Dispersing agent for recycling waste solid electrolyte slurry and recycling method
By using polymer dispersant in solid electrolyte slurry for recycling, the recycling difficulties caused by the failure of slurry technology is solved, and efficient recycling and reuse of solid electrolyte slurry is achieved, thereby reducing energy consumption and cost.
Patent Information
- Application Number
- CN202510015940.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-06
- Publication Date
- 2025-04-22
AI Technical Summary
The prior art is difficult to effectively recover and reuse solid electrolyte slurry that has failed due to the characteristics of slurry technology, especially small particles that are difficult to separate and have high energy consumption.
Polyvinylpyrrolidone, polymaleic acid or polyacrylic acid are used as the recycling dispersant. By adding a dispersant to the waste solid electrolyte slurry, stirring, standing or centrifuging, and then drying and calcining at low temperature, the dispersant is self-crosslinked and easily removed during the process.
The extraction and reuse of active ingredients in solid electrolyte slurry is realized, the recovery rate and recovery rate are improved, energy consumption is saved and cost is reduced, and the dispersant is easily removed.
Smart Images
Figure SMS_1 
Figure SMS_2 
Figure SMS_3
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of solid electrolyte slurry recovery and reuse, and in particular to a waste solid electrolyte slurry recovery dispersant and a recovery method. Background Art
[0002] Solid electrolyte slurry is a new material used in solid-state battery processing, generally composed of solid electrolyte particles, solvents and additives. For non-aqueous solid electrolyte slurry, it is difficult to continue to use if water absorption occurs. For aqueous solid electrolyte slurry, it cannot be used if sedimentation and agglomeration occur. In addition, some electrolyte materials will also be affected by high temperature and deteriorate. In addition, solid electrolyte slurry has many risks of deterioration and failure. There are two reasons for the failure of electrolyte slurry. The first is the failure of slurry technical characteristics, including particle size, solid content, dispersant, etc. The second is the failure of the effective ingredient solid electrolyte in the slurry, including decomposition, deterioration, etc. The first failure is common, and the effective ingredient solid electrolyte can be extracted by slurry recovery for reuse. The second failure is uncommon and cannot be recycled or is difficult to recycle.
[0003] Aiming at the failure of slurry technical characteristics, the present invention provides a waste solid electrolyte slurry recovery dispersant and recovery method, which can extract the effective component solid electrolyte in the solid electrolyte slurry whose slurry technical characteristics have failed, can separate small particles, improve the slurry agglomeration efficiency, quickly realize solid-liquid separation, and has the advantages of improving the recovery rate, improving the recovery rate of centrifugation and filter pressing, saving energy consumption and reducing costs, and the dispersant is easy to remove. Summary of the invention
[0004] In view of the defects of the prior art, the present invention provides a dispersant and a recovery method for waste solid electrolyte slurry, which can extract the effective ingredient solid electrolyte from the solid electrolyte slurry in which the technical characteristics of the slurry have failed, can separate small particles, improve the efficiency of slurry agglomeration, quickly achieve solid-liquid separation, improve the recovery rate, and increase the recovery rate of centrifugation and filter pressing, save energy and reduce costs, and the dispersant is easy to remove, so as to overcome the defects in the prior art.
[0005] The technical solution of the present invention is achieved as follows: a waste solid electrolyte slurry recovery dispersant, the dispersant contains one or more of polyvinyl pyrrolidone, polymaleic acid, and polyacrylic acid.
[0006] The added amount of the dispersant accounts for 1% to 10% of the volume content of the electrolyte powder in the solid electrolyte slurry.
[0007] A method for recovering solid electrolyte slurry by using the above-mentioned waste solid electrolyte slurry recovery dispersant is that the method comprises the following steps:
[0008] S1. adding a dispersant to the waste solid electrolyte slurry;
[0009] S2, mixing and stirring the solid electrolyte and the dispersant, and then standing or centrifuging, and controlling the process temperature at 20°C to 40°C;
[0010] S3, separating and discarding the supernatant after standing, drying the precipitate after standing, and calcining at low temperature, the calcination temperature is 300° C. to 500° C., and the solid electrolyte powder is obtained after calcination.
[0011] The present invention has the following positive effects:
[0012] First, there are few existing technical designs for recovering electrolyte slurry, most of which recover certain elements from electrolytes. In addition, the traditional recovery method is centrifugation and filter pressing, but it is difficult to separate small particles and has high energy consumption. The patented dispersant can make the slurry agglomerate, quickly achieve solid-liquid separation, improve the recovery rate, increase the recovery rate of centrifugation and filter pressing, save energy and reduce costs, and the dispersant is easy to remove.
