Daily AUTO: In recent years, the penetration rate of electric vehicles has been continuously improved, and the penetration rate of new energy models in the current market has reached 20%, and the ownership of electric vehicles in the mainland has also risen rapidly to tens of millions. Although the continent is vast and the temperature varies greatly from place to place, after entering the winter, with the temperature decreasing, especially in the vast area north of the Huai River, the temperature may be as low as minus forty degrees, which will have a certain impact on the use of electric vehicles. The charging time of electric vehicles will be extended, and the driving range will be shortened. This is mainly because under low temperature conditions, the electric vehicle battery pack in the low temperature environment is a good container for water, when not in use, the water here will not be less. When the temperature decreases, some of the water freezes, and the available water naturally decreases. During use, if the temperature rises, the ice becomes water and can be used again. If the temperature has been at a relatively low level, then the available water is only the remaining part of the unicyed water. On the other hand, the lithium-ion power battery characteristics used by the mainstream electric vehicles in the market, in the winter low temperature environment, the electrolyte inside the lithium-ion power battery will become viscous, the speed of lithium ion movement in the middle will slow down, and the chemical reaction of the power battery of the electric vehicle will become slower, resulting in a decrease in performance and a decrease in charge and discharge. In addition to the low temperature will cause the performance of the battery to decrease, causing the mileage to shrink, it may also cause damage to the battery. Studies have shown that in an environment below 0 ° C, lithium-ion batteries are charged or discharged at high power, which will precipitate metallic lithium on the surface of the battery anode, and this process is irreversible, which will cause permanent damage to the battery. Some analytical data say that the capacity of ordinary lithium batteries will be reduced by 20% at zero degrees Celsius, and when it reaches minus 10 degrees Celsius, the capacity may only be about half. And the lower the temperature, the more it decays.
So, how to use electric vehicles in winter to reduce the impact of power battery attenuation? This news consults experts and summarizes the precautions for using electric vehicles in winter and low temperature conditions, so as not to damage the vehicle and affect the overall service life of the car.
First of all: try to "keep warm" electric vehicles. Since the power battery is attenuated because of low temperature, then as long as the temperature is raised, it can not reduce the impact. We can start from these aspects: First: try not to park outdoors, the temperature outside in winter and the temperature inside are very different. If conditions permit, it is best to park indoors; if there is no indoor parking environment, the vehicle should be added to the car coat when parking. Two: do not charge in the outdoor open air, the temperature is low, the charging efficiency will be reduced, and it may cause damage to the battery. If conditions permit, you can choose to charge indoors, or during periods of higher temperatures. Three: The air conditioning temperature should not be set too high, so that you can save power. When driving, I'd rather wear more clothes than lower the temperature setting.
Second: timely charging. In winter, the endurance of electric vehicles has dropped seriously, and it is necessary to use more snacks when using the car, and plan the charging plan in advance when traveling, so as to replenish the power faster. To minimize the use of electric vehicles for long-distance travel, the mileage is reduced too much, and the chance of anchoring in the middle of the road will increase. It is best to charge the car immediately after each use, when the power battery temperature is higher, and the charging efficiency will be relatively large. When charging, it is recommended to use slow charging, select a small current (that is, slow charging) to charge the lithium-ion battery, and fully shelve the lithium-ion battery after charging, which can ensure that the metal lithium precipitated by the negative electrode can react with the graphite and re-embed it into the graphite anode, reducing the possibility of battery damage. This will charge more and will not damage the power battery. If you don't drive for a long time in winter, it is best to charge it every three days, which is very important to keep the car battery active.
Third: develop good driving habits, when driving an electric vehicle, it is recommended that the air conditioner adopt ECO mode, try to maintain a smooth driving, less sharp acceleration, less sharp braking, and more use of economic mode (EOC mode) and high energy recovery mode. When driving in winter, you can take a low-speed and slow driving method for a few minutes to gradually heat up the battery, thereby stimulating the battery activity, increasing the discharge, and thus extending the driving range. Second, choose a smooth drive. The sharp acceleration will put the battery in a state of high current discharge, and some of the electrical energy will be converted into heat consumption, which will affect the driving range. At the same time, the battery often discharges at a large current, and the possibility of damage to the internal structure will be greatly increased. Therefore, when using the car, smooth driving can reduce the energy consumption of the whole vehicle and extend the driving range. If you suddenly switch from driving a fuel vehicle to driving a pure electric vehicle, the driving experience on ice and snow roads is particularly different, because the latter is more prone to slippage, even if it is a pure electric vehicle of more than 100,000 yuan, which is determined by the characteristics of the motor. From the characteristics of pure electric vehicles, the motor can output maximum torque from 0r/min, if the road conditions are poor, compared to fuel vehicles, pure electric vehicles are more likely to slip, which is especially obvious in winter ice and snow pavement. Therefore, for pure electric vehicles, the start and speed of the slippery road must be stable, not fast, and the most common scene is when starting at a traffic light or when the vehicle is turning, it is more important to pay attention to smooth driving and ensure safety. In addition, appropriately increase the tire pressure. Affected by thermal expansion and contraction, the tire pressure will decrease in winter, increasing the rolling resistance of the wheels, so that the energy consumption of the whole vehicle will rise and shorten the mileage. Therefore, in winter, it is necessary to check the tire pressure frequently and try to keep the tire pressure within the specified range.
Fourth, make good use of car air conditioning. People, always moving closer to the comfort mode, cool when it is hot, and heat when it is cold. Winter heating demand energy is greater: heating /cold consumption is mainly determined by temperature differences, winter -10 °C 20 °C, heating demand 30 °C. Summer 35 ° C 25 ° C, refrigeration demand is also 10 ° C and the passengers of fuel vehicles are also afraid of cold, why do not feel that winter heating is more fuel-intensive? The reason is that the engine work generates a lot of heat, which is enough for the use of a family car. When the electric vehicle works, the battery and the motor are very "calm", and there is no waste heat available; on the other hand, the heating of electric vehicles is usually achieved by the PTC of "electric energy conversion heat", and the efficiency is relatively low; the power of electric vehicle air conditioning heating is very high, up to 6KW or more, which can consume a lot of electrical energy, and the "missing" part of the mileage in the winter is used to heat the temperature in the carriage. Therefore, it is necessary to rationally use the internal and external circulation and lower the temperature of the air conditioner to save electric energy.
Summary: Lithium battery nature "afraid of cold", winter electric vehicle power decline is a relatively normal scientific phenomenon, most of the electric vehicles for urban short-distance travel use, for the current market mainstream mileage of vehicles, as long as the scientific and reasonable use of cars, safely through the cold winter, generally less likely to appear insufficient power situation.