In the early spring of 2026, the National Two Sessions have just come to an end, and the blueprint of the “Fifteenth Five-Year Plan” has become clearer in the heated discussions of the delegates. When the proportion of China’s non-fossil energy consumption exceeds 20%, and when policies actively promote the development of a green and low-carbon economy, the deep-seated challenges of energy system transformation have surfaced: how to develop and expand new energy and other emerging industries so that green power can not only be generated, but also be used well and steadily?
This is not only a topic for the power grid, but also for the lithium battery industry chain. In the “sandwich” structure of the lithium battery, the positive and negative materials must not be contacted, otherwise it will short-circuit and catch fire. The separator is the key material that separates the positive and negative electrodes at the physical level and only allows lithium ions to pass through. It does not contribute to the energy density, but determines the safety bottom line of the battery; it is as thin as a cicada, but it bears a critical responsibility. The industry calls it the “heart valve” of lithium batteries “.
While the world is seeking energy transformation, an intelligent factory is running quietly in Yuxi, Yunnan, in the hinterland of central Yunnan. A roll of silver-white film, in a highly clean production line smooth transmission, eventually become a thickness of only 5 microns of lithium battery diaphragm. It is thin to the 1/20 of A4 paper, but it can be pierced by hundreds of grams of heavy objects safely.
This is Enjie’s factory and a microcosm of China’s new energy materials from catching up to leading.
the critical responsibility between microns
2026 is the first year of the 15th five-year plan and the key sprint period for China to reach the carbon peak by 2030. At present, the national energy system is working around strategic tasks such as ensuring energy security, green and low-carbon transformation, and building an energy power. Li Chuangjun, Director of the New and Renewable Energy Department of the National Energy Administration, proposed to promote the expansion, quality and reliable substitution of renewable energy during the “Tenth Five-Year Plan. Behind this is a realistic test question. The proportion of “green” in the power system has increased rapidly. The safety and reliability of lithium batteries and other equipment have never been so important.
The role of the diaphragm in lithium batteries coincides with the depth of the four words “reliable replacement. It not only has to isolate the positive and negative electrodes to prevent short-circuit fires, but also directly affects the energy density and rate performance of the battery through its own thickness, porosity, puncture strength and other indicators. It can be said that without the technological breakthrough of the diaphragm, there would be no high energy density power battery today. It is an indispensable key material in the process of new energy industry from 0 to 1, and then from 1 to 100. At present, Chinese diaphragm manufacturers have occupied nearly 90% of the global market share. In this field, Enjie has become a global leader. According to SNE Research data, from January to October 2025, Enjet’s market share is firmly at the top of the world.
“The separator does not contribute to the energy density in the battery, but in order to make the battery pack more active materials in a limited space and increase the energy density, we need to keep the separator thin.” Jiao Lingkuan, vice president of Enjet Global Research Institute, explains the underlying logic of the industry. Being thin means challenging the limits of physics. The thickness of an ordinary A4 paper is about 100 microns, while the thickness of Enjie’s main product is only 1/20 of that. However, extreme thinness cannot be at the expense of safety. The core function of the diaphragm is to isolate the positive and negative electrodes and conduct lithium ions. Once ruptured, the battery will short-circuit and catch fire, with disastrous consequences.
Based on the core index of diaphragm acupuncture resistance strength, Enjie shares put forward the concept of “micron-critical”, in a thickness of a few microns, the diaphragm can still withstand hundreds of grams of weight puncture without damage. From 9 microns to 7 microns, and then to 5 microns of wet diaphragm, Enjet shares follow the logic is always a thin thickness, high strength and fast conductive balance. In August 2025, Enjie officially launched a new generation of 5 micron ultra-thin high-strength diaphragm. Compared with the conventional 7 micron product, the thickness of the product is reduced by 28.5, but the needle strength is increased by 16.7, and the needle strength of the product reaches 550gf.
In 2025, the lithium battery separator industry experienced a bottoming out. Enjie shares are expected to achieve a net profit of 0.109 billion yuan to 0.164 billion yuan for the whole year, turning losses into profits year on year. Enjie’s main product is lithium battery separator, including base film and coating film two categories, the business sector accounted for more than 80% of the company’s revenue for a long time. Behind the performance reversal is Enjie’s concept of “three highs and one long”: high technology, high quality, high efficiency and adherence to long-termism. In the face of the price war in the industry, Enjet’s management clearly abandoned the short-term thinking of “price for quantity” and implemented the strategy of “differentiated competition + value upgrade.
