Sodium ion battery positive electrode slurry and preparation method thereof, sodium ion battery positive electrode, sodium ion battery and power equipment
By using SEBS rubber and silica in the sodium-ion battery positive electrode slurry to form a three-dimensional network structure, the gel problem of the sodium-ion battery positive electrode material was solved, and the battery internal resistance was reduced and the cycle performance was improved.
Patent Information
- Application Number
- CN202310098725.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-02-10
- Publication Date
- 2025-09-05
- Estimated Expiration
- 2043-02-10
AI Technical Summary
During the production process, the positive electrode material of sodium ion batteries has a high alkalinity, which leads to serious gelation, affecting uniform stirring and coating. Existing additives cannot effectively solve the gel problem, resulting in high internal resistance of the battery and poor cycle.
SEBS rubber is used as a binder, and materials containing silicon-oxygen bonds such as silicon dioxide are added to form a three-dimensional network structure, improve the stability and viscosity of the slurry, and enhance battery performance.
Significantly reduce the internal resistance of the battery, improve the cycle performance and high-temperature storage performance, while improving the stability and electrochemical performance of the slurry.
Smart Images
Figure BDA0004072597970000121 
Figure BDA0004072597970000131
Abstract
Description
Technical Field
[0001] The present application relates to the field of sodium ion batteries, and in particular to a sodium ion battery positive electrode slurry and a preparation method thereof, a sodium ion battery positive electrode, a sodium ion battery and power equipment. Background Art
[0002] Because sodium-ion cathode materials primarily use sodium carbonate as a sodium source during production, they are highly alkaline. Currently, common cathode slurry systems primarily utilize polyvinylidene fluoride (PVDF). While PVDF offers strong bonding strength and electrochemical stability, it suffers from poor alkali resistance. PVDF undergoes an elimination reaction in the presence of alkaline sodium ion materials to produce water, and PVDF is a non-aqueous solvent. The double bonds generated by the elimination reaction cause cross-linking reactions between PVDF molecular chains, forming a gel.
[0003] Sodium ion materials react more easily with CO2 and H2O in the air, forming NaOH and Na2CO3 on the surface of the material. Residual alkaline content and pH testing of finished sodium ion positive electrode materials revealed that the residual NaOH content in the sodium ion material was 2.37%, the Na2CO3 content was 2.10%, and the pH was 13.1. Lithium ion positive electrode materials, on the other hand, generally use lithium carbonate as a lithium source during production, and their residual LiOH and Li2CO3 content is generally less than 0.1%, with a pH of 8-11. In comparison, the alkalinity of sodium ion materials is significantly stronger than that of lithium ion materials, so the gelation phenomenon that occurs during the homogenization process is more severe. Current additives used to alleviate the coagulation of lithium ion slurries do not achieve a good anti-coagulation effect when used in sodium ion slurries.
[0004] The gelation phenomenon that occurs during the homogenization process will cause the sodium ion positive electrode material to be unable to be evenly stirred, and a large number of particles will agglomerate. At the same time, the slurry in the gel state cannot be coated normally, which brings many inconveniences to the production of sodium ion batteries.
[0005] In order to solve the above problems, invention 202211468770X provides a sodium ion battery positive electrode material, a positive electrode sheet and a preparation method, using SEBS rubber as an adhesive to form a blended material, which can have the chemical stability of SEBS rubber itself, and at the same time utilize the stability of solvent oil when preparing the slurry, and has alkali resistance and antioxidant ability. Therefore, the sodium ion positive electrode material, when prepared with SEBS rubber binder, has the advantages of good fluidity, good stability, and small viscosity change.
[0006] However, the batteries prepared using this method have a high internal resistance of approximately 150-200 milliohms, severe polarization, and poor cycling. This is because in a solvent oil system, slurry stability can only be guaranteed when a sufficient amount of SEBS is added. SEBS is insulating, resulting in high internal resistance and poor cycling. Summary of the Invention
[0007] The purpose of this application is to provide a sodium ion battery positive electrode slurry and a preparation method thereof, a sodium ion battery positive electrode, a sodium ion battery and an electric power device to solve the above problems.
[0008] To achieve the above objectives, this application adopts the following technical solutions:
[0009] A sodium ion battery positive electrode slurry, comprising a positive electrode active material, a conductive agent, a binder and a solvent, and also comprising an additive;
[0010] The adhesive is SEBS rubber, the solvent includes solvent oil, and the additive includes a material containing a silicon-oxygen bond.
[0011] Preferably, the grade of the SEBS rubber is 1924 or 1701;
[0012] Preferably, the SEBS rubber accounts for 1%-3% of the total mass of the sodium ion battery positive electrode slurry.
[0013] Preferably, the conductive agent is conductive carbon black and carbon nanotubes;
[0014] Preferably, the conductive carbon black accounts for 0.5-2% of the total mass of the sodium ion battery positive electrode slurry, and the carbon nanotubes account for 0.5-2% of the total mass of the sodium ion battery positive electrode slurry.
