Low temperature causes electric cars to lie down frequently. How can we keep the battery life in winter?

At present, the most important thing used in electric vehicles is lithium-ion batteries, including three mainstream lithium-ion batteries, lithium iron phosphate, ternary lithium, and lithium manganate, with graphite materials as the negative electrode. Their basic reflection principles are similar, and they are all 'rocking chair' electrochemical energy storage processes. Macroscopically, low temperature reduces the available capacity of lithium-ion batteries while increasing internal resistance; microscopically, low temperature reduces the discharge potential of the active material of lithium-ion batteries on the one hand, and increases the discharge resistance of the system on the other hand. When the available power is reduced, the mileage will inevitably be reduced, and the increase in the internal resistance of the battery will directly convert part of the available power into ohmic heat and wasted. Then, the battery loses power, the battery life shrinks, and you drive on the road tremblingly, worrying about the vehicle lying halfway! How to deal with this situation? Keeping the battery life of an electric vehicle in a low temperature environment in winter is a 'fine job4 truths about the shrinking battery life of electric vehicles. 1. Excessive load, long time to open the air conditioner heating, resulting in excessive power consumption and shorter battery life. 2. Insufficient tire pressure leads to increased power consumption. When the tire pressure is too low, more power will be consumed to overcome the driving resistance, resulting in increased power consumption during driving and shortening the cruising range. 3. Not preheating before driving will speed up power consumption and reduce battery life. In the few minutes before the start, it is best to be able to drive at a constant speed and slowly. Because the temperature of the coolant needs a process to ensure the normal operation of the battery. Data shows that a preheating measure can bring about the following level of mileage improvement: the ambient temperature is minus 20℃, no preheating, start driving directly, the driving range is about 60% of the normal temperature mileage; using the preheating method, the continuous driving range Increase to 90% of the mileage at room temperature. 4. Frequent braking and starting lead to increased power consumption. Similar to traditional cars, the consumption of electricity on congested roads in cities will increase. Sudden acceleration and sudden braking will cause excessive instantaneous current, which not only consumes electricity, but also affects the service life of the motor. In addition, in addition to the above four factors, the parking environment affects the battery life of electric vehicles in low-temperature environments. Due to the difficulty of parking in the city, in order to save costs, many car owners often find a place to park downstairs, which usually has no effect, but when the temperature is relatively low, the vehicle is particularly prone to loss of electricity. At the same time, long-term idleness will also cause electric vehicles to lose power, which will affect battery capacity and battery life. It is reported that a northern car owner tested it and drove the car to a high-end shopping mall. The instrument panel in the car showed an ambient temperature of 5°C. When viewed the next day, the display temperature changed to 19°C. The 16-hour battery life and power remained unchanged. Therefore, a relatively warm place can preserve the power of electric vehicles, but this is also a more realistic difficulty for many people. Low-temperature operation is very harmful to lithium-ion batteries. It is best not to operate at low temperatures, including discharging and charging. Discharge at low temperature will cause damage to the structure of the positive and negative materials, which in turn will cause permanent loss of part of the available capacity. Low-temperature charging is more harmful. For batteries that have experienced low-temperature charging, the probability of thermal runaway increases several times. The important influencing factor is the lithium metal deposition accumulated by low-temperature charging, which is more active and more prone to violent reactions.