As soon as this news came out, it not only caused a sensation in the automobile industry and consumer groups, but also the capital market responded immediately, and BYD's stock once had a daily limit. With the exposure of data such as "having more than 300 patents", "increasing energy density by 50%" and "reducing cost by 30%", the face of the legendary "super lithium iron phosphate battery" gradually became clear. Then, as the "secret weapon" that BYD has been developing for many years, where is the "blade battery"?
Why is it called "blade battery"?
In fact, "blade battery" is a name of a new generation of lithium iron phosphate battery recently promoted by BYD. In fact, it is the "super lithium iron phosphate battery" developed by BYD for many years. Perhaps manufacturers hope to get more volume through a sharp and relatively figurative name.
The so-called "blade battery" is actually developed for BYD, and its length is greater than 0.6? M's large batteries are arranged in an array and inserted into the battery pack like "blades". On the one hand, it can improve the space utilization rate of power battery pack and increase energy density; On the other hand, it can ensure that the battery cell has a large enough heat dissipation area and can conduct the internal heat to the outside to match the higher energy density.
Compared with BYD's previous lithium iron phosphate battery, the upgrade of "blade battery" focuses on the fact that the battery can be directly integrated into a battery pack (CTP technology) without modules, which greatly improves the integration efficiency.
But in fact, BYD is not the first manufacturer to use CPT technology. As the world's largest power battery manufacturer, Contemporary Ampere Technology Co., Ltd. used CPT technology before BYD. 2065438+In September 2009, Contemporary Ampere Technology Co., Ltd. demonstrated this technology at the Frankfurt Motor Show.
On a global scale, Tesla, Contemporary Ampere Technology Co., Ltd., BYD, Honeycomb Energy, etc. have successively started research and development and announced that they will mass-produce CTP-related products, and the modular-free power battery pack is becoming the mainstream technical route.
▲ Traditional ternary lithium battery pack
The so-called module is a module composed of some related parts, which can also be understood as the concept of assembly of a component. In the field of battery pack, several batteries, conductive strips, sampling units and some necessary structural support components are integrated to form a module, also known as a module.
▲ CTP battery pack of Contemporary Ampere Technology Co., Ltd.
And CPT(cell? Where to? Pack) is to integrate the battery directly into the battery pack. Because the assembly of battery module is omitted, the number of battery parts is reduced by 40%, the volume utilization rate of CTP battery pack is increased by 15%-20%, the production efficiency is increased by 50%, and the manufacturing cost of power battery is greatly reduced.
What are the advantages compared with other power batteries?
As far as anode and cathode materials are concerned, lithium ternary and lithium ferrous phosphate are the most widely used automotive power batteries at present, but these two types of power batteries have their own advantages. Compared with ternary lithium batteries, lithium iron phosphate batteries have higher safety, longer cycle life and lower cost, but there is less room for improving energy density.
But if we can solve the short board of low energy density of lithium iron phosphate battery, won't all problems be solved? This is true in theory, but it is quite difficult. Therefore, developing CTP technology can maximize the specific energy density of the battery without changing the anode and cathode materials.
It is reported that the specific energy density of BYD's "blade battery" can reach 180Wh/kg, which is about 9% higher than before. This data is not weaker than "8 1 1" ternary lithium battery, which means that "blade battery" has reached the high level of ternary lithium battery while retaining the high safety, high stability and low cost of lithium iron phosphate battery.
What is overlooked by many people is that the energy density of the battery can actually be defined from two dimensions. First, the energy density per unit weight, that is, the dimension adopted by the Ministry of Industry and Information Technology, is directly related to how much subsidy can be obtained, and also affects the endurance of vehicles to a certain extent. The other is the energy density per unit volume, which is not in the evaluation standard of the Ministry of Industry and Information Technology, but it will also affect the endurance of the vehicle.
