Focus on the industry chain: how to recycle power lithium-ion batteries?
2.1. The policy is being improved, and the standard and price are the core constraints
In December 2016, the Ministry of Industry and Information Technology announced the "Interim Measures for the Administration of Recycling and Utilization of Power Batteries for New Energy Vehicles" (draft for comments), which clarified that automobile production companies should assume the main responsibility for the recycling and utilization of power batteries. The Extended Producer Responsibility System (EPR) refers to extending the responsibility of the producer to the entire life cycle of the product, especially the post-consumer recycling and recycling stage, requiring the producer to take responsibility for the entire life cycle of the product, and to integrate production and production. The recycling is connected in series to improve the recycling rate.
In July 2018, seven departments including the Ministry of Industry and Information Technology and the Ministry of Science and Technology jointly issued the "Notice on Doing a Good Job in the Pilot Work of Recycling and Utilizing Power Batteries for New Energy Vehicles", and decided to launch the pilot program in the Beijing-Tianjin-Hebei region, Shanxi, Shanghai, Jiangsu, Zhejiang, Anhui, Guangdong, etc. 17 regions and my country's iron towers have carried out pilot work on the recycling of new energy vehicle power batteries, and determined the corresponding goals and tasks of each pilot region, which will help to establish a relatively centralized and cross-regional recycling system. With the successive introduction of relevant policies, the power lithium-ion battery recycling system will also be accelerated to improve. The launch of the pilot work of power lithium-ion battery recycling marks that my country's power lithium-ion battery recycling has entered a stage of large-scale implementation.
In July 2020, the Ministry of Industry and Information Technology announced the "Key Points for Energy Conservation and Comprehensive Utilization of Work in 2020", requiring to promote the construction of a new energy vehicle power battery recycling system; to carry out in-depth pilot work, and to accelerate the exploration and promotion of a recycling market with strong technical economy and environmental friendliness To develop a new energy vehicle model, cultivate a group of backbone companies for power battery recycling; research and formulate the "Administrative Measures for the Echelon Utilization of New Energy Vehicle Power Batteries", and establish a product evaluation mechanism for echelon utilization; ", improve regulations, and urge companies to speed up the fulfillment of traceability and recycling responsibilities. The improvement of the evaluation mechanism and laws and regulations of the power lithium-ion battery recycling system indicates that the framework of my country's power lithium-ion battery recycling system is becoming more and more mature.
Although the top-level design is gradually being improved, the current power lithium-ion battery recycling is constrained by the following three problems, making policy development more difficult:
1. The measurement standard of the residual value of the battery is difficult to estimate: the battery capacity of the power lithium-ion battery will gradually decay during the cyclic charge and discharge process, and when the decay falls below 80 percent , it will reach the retirement state. At present, the SOH (State-of-health) of the power lithium-ion battery has many meanings, including the meaning according to the capacity decay, the meaning of the remaining number of cycles according to the remaining discharge capacity, and the meaning according to the internal resistance. Therefore, policy makers have certain difficulties in the standard determination of the residual value of power lithium-ion batteries.
2. Metal price fluctuations affect the economics of material recycling: fluctuations in metal prices will ultimately determine the profit and loss of the power lithium-ion battery recycling market, and metal prices are affected by comprehensive factors such as resource supply, technological progress, and downstream markets. The production cycle, so metal prices are the decisive factor in the market-driven power lithium-ion battery recycling, which not only affects the business model of power lithium-ion batteries, but also affects the effectiveness of policy formulation and implementation.
3. Technical standards for cascade utilization: An important recycling method for lithium iron phosphate batteries is cascade utilization. Factors such as cascade utilization methods and safety have plagued the formulation of standards. Too high standards will cause the market for cascade utilization to shrink. It is not conducive to the long-term development of the echelon utilization market.
Therefore, these issues must be continuously summarized and feedbacked in practice to further improve policy standards and business models.
2.2. Recycling channels and recycling methods of power lithium-ion batteries
There are different participants and recycling paths in the recycling process of power lithium-ion batteries. This is mainly due to the differences in sales methods, forms of use, and ownership between different power lithium-ion batteries. At present, in my country, the recycling channels of power lithium-ion batteries mainly include small recycling companies, professional recycling companies, and government recycling centers. In recent years, in order to regulate the power lithium-ion battery recycling market, my country has successively issued relevant technical standards for the dismantling and recycling of power lithium-ion batteries:
Referring to the battery recycling paths of developed countries in Europe and the United States, power lithium-ion battery manufacturers often assume an important responsibility for battery recycling, while electric vehicle manufacturers and battery leasing companies among the participating entities play a role in cooperating with power lithium-ion battery manufacturers in recycling. According to the difference of participants in the path of power lithium-ion battery recycling from consumers to power lithium-ion battery manufacturers, it can theoretically be divided into three recycling routes.