[0013] Secondly, the dispersant of the present invention plays a role in adsorbing electrolyte particles, and after capturing the electrolyte particles, the molecular dispersant will also self-crosslink, quickly settle under the action of gravity, significantly improve the recovery efficiency, and the dispersant can be completely removed in the later drying and calcining process. The dispersant has an anchoring group and can also adsorb solid electrolyte particles. Under the action of gravity, the force of the system gradually becomes uneven, and the long polymer chain cannot remain stable, thereby increasing the sedimentation rate of the slurry, which can improve the recovery efficiency, and the dispersant can also be completely removed after drying and calcining in the later stage. DETAILED DESCRIPTION
[0014] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0015] In the following description of the invention, it should be noted that the terms "upper", "lower", "left", "right", "inner", "outer", etc., indicating directions or positional relationships, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. The term "connection" only indicates the connection between devices and has no special meaning.
[0016] The present invention elaborates on a dispersant and its recycling method for waste solid electrolyte slurries from the following three embodiments. In the following three embodiments, the solid electrolyte slurry contains nanowires / nanotubes, inorganic oxide solid electrolytes, and a solvent. The inorganic oxide solid electrolyte is selected from at least one of LiSICON, NASICON, perovskite, garnet, inverse perovskite, lithium aluminum phosphate LiSICON-type electrolyte, Li1-x1Ti1-x1M1x1OPO4, Li1+x2H1-x2Al(PO4)O1-yM2y, LilPO4Fx3(OH)1-x3, and Na-β / β″-Al 2 O 3 and at least one of the following, where M1 is selected from at least one of Nb, Ta, and Sb, M2 is selected from at least one of F, Cl, Br, and I, 0 ≤ x1 ≤ 0.7, 0 ≤ x2 < 1, 0 ≤ x3 < 1, and 0 < y < 0.1. The nanowires / nanotubes are selected from one or more of CNT, titanium oxide nanowires, and aluminum oxide nanowires. The solvent contains at least one of water, NMP, ethanol, N,N-dimethylformamide, dimethylacetamide, 1,3-dioxolane, and dimethyl carbonate. The laser particle size D50 of the solid electrolyte particles in the solid electrolyte slurry is 100 nm to 500 nm. The solid content range of the solid electrolyte slurry is 1% to 99%.
[0017] Example 1: A dispersant for recycling waste solid electrolyte slurries. The dispersant is polyvinylpyrrolidone, and the addition amount of the dispersant accounts for 5% of the volume content of the electrolyte powder in the solid electrolyte slurry.
[0018] When using this dispersant to recycle the solid electrolyte slurry, first add the dispersant to the waste solid electrolyte slurry. Then mix and stir the solid electrolyte and the dispersant, and then let it stand or centrifuge, controlling the process temperature at 30°C. Finally, separate and discard the supernatant after standing, and dry and then calcine the precipitate separation obtained after standing at a low temperature. The calcination temperature is 300°C, and a solid electrolyte powder is obtained after calcination.
[0019] Example 2: A dispersant for recycling waste solid electrolyte slurries. The dispersant is polyacrylic acid, and the addition amount of the dispersant accounts for 5% of the volume content of the electrolyte powder in the solid electrolyte slurry.
[0020] When using this dispersant to recycle the solid electrolyte slurry, first add the dispersant to the waste solid electrolyte slurry. Then mix and stir the solid electrolyte and the dispersant, and then let it stand or centrifuge, controlling the process temperature at 30°C. Finally, separate and discard the supernatant after standing, and dry and then calcine the precipitate separation obtained after standing at a low temperature. The calcination temperature is 300°C, and a solid electrolyte powder is obtained after calcination.
[0021] Example 3: A dispersant for recovering waste solid electrolyte slurry, wherein the dispersant is polymaleic acid, and the amount of the dispersant added accounts for 5% of the volume content of the electrolyte powder in the solid electrolyte slurry.
[0022] When the dispersant is used to recycle the solid electrolyte slurry, the dispersant is first added to the waste solid electrolyte slurry. The solid electrolyte and the dispersant are then mixed and stirred, and then allowed to stand or centrifuge, and the process temperature is controlled at 30°C. Finally, the supernatant after standing is separated and scrapped, and the precipitated separation after standing is dried and calcined at low temperature, with the calcination temperature at 300°C, to obtain solid electrolyte powder.
[0023] The present invention adopts two control groups to compare with three embodiments, and the specific comparison parameters are shown in Tables 1 and 2:
[0024] Table 1 Raw material parameters and processing technology description
[0025]
[0026]
[0027] Table 2 Comparison of sedimentation parameters
[0028]
[0029] As can be seen from the above, when the dispersant of the present invention is polyvinyl pyrrolidone, its sedimentation amount and the purity of the material after calcination are optimal. During specific operation, different types of solid electrolyte slurries can be recycled. The recycling process is simple, and only the dispersant needs to be added, and then centrifuged or left to stand. The recycled material can be calcined to remove additive impurities to obtain a solid electrolyte powder that can be reused. The use of high molecular weight polyvinyl pyrrolidone can play a role in adsorbing electrolyte particles, and after capturing the electrolyte particles, the macromolecular dispersant will also self-crosslink, and quickly settle under the action of gravity, significantly improving the recovery efficiency, and the high molecular weight polyvinyl pyrrolidone can be completely removed during the later drying and calcining process. The polymer anion dispersant has an anchoring group and can also adsorb solid electrolyte particles. Under the action of gravity, the force of the system is gradually uneven, and the long polymer chain cannot remain stable, thereby increasing the sedimentation rate of the slurry, which can improve the recovery efficiency, and the polymer anion dispersant can also be completely removed after drying and calcining in the later stage.
