Diaphragm is one of the key raw materials of lithium battery. Diaphragm is the key inner component with the most technical barriers in the lithium-ion battery industry chain. The cost of diaphragm in battery accounts for about 10%. The cost of diaphragm includes raw material cost, energy cost, labor cost, depreciation and amortization, etc. Among them, the cost of raw materials accounts for the largest proportion, about 41%; Energy costs mainly include water and electricity costs, accounting for 18%; The high cost of diaphragm equipment leads to a high proportion of depreciation and amortization, up to 23%. Diaphragm is the best track among the four materials. Under high barriers, the industry has high concentration and strong profitability. Due to the high industry barriers, the concentration of diaphragm industry is higher than that of other lithium battery materials. In 2020, CR3 and Cr6 will reach 62% and 80%, higher than that of other lithium battery materials. In terms of profitability, the gross profit margin of diaphragm is also higher than that of positive electrode, negative electrode and electrolyte.
Lithium diaphragm industry has high industry barriers. Lithium battery separator is a technology intensive industry, which needs long-term technology accumulation. The diaphragm project needs to invest a lot of money. The investment of 100 million flat diaphragm project is about 360 million yuan, and the equipment investment accounts for more than 50%. At present, diaphragm equipment is jointly designed and customized by diaphragm manufacturers and equipment manufacturers according to production conditions. Head diaphragm enterprises have been bound with major diaphragm equipment manufacturers. At present, there is a bottleneck in the supply of diaphragm production equipment, which is a relatively large restrictive factor in the expansion of diaphragm production, resulting in the expansion cycle of about 2-3 years. The diaphragm industry has high customer barriers and long certification time. Generally, the overall certification period takes about 1-2 years, and it is not easy to change suppliers after certification, so the cooperation relationship is stable.
Diaphragm wet process occupies the mainstream technical route. According to the microporous pore forming mechanism, the manufacturing of diaphragm base membrane is mainly divided into dry method and wet method. The core advantage of dry process diaphragm lies in its lower cost, but the horizontal strength produced by dry process is poor, the pore size and distribution are uneven, and the stability is poor; Wet diaphragm can improve the energy density of lithium battery, which is generally used to manufacture high-end thin films. However, the wet process has high cost and large investment. The market share of wet diaphragm continues to increase. In 2021, the power market continues to exceed expectations. With the continuous release of new capacity of wet diaphragm, wet diaphragm firmly occupies the leading position in the market, accounting for 74%.
Diaphragm market concentration will continue to improve. Global diaphragm production capacity continues to concentrate in China, and the Chinese market continues to move closer to leading enterprises. The global diaphragm competition pattern is dominated by four countries. China, South Korea, Japan and the United States have market shares of 43%, 28%, 21% and 6% respectively. According to the statistics of Gaogong lithium battery, the market share of China's top 6 lithium battery diaphragm enterprises in 2021 was 80.8%, which is higher than that in 2020. In terms of wet diaphragm, wet diaphragm presents an industry pattern of "one super and many strong", and Yunnan Energy New Material Co.Ltd(002812) has a market share of more than 50% in wet diaphragm. In terms of dry process diaphragm, the market pattern of "three pillars" appears as a whole. The market share of ZTE new materials, Shenzhen Senior Technology Material Co.Ltd(300568) , Huiqiang new materials in the first tier has increased steadily, and the CR3 of dry process diaphragm market is close to 70% in 2021.
Diaphragm supply and demand are in tight balance, and the expansion of diaphragm enterprises is accelerated. The explosive growth of the global new energy vehicle and energy storage market has driven the demand for lithium diaphragm in the upstream. According to evtank data, in 2021, the overall global shipment of lithium-ion batteries was 562.4gwh, with a significant year-on-year increase of 91.0%; In 2021, China shipped 7.8 billion square meters of lithium battery diaphragms, with a year-on-year increase of more than 100%. In terms of demand, we estimate that the global lithium battery demand from 2022 to 2025 is expected to be 813.45, 120093, 180529 and 275734 GWH respectively, and the corresponding diaphragm demand is 11.592 billion square meters, 17.113 billion square meters, 25.725 billion square meters and 39.292 billion square meters respectively. The growth rate of diaphragm demand is 44.6%, 47.6%, 50.3% and 52.7% respectively. In terms of supply, leading enterprises have announced to expand production. According to incomplete statistics of Gaogong lithium battery, in 2021, China's diaphragm enterprises plan to expand production capacity (including coating capacity) by about 22 billion square meters, with a total investment of more than 56 billion yuan. The total existing and planned production capacity of top 10 diaphragm enterprises has exceeded 43.8 billion square meters.
Supply and demand reversed and diaphragm prices showed an upward trend. The supply-demand relationship of diaphragm in China has gradually changed into short supply. The supply and demand of mainstream lithium diaphragm enterprises are in tight balance. The head diaphragm enterprises are almost full of production and sales, and the capacity utilization rate of second tier enterprises has increased. Superimposed on the impact of the epidemic, the operating rate of the lithium battery diaphragm industry decreased, affecting the supply to a certain extent. In February 2022, the operating rate of the lithium battery diaphragm industry was 61.29%, down 10.99% month on month. Polyethylene PE, the raw material of diaphragm, accounts for a high proportion of raw materials. The spot price of high-density polyethylene has increased from US $846 / ton at the beginning of 2020 to US $1241 / ton at present, and the overall price has increased greatly. In 2021, the price of dry process diaphragm and wet process diaphragm will rise, with the rise of dry process diaphragm by 5 ~ 10% and wet process diaphragm by 10 ~ 15%. After 2022, the demand for lithium batteries increased rapidly, which led to a sharp rise in the demand for diaphragm. Superimposed on the outbreak of the national epidemic and the upgrading of epidemic prevention policies in various regions, the main producing areas of diaphragm were affected to a certain extent. The supply of diaphragm gradually failed to meet the downstream demand, and the tension between supply and demand in the diaphragm industry was further amplified. At the same time, affected by the sharp rise in international oil prices, the market price of diaphragm raw materials rises accordingly. At present, the diaphragm price remains stable as a whole, and there are still rising expectations in the future. The major diaphragm manufacturers benefited from the strong demand of the industry and the accelerated release of production capacity. With the expansion of diaphragm shipment scale, the unit cost of diaphragm enterprises decreased significantly, superimposed with the optimization of customer structure, and the trend of improving profitability was obvious.
Investment suggestion: diaphragm leading enterprises have the advantages of equipment, production capacity, technology, cost and customers. Under the background of tight balance in the industry, they will usher in the rise of both volume and price. HENGQIANG, the leading manufacturer of diaphragm, has outstanding scale and technical advantages, and the oligarchy pattern is becoming increasingly clear. At the same time, it has long-term cooperation with equipment end companies to lock in the capacity of equipment manufacturers in the next three years, with obvious advantages in capacity expansion; In terms of customers, the overall certification period of battery manufacturers for diaphragm manufacturers takes about 1-2 years, and it is not easy to change suppliers after certification. It is difficult for latecomers to enter the supply chain of battery manufacturers. It is suggested to focus on Yunnan Energy New Material Co.Ltd(002812) , Shenzhen Senior Technology Material Co.Ltd(300568) .
