(Report Producer/Author: CITIC Construction Investment Securities, Lv Juan)
First, the ductility of lithium battery equipment process technology
1.1 Sources of product competitiveness of non-standard equipment enterprises
The core competitiveness of non-standard machinery enterprises comes from the precise control of specific processes. For non-standard equipment enterprises, their product competitiveness is composed of three major factors:
1) Bottom structure: PLC, vision system, servo motor, pneumatic components, robots and other parts are direct components of non-standard equipment products, this part of the parts is the basis of non-standard equipment product performance, but often purchased from the outside by non-standard equipment enterprises, so it is not the core competitiveness of non-standard equipment enterprises.
2) Process realization: designed by personnel who master the professional skills of non-standard mechanical design to form non-standard equipment that can achieve specific process effects (but do not require performance); there are not a few people who master the basic methods of non-standard mechanical design, but personnel with rich experience in specific processes are scarce.
3) Precision control of specific processes: through the continuous trial and error and adjustment of equipment, strive to improve the precision, efficiency and stability of equipment; the trial and error experience obtained through this step can be fed back to the "process realization" link, optimize its design and spare parts selection, and even realize process innovation and optimization; the link needs to rely on the understanding and accumulation of production and debugging personnel on the process and downstream customer needs.
1.2 The core process and business ductility of lithium battery equipment enterprises
Lithium battery production process
1) Pole chip production (battery cell front section): including stirring, coating, roller pressing, slitting and filming die-cutting links, corresponding to coating machine, roller press, slitting machine, die cutting machine and other equipment;
2) Battery cell assembly (middle section of the battery cell): including winding /lamination, encapsulation, drying, liquid injection links, corresponding to winding machine, laminating machine, battery cable assembly line and other equipment;
3) Cell detection (rear section of the battery cell): including chemical formation, capacity and testing links, corresponding to the cabinet, capacity cabinet and cell testing equipment, etc.;
4) Module &Pack line: After the completion of the manufacturing of single batteries in the above-mentioned pre- , mid-, and post-process processes, it is necessary to automate the assembly of the power battery module and pack, corresponding to the module assembly line and the Pack assembly line.
It is worth mentioning that laser processing technology runs through the front and middle sections of the battery cell, as well as the module & Pack line.
1.3 Examples of business extensions in key links
1.3.1 Coating: can be expanded in a wide range of areas
Core technology required for coaters
The core process technology required for lithium battery coater equipment is tension control technology, automatic deviation correction technology and drying technology.
The design, production and debugging of the coating machine need to meet the production requirements of different thicknesses, the thickness of the positive lithium battery aluminum foil is about 6-8 microns, the thickness of the negative lithium copper foil is about 4.5-6 microns, the diaphragm coating is only a few microns, and the graphene coating requirements are thinner; different thicknesses also need to develop different coating methods for customers to ensure that the coating thickness accuracy of the paste is controlled below 2 microns. In addition to process requirements, coating efficiency is an important criterion for measuring the technical strength of coating enterprises. The main ways to improve coating efficiency include increasing the operating speed and coating width of the coater.
1.3.2 Winding: mainly used in lithium batteries, capacitors
The winding process is mainly used in the field of lithium batteries and capacitors, and can be expanded in less directions
Tension control is the core technology that affects the advanced degree of winding machine.
Automatic guiding technology is also critical. The guiding system can ensure that the polar separator during the battery winding process is wound neatly, and the relative position between the positive / negative / diaphragm is accurate, and the current industry usually requires that the upper and lower deviations of the positive and negative pole plates or separators after the rolling are less than 0.5mm, and more than this value will have an impact on the deformation of the battery.
The winding process is mainly used in the field of lithium batteries and capacitors, and can be expanded in less directions. Winding process can be applied to lithium batteries, electrolytic capacitors, super capacitors and other fields, pilot intelligence, Chengjie intelligence and other winding machine leaders are cut horizontally into the lithium battery winding by the capacitor winding field. Looking forward to the future, the application field of winding process is limited, and the business development direction of related enterprises will be more concentrated in the field of large cylindrical power lithium batteries and energy storage lithium batteries.
1.3.3 Lamination: It is expected to extend to the fuel cell stacking link
Core process technology required for laminators
The core process technology required by the lithium battery laminating machine is tension control technology, cutting control technology, automatic deviation correction technology and efficient dust removal technology.