The first recycling route is to recycle waste power lithium-ion batteries through electric vehicle dealers; the second recycling route is to recycle through battery leasing companies, and waste power lithium-ion batteries eventually flow to power lithium-ion battery manufacturers through the above two recycling routes ( Some manufacturers can also jointly form a manufacturer alliance) for recycling; the third recycling path eventually flows to third-party recycling companies, but third-party recycling companies rely on self-established power lithium-ion battery recycling outlets.
Specifically, according to the above three recycling routes, with reference to the reverse logistics theory, different power lithium-ion battery recycling route modes can be established. The recycling mode of power lithium-ion battery manufacturers represented by Japan (including electric vehicle dealers and battery leasing companies), and the recycling mode of industry alliances represented by European and American countries (power lithium-ion battery manufacturers jointly form a recycling alliance) And third-party recycling mode. Regarding different types of companies, due to the differences in the current situation of the company, different recycling path modes should be selected according to the actual situation to maximize the benefits.
2.2.1. Cascade utilization and metal recovery of lithium iron phosphate batteries
There are two major utilization methods after lithium iron phosphate battery recycling: cascade utilization and dismantling recycling. These two methods are not mutually exclusive, but complementary. The cascade utilization of waste batteries refers to the process in which power lithium-ion batteries can continue to be used in suitable working positions by repairing, refitting or remanufacturing when they reach the designed service life, and this process is generally the same level or downgraded application. form.
The dismantling and recycling of used batteries mainly refers to the dismantling of used batteries through chemical, physical or biological means and recycling of the available resources. In February 2017, the "Interim Measures for the Administration of Recycling and Utilization of New Energy Vehicle Power Batteries" issued by the state mentioned that battery production companies are encouraged to cooperate with comprehensive utilization companies. Carry out multi-level and multi-purpose rational utilization of waste power batteries.
The waste lithium iron phosphate power lithium-ion battery is recycled first in a cascade, and then dismantled and recycled, which will maximize the value of the battery after decommissioning. The performance of the power lithium-ion battery will attenuate with the increase of the number of uses, but when the power lithium-ion battery cannot meet the use standard of electric vehicles and is retired, its performance (battery capacity) often only drops to 80 percent of the original performance. When the battery performance is still maintained at 80 percent -20 percent , the retired power lithium-ion batteries can be used in the fields of low-power electric vehicles, grid energy storage, and home energy storage in turn after relevant testing and evaluation. And when the battery performance drops to 20 percent , it can be scrapped.
Under the current conditions, there are still great difficulties in the technology and market for the cascade utilization of retired power lithium-ion batteries.
(1) From a technical point of view, power lithium-ion batteries and energy storage batteries follow different technical standards, and the energy storage field has high requirements on the temperature performance of batteries, while partially retired power lithium-ion batteries may not meet the use requirements of energy storage batteries . The establishment of a battery life prediction model based on the analysis of the capacity decay mechanism is not perfect, resulting in difficulties in the evaluation and detection of gradient utilization of retired power lithium-ion batteries.
(2) From the market point of view, the establishment of a reverse logistics system for cascade utilization is more complicated, and there are many links involved. It is more complicated than direct physical, chemical, and biological dismantling and recycling, and consumers' psychological acceptance of cascade utilization batteries is relatively high. Low.
Compared with echelon utilization, the dismantling and recycling of retired power lithium-ion batteries is relatively mature in technology. Waste power lithium-ion battery treatment technology can be divided into physical, biological and chemical methods; physical methods include crushing flotation method and mechanical grinding method, but the separation efficiency is extremely low, and the recovery of valuable metals generally requires a follow-up treatment process ; Biological methods utilize microbial catabolism to achieve selective leaching and recovery of metal ions, but biological methods are basically still at the level of laboratory research and have a certain distance from large-scale applications.
The mainstream methods of dismantling and recycling are basically chemical methods, including three treatment processes, fire treatment, wet treatment, and electrode repair and regeneration. Fire treatment is a relatively primary waste treatment method. The important principle is that the high-temperature incineration of the battery after dismantling or crushing makes the organic matter in the battery oxidatively decompose, and the metal elements in the electrode materials and packaging materials are converted into stable metal oxides. Then separate and recycle. There are many related researches on wet processing technology. The important principle is to use acid solution and alkali solution to dissolve the electrode material, and then realize the separation and purification of each element in the liquid phase. The electrode repair and regeneration process is a treatment process that has emerged in recent years. The electrode materials in waste lithium-ion batteries are disassembled and separated, and treated with electrochemical or physical chemistry methods to restore their damaged structure and electrochemical performance, so that the material can be It can be used again for use or as a precursor for the preparation of new electrode materials.
