CR2430 battery.Seven major lithium-ion battery technologies and resources subject to foreign restrictions

Against the background of the rapid development of the lithium battery industry, domestic companies are also facing many problems that they have not mastered core technologies.

With the outbreak of the Sino-US trade war, the United States has imposed punitive tariffs on some Chinese companies, which has affected the import and export of some Chinese high-tech companies. In this trade war, many Chinese companies have exposed the problem of missing core technologies and weak R&D capabilities, which has very significant constraints on the future development of my country's high-tech industry.

As a clean, efficient and economical energy storage product, lithium-ion batteries have been widely used in digital products such as mobile phones, tablets, and laptops in the past decade. In recent years, new energy vehicles have begun to be promoted on a large scale. Companies have focused on the R&D and production of power lithium batteries. The upstream and downstream lithium-ion battery industry chains have become more complete, and the output of power lithium batteries accounts for more than half of the world's production.

The core technology of lithium-ion batteries mainly involves raw materials, cells, equipment, battery packs and other aspects, and plays a decisive role in the performance and cost of batteries. Although my country's lithium-ion battery industry chain is relatively complete, it is still restricted by foreign technology or resources in terms of separators, pVDF, water-based binders, aluminum-plastic films, NCA, automation equipment, and cobalt mines.

1. Diaphragm material

The dry process is relatively mature, but there is still a gap between high-end wet process separators and foreign countries. The raw materials PE and production equipment of separators are heavily dependent on imports. As one of the key materials of lithium-ion batteries, the separator must not only prevent contact between the positive and negative electrodes, but also ensure that electrolyte ions can pass through. This concerns the thickness, porosity, air permeability resistance, internal resistance, puncture strength, mechanical strength, High requirements are put forward in terms of pore size and consistency. Domestic separators started late, and the technological maturity of domestic companies is not high. Although the localization rate has increased in recent years, especially in dry process separators, it has been greatly improved. However, in terms of wet process, it is limited by technology and technology and production equipment. At present, some domestic companies such as Jinhui Hi-Tech and Cangzhou Mingzhu use their own assembly equipment for wet process equipment. However, in order to ensure product consistency, pore uniformity, wettability and other properties, most domestic separator companies still use Master, Bruckner, Toshiba, JSW, KOBELCO and other Japanese and Korean equipment. In addition, the pE material as the main material has high requirements on purity and stability. The supply of pE materials to domestic separator companies is basically monopolized by several companies such as Japan's Mitsui and Korea Petroleum Chemicals. The purity of domestic polyethylene products does not meet the requirements. , is rarely used in high-end products, and is mostly used in some low-end products.

2. Separator coated with pVDF

At present, domestic power lithium battery separator coating pVDF mainly relies on imports. Only some companies use domestic pVDF, but the stability and material of domestic pVDF are poor. pVDF, also called polyvinylidene fluoride, has a melting point of 172°C, a heat deformation temperature of 112~145°C, and a long-term use temperature of -40~150°C. It is used in coated separators to enable the separator to be closely combined with the electrode. Due to the electrode With the support of the plate, the thermal shrinkage of the separator is enhanced, and it can also reduce free electrolyte and improve the safety of the battery. Foreign pVDF products are mainly reflected in their stability and high quality, including Akma and Solvay, which can be produced on a large scale, while domestic production scale is small and efficiency is low.

3. Water-based adhesive

The high-end water-based adhesive market is basically monopolized by Japanese companies such as Zeon, JSR, and Sojitz. Domestic companies only come from [ ]. Water-based binders are mainly used in positive and negative electrode binders and separator coatings, especially in high-nickel ternary products, which place higher requirements on binders. Japanese companies have been engaged in R&D and layout of water-based adhesives for more than ten years, and their technology and industrial supporting facilities in this area are very mature. The domestic adhesive industry started late, and supporting raw materials and production equipment rely on imports. There is a big gap between my country's raw materials and Japanese and Korean companies in terms of quality and purity.

4. Aluminum plastic film technology

Soft aluminum-plastic film relies heavily on imports. Only some companies can produce it, but its performance is not recognized by the industry. As a type of power lithium battery, soft-pack power lithium battery has the characteristics of high energy density, small internal resistance, and good cycle performance. It has great advantages in application in new energy vehicles, and its market share will continue to rise. As the outer packaging material of soft-pack batteries, aluminum-plastic film has very high requirements in terms of thickness, barrier properties, electrolyte resistance and stability. There is a big gap between the performance of domestic aluminum-plastic film products and foreign products, mainly reflected in the fact that it is difficult to reach the level of Japanese and Korean companies in terms of punching depth and precision control. At present, the domestic supply of aluminum-plastic films is basically monopolized by Japanese companies such as Showa Denko and DNp. Although some domestic manufacturers, including Zijiang Color Printing, Zhongjin Matai, Fosu Technology and other companies, have begun the research and development and manufacturing of aluminum-plastic films. , but in a short period of time, the performance of domestically produced aluminum-plastic films has not been recognized by domestic battery companies, and most of them are still imported. In terms of equipment, key equipment such as casting machines and extruders rely on imports, and are relatively restricted when expanding production.

5. NCA technology

The industrialization of NCA batteries in my country lags behind, and key NCA materials are mainly concentrated in the hands of Japanese companies. Entering 2018, ternary has become the area of greatest concern in the power lithium battery industry. Domestic ternary mainly adopts the NCM technology route, but there is basically no big breakthrough in NCA. NCA has the characteristics of high energy density, good rate characteristics, and good low-temperature performance. It is one of the most promising high-energy-density lithium battery cathode materials. Japanese and Korean companies have developed more from electric vehicles, batteries, NCA cathode materials, to precursors. Earlier, the technology was more mature and advanced, and a mutually supporting industrial chain and a relatively stable and mature supply chain had been formed between the upstream and downstream industries. At present, the NCA market is basically monopolized by Nippon Chemical, Sumitomo and Toda. In China, driven by the TESLA effect, some companies have begun the layout of NCA, but the output is relatively small. Except for the NCA precursor, other parts have certain gap.

6. Automation equipment

High-end automation equipment, especially cylindrical battery equipment, relies heavily on imports. As the output of lithium-ion battery companies continues to expand, the demand for lithium battery equipment continues to rise. However, due to the numerous processes and categories of lithium battery equipment, companies are over-concentrated and product homogeneity is serious. The stability, manufacturing process and digital control of domestic equipment are inconsistent with There is still a certain gap between foreign companies, especially in the field of cylindrical battery production, which mostly relies on imports. Domestic equipment cannot meet the requirements in terms of accuracy and automation.

7. Cobalt ore

my country's cobalt ore reserves are low and severely restricted by foreign countries. As an essential element in ternary materials, cobalt has a greater impact on the cost of ternary materials. At present, global cobalt mines are mainly distributed in places such as the Democratic Republic of the Congo, Australia, Cuba, Zambia and the Philippines. The reserves of these countries account for more than 80% of global cobalt reserves. However, the reserves of cobalt mines in my country are very low, with cobalt reserves of only 8 million tons, accounting for 1% of global cobalt reserves. The shortage of cobalt ore, coupled with the rapid rise in domestic demand for ternary materials, has pushed the price of cobalt from 200,000 yuan/ton to 500,000 yuan/ton, which has increased the cost of power lithium batteries and the company's risk.