The "virtual" that comes out of the mouth of Chinese medicine may not be so terrible, but the other kind of "virtual" should be paid attention to, and sometimes you still want to slap the backhand.
For example, buying an electric car to go home, driving for a year found that the battery capacity is left at 92%...
Frightened, I quickly looked at my one-year-old apple, fortunately, the maximum capacity is 93%, and it feels quite durable.
Back to the point, here's the thing.
An overseas blogger bought an electric car, drove 15,000 kilometers in 3 months, and after driving more than 20,000 kilometers in 1 year, found that the battery capacity was not as high as before. The blogger also tried his best to record and test, and the results were not satisfactory.
However, his usage habits are not too good, and the owner basically charges the car with a DC fast charge of 100kW, and almost always charges it when the power is less than 10%.
Frequent use of fast charging, and waiting until the power is urgent to start charging, is indeed an important reason for aggravating battery loss.
With this, the professor mainly wants to discuss how the problem of battery attenuation actually arises, or how it is defined.
By the standards of our country.
At present, the country basically uses the battery attenuation to 80%, that is, the attenuation of 20%, as the limit of the battery "retirement", because below 80%, the attenuation may accelerate sharply, affecting normal use.
After all, the battery is the most core component of the tram, in case it is not good, it is easy to cause "public anger".
Once the ideal ONE changed the warranty content, the "power battery pack power decayed by 20%, for the owner to repair or replace the power battery pack" in the battery life threshold, increased by 10%, that is, attenuation of 30% before the owner to repair or replace the power battery pack.
This change has caused a large wave of dissatisfaction among ideal ONE car owners, which is a more rational response.
Like an overseas Tesla owner some time ago, the car had a problem, and Tesla said it would spend about 143,300 yuan to buy a new battery pack.
As a result, he blew up his model S in protest, using 30 kilograms of explosives.
Whether it is a show or a real upset, Tesla has given a statistic in 2021: Tesla has about 90% of the battery capacity of its electric vehicle after driving 320,000 kilometers.
And this is exactly what Tesla came up with based on the battery performance data of the Model S and Model X.
In short, Tesla wants to show that the design life of the battery pack is longer than the car itself, and it can also reach the mileage of a fuel car to scrapping, so there is no need to worry about the problem of replacing the battery.
That's what Tesla said, not what I said.
An overseas company called Geotab also came to a survey conclusion by collecting data on the use of nearly 6,000 electric vehicles around the world: pure electric vehicles will attenuate by an average of 2.3% of electricity per year.
For example, the battery capacity of the 2015 Tesla Model S is attenuated by an average of 2.3% per year, and the battery capacity of the 2015 Nissan Leaf is attenuated by an average of 4.2% per year...
These data are also a reference standard for testing whether the attenuation of an electric vehicle is too fast.
Very real problem, lithium battery attenuation is an inevitable process, resulting in many reasons, may also be the negative capacity design is not enough and so on.
Capacity decay exhibits behaviors such as voltage reduction and insufficient capacity. Put on the car, that is, the power is worse than before, and the endurance is lower than before.
If you really want to break the casserole to ask the end: Why does the lithium battery decay?
The charge and discharge of lithium batteries is done by the movement of lithium atoms between the positive and negative electrodes. Every time the lithium atom completes a charge and discharge cycle, that is, after the full charge is discharged, the electrode structure will change, and this change will lead to a decrease in the performance of the battery after accumulating over time, that is, battery attenuation.
This is actually the same as tire wear, as long as it starts, it will produce wear; the more intense the driving, the harsher the environment of use, and the wear will be correspondingly aggravated.
So if you feel that the battery is attenuated, what should the more professional battery capacity method test be?
The first is to use professional equipment to calculate the usable capacity of the power battery during vehicle testing by monitoring dynamic data such as charging voltage, current and charging power, as well as the amount of change in the power battery SOC, and compare it with the nominal capacity of the system.
There are also two types of testing methods: interval testing and depth testing.
For example, the in-depth test is to drain the power battery, and then use the fast charge mode to fill the charge, and calculate the usable capacity of the power battery through the monitored data. Depth testing will be more accurate than interval testing.
In fact, the problem of serious battery loss is related to battery technology. For example, volkswagen ID.3 battery suppliers at home and abroad are different, using LG batteries overseas and Ningde era batteries at home.
Foreign countries do have problems related to the battery loss of overseas Volkswagen ID.3, but there are very few in China.
After all, the Ningde era is already the pride of our national enterprises, the current leading leader in the battery industry, the global installed capacity market share of 31.8% in 2021, ranking first, far exceeding the 20.5% of LG new energy.
Finally, I would like to say that there is indeed a very big difference between the purchase of electric vehicles and the subsequent use of fuel vehicles, and the problem of endurance or loss is also closely related to your car habits and environment.
This is a problem that is difficult to avoid at present, so you hope to buy an electric vehicle user, be sure to confirm whether you can bear the corresponding results, do not be carried away by the advantages of "electric vehicles are cool, low cost of the car".