From the perspective of the product composition of lithium batteries, its four key battery materials include cathode materials, anode materials, electrolytes and separators, and they all face certain development restrictions. Among battery materials, the price of lithium carbonate, the core raw battery materials of the cathode, has skyrocketed and lithium resources are in short supply. The specific capacity of the anode material graphite approaches the theoretical limit. The production capacity of important additives in the electrolyte is insufficient, and the price of organic solvents is rising. The supply of battery separators is tight, the technical barriers are high, and there is import dependence.
In this regard, relevant Chinese lithium battery companies have strengthened localization substitution and increased effective supply through technological innovation, capacity expansion, recycling and other means in response to different problems arising from different battery materials, so as to relieve the pressure on the supply chain of battery materials.
1. Cathode material - dismantling and recycling for reuse
Cathode materials account for 20%-30% of the production cost of lithium batteries, and are an important factor in determining the performance of lithium batteries. The main technical routes of battery materials in cathode include lithium cobalt oxide, lithium manganate, lithium iron phosphate, and ternary materials. With the change of technology, high nickel ternary with energy density advantages and lithium manganese iron phosphate with safety and economic advantages are the main development directions.
Ternary materials and lithium iron phosphate are the two most mainstream battery materials use的in cathode in the market, and both have their own advantages and disadvantages in terms of cost and performance. Lithium iron phosphate batteries have the advantages of good safety, easy availability of raw materials, low cost, and excellent cycle performance, but their energy density is low, generally maintained at around 160Wh/kg. The biggest advantage of the ternary lithium battery is its high energy density, which can reach 350Wh/kg, but the risk of thermal runaway is high, the cycle life is short, and the high cost of raw materials is also the shortcoming of the development of the ternary lithium battery.
At present, in terms of the overall industry situation of cathode materials for lithium batteries in China, battery materials for cathode are in the middle of the industry chain and are the key link in determining the cost and performance of lithium batteries. From the perspective of resource endowment, China's lithium resources are relatively scarce. The explosive growth of the new energy vehicle market has caused the industry to face the dilemma of insufficient supply and demand of lithium resources.
According to relevant data, on September 21 this year, the average price of battery-grade lithium carbonate, the core raw material of the positive electrode of lithium batteries, reached 510,000 RMB / ton, compared with 50,000 RMB / ton at the beginning of last year, the price increased by nearly 10 times. In order to alleviate the shortage of lithium resources and the skyrocketing growth of core raw materials, Chinese companies have used technical means such as dismantling and recycling to extract core raw materials such as nickel, cobalt, and lithium in power batteries for reuse.
2. Anode materials - technological breakthroughs realize raw material replacement
As the carrier of lithium ions and electrons, the battery materials for anode are mainly responsible for the storage and release of energy, which can directly affect the performance of the battery such as energy density, cycle life, safety, and fast charging capability. At present, artificial graphite is the main anode material, which accounts for about 10%-15% of the cost of lithium-ion batteries. However, from the perspective of application, the actual specific capacity of graphite anode materials has reached 360-365mAh/g, approaching the theoretical limit of 372mAh/g, which restricts the development of the industry.
The industry generally believes that silicon-carbon anode battery materials with high specific capacity (silicon specific capacity can reach 4200mAh/g, which is 10-12 times that of graphite battery materials) will become the development direction of anode materials in the future. Although the advantages are obvious, the expansion rate of silicon materials easily affects the first charge efficiency and life of the battery, which restricts its commercial application in the anode.
According to reports, the expansion rate of silicon is as high as 320%, which is about 32 times that of graphite battery materials. In this regard, Chinese lithium ion anode material companies actively follow up technology research and development, improve the electrochemical performance of silicon-based battery materials in anode to improve cycle life and first charge efficiency, and have achieved remarkable results.
3. Electrolyte - expanding raw material production capacity
As one of the important components of battery materials, electrolyte, known as the blood of lithium-ion batteries, undertakes the heavy task of transporting lithium ions. In general, the electrolyte is prepared from high-purity organic solvents, electrolytes, additives and other materials in a certain proportion under certain conditions, accounting for about 5%-10% of the production cost of lithium batteries.
As an important additive in lithium battery electrolyte, vinylene carbonate (VC) can improve battery capacity and cycle life, play a significant role in improving the overall performance of lithium batteries, and the market demand continues to increase. As an important part of organic solvents, the demand for carbonates is also rising rapidly. In this context, China's lithium battery electrolyte companies are actively expanding their production capacity to ease the pressure on supply and demand.
4. Separator - innovation and production expansion to achieve Chinese substitution
The separator is located between the cathode and anode inside the battery, which prevents electron transport while ensuring the passage of lithium ions. It is a thin film with a microporous structure. In battery materials, The battery separator is the key inner layer component with the most technical barriers in the lithium-ion battery industry chain, and the cost of the power battery accounts for about 10%-20%.
In recent years, with the vigorous development of the lithium battery market, lithium battery separators, as one of the important lithium battery materials, have continuously expanded in demand and tight supply. At the same time, limited by technology, capital and equipment, most of the domestic high-end lithium battery separators rely on imports. In order to change this situation, Chinese lithium battery separator companies have increased technological innovation and planned to expand production capacity to meet the continuous release of market demand.
After years of development and innovation, China's lithium battery industry has made great breakthroughs in both quantity and quality. Relevant data show that China's lithium battery shipments will reach 229GW in 2021, and it is expected that shipments will reach 610GW in 2025, with a compound annual growth rate of more than 25%. Looking forward to the future, with the technological breakthrough and production layout of Chinese companies in the field of lithium battery materials, the current situation of the industry may be effectively improved, and a sustainable development path of green economy will be formed. Finally, the high-quality development of the industry is realized.