In this regard, the Ministry of Industry and Information Technology specially issued the "Notice on the Investigation of Safety Hidden Dangers of New Energy Vehicles", requiring all new energy vehicle manufacturers to carry out the investigation of safety hidden dangers of new energy vehicles produced by their own enterprises, and at the same time assume the first responsibility for the safety of new energy vehicles, which shows that the spontaneous combustion incident has a heavy negative impact on the whole industry.
At this juncture, BYD's lithium ferrous phosphate "blade battery", which claimed to rectify the safety problems in the early stage of the industry, finally revealed its true colors at the online press conference on March 29th, and announced for the first time that it had successfully passed the complete test of the "acupuncture test".
As we all know, a good power battery product needs a series of experiments such as vibration test, simulated collision, extrusion and seawater immersion. The most difficult thing to pass is undoubtedly the acupuncture experiment, because the thermal runaway caused by collision and extrusion is only a probability event. The acupuncture experiment directly simulates the internal short circuit of the battery, and pierces the battery plate with a steel needle to cause the battery short circuit, thus causing the thermal runaway of the battery and testing the safety performance of the battery. Moreover, the observation of 1 hour shows that it is qualified without fire or explosion, which shows that its detection means are harsh.
In the test released at the press conference, under the same conditions, the temperature of ternary lithium battery changed dramatically at the moment of acupuncture, and the surface temperature quickly exceeded 500℃, resulting in extreme thermal runaway-violent combustion, and the eggs on the battery surface were blown up; After the traditional lithium iron phosphate battery was punctured, there was no open flame and smoke, the surface temperature reached 200℃-400℃, and the eggs on the battery surface were burnt at high temperature. BYD's "Blade Battery" has no open flame and smoke after penetration, and the surface temperature of the battery is only about 30-60℃. The eggs on the surface of the battery have not changed and are still in a flowable liquid state.
This result is enough to prove that the "blade battery" has completely got rid of the critical situation of thermal runaway that may occur in traditional power batteries. It also means that when the car is invaded by foreign objects and the battery is injured, it will not explode, which can effectively protect the safety of people inside the car.
With these security guarantees, Wang Chuanfu even said with confidence: "Blade battery embodies BYD's determination to completely end the safety pain point of new energy vehicles, and is more capable of leading the global power battery technology route back to the right path and completely erasing the word spontaneous combustion from the dictionary of new energy vehicles."
In fact, safety has always been the long-term advantage of lithium ferrous phosphate route power battery, but in fact, the greater significance of "blade battery" is to improve the cruising range.
Lithium iron phosphate battery itself has the advantage of high safety, but because of its relatively low energy density, it is left behind by ternary lithium battery with higher energy density but poor natural thermal stability in the blind pursuit of cruising range by new energy passenger car manufacturers.
However, ternary lithium battery is still expensive because of its certain cobalt content, and there are also hidden dangers of accidents, so advanced battery thermal management system must be used as an important supplement to instability. In contrast, the traditional lithium iron phosphate battery has the advantages of lower cost and better safety, but the problem lies in the lack of energy density, and the meaning of "blade battery" just makes up for this shortcoming.
According to BYD's patent scheme, "blade battery" is actually an innovative design of battery structure. Because the battery cell looks like a blade, it is named "blade battery".
It is precisely because of its flat structure that it is easy to stack, which reduces the use of beams or longitudinal beams in the battery pack, and even cancels the use of beams or longitudinal beams, thus improving the space utilization rate of the battery pack and further improving the capacity, voltage and endurance of the whole battery pack. Generally speaking, the comprehensive endurance effect of ternary lithium batteries can also be achieved by stacking the advantages of capacity and arranging lithium iron phosphate batteries with relatively low energy density.
So, what is the specific effect? BYD once cited an example in its patent. In electric vehicles, this design can change the original space utilization rate? About 40%, at most? More than 60%? 80%, which means the original? 400? A car with a cruising range of kilometers can be directly increased with a blade battery? 200? Kilometers battery life. At the same time, because fewer beams and longitudinal beams are used, the manufacturing process of the battery pack is simplified and the weight of the battery pack can be reduced to some extent. In theory, lightweight endurance can also be improved. In this way, this blade battery technology is really exciting.
In practical application, it is reported that BYD's latest blade battery will be installed on Korean EV for the first time and will be listed in June this year. The energy density of the battery system is 140Wh/kg, and there are two battery life versions, the single-motor version of NEDC has a battery life of 605km and the dual-motor version of NEDC has a battery life of 550km. This endurance level is quite competitive even compared with the super Tesla who plays ternary lithium batteries.
In addition, the cost of lithium iron phosphate battery itself is lower. According to relevant data, the current power consumption cost of LiFePO4 system can reach 600 yuan, while the common ternary 8 1 1 system on the market will cost 1000 yuan even if Tesla estimates it. Take a car with a 60-degree battery as an example. If lithium ferrous phosphate is used, the cost is 36 thousand yuan, and if ternary lithium battery is used, the cost is between 60 thousand yuan and 72 thousand yuan. The almost doubled cost difference is undoubtedly a world of difference for automobile manufacturers. From this point of view, BYD's "blade battery" can even solve the pain point of high cost of new energy vehicles to a certain extent, and it also makes people have more expectations for the final listing price of BYD Korea.
In the end, BYD, who showed off the blade battery, was obviously full of ambition. The emergence of blade batteries may change the industry's dependence on ternary batteries, return the technical route of power batteries to lithium ferrous phosphate, and even redefine the safety standards of new energy vehicles. More importantly, at present, the international mainstream power battery technology routes such as fuel cells, lithium iron phosphate batteries and ternary lithium batteries have experienced ups and downs. Only China has a complete and advanced lithium iron phosphate battery supply chain. If lithium ferrous phosphate returns to the track, BYD may become the hero of China's new energy "overtaking in corners".
* Some pictures are from the Internet. If there is any infringement, please contact to delete it.
Original article, reprint requires authorization.
-That? End-
This article comes from car home, the author of the car manufacturer, and does not represent car home's position.