In simple terms, the lamination process is to stack the positive electrode sheet, diaphragm and negative electrode piece in order into a small cell cell, and then stack and parallel the small cell monomer to form a large battery cell. The lamination process is similar to the key technologies required for the winding process, except that the lamination process involves the cutting of the pole piece and the diaphragm, so it requires strong cutting control technology and efficient dust removal technology. (Source: Future Think Tank)
1.3.4 Laser: Highly versatile, can be widely extended to many high-end manufacturing fields
Laser cutting and welding processes are highly versatile and can be widely extended to many high-end manufacturing fields
In the production process of lithium batteries, the laser process is required for filming/die cutting, cell section welding, and module/pack section welding.
Production process: 1) the use of laser polar ear cutting can avoid powder loss and prevent safety problems; 2) the use of laser cleaning can remove residues and improve energy density; 3) the use of laser perforation can build ion channels and improve charging and discharging performance.
Battery cell, module, PACK assembly section: laser welding has the characteristics of non-contact and high speed, which can improve the automation rate and manufacturing efficiency, while ensuring the quality of the battery.
1.3.5 Assembly line: Non-standard production line integrators, the understanding of customer needs is the key
Assembly line: Non-standard production line integrator, the understanding of customer needs is the key
Assembly line suppliers are essentially integrators. The assembly line supplier designs non-standard production line solutions for downstream customers, and completes the secondary development of stand-alone equipment in each link and the integration of automation supporting equipment through the combination of procurement and self-production, so as to provide end customers with complete automation production line solutions.
The barriers to this link lie in the understanding of downstream customer needs, the level of automation of the production line and the ability to control costs. 1) Understanding of the needs of the next tourist: In the design of the assembly line, it is necessary to have a deep understanding of the production and manufacturing process of downstream customers, and with the iteration of downstream demand, it is necessary to continuously innovate, so it takes many years of technical exploration and customer accumulation; 2) The automation level of the production line: With the continuous improvement of labor costs, the downstream customers attach great importance to the automation level of the production line, and the automation level of the production line mainly depends on the connection speed and precision between the equipment in each link. The accumulation of AGV technology plays a key role in it; 3) cost control ability: In the pursuit of high efficiency, high precision and high automation rate of the production line, the control of cost, especially labor costs, is the most critical, and the working hours of design, production and commissioning personnel have a greater impact on the cost of the assembly line.
Second, the development trend of lithium battery equipment process technology
2.1 The 4680 battery was officially mass-produced, promoting the multi-link technology upgrade of lithium battery equipment
4680 battery: the laser link benefits greatly, which is good for head equipment manufacturers with technical reserves and high product performance
Tesla's 4680 battery has officially entered the mass production stage. In September 2020, Tesla released the 4680 battery, which has a charge and discharge efficiency of 6 times higher than that of traditional cylindrical batteries, and can increase the mileage of the whole vehicle by 16%, reduce the cost of electricity by 56%, and reduce the production cost by 69%. On February 19, 2022, Tesla announced that its California pilot plant had produced 1 million 4680 batteries in January, marking the official entry of 4680 batteries into mass production.
The 4680 battery is revolutionary in the design and production process. Tesla 4680 battery mainly applies the following three important technologies: 1) the use of electrodeless ears; 2) the negative electrode using silicon-based negative electrode; 3) the use of dry electrode process.
2.2 The dry electrode process has greatly changed the production process of lithium batteries in the front stage
Dry electrode process: extrusion, calendering (hot roller pressing) process instead of agitation, coating, roll pressing (cold, hot roller pressing)
Dry electrode technology is applied to Tesla 4680 batteries, which greatly changes the production process of lithium batteries. In February 2019, Tesla announced that it intends to spend $218 million to acquire Maxwell, one of the company's core technologies is dry electrode technology; in September 2020, Tesla announced that its 4680 battery will also use dry electrode technology. Dry electrode process is an innovation in the coating link of the production of the electrode, the traditional wet coating process needs to be mixed into a positive and negative electrode slurry, and then the slurry is coated on the front and back of the collector metal foil with a coater, and then the coated electrode is dried and rolled. Maxwell's proprietary dry process directly binds a small amount of adhesive and conductive agent to the positive/negative electrode powder without the use of solvents, forms a thin electrode material strip through the extruder, and then laminates the electrode material strip onto the collector metal foil to form the finished electrode.
2.3 The proportion of long thinning batteries is increased to promote the penetration rate of lamination machines
The winding process is to actively unwind the positive and negative pole plates and diaphragms, automatically correct the deviation, and roll them into a cylindrical or square shape with the diaphragm according to the process requirements. The lamination process is to stack the positive electrode sheet, diaphragm and negative electrode piece in order into a small cell monomer, and then stack the small cell monomer and connect it to form a large battery cell.
