Ternary electrode material of regenerated sodium-ion battery as well as preparation method and application of ternary electrode material
Through the liquid phase transient peeling and high-temperature sintering, regenerated sodium ion electrode materials are prepared, which solves the high energy consumption and low efficiency problems of traditional recycling methods, and realizes the application of high-performance regenerated materials in sodium ion batteries, improving the capacity and stability of the battery.
Patent Information
- Application Number
- CN202510514243.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-23
- Publication Date
- 2025-07-29
AI Technical Summary
When recycling failed sodium ion battery materials, the process is long, the energy consumption is high, and the economic value is poor. The traditional wet recycling path will cause environmental pollution and waste of resources.
Through the liquid phase transient peeling and instantaneous decarbonization method, the ternary electrode sheet of the failed sodium ion battery is separated to obtain the active material, and sintered with sodium at high temperature to prepare regenerated sodium ion electrode materials to avoid the introduction of aluminum and fluorine elements and maintain the structural integrity of the material.
It achieves excellent electrochemical performance and stable structure of regenerated sodium ion electrode materials, improves the capacity and cycle stability of sodium ion batteries, and has a simple preparation method and low energy consumption, which is suitable for industrial applications.
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Abstract
Description
Technical Field
[0001] The present invention relates to a sodium ion battery ternary electrode material, in particular to a regenerated sodium ion battery ternary electrode material, and also to a preparation method and application thereof, belonging to the technical field of waste battery recycling. Background Art
[0002] Compared to lithium, sodium is abundant and inexpensive. With modern society's growing demand for diversified new energy systems, the development of sodium-ion battery energy storage systems has attracted widespread attention. Currently, my country has completed the deployment of several sodium-ion battery production lines, including those by Zhongke Haina, Weifang Energy, and Tianjin Industrial Energy. Some products have entered the market and have received widespread acclaim from users. However, similar to lithium-ion batteries, the production process of sodium-ion batteries produces a large amount of electrode flakes and scrap. Furthermore, due to their limited cycle life, sodium-ion batteries will eventually be retired after prolonged cycling. Both processes generate a large amount of spent sodium-ion battery material. Without a proper solution, spent sodium-ion battery powder will cause serious environmental pollution and waste resources. This is particularly true for ternary sodium-ion battery materials, which are rich in valuable elements such as nickel and copper. While traditional wet recovery methods can effectively extract the various sodium ion elements, they are lengthy, energy-intensive, produce large amounts of waste, and, due to the low price of sodium salts, yield low economic value. Therefore, it is of great significance to prepare ternary electrode materials by directly regenerating failed sodium battery ternary electrode materials. Summary of the Invention
[0003] In view of the shortcomings of the prior art, the first object of the present invention is to provide a ternary electrode material for regenerative sodium ion batteries, which has excellent electrochemical properties and good stability.
[0004] A second object of the present invention is to provide a method for preparing a ternary electrode material for a regenerative sodium ion battery. The method is simple, has a short process, is low-cost, and is suitable for industrial application.
[0005] A third object of the present invention is to provide an application of a ternary electrode material for a regenerative sodium ion battery. When used as a positive electrode material in a sodium ion battery, the material can improve battery capacity and cycle stability.
[0006] In order to achieve the above technical objectives, the present invention provides a method for preparing a regenerated sodium ion battery ternary electrode material. The method comprises the following steps: instantaneously stripping the liquid phase of a spent sodium ion battery ternary electrode sheet within 20 to 300 seconds, followed by solid-liquid separation to obtain an active material; then calcining the active material at 800 to 1000°C for 0.5 to 10 minutes for instantaneous decarbonization; and then adding sodium and sintering to obtain the active material.
