First, first, it is necessary to clarify the concept of needle test. National “Electric Vehicle Power Battery Safety Requirements” 2015 edition (old national standard) and 2020 edition (new national standard), the purpose, standards and test methods of acupuncture tests are totally different.
From the beginning of the lithium battery, the acupuncture test is the most important means of battery safety test. Today, in the lithium battery for more than 300 tests, it is recognized that the most stringent is still acupuncture test.
The acupuncture test is one of the mandatory detection standards in the old national standard. However, because this test is too harsh, only a few companies in the industry can pass, most companies cannot pass, on January 24, 2018, the Ministry of Industry and Information Technology issued a new national standard for comment, canceled the monomer battery Acupuncture test requirements.
The new national standard was officially implemented on January 1 this year, and new energy vehicles that do not meet the new national standard will not be able to enter the Industry and Information Technology Directory, and cannot be officially launched. This also means that since January 1 this year, most of the mainstream brands can realize the heat-spreading protection and control of the three-dimensional lithium battery heat, and only the magazine battery can pass. (It is understood that after the implementation of the new national standard, the new Industry and Information Directory, the electric vehicle of the three-yuan lithium battery can meet the requirements of the new national standard, not only the Guangzhou Automobile family)
There is no battery cell in the new national standard. It is only one of the recommended methods of testing the thermal spread of the battery system in the new national standard. The other recommended method is a heating method. The purpose of acupuncture test in the new and old national standard is different. The difficulty is different. It is different for investigation. One is a mandatory standard. One is only a test method, and it cannot pass the results of the new national standard. If I can use the old national standard needle. Test.
The new national standard actually recognizes that the battery can happen, and it has also recognized that everyone is hard to solve the thermostat of the three-dimensional lithium battery. The real inspection indicator of the new national standard has changed to “escape time”, that is, after the battery is thermal out of control, the occupant leaves no less than 5 minutes of escape time. In January 2021, the electric car is on the 100-person meeting, BYD has appealed. Extend the national standard escape time standard to 30 minutes.
Second, the magazine battery has indeed progressing in the battery pack system to prevent thermal diffusion, but the bomb is bomb, the is the case, the bomb is safe, but is it separate? As the bomb of the battery, the thermal out of control is not resolved (the temperature of the tunnel is 686 degrees after the tunnel “is 686 degrees), or an ammunition that happens at any time. Moreover, the battery system has an aging and failure risk, which is basically not resolved, and the risk is still very large.
Third, the core of battery safety is the battery, and the magazine should imply the whole package, not the battery cell. , Obviously stealing concepts. In the release of the video, because it is a battery pack, it will not be seen whether the steel needle really pierces the battery cell, whether it is tied. If there is really powerful, why not open the battery pack, take it out, take out, like BYD, do the needle test of the battery? Why steal the concept, confuse two completely different standards? It’s really strength to take the old national standard, take the monobi bare thorn of the magazine battery, so there is really convincing.
Fourth, Guangqi did not explain the positive material of the magazine battery, is it 523, 622 or an 811 battery? The positive material of the three-dimensional lithium battery is divided into 811, 622, 523, and the amount of nickel content determines the energy density of the battery pack according to the content of nickel cobalt manganese. The higher the amount of nickel, the greater the energy density of the power battery pack. However, the higher the content of nickel, the worse the thermal stability of the battery, that is, it easily out of control. This is why the battery spontaneous combustion accident in recent years has frequently issued, and the cause of the 811 power battery. The market has gradually begun to avoid high-niome 811 three-dimensional lithium batteries, and even began to reverse, using low-nickel 523 three-dimensional lithium batteries many years ago. However, comparison of ternary and lithium iron phosphate materials, if the three yuan cannot use the high-nickel solution to occupy an advantage over the energy density, why should the three yuan lithium battery?