faster.