Power battery recovery hard core technology flow! Dry and wet method to disassemble the cascade and make use of the profit space calculation is all here!

In the previous article, we have mentioned the huge space of power battery recovery, this article is mainly about the purpose and technical route of battery recovery.

Batteries contain a variety of harmful substances, random waste will have a great impact on the ecology.

A large number of decommissioned batteries will pose a potential threat to the environment, especially the heavy metals, electrolytes, solvents and all kinds of organic excipients in power batteries, if they are discarded without reasonable disposal. It will cause great harm to soil, water and so on, and the restoration process will take a long time and high cost, so the need for recovery is urgent.

Lithium batteries usually contain the following table of substances, according to the 2011 edition of the United States Hazardous substances list data, Ni, Co, phosphide score of more than 1000, is considered to be a high-risk substance. If waste lithium ion batteries adopt common waste treatment methods (including landfill, incineration, composting, etc.), metals such as cobalt, nickel, lithium, manganese and inorganic and organic compounds will cause serious pollution to the atmosphere, water and soil. It's very harmful.

If the substances in waste lithium-ion batteries enter the ecology, they can cause heavy metal nickel and cobalt pollution (including arsenic), fluorine pollution, organic pollution, dust and acid-base pollution. The electrolytes and their conversion products of waste lithium-ion batteries, such as LiPF6, LiAsF6, LiCF3SO3, HF, P2O5, solvents and their decomposition and hydrolysis products, such as DME, methanol, formic acid, etc., are toxic and harmful substances, which can cause personal injury and even death.

The economic value of battery material recovery mainly lies in the re-mining of material regeneration value and energy value.

This includes three aspects:

1. After decommissioning on high-end appliances, lithium batteries can still meet the needs of some low-end appliances, usually electric toys, energy storage facilities, and so on. The recycling of lithium batteries can give more value to lithium batteries. Especially decommissioned lithium battery;

2. Even if the electrical properties can not meet the deeper use, but the relatively rare metals such as Li, Co, Cu still have the value of regeneration;

3. Because of the great difference between partial metal reduction energy consumption and metal regeneration energy, such as Al, Ni, Fe, metal recovery has economic value in energy consumption.

Different types of lithium batteries contain different kinds of metals and their ratios. One ton of traditional consumption lithium cobalt battery corresponds to about 170 kg cobalt metal, but in copper, aluminum and lithium, the content is mostly similar. Therefore, overall, the recovery value of lithium cobalt acid batteries will be greater than that of other categories, such as lithium iron phosphate batteries and ternary lithium batteries.

The cell accounts for 36% of the power battery cost, and 49% if the gross profit is deducted, and the cell cost is even higher in the consumer battery. In the cell, the cost of cathode materials rich in metal elements such as nickel, cobalt and manganese accounts for 45%.

At present, the process of resource recovery includes two stages: pretreatment and subsequent treatment.

Pretreatment is to put the waste lithium battery into salt water to discharge, remove the outer packaging of the battery, remove the metal steel shell to get the inner core.

The cell is composed of negative electrode, positive electrode, diaphragm and electrolyte. The negative electrode is attached to the surface of copper foil, the positive electrode is attached to the surface of aluminum foil, the diaphragm is organic polymer, and the electrolyte is attached to the surface of positive and negative electrodes, which is the organic carbonate solution of LiPF6.

The follow-up treatment link is to recover the high value components of all kinds of waste after disassembly and carry out battery material recycling or repair. the technical methods can be divided into three categories: dry recovery technology, wet recovery technology and biological recovery technology.

Dry recovery technology refers to the recovery of all kinds of battery materials or valuable metals directly without solution and other media, including mechanical separation method and high temperature pyrolysis method.

The dry thermal repair technology can repair the crude products recovered by dry method at high temperature, but the positive and negative electrode materials contain certain impurities, and the performance can not meet the requirements of new energy vehicle power battery. Mostly used in energy storage or small power battery and other scenarios, suitable for lithium iron phosphate battery.

Pyrometallurgy, also known as incineration or dry metallurgy, is the removal of organic binders from electrode materials by incineration at high temperatures, while redox reactions of metals and their compounds occur. The metals and their compounds with low boiling point are recovered in the form of condensation, and the metals in slag are recovered by screening, pyrolysis, magnetic separation or chemical methods. Pyrometallurgy does not have high requirements for the composition of raw materials, which is suitable for large-scale treatment of more complex batteries, but combustion is bound to produce part of the waste gas pollution environment, and high temperature treatment also requires higher requirements for equipment, at the same time, it is also necessary to increase purification and recovery equipment, and so on. The processing cost is high.

The wet recovery technology is to transfer metal ions from electrode materials to leaching solution by means of ion exchange, precipitation, adsorption and so on. Metal ions are extracted from solution in the form of salt and oxide, including hydrometallurgy, chemical extraction and ion exchange.

The wet recovery technology is relatively complex, but the recovery rate of lithium, cobalt, nickel and other valuable metals is high. The obtained metal salt, oxide and other products, high purity can meet the quality requirements of power battery materials, suitable for ternary batteries, but also the main recovery methods used by the leading technology recovery enterprises at home and abroad.

