Today, the subdivision direction of track stocks continues to be active. By the close, high-voltage fast charging rose 3.21%, Wanxiang Technology (301180.SZ) rose more than 12%, and 002900.SZ, 002806.SH and 002364.SZ rose by the daily limit.

Thanks to the advantages of high-voltage fast charging technology in charging efficiency and driving performance, since Geely first released the vast SEA architecture supporting 800V in 2020, domestic car companies have accelerated the layout of 800V high-voltage platforms.

As 800V models such as Polar Fox Alpha S, Avita 11, XPeng Inc. G9 and Great Wall Jiaolong have been on the market this year, 2022 will become the first year of mass production of 800V models. For a time, high-voltage fast charging has become a "hot word" in the new energy car circle.

Fast charging is fast charging, and the unit of measurement can be expressed as the charging rate (C). The higher the charging rate, the shorter the charging time.

From the point of view of the realization path, shortening the charging time is high current scheme and high voltage scheme respectively. Among them, high-current fast charging has some disadvantages, such as serious energy loss, low conversion efficiency and heavy burden of thermal management system. High-voltage fast charging has the advantages of high energy conversion efficiency and low heat, which can effectively alleviate users' life anxiety, which is the mainstream trend in the future.

From the perspective of industrial trends, first, high-voltage fast charging drives the power and complexity of the thermal management system to increase.

In terms of thermal management, the overall refrigeration / heating power under the 800V architecture increases, which leads to the increase of the use area of the water-cooled plate, the continuous optimization of its structure with the cell; the increase of refrigerant flow velocity / flow rate, the expansion of the flow control range of electronic expansion valve and the need to ensure high accuracy, large diameter and high precision electronic expansion valve is expected to become an industry trend, valve diameter design and system design with sensors and controllers are difficulties.

Second, the upgrade of high-voltage fast charge drive power devices is reflected in the trend of SiC replacing IGBT.

Instead of Si-based power devices, SiC-based power devices are mainly used in electronically controlled inverters, DC/DC converters, OBC and charging piles, which can increase the working frequency, reduce the loss, reduce the volume, increase the power density of components, and withstand high temperature and high pressure. Emphasis is placed on replacing SiIGBT with SiCMOSFET in electronically controlled inverters.

Third, high-voltage fast charging requires vehicle safety requirements to be upgraded to drive the corresponding parts upgrade.

The high-voltage connector ensures the safety of the high-voltage circuit connection, and the liquid-cooled fast filling pile will become the technical difficulty of the high-voltage connector in the future; the digital isolation chip, combined with different components, is used in different high-power electronic equipment for electrical isolation, and there is a trend of integration; because of its comprehensive advantages in high voltage resistance, energy storage effect and service life, thin film capacitor has become a new trend to replace electrolytic capacitor. High voltage DC relay with intelligent fuse provides safety redundancy for the whole vehicle.

With reference to the development process of mobile phone energy replenishment, fast charging is expected to become the best solution for the next generation of energy replenishment, and really solve the core pain point of electric vehicle battery life anxiety. The 800V fast phase filling large current scheme has relatively obvious advantages in cost, efficiency and technical difficulty, and the accelerated layout of various automobile companies is expected to enter the rapid release period.

According to Huachuang Securities estimates, the market size of 800V high-voltage fast charging industry is expected to reach 32.4 billion yuan in 2025 and 87.8 billion yuan in 2030. From 2021 to 2023, the domestic 800V high voltage fast charging industry has grown from scratch, and the compound growth rate is expected to exceed 70% (explosive growth) from 2023 to 2025, and about 20% from 2025 to 2030 (steady growth).

Societe Generale Securities suggests to focus on 800V fast charging related industry chain investment opportunities: 1) matching battery liquid-cooled water-cooled plate heat exchanger products: silver wheel shares

2) benefit from the trend of large-caliber electronic expansion valves: Shield environment

3) benefiting from electronic ceramic packaging, SiCMOSFET has made a breakthrough: China Ceramic Electronics

4) SiC all-in-one power electronic components have been mass produced, including DC/DC converter, charging boost module, OBC, etc.

5) SiC power solution, high-power OBC products have been mass-produced: Xinrui Technology

6) the performance of high voltage connectors is leading, and it is expected to benefit from the domestic alternative: Rekoda

7) benefiting from the first-mover advantage of liquid-cooled overcharge technology, charging gun products have become leading products: Yonggui Electric Appliances.