Is the charge always unsatisfactory in winter?

It's been a cold day recently, and it's given many electric car owners a bit of trouble, and there's not enough mileage to shrink it, and it's not always enough to charge the car's electric charge.

In the face of this situation, some owners of the tank manufacturers falsely reported mileage, battery data fraud. And ... And ...

However, the small editor has to say that this is impossible because the country has regulations for the capacitance detection of power cells in very detailed specifications. So why are there complaints?

An electric car is a disappointment.

In fact, the battery capacity we usually refer to refers to the nominal amount of electricity, which is the data obtained by multiplying the individual battery capacity by the total voltage of the battery pack.

But in fact, manufacturers will do some "small hands and feet" on the battery on the vehicle. For example, the original battery capacity is 100 %, but the real available is about 80 % -90 %.

The reason why the manufacturer does this is actually due to the safety of the battery. Because during the charging process, the battery cannot be filled too full, and it can not put the power into space. If the battery is filled with every time, it will greatly reduce its service life.

In addition, if the charge is too full, if the charging system fails, it may cause a safety accident due to "overcharging". In life, the most common example of our mobile phone is the use of some of the chargers to charge the phone.

In general, the battery management system generally reserves a certain "bottom redundancy" as a warranty. This is mainly to consider that if the vehicle is stored for a long time, there must be a small amount of residual electricity when the consumer thinks that electricity reaches 0 %.

We use the electric car's Benchmark, Tesla. For example, when the charge reaches 100 %, Tesla will retain 10 % of the charging space and can not be charged. When the battery capacity is displayed at 0 %, it will also retain 10 % of the battery. Can not release. In fact, Tesla can only use 80 % of the battery's true capacity.

Similarly, domestic car companies are similar in the security redundancy settings of power cells. Take BYD as an example. Although the core uses lithium iron phosphate power cells, it also retains 2 to 3 % redundancy at the top. At the bottom, about 6 to 8 % of redundancy is retained, and the amount of electricity retained is relatively small compared to Tesla.

Therefore, because of the redundancy of the battery, the battery suddenly removed 10 % to 20 % of the electricity. In fact, the amount of electricity that is redundant is the actual amount of electricity that the owner can use, not the nominal amount of electricity in the announcement.

Factors affecting battery power

In addition to the above reasons for the redundancy of electricity, there are actually many factors that affect the use of battery power.

When the vehicle is in a state of rapid acceleration and rapid deceleration during driving, this requires that the motor must turn faster and that the battery must supply more power. However, in fact, the larger the power consumption, the lower the voltage at the same capacity ratio. Eventually, a few percentage points of the charge wouldn't come out.

Temperature is also a big killer of batteries. Many people feel that driving a pure electric car in the winter is particularly fast. From 25 degrees to -20 degrees at room temperature, the battery output is reduced by 30 %.

Not only that, when charging at low temperatures, some manufacturers will reduce the charging current and increase the charging time to ensure the safe charging at low temperatures. From room temperature to minus 25 degrees, the charging time is increased by more than 40 %.

When driving in the winter, air-conditioning heating also requires batteries to provide energy, and it consumes about one degree of electricity in about half an hour.

Therefore, the reason why the battery cannot be filled is that the battery turns on the low-temperature protection function in a low-temperature environment. The battery consumes part of the battery to keep the battery warm, so the battery cannot be filled at all times.

The page contains the contents of the machine translation.