Advantages of the winding process: fast production speed, high battery consistency; advantages of the lamination process: the design of the soft pack battery produced is more flexible, the safety, cycle life, energy density is higher, but the production is more complex than winding, and the production speed and yield rate are relatively low.
In addition, for square cells, the winding process is more suitable for smaller size, larger thickness cells, while larger size, smaller thickness cells and special-shaped batteries can only have lamination process production.
2.4 Solid-state batteries mainly affect front and middle stage equipment
Solid-state battery: the semi-solid-state stage has little impact, and the all-solid-state stage will omit the diaphragm production and liquid injection links
Semi-solid-state batteries have entered the mass production stage, but the performance still needs to be improved; the commercialization of all-solid-state batteries still needs time. According to the different electrolytes, solid-state batteries are divided into three categories: polymers, sulfides and oxides; according to the different electrolyte states, solid-state batteries can be divided into all-solid-state batteries and semi-solid-state batteries. At present, semi-solid-state batteries have entered the mass production stage, such as Dongfeng Automobile E70 pure electric car equipped with mixed solid-liquid electrolyte lithium battery, entered the "New Energy Vehicle Promotion and Application Recommended Model Catalog" issued by the Ministry of Industry and Information Technology on December 29, 2021 (12th batch in 2021), is expected to be delivered in 2022Q1, but the system energy density of the model battery is 160wh/kg, the working condition is 426km, and the competitiveness still needs to be improved; Volkswagen, GM, Weilai and other domestic and foreign OEMs actively layout solid-state batteries, but it is expected that the loading application time is concentrated around 2030, and Chinese battery companies such as Ningde Times, Guoxuan Hi-Tech, and Qingtao are also actively developing solid-state batteries, and the commercial application time is concentrated in 2025-2030. Overall, there are still many technical difficulties in all-solid-state batteries, and commercialization still needs 5-10 years.
2.5 The pursuit of efficiency drives the integration of equipment and the downward trend of unit investment
Whole line & local whole line: improve the degree of integration of each link
Lithium battery equipment will develop in the direction of equipment integration. Equipment integration is one of the important means to improve equipment efficiency, the future lithium battery equipment front, middle and rear sections will be in their respective sections of equipment integration. Head equipment companies will also expand their product coverage with the help of the integration trend to achieve horizontal and vertical expansion.
Many comprehensive lithium battery equipment companies began to supply the whole line and the local whole line. Generally speaking, lithium battery manufacturers purchase the equipment required for each link from different suppliers, and the degree of integration between different links of equipment will directly affect the improvement effect of the level of production automation. With the concept of "turnkey production line project", comprehensive lithium battery equipment enterprises such as Pilot Intelligence, Win He Technology, and Li Yuanheng began to provide lithium battery equipment complete lines or local whole lines.
The whole line & local whole line is more attractive to OEMs and emerging battery factories in the field of batteries. Many advantages of the lithium battery full-line delivery model, such as:
1) It can reduce cumbersome business and technical docking and reduce operating costs;
2) It can improve the level of intelligentization, informatization and networking of the product line;
3) It can greatly shorten the equipment design, production and delivery cycle, and implement unified after-sales service;
4) The full set of equipment is purchased from the same equipment manufacturer, which can save costs to a certain extent. Under the background of the continuous boom in the new energy vehicle market, there are many new players in the power battery industry, including emerging battery factories such as Northvolt and ACC, as well as wholly-owned battery factories set up by vehicle manufacturers such as Volkswagen, which lack experience in the design, commissioning and maintenance of lithium battery equipment, so they are more inclined to choose the whole line supplier. However, it is often difficult to provide a complete line of comprehensive lithium battery equipment companies in all aspects of the leading technical level, first- and second-line power battery companies for high requirements for stand-alone equipment, will still give priority to the selection of excellent stand-alone suppliers.
3. Investment analysis
In summary: 1) lithium battery equipment process technology ductility: the front link, laser application link, and assembly line link process ductility is strong, and the long-term growth of related enterprises is better; 2) lithium battery technology development trend: new technology has different degrees of impact on the equipment end, of which the share of lamination routes is the most clear.
Excerpts from the report:
(This article is for informational purposes only and does not represent any of our investment advice.) For usage information, see the original report. ）
Featured report source: [Future Think Tank].