[0007] The present invention firstly realizes the two-phase separation of the electrode material and the aluminum foil while retaining the intrinsic structure of the waste sodium ternary material as completely as possible through liquid phase instantaneous stripping, thereby avoiding the subsequent introduction of aluminum elements into the sodium ternary regeneration system. The stripping process is clean, efficient, and has low pollution. Here, it is necessary to control the stripping time within an appropriate range. If the stripping time is too short, the positive electrode material is difficult to remove from the copper foil; if the instantaneous stripping time is too long, the sodium ions will quickly dissolve into the liquid phase, causing serious damage to the electrolytic structure of the ternary material and making it difficult to directly regenerate; secondly, the present invention realizes the rapid removal of substances such as PVDF and acetylene black through instantaneous decarbonization, effectively avoiding the reaction of the fluorine element in the PVDF inside the residual material with the metal ions on the surface of the ternary sodium material, so that the fluorine element is introduced into the ternary sodium material, resulting in a serious decline in the performance of the regenerated material.
[0008] As a preferred solution, the liquid phase instantaneous stripping time is 60s to 120s.
[0009] As a preferred solution, the calcination time of the active material is 3 minutes to 6 minutes.
[0010] As a preferred solution, the liquid phase instantaneous stripping solution is at least one of an ethanol aqueous solution, a sodium salt aqueous solution, and pure water, more preferably an ethanol aqueous solution or a sodium salt aqueous solution.
[0011] As a preferred solution, the mass concentration of the ethanol aqueous solution does not exceed 80%.
[0012] As a preferred solution, the molar concentration of sodium ions in the sodium salt aqueous solution is not less than 3 mol / L.
[0013] As a preferred solution, the instantaneous decarburization atmosphere is an oxygen-containing atmosphere, which is air and / or oxygen.
[0014] As a preferred solution, in the process of sodium preparation, the sodium content in the decarbonization material is first detected, the molar amount of the missing sodium element is calculated according to the sodium content in the raw material of the failed sodium ion battery ternary electrode sheet, and then a sodium source in an amount of 1.05 to 1.3 times the molar amount of the missing sodium element is added to the decarbonization material.
[0015] Controlling the amount of sodium is beneficial to improving the comprehensive performance of the material. If the amount of sodium is too little, the sodium source will volatilize during the sintering process, resulting in the appearance of a sodium-deficient ternary phase, affecting the electrochemical properties of the directly recycled material; if the amount of sodium is too high, there will be more residual sodium in the recycled ternary material, causing the recycled material to decay faster and the stability to decrease relatively.
[0016] As a preferred solution, the sodium source includes at least one of sodium nitrate, sodium acetate, sodium hydroxide, and sodium carbonate.
[0017] As a preferred embodiment, the sintering is two-stage sintering.
[0018] As a preferred embodiment, the atmosphere during the sintering process is an oxygen-containing atmosphere. The oxygen-containing atmosphere includes air and / or oxygen.
[0019] As a preferred embodiment, in the two-stage sintering, the temperature of the first-stage sintering is 450 - 700 °C, and the time is 2 - 10 h; the temperature of the second-stage sintering is 800 - 1200 °C, and the time is 5 - 20 h.
[0020] As a preferred embodiment, the heating rate during decarburization and sintering is 2 - 20 °C / min.
[0021] The present invention also provides a regenerated ternary electrode material for sodium-ion batteries, which is prepared by the above method. This material has excellent electrochemical performance and strong stability.
[0022] The present invention also provides an application of the regenerated ternary electrode material for sodium-ion batteries, which is used as a positive electrode material for sodium-ion batteries. The sodium-ion battery using this electrode material has a high capacity and good cycle stability.
[0023] Compared with the prior art, the present invention has the following beneficial effects:
[0024] (1) The regenerated ternary electrode material for sodium-ion batteries of the present invention has excellent electrochemical performance and stable structure. When used as a positive electrode material for sodium-ion batteries, it can improve the capacity and cycle stability of sodium-ion batteries;
[0025] (2) The preparation method is simple, does not involve the use of acid-base drugs, realizes the short-process and low-energy consumption regeneration of failed ternary materials for sodium batteries, has low cost, short cycle, high economic benefits, and is suitable for industrial application. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 It is the XRD pattern of the regenerated electrode material prepared in Example 1 of the present invention.
