Explain the status quo of research on waste lithium-ion battery recovery patent layout

　　Author ：Iflowpower – Portable Power Station Supplier

With the increasing shortage of global resources and the urgent need of environmental protection, new energy is developed to reduce resource consumption and reduce environmental pollution is gradually become a wide range of consensus. With the continuous development of the new energy industry, the amount of lithium-ion battery is getting bigger and larger, and my country is already the world's battery production and consumption. In 2013, the national level introduced 2013-2015 to buy new energy car subsidies standard related policies, new energy vehicles develop rapidly; 2015, affected by national subsidy policy, new energy automotive production and sales emergence rising.

With the explosive rising in my country's new energy auto market, the power of the new energy car heart is also the amount of bovy boat. With the new energy vehicle power lithium battery, the use of 5-10 years, the first batch of power lithium battery recycling market will begin to appear in 2018. A large number of lithium-ion batteries will be scrapped, and the recycling work is imperative.

In order to promote the recycling of dynamic lithium battery, in order to strengthen new energy vehicle power storage battery recycling management, standardize the development of the industry, February 26, 2018, Notice of the Seventh Party of the Ministry of Industry and Information Technology, the Ministry of Science and Technology, the Ministry of Environmental Protection, the Ministry of Communications, the Ministry of Commerce, the Quality Supervision, Inspection and Quarantine, and the Energy Administration of New Energy Automobile Power Battery Recycling Management Interim Measures. Recycling of waste lithium ion dynamic lithium batteries can not only promote the development of my country's circular economy, but also has a significant significance about the construction of ecological civilization in my country. At present, the recycling and re-use problem of lithium-ion power lithium battery has become the focus of concern in the whole industry.

Waste lithium-ion battery recovery briefly lithium ion battery includes positive electrode, negative electrode, diaphragm, electrolyte and battery housing, etc., many kinds of pollutants contained in waste lithium ion power lithium batteries. Containing contaminants contain heavy metal compounds, lithium hexafluorophosphate (LiPF6), benzene, ester compounds, etc.

(see Figure 1), difficult to degrade by microbial degradation. Once the materials such as electrode materials in batteries have entered the environment, the heavy metal ions, organic matter, carbon dust, fluoride, etc. will cause serious environmental pollution.

Among them, the positive material can cause heavy metal pollution, pollute water and soil; negative electrode materials can cause dust pollution; electrolyte will cause fluorofluid and organic pollution; diaphragm material can cause white pollution. Moreover, copper, nickel, cobalt, manganese, lithium, etc., viable metals, will also cause waste of resources.

在废旧锂离子电池回收的过程中，首先要对废旧锂离子电池的部件进行分解，然后对各部件分别进行回收利用（Areviewofprocessesandtechnologiesfortherecyclingoflithium-ionsecondarybatteries，JinqiuXuaetal.，JournalofPowerSources，第177卷，2008年0一月十Four days, 512–527 pages). Waste lithium ion battery recycled includes recycled metal and regenerated lithium ion battery materials.

The focus of the current recycling is that the positive material is high, the price is high, and the economic value is large. However, there are fewer recovery of other components in the battery, such as diaphragm, electrolyte, negative electrode active material. Among them, the recovery step of the metal includes lithium ion battery pretreatment, secondary treatment, depth processing, and separation purification.

The regenerated lithium ion battery preparation step includes pretreatment of lithium ion battery, and secondary treatment by supplementing a lithium source, iron source, etc., baked to a lithium ion battery material. The pre-processing step is important to include depth discharge processes, broken, physical sorting, refers to a series of work to be done before the electrode material in the battery, including release residual electricity, deactivation of waste, removal packaging, mechanical dismantling The outer casing of the battery and the pulverization of the battery, etc.

The diaphragm, electrolyte, and housing can be recovered by physical sorting, and the positive and negative electrical electrolysis is obtained in the crushing process, due to mechanical physical use, the partial negative electrode material is detached from the substrate, but most of the materials are also attached to the substrate. Therefore, it is necessary to perform secondary processing on the broken battery debris. The purpose of secondary treatment is to achieve complete separation of positive and negative active materials and substrates.

Since the negative electrode binder generally uses a water-soluble binder, the bonding use between the negative electrode active material and the copper foil is weak, and the negative electrode debris is placed in aqueous solution, and the strong stirring can achieve the complete separation of both. The node binder is a mixed solution of PVDF and N-methylpyrrolidone (NMP). Due to the amount of solvent NMP, thereby causing strong bonding use of the positive electrode material and the aluminum foil, difficult to separate.

Therefore, during the secondary treatment, it is important to achieve the positive electrode material and the aluminum foil, the battery debris obtained after the secondary treatment, and the aluminum foil and positive material are obtained after filtration. Aluminum foil can be used directly for smelt recovery, and the positive electrode material is to recover the price of metal. The purpose of deep treatment is to recover heavy metal ions (CO2 +, Li +, Ni2 +, Mn2 +, Cu2 +, Al3 +), etc.

Deep processing steps Important include leaching and separation pure two processes. The leaching process is an important acid immersion and microbial leaching. The separation and purification process is important, and the extraction method and electrochemical method are used.