“The reshuffle of the industry is inevitable. We are not afraid of price wars, but we refuse low-level repetition. The country said that the 15th Five-Year Plan should ‘expand the quantity, improve the quality and replace reliably. ‘We heard it in our ears and felt deeply.” Li Xiaoming, founder and chairman of Enjie, said, “In the past 20 years, our mission has been to ‘break the monopoly from scratch. ‘Today, Enjie’s mission has become ‘to be strong and lead the transformation’. Others are in roll thickness, we are in roll strength, roll safety, roll consistency, and make the same product more reliable. This is our moat.”
big country membrane force from catching up to leading
among the four main materials of lithium battery, diaphragm is the latest to realize localization and the highest technical threshold. What makes it one of the four main materials? How high is the technical threshold of wet diaphragm? In Enjet’s view, the technical threshold of wet diaphragm focuses on the four dimensions of material formulation, process accuracy, equipment capability and consistency control, superimposed on high capital investment and long R & D cycle, new entrants need to cross the whole chain barriers of materials, equipment and process, and continue to meet the challenges of battery technology iteration.
First, the base film manufacturing process. From polymer material formulation to two-way stretching process control, from extraction technology to heat setting process, every link needs precise control. The second is the design of microporous structure, the pore size needs to be controlled at the nanometer level (usually 0.01-0.1 microns), and the porosity needs to be between 30% and 50%. Too high will reduce the strength, and too low will affect the ionic conductivity. Once again, coating technology, ceramic, PVDF and other coating material dispersion, coating process accuracy, directly affect the functional performance of the diaphragm. The fourth is the integration of equipment and production lines. Extruders, drawing machines, extraction tanks and other equipment need to be customized. Imported equipment such as Japan Steel Institute and Germany Bruckner are expensive and complicated to maintain. Finally, consistency control, high-end diaphragm thickness tolerance should be less than or equal to 1 micron (such as 7 micron diaphragm actual thickness should be in the range of 6~8 microns), while continuous production of raw material fluctuations, temperature drift and other factors easily lead to performance differences, the need for full online monitoring.
Each of the above levels is enough to stop the vast majority of new entrants, and Enjet has already crossed one by one. Looking back, Enjie’s growth history is also a breakout history of China’s manufacturing industry.
“To be honest, now and then, in the dead of night, I still think of the days when I first started to do the diaphragm.” Li Xiaoming lamented, “The diaphragm this thing, looks like a layer of plastic film, but it involves polymer materials, nano-channel molding, precision coating, is an extremely complex science. When we first started debugging the equipment, many of our team ate and lived in the workshop for months.”
To make a world-class diaphragm, it is this belief that supports the Enjie team to maintain the determination of “sitting on the bench for ten years. From material formulation to biaxial stretching process, from aperture control to coating technology breakthrough, Enjie has overcome the technical threshold of wet diaphragm step by step. Today, Enjie’s research and development is undertaken by the Global Research Institute in Shanghai, with a team of more than 500 people from China, the United States, Japan, South Korea and other countries. It has forward-looking technology research institutes, product development centers, process technology development institutes and other institutions, covering the entire chain of materials, processes, equipment and testing. As of February 2026, Enjet has obtained a total of 512 authorized patents, of which 51 are international patents and 318 are under review. The average annual R & D investment is about 0.7 billion yuan.
Enjie attaches great importance to the construction of talent team, and continues to tap and cultivate potential talents from. In 2025, a number of key members of the company have been promoted to key positions in the production base and headquarters functional departments, injecting new vitality into the organization. Relying on the group’s domestic and overseas multi-base, multi-business platform advantages, Enjie shares for employees to create a cross-field, cross-regional diversified development path, not only broaden the staff career growth space, but also enhance the organization’s resilience and synergy. Through the two-wheel drive of “internal training and external introduction”, Enjet has built a talent echelon with reasonable structure and diversified capabilities, providing talent support and intellectual guarantee for promoting high-quality business development.