[0027] Figure 2 It is the charge-discharge curve of the sodium-ion battery prepared using the regenerated electrode material in Example 1.
[0028] Figure 3 It is the cycle stability diagram of the sodium-ion battery prepared using the regenerated electrode material in Example 1. DETAILED DESCRIPTION OF THE INVENTION
[0029] The following examples are used to illustrate the content of the present invention, but do not limit the protection scope of the claims of the present invention.
[0030] The ternary material / powder of the failed sodium-ion battery used in the present invention is derived from the ternary powder of the failed sodium-ion battery, scraps, pole pieces, unliquid-injected sodium batteries, etc. purchased on the market.
[0031] Example 1
[0032] Ultrasonic the ternary failed pole piece of the sodium battery cathode material Na-Ni / Fe / Mn / CuO2 in an ethanol aqueous solution containing 50 wt% for 120 seconds. Then, filter the obtained mixed solution, and the obtained solid is suction-filtered 3 times with deionized water. The obtained active material is vacuum-dried overnight at 100 °C. Grind the obtained material into a uniform powder, and sinter it in an air atmosphere at 900 °C (heating rate: 10 °C / min) for 3 min to remove PVDF and conductive carbon in the material. After natural cooling, detect and calculate the sodium content in the decarbonized material, calculate the molar amount of the missing sodium element according to the sodium content of the ternary failed pole piece raw material, and then supplement sodium nitrate to the decarbonized material and grind it for 5 minutes until evenly mixed. The added amount of sodium nitrate is 1.15 times the molar amount of the missing sodium element. Finally, in an air atmosphere, sinter the mixture at 600 °C for 5 h, and then continue to sinter it at 1000 °C for 9 h. The heating rate during the sintering process is 10 °C / min. The sintered material is ground to obtain the recycled ternary material of the sodium battery.
[0033] Comparative Example 1
[0034] Prepare the recycled sodium-ion battery ternary electrode material by the method of Example 1, except that the ethanol aqueous solution is replaced by ethanol.
[0035] However, in this comparative example, it is relatively difficult to instantaneously peel the material, and the recovery rate is low. In the case of the waste pole piece in the same time, the pole piece peeling rate is only 10%, and it is difficult to achieve the efficient recovery of the waste ternary material of the sodium battery.
[0036] Comparative Example 2
[0037] Prepare the recycled sodium-ion battery ternary electrode material by the method of Example 1, except that the ultrasonic time in the ethanol aqueous solution is controlled to be 2 h.
[0038] Comparative Example 3
[0039] Prepare the recycled sodium-ion battery ternary electrode material by the method of Example 1, except that the sintering time (decarbonization time) for sintering to remove PVDF and conductive carbon in the material in an air atmosphere is controlled to be 12 min.
[0040] Example 2
[0041] Prepare the recycled sodium-ion battery ternary electrode material by the method of Example 1, except that the ethanol aqueous solution is replaced by pure water.
[0042] Example 3
[0043] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that the mass concentration of the ethanol aqueous solution was controlled at 80%.
[0044] Example 4
[0045] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that the ethanol aqueous solution was replaced with a 4 mol / L sodium chloride aqueous solution.
[0046] Example 5
[0047] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that the ultrasonic time in the ethanol aqueous solution was controlled at 20 s.
[0048] Example 6
[0049] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that the ultrasonic time in the ethanol aqueous solution was controlled at 300 s.
[0050] Example 7
[0051] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that the sintering temperature (decarbonization temperature) for removing PVDF and conductive carbon from the material by sintering in an air atmosphere was controlled at 800 °C.
[0052] Example 8
[0053] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that the sintering temperature (decarbonization temperature) for removing PVDF and conductive carbon from the material by sintering in an air atmosphere was controlled at 1000 °C.