Based on the Vientiane Cloud Operation Platform, this paper analyzes the distribution of lithium-ion batteries at home and abroad, hopes to take this to the leader in the patent technology owner of the low-tee, and what they do my country's patented technology layout. (1) Technical development trend Domestic lithium-ion battery recovery patent technology begins in 1999, during 1999-2011, the annual patent application is less, no significant increase, indicating that it is still in the technical germination stage, it is important to explore And research, technical output is also more poor (see Figure 2). With the development of lithium-ion battery recovery technology, in 2011, the number of patent applications has increased, especially with the introduction of a series of new energy-related policies for new energy policies since 2013, the government began to support lithium-ion batteries.

The company's innovative development has enabled lithium-ion battery related research. With the active activity of lithium-ion batteries, the technical output of lithium-ion battery recovery has also increased rapidly, and the number of patent applications has increased. Due to the lag of patented data, 2016 with 2017 is for reference only.

But basically, the amount of patent applications recovered by lithium ion batteries will remain a large rise. As can be seen from Figure 2, the amount of application for waste lithium ion battery has not yet appeared, indicating that this field technology is emerging technology, and is in high-speed sustainable development. Confused foreign countries, the development of lithium-ion battery recovery technology has been more early, but the application has been less, although since 2011, the application has increased, but its application is far less than my country.

This shows that although the research and development of the lithium-ion battery recovery is later in foreign countries, with our government attaches importance to the research and development of lithium-ion batteries, it is actively invested in the development of huge summons. The domestic lithium-ion battery recovery patent application is significantly higher than abroad Technology is growing. (II) Domestic Important Patent Applicant Distribution Figure 3 is the number of patent applications in China's important applicants in my country.

Lithium-ion battery recycling sector is ranked in front of the previous sequential in the front of Hefei Quan Gaoke Power Energy, Bangpu Circular Technology, Central Plains University, Greenmeal, National Power Grid, Lanzhou Institute of Technology, Tianqi Lithium, Henan Normal University, China Aviation Lithium Electric, Tianjin Institute of Technology University, Shanghai Qiumei Energy, my country Institute of Process Engineering and BYD Shares. In the field of lithium-ion battery recycling, universities and research institutes, and the company's research and development enthusiasm and research and development strength are very strong, and there are obvious outputs. In addition, Hefei Qixuan, the highest patent application, is not only in the field of waste lithium-ion battery recycling, but also has a large patent application in other fields of lithium-ion batteries, and is far ahead of lithium-ion battery technology research.

(3) The application trend analysis of domestic important applicants has been seen from the application trends of important applicants. It is important to apply in 2011. After 2011, there is a very small number of patent applications, which is consistent with the aforementioned analysis (see Figure 4).

Among them, Hefei Guoxuan's patent application is more concentrated, most concentrated in 2016, due to some of the 2017 patent applications have not been disclosed, the application trend of Hefei Guoxuan in 2017 is temporarily unable to do accurate judgment. In addition, without considering the emergence of explosive applications in 2016, it can be learned that the application situation in this field has shown a more dispersed characteristics, which also illustrates applicants who have not occupied monopoly in this area. The application situation in this area has shown a more dispersed characteristic, which also illustrates applicants who have not occupied monopoly in the field.

(1) Recycling of waste lithium ion batteries Recycling for recycled metal and regenerated lithium ion battery materials. From Figure 5, it is known that the current domestic recovery of metal is higher than that of the positive electrode material. This is important because the regeneration method of the positive electrode material is more complicated, the technical difficulty is high, and the energy consumption is high.

(2) Application for each technical branch in Figure 6, the pre-treatment involves pretreatment and secondary treatment of waste lithium ion batteries, including disassembly of waste lithium ion batteries, and positive active materials, collective fluids, electrolytes, and Separation of diaphragm or the like, during which, the recovery of electrolyte, collective body, and diaphragm can be realized. Metals include recovery with lithium elements and other metal elements. Negative electrode is important to repair regenerative methods for negative electrode materials such as graphite.

The electrolyte is important to include an electrolyte by recovering apparatus for electrolyte, and to obtain an electrolyte by preprocessing and secondary treatment of waste lithium ion batteries. The importance involves how to effectively restore the diaphragm. Regeneration of regeneration is the regeneration of the positive material.

As can be seen from Figure 6, there is currently an important concentration of waste lithium-ion battery recycling in pretreatment and secondary treatment, especially how to achieve dismantling of waste lithium-ion batteries, and how to achieve effective separation of positive and negative active materials. Fluid, electrolyte and diaphragm. There are not many patent applications for metal recovery and positive regeneration.

The most valuable and technical difficulties of waste lithium-ion batteries are the recovery of metals and the regeneration of the positive material, and the research on this aspect is relatively small, this shows that the domestic research is still in the initial stage of the study. Among them, in the difficulty of the technical difficulty of waste lithium-ion battery, Green Mei, Lanzhou University of Technology and Henan Normal University have the largest application, especially Lanzhou University of Technology and Henan Normal University, and its research is important in regeneration. This shows that due to the high difficulty of recycling of waste lithium ion batteries, its important research and development is still concentrated in colleges and universities.

Although Hefei Guoxuan is relatively large, it is important to have less research on the pretreatment, secondary treatment and metal recovery of waste lithium-ion batteries. Other applicants are equally patent applications for preprocessing and secondary treatment of waste lithium-ion batteries. As can be seen from Figure 7, the research and development of domestic waste lithium-ion batteries is currently concentrated in highly difficult pretreatment and secondary treatment.