r03 battery materials are aimed at high-end

In the production of battery materials, my country has advantages in both upstream mineral resources and various battery materials, and some products are already in the world's leading position. Compared with Japan, South Korea and other countries, my country's low-end r03 battery products have more advantages, but there is still a big gap in some high-end products, especially in core materials and manufacturing processes related to battery safety.

Upstream raw material resources are scarce

Battery-grade lithium hydroxide monohydrate and battery-grade lithium carbonate can be used as lithium sources for the production of r03 battery positive electrode materials and electrolyte salt lithium hexafluorophosphate. Cobalt tetroxide is used to produce positive electrode materials, and battery-grade lithium fluoride is mainly used to produce battery-grade lithium hexafluorophosphate. Lithium hexafluorophosphate is the main raw material for the production of electrolyte, which accounts for about 50% of the cost of electrolyte. At present, only my country and Japan have achieved the industrialization of lithium hexafluorophosphate worldwide. Due to the high difficulty of production technology, it is mainly monopolized by several Japanese companies such as Kanto Electrochemical Industry, SUTERAKEMIFA, and Morita Chemical in the world, and only a few companies such as Do-Fluoride can produce it in China.

Zhang Yongwei, Secretary General and Chief Expert of the China Electric Vehicle Hundred People's Association, stressed that we should attach great importance to upstream resource issues. At present, lithium and cobalt materials account for a high proportion of batteries. my country's lithium resources are relatively abundant, but cobalt resources are poor. my country only accounts for about 1% of the global cobalt reserves. With the growth of electric vehicle production and sales, the bottleneck of upstream resources will become more and more prominent, and it is necessary to plan and layout as soon as possible. In addition, the technical bottleneck of upstream resource development in my country has also led to a low self-production rate of resources, which is also an important factor affecting the price of upstream materials.

Electrode materials continue to emerge

At present, the mainstream international battery types are basically lithium iron phosphate and ternary lithium batteries, of which my country's installed capacity of these two batteries reached 93.3% in 2017. At present, there is still room for the energy density of these two batteries to increase and the cost to decrease, and there is still a period of development in the industry.

However, the energy density has approached its physical limit, which is a bottleneck in the development of lithium batteries. New materials or technologies are needed to achieve a breakthrough in the energy density of lithium batteries. One way to improve energy density is to develop new positive electrode materials with higher charging and discharging platforms, such as lithium-rich manganese-based, nickel-cobalt-acid lithium, etc. Among them, the theoretical energy density of lithium-rich manganese-based materials can reach 900Wh/kg, becoming a hot spot for research and development. However, this material will generate oxygen during the cycle process, which will cause safety hazards, and the cycle life and rate performance are also low, so further research and development is still needed.

Another method is to increase the charging cut-off voltage of traditional positive electrode materials. After the voltage of the positive electrode material is increased, a high-voltage electrolyte is required to match it. Additives can play a key role in the high-voltage performance of the electrolyte, and have become the focus of research and development in recent years.

In terms of negative-electrode materials, lithium titanate has a high enthusiasm for research and development. This is because lithium titanate has a long cycle life of more than 10,000 times, and can be charged quickly, which is more suitable for energy storage fields that do not require space. Companies are also developing negative electrode materials such as silicon-carbon composite materials, graphene, and carbon nanotubes.

The diaphragm technology has the highest gold content

The diaphragm is the high-value-added material with the highest technical content in r03 battery materials. The performance of the diaphragm directly affects the capacity, life and safety performance of the battery. Only a few companies in China can mass-produce it, and it can only be used in the mid- and low-end markets. Foreign companies such as Japan's Asahi Kasei and South Korea's SK Corporation have basically monopolized the global market.

"The main material of the diaphragm is a porous polymer film (polyethylene or polypropylene). The diaphragm used in lithium batteries has strict requirements on safety, permeability, porosity and thickness. The technical difficulty lies in the engineering technology of pore making, the matrix material and manufacturing equipment. At present, the price of the diaphragm accounts for more than 10% of the total cost of the battery." Zhou Zhen, director of the Institute of New Energy Materials Chemistry of Nankai University, introduced. At present, the world's best r03 battery diaphragm materials come from two Japanese companies, Asahi Kasei and Tonen Chemical, and 90% of the domestic r03 battery aluminum plastic film market is also monopolized by Japanese manufacturers such as Showa Denko.

The Battery Industry Association estimates that my country's annual demand for high-quality automotive power battery diaphragm materials will reach hundreds of millions of square meters in the future. However, high-end diaphragm technology has a very high threshold. Not only does it require huge investments, but it also requires a strong R&D and production team, skilled process technology and high-level production lines.

Zhou Zhen believes that if domestic diaphragm companies want to achieve greater success, they must make efforts in three major areas, namely, surface treatment technology of basic materials, adhesive formulation technology, and product stamping and stretching, which involve materials, equipment, and process control. In addition, in the upstream of the diaphragm industry chain, core production equipment including domestic coating machines also needs to catch up and make greater breakthroughs as soon as possible.

Read recommendations:

501825 180MAH 3.7V

Lithium battery charging knowledge.48v 100ah lithium battery pack

What are the development prospects and trends of lithium batteries

521133 battery wholesaler

18650 2200mah battery