[0030] Example 4: A dispersant for recovering waste solid electrolyte slurry, wherein the dispersant is polymaleic acid, and the amount of the dispersant added accounts for 1% of the volume content of the electrolyte powder in the solid electrolyte slurry.
[0031] When the dispersant is used to recycle the solid electrolyte slurry, the dispersant is first added to the waste solid electrolyte slurry. The solid electrolyte and the dispersant are then mixed and stirred, and then allowed to stand or centrifuge, and the process temperature is controlled at 20°C. Finally, the supernatant after standing is separated and scrapped, and the precipitated separation after standing is dried and calcined at low temperature, with the calcination temperature of 300°C, to obtain solid electrolyte powder.
[0032] Example 5: A dispersant for recovering waste solid electrolyte slurry, wherein the dispersant is polymaleic acid, and the amount of the dispersant added accounts for 10% of the volume content of the electrolyte powder in the solid electrolyte slurry.
[0033] When the dispersant is used to recycle the solid electrolyte slurry, the dispersant is first added to the waste solid electrolyte slurry. The solid electrolyte and the dispersant are then mixed and stirred, and then allowed to stand or centrifuge, and the process temperature is controlled at 40°C. Finally, the supernatant after standing is separated and scrapped, and the precipitated separation after standing is dried and calcined at low temperature, with a calcination temperature of 500°C, to obtain a solid electrolyte powder.
[0034] Example 6: A dispersant for recovering waste solid electrolyte slurry, wherein the dispersant is polymaleic acid, and the amount of the dispersant added accounts for 1% of the volume content of the electrolyte powder in the solid electrolyte slurry.
[0035] When the dispersant is used to recycle the solid electrolyte slurry, the dispersant is first added to the waste solid electrolyte slurry. The solid electrolyte and the dispersant are then mixed and stirred, and then allowed to stand or centrifuge, and the process temperature is controlled at 40°C. Finally, the supernatant after standing is separated and scrapped, and the precipitated separation after standing is dried and calcined at low temperature, with the calcination temperature at 300°C, to obtain a solid electrolyte powder.
[0036] Example 7: A dispersant for recovering waste solid electrolyte slurry, wherein the dispersant is polymaleic acid, and the amount of the dispersant added accounts for 10% of the volume content of the electrolyte powder in the solid electrolyte slurry.
[0037] When the dispersant is used to recycle the solid electrolyte slurry, the dispersant is first added to the waste solid electrolyte slurry. The solid electrolyte and the dispersant are then mixed and stirred, and then allowed to stand or centrifuge, and the process temperature is controlled at 20°C. Finally, the supernatant after standing is separated and scrapped, and the precipitated separation after standing is dried and calcined at low temperature, with the calcination temperature of 300°C, to obtain solid electrolyte powder.
[0038] Example 8: A dispersant for recovering waste solid electrolyte slurry, wherein the dispersant is polymaleic acid, and the amount of the dispersant added accounts for 10% of the volume content of the electrolyte powder in the solid electrolyte slurry.
[0039] When the dispersant is used to recycle the solid electrolyte slurry, the dispersant is first added to the waste solid electrolyte slurry. The solid electrolyte and the dispersant are then mixed and stirred, and then allowed to stand or centrifuge, and the process temperature is controlled at 20°C. Finally, the supernatant after standing is separated and scrapped, and the precipitated separation after standing is dried and calcined at low temperature, with a calcination temperature of 500°C, to obtain a solid electrolyte powder.
[0040] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A waste solid electrolyte slurry recovery dispersant, characterized in that: The dispersant comprises one or more of polyvinyl pyrrolidone, polymaleic acid and polyacrylic acid.
2. The waste solid electrolyte slurry recovery dispersant according to claim 1, characterized in that: The added amount of the dispersant accounts for 1% to 10% of the volume content of the electrolyte powder in the solid electrolyte slurry.
3. A method for recovering solid electrolyte slurry using the waste solid electrolyte slurry recovery dispersant according to claim 1, characterized in that: The method comprises the following steps: S1. adding a dispersant to the waste solid electrolyte slurry; S2, mixing and stirring the solid electrolyte and the dispersant, and then standing or centrifuging, and controlling the process temperature at 20°C to 40°C; S3, separating and discarding the supernatant after standing, drying the precipitate after standing, and calcining at low temperature, the calcination temperature is 300° C. to 500° C., and obtaining solid electrolyte powder after calcination.