[0054] Example 9
[0055] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that the sintering time (decarbonization time) for removing PVDF and conductive carbon from the material by sintering in an air atmosphere was controlled at 0.5 min.
[0056] Example 10
[0057] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that the sintering time (decarbonization time) for removing PVDF and conductive carbon from the material by sintering in an air atmosphere was controlled at 10 min.
[0058] Example 11
[0059] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that when supplementing sodium nitrate to the decarbonized material, the addition amount of sodium nitrate was controlled to be 1.05 times the molar amount of the missing sodium element.
[0060] Example 12
[0061] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that when supplementing sodium nitrate to the decarbonized material, the addition amount of sodium nitrate was controlled to be 1.3 times the molar amount of the missing sodium element.
[0062] Example 13
[0063] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that in an oxygen atmosphere, sintering was carried out to remove PVDF and conductive carbon (decarbonization) from the material.
[0064] Example 14
[0065] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that sodium carbonate was supplemented to the decarbonized material as a sodium source.
[0066] Example 15
[0067] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that the heating rate during the sintering process after sodium addition was controlled to be 20 °C / min.
[0068] Example 16
[0069] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that the heating rate during the sintering process after sodium addition was controlled to be 2 °C / min.
[0070] Example 17
[0071] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that the first-stage sintering temperature after sodium addition was controlled to be 450 °C.
[0072] Example 18
[0073] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that the first-stage sintering temperature after sodium addition was controlled to be 700 °C.
[0074] Example 19
[0075] The method of Example 1 was used to prepare the ternary electrode material for the recycled sodium-ion battery, with the difference that the first-stage sintering time after sodium addition was controlled to be 2 h.
[0076] Example 20
[0077] The ternary electrode material of the regenerated sodium-ion battery was prepared by the method of Example 1, except that the sintering time of the first stage after sodium addition was controlled to be 10 h.
[0078] Example 21
[0079] The ternary electrode material of the regenerated sodium-ion battery was prepared by the method of Example 1, except that the sintering temperature of the second stage after sodium addition was controlled to be 800 °C.
[0080] Example 22
[0081] The ternary electrode material of the regenerated sodium-ion battery was prepared by the method of Example 1, except that the sintering temperature of the second stage after sodium addition was controlled to be 1200 °C.
[0082] Example 23
[0083] The ternary electrode material of the regenerated sodium-ion battery was prepared by the method of Example 1, except that the sintering time of the second stage after sodium addition was controlled to be 5 h.
[0084] Example 24
[0085] The ternary electrode material of the regenerated sodium-ion battery was prepared by the method of Example 1, except that the sintering time of the second stage after sodium addition was controlled to be 20 h.
[0086] Example 25
[0087] The ternary electrode material of the regenerated sodium-ion battery was prepared by the method of Example 1, except that the atmosphere during the sodium addition sintering process was oxygen.
[0088] The regenerated materials, acetylene black, and PVDF binder prepared in each example and comparative example were all added with a certain amount of deionized water according to a mass ratio of 8 / 1 / 1 to prepare a uniform slurry. The obtained slurry was coated on the aluminum foil, and then placed in a vacuum oven at 120 °C for 12 h of drying. The obtained electrode sheets were cut by a slicing machine into small round pieces with a diameter of 1 cm to obtain the positive electrode materials, where the aluminum foil was loaded with more than 2 mg of the above composite material.
[0089] The positive electrode sheets, electrolyte, sodium metal, battery case, separator, etc. were placed in an argon glove box for battery assembly respectively. After sealing, the obtained battery was the assembled button battery.
[0090] After standing the button batteries for 12 h, they were placed on the BlueTEC test channel for electrochemical performance testing, where the current density was set to 2.0 C and the voltage range was set to 2.0 V to 4.0 V. The specific performance is shown in Table 1.
