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Compared with prismatic batteries and cylindrical batteries, the biggest difference between pouch batteries is that the outer layer of the battery is only packaged with a layer of aluminum-plastic film, and there is no shell and other accessories for the outer layer of the prismatic battery. Not only have advantages in energy density, but also lower cost.
1. Competition in power batteries is intensifying
Data show that from January to November this year, the production and sales of new energy vehicles were 6.253 million and 6.067 million respectively, doubling year-on-year growth. In November, the market share of new energy vehicles has exceeded 30%, and the market prospect is broad. Power batteries are expected to achieve rapid development simultaneously, which also means that the degree of competition in this field will intensify.
In recent years, many power battery companies in the world have begun to try to achieve balance by changing the battery structure. But in essence, most of these power batteries still belong to the category of square batteries. In addition to prismatic batteries, some power battery manufacturers are also exploring in the field of cylindrical batteries and pouch batteries, hoping to meet the needs of future new energy vehicles with different battery forms.
2. Advantages of pouch battery
At present, due to reasons such as high cost and long R&D cycle, the power battery market is still dominated by square batteries and cylindrical batteries. Among them, prismatic batteries have the highest market share. In 2021, the market share of prismatic batteries will exceed 54%, and it is expected to rise further to 61.9% in 2022. However, from the perspective of the rising trend of installed capacity, the growth rate of pouch batteries is very rapid. Data show that in the first half of this year, the installed capacity of pouch power batteries was about 6.03GWh, a year-on-year growth rate as high as 72%.
On the car company side, pouch batteries have also begun to be favored by more and more car companies. The reason is that the pouch battery has its unique features. Not only have advantages in energy density, but also lower cost. Although the structure is simple, the aluminum-plastic film package can better ensure the safety of the power battery. The shell of the pouch battery is packaged in the form of aluminum-plastic film. Even if the battery is thermally out of control, the pouch battery will reduce the internal pressure by deflation to prevent the battery from spontaneous combustion and explosion.
On the other hand, pouch batteries have higher design flexibility. At the cell level, the thickness and shape of the pouch battery can be customized according to the customer's design requirements for their own products. At the level of modules and battery packs, pouch batteries can also be arranged in different shapes such as rectangles or T-shaped according to the needs of different models, so as to meet the space requirements of more models for power batteries. In addition, the vast majority of pouch batteries adopt the laminated process.
Compared with wound batteries, the number of tabs of laminated batteries can be nearly doubled, and the internal resistance is significantly lower than that of square batteries and cylindrical batteries. Therefore, the heat generated is also small, the self-consumption of the battery is significantly reduced, and the cycle life of the battery will be stronger. Most importantly, pouch batteries have higher energy density than prismatic and cylindrical batteries. According to the data, the ternary pouch single cell is 10%-15% higher than the ternary square on average. The current mass-produced ternary square power batteries in the industry have an average cell energy density of 210-230Wh/kg.
The energy density of the ternary pouch power battery with the same material system reaches 240-250Wh/kg, which can better meet the needs of future power batteries for lightweight and long battery life. As the battery with the highest energy density in the liquid battery field, the pouch battery is currently the closest to the high energy density level of solid-state batteries. The solid-state battery is almost regarded by the entire industry as the next-generation mainstream technology development direction following the liquid battery.
However, due to issues such as material costs and supply chain reshaping, solid-state batteries have not yet embarked on the road to mass production. According to analysts in the industry, all-solid-state batteries are expected to achieve significant cost reduction and mass production in the next 5-10 years. During the transition period of this technology route, pouch batteries with higher energy density are expected to stand out.
3. Pouch batteries explosion eve
At present, the new energy vehicle market is developing at a high speed, and the shipment of power batteries has also increased significantly. At the 2022 World Power Battery Conference, experts predicted that China's power battery shipments will exceed 1TWh in 2025, and the output value will exceed 1 trillion RMB. As the next stage of development of power batteries, the pouch battery market is about to enter the eve of explosion. In fact, in the world, the pouch battery route that meets the car battery voltage has become the mainstream choice of overseas car companies.
At the same time, a new process has emerged in the field of pouch batteries in recent years, which has further solved the original problems of complex production process and high cost. In September this year, Farasis launched a new power battery solution, the new SPS (Super Pouch Solution). SPS has many characteristics such as high performance, low cost, and high adaptability, which solves the shortage of pouch batteries to a certain extent. At present, the module-free technology has been applied in the field of square batteries and cylindrical batteries. This technology reduces or eliminates the three-level pack structure of the battery "cell-module-whole module-free technology in a square package".
It can not only effectively increase the energy density of the power battery, but also reduce the number of components of the battery pack, and is more conducive to improving the integration and adaptation flexibility of the entire system. In order to alleviate the current consumers' anxiety about charging new energy vehicles, a small number of car companies directly choose battery swap and provide services to consumers in a simpler and more direct form. In contrast, more car companies are working hard to improve the mileage of new energy vehicles and increase the charging speed, which is also the direction for power battery manufacturers to develop new technologies.
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