As the key packaging material of soft pack battery, the quality of aluminum-plastic film is related to the quality, performance and life of soft pack battery. Limited by the performance of aluminum-plastic film, the advantages of flexible battery can not be brought into full play, which limits the large-scale application of flexible battery in the field of power and energy storage to a certain extent.

According to the data of the Institute of lithium battery research (GGII), the total installed capacity of domestic batteries from January to September reached 42.31gwh, an increase of 47% year-on-year. Among them, the installed capacity of soft pack battery is 0.365gwh, with a year-on-year increase of 1%, accounting for 8.63% of the total; Square batteries still dominate the mainstream, with an installed capacity of 35.54gwh, an increase of 64% year-on-year, accounting for 84% of the total.

According to Xia Wenjin, chairman and general manager of Suzhou lithium shield, from the current shape of power batteries, square batteries account for the largest share, followed by soft packs in the market. If soft pack batteries want to benchmark square batteries, they must meet several factors:

First, it can realize simple substitution in form, reduce product cost and use cost, and improve CTP value;

The second is to innovate technology to solve the performance of aluminum-plastic film, the bottleneck of safety technology and the technology improvement at the end of the supply chain;

Third, innovate the comprehensive experimental solution of multi factor environmental simulation, improve the life prediction ability of soft pack battery and give full play to its comprehensive performance, and solve the short board bottleneck of square battery;

Fourth, in the design stage of the flexible battery, the application conditions of the echelon utilization of the power battery and the requirements of long life are considered, the closed-loop problem of the industrial chain of the flexible battery is solved, and the green energy circular economy model of the flexible battery is established and realized.

"To promote the market share of flexible power batteries is the industrialization process of high safety and high specific energy solid-state batteries. To establish and realize the green energy circular economy model of flexible power cells, domestic aluminum-plastic film enterprises and their industrial chains have the obligation and responsibility to carry the banner of aluminum-plastic film localization instead of import." Xia Wenjin emphasized.

However, looking at the development of domestic aluminum-plastic film, although some achievements have been made in replacing imported aluminum-plastic film in 3C digital field, the replacement progress in power battery field is very slow.

Xia Wenjin believes that the fundamental reasons for the slow localization and replacement of aluminum-plastic film are: 1. The domestic industrial chain enterprises have insufficient research on aluminum-plastic film, and the market mainly depends on the technical route and experience of Japanese and Korean enterprises; 2. Domestic aluminum plastic film material supply system is lacking; 3. Insufficient market recognition; 4. The technology and cost advantages of square battery have not been broken through.

Based on this, Suzhou Lidun has taken the third aluminum-plastic film technology route completely different from the traditional technology route of Japan and South Korea, that is, through the self-developed non-polar microwave anchoring technology platform, we can produce aluminum-plastic film products with excellent deep drawing, high barrier, insulation, flame retardancy and corrosion resistance.

The difference of non-polar microwave anchoring technology lies in that it is different from the traditional thermal curing methods of dry method (glue bonding) and thermal method (adhesive film bonding). Using the principle of "nail nailing", micro nails are hit into the interfaces of nylon, PP and aluminum foil respectively through the method of plasma, and then the nails of each interface are connected through microwave irradiation to form a chemical anchor net, which forms an integration of each interface.

This structure can fundamentally solve the problem of longitudinal and transverse consistency of aluminum-plastic film after deep drawing, so as to achieve high deep drawing, high barrier, insulation and long-term corrosion resistance.

Xia Wenjin introduced that the technical route has achieved a full range of technologies such as soft pack battery packaging materials, processes and equipment made in China, which has truly achieved full localization, and has applied for 53 national patents and 32 authorized patents.

In terms of production capacity, from small-scale test, medium-sized test to large-scale test, the company has completed the construction of two production lines with a design capacity of 15million square meters, which has been put into operation in May this year. The production capacity target for next year is to form 50million-80million square meters.

Statistics show that Suzhou Lidun, founded in 2015, is a leading technology innovation enterprise invested by China Huarong assets and Hubei high tech investment. It mainly provides high-performance and safe packaging differentiation solutions for automotive power batteries, energy storage batteries, high-end consumer electronics batteries, high rate batteries, polymer batteries, solid-state batteries, etc.

The "13th five year plan" key R & D project in Jiangsu Province, which is jointly funded by Suzhou lithium shield and Southeast University, is currently the only key technology project undertaken for aluminum-plastic film of high-capacity and high-power density lithium batteries in China.

In addition, the company also signed strategic cooperation agreements with Chinalco and Central South University. As the largest alumina / primary aluminum producer in China, Chalco has a deep technological accumulation dimension in aluminum foil; Central South University also has the most cutting-edge research and exploration in aluminum, and the innovative process route of Suzhou lithium shield has also been recognized and supported by academician experts.

December 16-18,"Liyuanheng naming • 2019 high tech lithium battery & electric vehicle annual meeting"It will be held at Hyatt Regency Shenzhen airport. The theme of this annual meeting is"The darkest hour and great future of global electrification"。 At that time, the upstream and downstream enterprises of the 500 + lithium battery industry chain and the senior executives of the 800 + enterprises will gather together to discuss the muddy and smooth road of the lithium battery industry.

At that time, Xia Wenjin, chairman and general manager of Suzhou Lidun, will also share with the participants the research and development ideas of the third technical route of aluminum-plastic film, localization solutions, the company's strategic planning, as well as forward-looking perspectives on the future competition pattern of aluminum-plastic film, and work together with upstream and downstream enterprises in the industrial chain to face the challenges and opportunities brought by the cold winter of the new energy vehicle market.

"Don't worry, use anchors. The mission of Suzhou lithium shield is to be the shield of lithium battery, and is committed to building aluminum-plastic film as a technical platform for the safety and performance of a new generation of lithium battery." Xia Wenjin emphasized.

Article source:High tech lithium power grid