[0091] Table 1 Electrochemical performance of sodium-ion batteries prepared with the regenerated electrode materials of each example and comparative example
[0092]
[0093]
[0094]
[0095]
[0096] As can be seen from Table 1, in Comparative Example 1, ethanol pure solvent was used for liquid-phase exfoliation, and the obtained material had low performance. Moreover, the instantaneous exfoliation of the material was relatively difficult, the recovery rate was low, and the exfoliation rate of the waste electrode sheet was only 10% under the same time condition, making it difficult to achieve efficient recycling of waste ternary sodium battery materials. The data of Comparative Example 2 and Comparative Example 3 show that too long liquid-phase exfoliation time and decarbonization time will significantly reduce the material performance. Compared with the comparative examples, under suitable preparation conditions, the regenerated sodium batteries prepared in the examples of the present invention all have excellent electrochemical performance. In addition, the XRD pattern of the regenerated electrode material prepared in Example 1 of the present invention is shown in Figure 1 .
[0097] Figure 2 and Figure 3 are the charge-discharge performance diagrams of the sodium-ion battery prepared with the regenerated electrode material in Example 1. As can be seen from Figure 2 , when the current density is 2.0 C, the voltage is 2.0 V to 4.0 V, and the battery capacity is 106 mAh g -1 .
[0098] Figure 3 As can be seen, after the regenerated sodium battery of the present invention is cycled 200 times, the capacity retention rate is still above 80%, and the stability performance is good.
Claims
1. A preparation method of a ternary electrode material for a regenerative sodium-ion battery, characterized in that: The raw materials of the ternary electrode sheet of the failed sodium-ion battery are subjected to liquid-phase instantaneous stripping within 20 to 300 s and then solid-liquid separation to obtain the active material. Then, the active material is calcined at 800 to 1000 °C for 0.5 to 10 min for instantaneous decarbonization, and then sodium is added and sintered to obtain the product.
2. The preparation method of a ternary electrode material for a regenerative sodium ion battery according to claim 1, characterized in that: The solution for liquid-phase instantaneous stripping is an ethanol aqueous solution or a sodium salt aqueous solution.
3. The preparation method of a ternary electrode material for a regenerative sodium ion battery according to claim 2, characterized in that: The mass concentration of the ethanol aqueous solution does not exceed 80%.
4. The preparation method of a ternary electrode material for a regenerative sodium ion battery according to claim 2 or 3, characterized in that: The molar concentration of sodium ions in the sodium salt aqueous solution is not less than 3 mol / L.
5. The preparation method of a ternary electrode material for a regenerative sodium ion battery according to claim 1, characterized in that: The atmosphere for instantaneous decarbonization is an oxygen-containing atmosphere.
6. The preparation method of a ternary electrode material for a regenerative sodium ion battery according to claim 1, wherein: During the process of adding sodium, first, the sodium content in the decarbonized material is detected, the molar amount of the missing sodium element is calculated according to the sodium content in the raw materials of the ternary electrode sheet of the failed sodium-ion battery, and then a sodium source with a quantity of 1.05 to 1.3 times the molar amount of the missing sodium element is added to the decarbonized material.
7. The preparation method of a ternary electrode material for a regenerative sodium ion battery according to claim 1 or 6, characterized in that: The sintering is two-stage sintering.
8. The preparation method of a ternary electrode material for a regenerative sodium ion battery according to claim 7, characterized in that: In the two-stage sintering, the temperature of the first-stage sintering is 450 to 700 °C, and the time is 2 to 10 h; the temperature of the second-stage sintering is 800 to 1200 °C, and the time is 5 to 20 h.
9. A ternary electrode material for a regenerative sodium-ion battery, characterized in that: Prepared by the method according to any one of claims 1 to 8.
10. Application of a ternary electrode material for a regenerative sodium-ion battery according to claim 9, characterized in that: Used as a positive electrode material for sodium-ion batteries.