The main purpose of biorecovery technology is to convert the useful components of the system into soluble compounds and selectively dissolve them, so as to separate the target components from impurity components, and finally recover valuable metals such as lithium, cobalt, nickel and so on. At present, the biological recovery technology is not yet mature, such as the culture of high-efficiency bacteria, the cultivation cycle is too long, the control of leaching conditions and other key problems still need to be solved.

At present, the wet recovery process, which is more efficient and relatively mature, is becoming the mainstream technical route in the specialized treatment stage. Most of the leading domestic enterprises such as Greene and Bump Group, as well as AEA, IME and other international leading enterprises, mostly adopt wet process technology as the main technology for the recovery of valuable metal resources such as lithium, cobalt, nickel and so on.

The specific capacity of the cathode material recovered by wet method is better than that of the cathode material repaired by dry method.

For ternary batteries, compared with lithium iron phosphate, its battery life is shorter, 80% cycle life of ternary material battery is only 800 to 2000 times, and there is a certain risk of safety. It is not suitable to be used in the field of cascade utilization with complex application environment, such as energy storage power station, communication base station backup power supply and so on.

However, due to the presence of rare metals such as nickel, cobalt, manganese and other rare metals, the ternary power battery can theoretically achieve an economic benefit of about 42900 yuan per ton by disassembling and extracting materials such as lithium, cobalt, nickel, manganese, copper, aluminum, graphite, diaphragm, etc. It is economically feasible.

Taking the ternary 523 battery as an example, the contents of nickel, cobalt, manganese and lithium per ton of ternary battery are about 96,48,32,19 kg. At present, the average recovery of nickel, cobalt and manganese can reach more than 95%, and the recovery of lithium is about 70%. The market prices of lithium, cobalt, electrolytic nickel and electrolytic manganese are 900000 yuan / ton, 480000 yuan / ton, 100000 yuan / ton and 17000 yuan / ton, respectively.

The nickel sulfate, cobalt sulfate, manganese sulfate and other metal salts recovered from the power battery can continue to be processed to produce the ternary precursor, which has obvious value-added space.

Taking the production of nickel sulfate as an example, the cost of recovering and treating each ton of nickel through waste power battery is less than 40,000 yuan, while the cost of directly producing nickel ore is more than 60,000 yuan. The cost of obtaining metal raw materials through resource recovery is lower than that directly from mineral development, and the resource recovery of ternary battery has the significance of reducing the cost.

Considering that the ternary battery recovery enterprise sells it back to the downstream enterprise in the form of sulfate after dismantling the precious metal, the sales price should be lower than the market price in the form of pure metal, so it is assumed that it is sold at a discount ratio of 70% of the market price. The disassembly income of the ternary battery is 34000 yuan / ton, so the market scale of only the ternary battery is expected to reach 5.41 billion yuan by 2023.

In terms of cost, the recovery cost of ternary battery is mainly composed of production cost, all kinds of expenses and taxes and fees.

Among them, the composition of production (rough cost estimation) is mainly as follows:

Material cost (waste battery, liquid nitrogen, water, acid-base reagent, extractant, precipitant, etc.) 20000 yuan / ton;

Fuel and power costs (electricity, natural gas, gasoline consumption, etc.) 650 yuan / ton;

Environmental treatment cost (waste gas, wastewater purification and waste residue, ash treatment) 550 yuan / ton;

Equipment cost (equipment maintenance fee, depreciation fee) 500 yuan / ton;

The labor cost (operation, technology, transportation personnel, etc.) 400 yuan / ton.

The shared administrative expenses such as salaries and sales expenses such as sales personnel and packaging are about 400 yuan / ton, and the value-added tax and income tax are 4000 yuan / ton.

The total disassembly cost of the ternary battery is 26500 yuan / ton. According to the above income of 34000 yuan / ton, the disassembly profit is 7500 yuan / ton. It can also be seen from the above table that the corresponding net profit space will exceed 1 billion yuan in 2023.

Through the recovery of raw materials, nickel, cobalt, manganese and other metal elements can achieve a recovery rate of more than 95%, and the economic benefit is remarkable. Through resource recovery, nickel, cobalt, manganese and lithium salt can be produced, and even ternary cathode materials and precursors can be further produced, which can be directly used in the manufacture of lithium battery cells, which is of great significance to construct the closed loop of industrial chain.

Lithium Iron Phosphate Battery: huge potential for Cascade Utilization of 10 billion Market

For lithium iron phosphate batteries, in terms of disassembly and recovery, the cost of the most widely used wet recovery of lithium iron phosphate batteries is about 8500 yuan per ton, while the income of precious metal recycled materials is only about 8100 yuan. As a result, the borrowing loss is about 400 yuan per ton.

Therefore, the recovery of lithium iron phosphate battery is mainly through cascade utilization rather than disassembly. Cascade utilization can give full play to its residual value, maximize circular economy and reduce the construction cost of energy storage system.

Cyclic system of Cascade Utilization

Cascade utilization refers to the decommissioned power battery after testing, screening, reorganization and other links, once again used in low-speed electric vehicles, standby power supply, electric energy storage and other operating conditions are relatively good, low requirements for battery performance.