BYD's "blade battery" has increased its weight specific energy density by 9% compared with the previous generation battery, but its volume specific energy density has increased by as much as 50%, which is the real superiority of "blade battery". Because this means that BYD can increase the vehicle battery capacity by 50% for the same model in the future. Although it may also bring the influence of weight increase, the actual endurance performance will definitely be greatly improved. For example, the first Korean EV equipped with a "blade battery" has a endurance of about 600km, although it is a medium and large car with a length of nearly 5 m..
For consumers, battery life is actually secondary, and battery safety is the top priority. In recent years, electric vehicle safety accidents have occurred frequently, most of which are caused by battery fire. In order to improve the cruising range, most car companies now use ternary lithium batteries with a high proportion of nickel. The "622" model is very common now, and even "8 1 1" has been installed in mass production models, which means that only 20% of the batteries are cobalt and manganese. While the cruising range has improved, battery safety has become a major hidden danger. In contrast, lithium iron phosphate batteries are more reliable in this respect.
However, even if the technical bottleneck of low energy density is broken, the lithium iron phosphate battery is not perfect. For example, in terms of low temperature resistance, the lower limit of ternary lithium battery is MINUS 30 degrees, and the lower limit of lithium iron phosphate battery is only MINUS 20 degrees. Then in the cold northern region, the performance decline of lithium iron phosphate battery will be more obvious in winter. But Beijing is also the main consumption area of pure electric vehicles in China. Even if BYD is not worried about selling in the south, its power battery will be supplied to the outside world in the future. If we lose the northern market, we will easily fall into a passive position in the competition with rivals such as Contemporary Ampere Technology Co., Ltd..
Which cars will be equipped with "blade batteries"?
As early as 20 19, it was widely rumored that Han would be BYD's first model equipped with "blade battery" (then called super lithium iron phosphate battery). Recently, BYD Korea's application information also appeared in the latest product announcement of the Ministry of Industry and Information Technology.
▲ Korean EV declaration information
▲ Korean DM declaration information
According to the application information, BYD Han EV will be equipped with lithium ferrous phosphate "blade battery", which is produced by Chongqing Fudi Lithium Battery Co., Ltd., which is highly consistent with the information previously announced by Wang Chuanfu. The Korean DM is equipped with a nickel-cobalt-manganese lithium battery, which is commonly referred to as a ternary lithium battery. It is made by Shenzhen BYD Lithium Battery Co., Ltd. ..
At present, there is no mass production plan of "blade battery" on other models, and Korean EV is the only model that can be determined at present. Because the flat and slender shape of the "blade battery" itself determines that the vehicle must have a wide layout space, at present, the "blade battery" is only suitable for being carried in a car with a large body size like Korea, and the wheelbase of the Korean EV has reached 2920 mm 。
In addition, in fact, CTP battery pack technology has been introduced in the field of commercial vehicles for a long time, such as passenger cars. Because of the large arrangement space of bus batteries, its compatibility with CTP battery pack is higher than that of traditional power batteries. Therefore, BYD will invest a lot of "blade batteries" in commercial vehicles in the future, such as pure electric buses.
In terms of foreign cooperation, BYD established a joint venture with Toyota last year, and cooperation with Audi (battery procurement) is also under negotiation. Among the two partners, Audi may prefer to use BYD's "blade battery".
In fact, as early as last September, it was reported that Audi was negotiating with BYD to include the latter among its battery suppliers. It is reported that BYD's power battery will be used in high-end models based on the PPE platform jointly developed by Audi and Porsche.
Considering that the main task of PPE platform is to build high-end models, the "blade battery" with strong comprehensive performance but high requirements for layout space just plays a role. Compared with the ternary lithium battery of contemporary Amperex Technology Co., Ltd. or other manufacturers, BYD's "blade battery" is more reliable, which is also valued by Audi.
There is no doubt that the mass production of "blade battery" represents BYD's technological progress and may become a landmark work in the history of brand development. At present, the performance and market potential of "blade battery" are worth looking forward to. But judging whether a product or a new technology is successful still needs to be tested by the market. For BYD, is "Blade Battery" a milestone or a "sad mileage"? We'll have the answer soon.
This article comes from car home, the author of the car manufacturer, and does not represent car home's position.