The emergence of "blade batteries" has sparked a new round of heated discussions in the new energy industry. At the 100-person meeting for electric vehicles, BYD Chairman and President Wang Chuanfu mentioned BYD's "blade battery" for the first time, which is a new battery technology based on lithium iron phosphate technology. It will be the first to be used in BYD's new medium and large new energy sedan Han superior. The addition of "blade battery" enables this new car to achieve a pure electric cruising range of up to 605KM.
Currently, the new energy vehicle battery packs on the market can be roughly divided into two categories. Passenger car battery packs are mostly ternary lithium batteries, while lithium iron phosphate batteries are more commonly used in commercial applications. on the car model.
According to statistics, the installed capacity of new energy vehicles in 2019 was approximately 1.175 million, of which the installed capacity of ternary lithium batteries was 37.5GWh, accounting for 60%, while the installed capacity of lithium iron phosphate batteries was 20GWh, accounting for 60%. The ratio is only 32. What are the factors that cause such a big gap between the two technical routes? This has to start with policy.
In the competition for battery technology routes, lithium iron phosphate batteries will win back the victory
As we all know, lithium iron phosphate batteries are BYD’s pioneering work, and my country’s new energy vehicles are in the early stages of development. , followed the route of national promotion, subsidies and commercialization, so BYD at that time took the leading advantage with its lithium iron phosphate technology route.
Until later, my country's new energy vehicle subsidy policy began to favor cruising range and energy density, so high energy density and high cruising range became the focus of obtaining high subsidies.
With the same volume and weight, ternary lithium batteries have the advantages of higher battery life, greater energy density, and more efficient charging efficiency. Coupled with the policy guidance, ternary lithium batteries have come from behind. . As a result, many car companies have abandoned lithium iron phosphate batteries and switched to ternary lithium batteries.
At present, most of the mainstream ternary lithium batteries are batteries with nickel cobalt manganese as the cathode material. In this kind of battery, the higher the nickel content, the greater the energy density of the battery, but the worse the stability of the corresponding power battery; the higher the manganese content, the higher the stability of the power battery, but the energy density The lower. According to the content ratio of nickel, cobalt and manganese, nickel-cobalt-manganese ternary lithium batteries are divided into 532, 622, 811 and other categories.
Limited by the characteristics of ternary lithium batteries, many car companies are pushing for higher energy density, which is also accompanied by many spontaneous combustion cases. Last year alone, there were more than 100 accidents involving new energy passenger vehicles spontaneously igniting in place in China, which also caused consumers to have greater concerns about the reliability of new energy vehicles.
On the contrary, lithium iron phosphate batteries have higher safety guarantees, but energy density has always been a bottleneck restricting their development, and the birth of "blade batteries" solves this problem.
Technological innovation brings a "second spring" to lithium iron phosphate batteries
The so-called "blade battery" is actually a lithium iron phosphate battery, but the new technology has changed it The cell layout allows it to store more energy in a smaller volume. According to BYD's patent application, the new "blade battery" uses a long battery cell design with a square aluminum shell. The battery cell is designed to be flat. The maximum length of the battery cell can reach 2.5 meters, which is a traditional More than ten times that of lithium iron phosphate batteries.
It is named "blade battery" because such long cells are arranged in an array and can be inserted into the battery pack like a "blade". This approach can greatly improve the space utilization of the battery pack and increase the energy density. According to information from the Ministry of Industry and Information Technology, the energy density-to-weight ratio of the "blade battery" installed on BYD Han EV is 140Wh/kg.
Secondly, it can ensure that each battery core has a large enough heat dissipation area to make the overall heat dissipation better. Furthermore, compared with previous lithium iron phosphate batteries, the cells of "blade batteries" can also be modularized and directly integrated into battery packs, thereby greatly improving integration efficiency. In addition, the "blade battery" has a longer service life than traditional ternary lithium batteries, and the number of battery cycles can be greatly increased, with a service life of up to one million kilometers.
On the other hand, because the "blade battery" has a higher runaway temperature than the ternary lithium battery, it is also safer and has stronger resistance to deformation, extrusion, and puncture. The probability of short circuit inside the battery pack is very small, and it is not easy to induce spontaneous combustion of new energy vehicles in situ.
With "Blade Battery" as the forerunner, battery manufacturers are breaking down technical barriers
In fact, there is no absolute winner between lithium iron phosphate battery and ternary lithium battery technology. , there is only relative applicability. By innovating and upgrading the shortcomings of lithium iron phosphate batteries, BYD has made its performance even better in all aspects. It has emerged as a market that has gradually lost its policy tilt, and once again competes with ternary lithium batteries.
As of January this year, the sales volume of the domestic new energy vehicle market has declined for six consecutive years. Coupled with Tesla’s “intrusion”, many independent brand new energy vehicle companies have been lamenting, and this is giving rise to BYD has a chance to break through.
The main reasons why many consumers are unwilling to buy new energy models are "immature technology", "worry about safety", "anxiety about battery life", etc., and these concerns have been greatly affected by the arrival of "blade batteries" There will be some changes. BYD has applied the "blade battery" to its new mid-to-large new energy sedan Han EV, using the power of its brand flagship to demonstrate its strength to rivals in the market.
With CATL’s “811 battery” with an energy density to weight ratio of 180Wh/kg, GAC Trumpchi Aion? LX has broken through the 650km pure electric range mark, so many people regard the “blade battery” Compare with "811 battery".
Indeed, the current energy density to weight ratio of 140Wh/kg of the "Blade Battery" is not as good as the 180Wh/kg level of CATL's 811 battery, but it is reported that BYD will plan the single energy density to weight ratio in the next two years. A new generation product with a capacity of over 180Wh/kg, not to mention CATL’s 811 battery has not officially been put into mass production at this stage.
From the launch of BYD’s “Blade Battery”, it is not difficult to find that the new energy automobile industry is quietly changing. Ternary lithium batteries have always been the mainstream choice of new energy vehicle companies, but when lithium iron phosphate batteries usher in technological innovation and enter the market again, the competitiveness of ternary lithium batteries will gradually weaken.
Not only BYD’s “blade battery”, Tesla has also recently discussed with CATL and plans to equip domestic models with cobalt-free batteries, that is, lithium iron phosphate batteries, and CATL is also actively developing energy density batteries. Higher CTP iron lithium battery.
It is foreseeable that lithium iron phosphate batteries with higher energy density will become a new choice for new energy vehicle companies. BYD is also working hard to cross the edge and become a pioneer in the new wave of new energy vehicle development.
This article comes from the author of Autohome Chejiahao and does not represent the views and positions of Autohome.