In the Enjie base in Yuxi, Yunnan, the scene of intensive shuttling of workers in the traditional manufacturing industry is almost invisible. Instead, automated equipment runs in a highly clean environment. This is an intelligent production base designed by Enjet based on the “lighthouse factory” with the highest standard of industrial 4.0. The core is a digital “super brain”. Engineers only need to operate the computer in the control center to monitor and allocate the production data and rhythm of the whole production line in real time. Behind the digital management, Enjie has carried out digital transformation in research and development, production, supply chain, sales and service, and has constructed a business intelligence analysis report covering procurement, inventory, production and finance. Through 147 indicators to analyze management problems with data, Enjie has promoted all employees to form a “data-driven decision-making” working habit.
Enjie shares believe that “the new quality productivity of the diaphragm industry is to take scientific and technological innovation as the engine, green and low-carbon as the background, intelligent manufacturing as the support, global synergy as the path, to promote the industry to high quality, high toughness, high value-added direction.”
Leading the future through the cycle
Enjet’s shares, which have become the world’s diaphragm leader, are not so comfortable. In December 2021, Enjie shares established Hunan Enjie Frontier New Materials Technology Co., Ltd. (hereinafter referred to as “Hunan Enjie”), officially cut into the field of solid-state battery materials. Enjie has chosen the most potential sulfide route, which is considered to be the mainstream path for solid-state batteries due to its ultra-high ionic conductivity and good processing performance. Japan’s Toyota, South Korea’s LG, as well as the domestic Ningde era, BYD, Zhongchuang Xinhang and Guoxuan Gaoke and other head enterprises have a layout.
Facing the solid-state battery technology known as the “next generation battery”, there is no lack of “subversion theory” inside and outside the industry. Some people worry that the popularity of solid-state batteries will make the diaphragm industry zero overnight. The view of Enjie shares is very clear, “semi-solid still need diaphragm, all-solid still need time. Semi-solid-state batteries still use diaphragm, Enjie related products have been bulk supply of Weilan new energy and other head enterprises; all-solid-state battery scale, industrialization still need a long time, is expected to be mainly used in deep space, deep sea and other high-end segments before 2030, the short term will not constitute a subversion of the existing diaphragm market.”
Li Xiaoming said, “A true industry leader must dare to revolutionize himself, so we started developing solid-state electrolytes and lithium sulfide very early. If the future really enters the solid-state era, Enjie will still be the core supplier in this field. Our vision has never been to hold a diaphragm, but to become the world’s leading new energy materials company.”
At present, the 10-ton pilot line of high-purity lithium sulfide products from Hunan Enjie has been completed, and the products have been recognized by the head customers, realizing small batch shipment of high-purity lithium sulfide. Solid electrolyte 10-ton production line has been put into production and has a ton-level shipping capacity, new electrolyte products have been sent to domestic and foreign head battery enterprises. In terms of electrolyte membrane, ultra-thin high-toughness products are in the stage of research and development and sample delivery, and the conductivity and other indicators belong to the industry-leading level.
Enjie has reached strategic cooperation with Weilan New Energy, Guoxuan Gaoke, Enli Power and other enterprises. In 2025, Enjet shares and Beijing Weilan New Energy signed a procurement framework agreement, agreed on the purchase share of 2025-2030, and signed an agreement with Enli Power to jointly develop a high-performance electrolyte diaphragm suitable for solid-state batteries.
The forward-looking technology layout will eventually land into a global market map. In Enjie’s view, the real industry leader must not only define the future technically, but also occupy a core position in the global industrial chain. In the face of the increasingly complex international trade environment, Enjet’s strategy is to “globalize localized services” and deeply integrate into the global market with localized production capacity, teams and services.
At present, the global layout of Enjie shares has begun to take shape. Its U.S. base project is progressing steadily; the Hungarian base has partnered with local head companies and is starting to supply overseas customers. By hiring a local team and strictly complying with local regulations, Enjet will ensure the steady development of its overseas business.
from a local enterprise in Yuxi, Yunnan province to a leader in the global diaphragm industry, enjie shares have officially entered the lithium battery diaphragm track since 2010 under the leadership of chairman Li Xiaoming. after 16 years of hard work, from one diaphragm factory to the current 13 diaphragm factories, based on China to the world, the domestic diaphragm market share in the world has been increased from 4% to more than 93%, become the world leader in lithium battery diaphragm industry.
The path taken by Enjie is a sample of the rise of China’s new energy industry chain. In Li Xiaoming’s view, “Let more new energy vehicles use a safe and stable Enjie diaphragm. This is not only a business, but also our generation’s mission and responsibility for global sustainable development”.