At present, the main areas of cascade utilization are still energy storage and peak regulation.

The cascade utilization process is first of all the screening of decommissioned power batteries, which are conservatively expected to be able to use 60% to 70% of the power batteries put into operation after 2014.

Then there is a series application, in which a set of power batteries removed from each electric vehicle is used as a separate unit, coupled with a medium and small power energy storage inverter to form a basic energy storage unit. Then a number of energy storage basic units are integrated to form a medium and large energy storage power system.

The third is charge and discharge management. The current "peak cutting and valley filling" project, taking the iron tower in China as an example, requires about 8800kWh (at present, the main lead-acid batteries with short service life, low energy density and low price). With the requirements of environmental protection and efficiency, the replacement of lead-acid battery will open a huge demand gap for the cascade utilization of power battery.

At present, the ladder utilization technology based on PACK (battery package, that is, multi-stage series-parallel battery module) + BMS (battery management system) is the mainstream choice.

The PACK process is divided into three parts: processing, assembly and packaging. Its core is to form a battery pack by connecting multiple single cells in series and in parallel through a mechanical structure.

Due to the need to consider the mechanical strength and system matching of the whole battery package in the process of operation, A large number of mature technologies such as thermal management, current control and detection, module assembly design and computer virtual development are needed to cooperate with each other, which is a high threshold link in the process of cascade utilization.

The main function of BMS battery management system is to intelligently manage and maintain each battery unit, prevent the battery from overcharging and overdischarge, and monitor the battery status in real time, so as to protect the battery life.

BMS is a collection of management system, control, display, communication and information collection module, which acts as a link between the whole vehicle, battery and the whole battery system. For battery manufacturers, BMS embodies the core technical competitiveness of manufacturers. For the cascade utilization of power battery, BMS determines the applicable scope, life and overall value of the reused battery.

In a narrow sense, cascade utilization only refers to the reorganization and reuse of batteries, but the current cascade utilization and recycling system of lithium iron phosphate battery has been formed, and its connotation has become a full-cycle, multi-level utilization around available resources.

When the vehicle enters the scrappage period (the service life of the average car is longer than the battery), it will experience:

(1) screening of high-performance batteries: automobile enterprises, automobile disassembly factories and some recycling enterprises will screen out the batteries with high consistency and relatively good performance in scrapped batteries by means of testing, and assign or entrust other enterprises to allocate batteries as battery packs. And then sold to the downstream to the Chinese iron tower as the representative of the ladder utilization enterprises.

(2) disassembly: for batteries in poor condition and no direct utilization value, most of them will be collected in the hands of third-party recovery enterprises, which will be disassembled and reused by physical or wet methods. The copper, aluminum, diaphragm and other raw materials will be extracted and sold directly, the cathode material powder and negative material powder of lithium iron phosphate battery will enter the repair stage.

(3) repair: the purpose of repair is to further purify the material powder of lithium iron phosphate in order to obtain a higher price. At the same time, the decommissioned battery after cascade utilization will also receive the process of disassembly / repair, so as to realize the multi-dimensional utilization layer by layer.

In the whole cycle process, the general recovery enterprise has three profit points, that is,

The main results are as follows: (1) sell batteries with good initial screening status and can be used directly;

(2) the sale of disassembled raw materials;

(3) the sale of repaired positive / negative electrode materials.

However, at present, the ladder utilization is due to both technical and commercial problems. From the technical point of view, due to the poor consistency and different life of the power battery, the data of the BMS system will deviate from the actual situation of the battery, so that the cascade utilization process will face the challenges of safety, product quality and so on.

From the point of view of commercialization, on the one hand, the degree of standardization of the products used in the ladder is relatively low, on the other hand, because of the different types of batteries, the number of batteries required for matching will be very large, so the screening, matching, and processing costs are still relatively high. Only a few enterprises with mature technology can obtain economic benefits.

Nevertheless, at present, a number of industry leaders have reached strategic cooperation agreements for research and application with downstream utilization enterprises such as Chinese iron towers. With the continuous introduction and implementation of various standards for power batteries, the consistency of batteries will be greatly improved. The close cooperative relationship will solve the application problem of cascade utilization in the future.

From the aspect of economy, the cascade utilization space of lithium iron phosphate battery is calculated.

Assuming that PACK+BMS technology is used for cascade utilization, the cost of PACK is about 0.3 yuan / Wh,BMS, 0.1 yuan / Wh, waste lithium iron phosphate battery recovery cost 0.05 yuan / Wh,. The total cost of lithium iron phosphate battery utilization is about 0. 45 yuan / Wh, and the benefit of step utilization is 0. 6 yuan / Wh.

Assuming that the energy density of lithium iron phosphate battery is 110 h / kg and the energy of recycling waste battery is reduced to 70%, the profit space of cascade utilization is expected to exceed 5 billion yuan in 2023.

Whether it is cascade use or disassembly, we can see a new blue sea, which will be opened up step by step in the next few years. Those who seize this opportunity will certainly make a lot of gains.