2.2.2. Cathode material recovery and regeneration of ternary battery
At present, the technical route of ternary cathode material recovery and regeneration is mainly divided into the following two forms:
Physical repair and regeneration. For ternary cathode materials that only lose active lithium element, lithium element is directly added and repaired and regenerated by high-temperature sintering; for cathode materials with severe capacity decay and surface crystal structure changes, hydrothermal treatment and short-term high-temperature sintering are carried out. regeneration;
There are three main methods for metallurgical recycling: fire, wet and bioleaching. Among them, the fire method has high energy consumption, loss of valuable components, and the emergence of toxic and harmful gases; the biological leaching method has poor treatment effect, long cycle, and difficulty in culturing bacteria; in contrast, the wet method has high efficiency and reliable operation. , low energy consumption, no toxic and harmful gases and other advantages, so the application is more common.
2.3. Stone from other mountains, overseas power lithium-ion battery recycling mode
2.3.1. United States: Sound battery recycling laws and popularization of recycling knowledge
The recycling laws of used batteries in the United States are sound, and the system of relevant laws involves the federal, state and local levels. The three levels of laws complement and regulate each other, which makes the US battery recycling legal system perfect, comprehensive and specific.
At the federal level, the government regulates battery manufacturers and waste battery recycling companies by issuing licenses.
At the state level, most states have adopted battery recycling regulations proposed by the Battery Council International (BCI) to guide retailers and consumers by participating in pricing mechanisms for used battery recycling. For example, the New York State Rechargeable Battery Act and the California Rechargeable Battery Recycling Act require rechargeable battery retailers to recycle consumers' disposable rechargeable batteries at no charge.
At the local level, most cities in the United States have enacted electricity battery recycling regulations to mitigate the environmental hazards of used batteries. The US International Battery Council enacted the Battery Product Stewardship Act, which created a battery recycling deposit system to encourage consumers to collect and return used batteries.
There are many institutions in the United States to popularize the recycling knowledge of used batteries, and the national recycling awareness is generally strong. Take the National Battery Council International (BCI) as an example. As an authoritative third-party organization for battery recycling, the organization not only coordinates battery recycling in various states, but also details the popularization of battery recycling classification process and specifications. . BCI has a large number of documents and pictures on its official website to guide the battery recycling of individuals and companies, and, due to the different recycling methods of lead-acid batteries and lithium-ion batteries, BCI's process guidance even includes guidance for individuals and companies in recycling batteries. The distinction between lead-acid batteries and lithium-ion batteries.
2.3.2. EU: Producer Responsibility System plus Alliance System
The European Union was the first region to focus on battery recycling and to take measures. In 1991, the Directive on Batteries and Accumulators Containing Certain Hazardous Substances was introduced, which stipulated that these batteries should be recycled separately. The EU started early in the recycling of 3C batteries and lead-acid batteries, and has accumulated a lot of relevant relevant experience. In 2006, the waste battery treatment and recycling policy (2006/66/EC) was introduced, and a supporting system (extended producer responsibility system) was formed in which power lithium-ion battery production companies were responsible for the main body of recycling. Among them, in Germany, the awareness of producer responsibility and the division of labor for recycling are clearly the source of power. The emphasis on the recycling of power lithium-ion batteries has made Germany achieve remarkable achievements in the legal system, division of responsibilities, and technical routes for battery recycling.
The integration of responsibility, obligation and law is the foundation of Germany's complete power lithium-ion battery recycling system. The German government has promulgated the Recycling Act in accordance with directives such as the Waste Framework Directive (Directive2008/98/EC), the Battery Recycling Directive (Directive2006/66/EC), and the End-of-Life Vehicle Directive (Directive2000/53/EC). , "Battery Recycling Law", "Scrap Vehicle Recycling Law" and a series of relevant recycling laws.
Under the constraints of the relevant legal framework, the waste battery recycling system in Germany has a clear division of labor. Producers, consumers and recyclers in the industry chain have corresponding responsibilities and obligations. Batteries produced or imported by battery manufacturers must be registered with the government, downstream distributors are responsible for building a battery recycling network, and users are also obliged to return used batteries to the corresponding recycling agencies.
In addition, Germany places great emphasis on the "extended producer responsibility system" in power recovery. For example, Volkswagen, BMW and other new energy vehicle manufacturers actively recycle used batteries. Among them, BMW is committed to realizing the power lithium-ion battery value chain by establishing an industrial closed loop. In this value chain, from battery production raw materials, battery research and development, battery production, battery installation, to battery recycling to obtain valuable battery production raw materials , forming a closed loop to maximize the value of power lithium-ion batteries.
At the same time, BMW has also cooperated with Umicore, Vattenfall, Bosch, NextEra, etc. to explore the cascade utilization of retired power lithium-ion batteries in energy storage systems. BMW has successfully achieved energy storage grid stabilization by using the waste power lithium-ion batteries of the BMW i3 and MINIE prototypes. A total of 700 BMW i3 batteries are stored at its energy storage yard at the BMW Group's Leipzig plant, demonstrating that at the end of a car's battery life, profits can be made by giving the batteries a second life (as part of a sustainable energy model) .
2.3.3. Japan: Recycling mode of power lithium-ion battery under the development of "preparing for a rainy day"
Affected by the shortage of raw materials, Japan is a global leader in the recycling of used batteries. Battery recycling in Japan