[0015] Preferably, the solvent oil is dearomatized solvent oil;
[0016] Preferably, the flash point of the dearomatized solvent oil is 80-120°C;
[0017] Preferably, the brand of the dearomatized solvent oil is D85 or D80, accounting for 25-45% of the total mass of the sodium ion battery positive electrode slurry.
[0018] Preferably, the material containing silicon-oxygen bonds includes one or more of silicon dioxide, diatomaceous earth, siloxane, silicone oil and kaolin;
[0019] Preferably, the silicon dioxide is hydrophobic nano-silica;
[0020] Preferably, the silicon dioxide accounts for 0.1%-1.0% of the total mass of the sodium ion battery positive electrode slurry.
[0021] Preferably, the positive electrode active material comprises one of a layered oxide, a phosphate compound and a Prussian compound;
[0022] Preferably, the positive electrode active material includes one or more of sodium nickel iron manganate layered oxide, sodium vanadium fluorophosphate and sodium vanadium phosphate.
[0023] The present application also provides a method for preparing the sodium ion battery positive electrode slurry, comprising:
[0024] The positive electrode active material, the conductive agent, the binder, the solvent, and the additives are mixed.
[0025] Preferably, the mixing comprises:
[0026] First, the binder is added to a portion of the solvent and ball-milled to obtain a first mixture, and then the conductive agent is added to the first mixture to obtain a second mixture; and the positive electrode active material is added to the second mixture to obtain a third mixture;
[0027] Using the remaining solvent to adjust the solid content of the slurry to obtain the sodium ion battery positive electrode slurry;
[0028] Preferably, the solid content of the sodium ion battery positive electrode slurry is 55%-75%.
[0029] The present application also provides a sodium ion battery positive electrode, the raw materials of which include the sodium ion battery positive electrode slurry.
[0030] The present application also provides a sodium ion battery, comprising the sodium ion battery positive electrode.
[0031] The present application also provides an electric power device, comprising the sodium ion battery.
[0032] Compared with the prior art, the advantages of this application include:
[0033] The sodium ion battery positive electrode slurry provided by the present application uses a material containing a silicon-oxygen bond as an additive. The silicon hydroxyl group can directly or indirectly generate hydrogen bonding through itself or liquid molecules, creating a temporary three-dimensional space; the hydrogen bonding connects the additive aggregates dispersed in the system to form a complete additive network that fills the entire system, thereby increasing the viscosity of the system and thus having a thickening effect; the silicon hydroxyl group can form a physical or chemical bond with the rubber macromolecule, forming an adsorption layer of rubber molecules on the surface of the additive, forming a three-dimensional network structure in which the additive particles and the rubber molecules are integrated, effectively limiting the deformation of the rubber molecular chain, thereby achieving a reinforcement effect. The physical properties of the reinforced rubber are greatly improved, and its tensile strength and tear strength will be greatly improved.
[0034] By adding materials containing silicon-oxygen bonds to the slurry, the slurry's stability can be improved by leveraging their superior stability and thickening properties. Silicon-oxygen bond-containing materials are also commonly used as reinforcing agents for rubber. The addition of these materials not only enhances strength and toughness, but also significantly improves water resistance and aging resistance. The resulting battery exhibits significantly reduced internal resistance, significantly improved cycle life, and excellent high-temperature storage performance.
[0035] The method for preparing the positive electrode slurry for sodium ion batteries provided in this application is simple to operate.
[0036] The sodium ion battery positive electrode, sodium ion battery and power equipment provided in this application have excellent electrical performance. DETAILED DESCRIPTION
[0037] As used herein:
[0038] "Prepared from" is synonymous with "comprising." As used herein, the terms "comprising," "including," "having," "containing," or any other variations thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises the listed elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.
[0039] The conjunction "consisting of" excludes any unspecified element, step, or component. If used in a claim, this phrase renders the claim closed, excluding materials other than those described, except for conventional impurities associated therewith. When the phrase "consisting of" appears in a clause of the body of a claim, rather than immediately following the subject matter, it limits only the elements described in that clause; other elements are not excluded from the claim as a whole.
[0040] When an amount, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper preferred values and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pairing of any range upper limit or preferred value with any range lower limit or preferred value, regardless of whether the range is disclosed alone. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted as including the range "1 to 4", "1 to 3", "1 to 2", "1 to 2 and 4 to 5", "1 to 3 and 5", etc. When a numerical range is described herein, unless otherwise stated, the range is intended to include its end values and all integers and fractions within the range.
[0041] In these examples, parts and percentages are by mass unless otherwise indicated.
[0042] "Parts by mass" refers to the basic unit of measurement used to express the mass ratio of multiple components. One part can represent any unit of mass, such as 1g or 2.689g. If we say that the mass of component A is a parts and the mass of component B is b parts, this means the ratio of the mass of component A to the mass of component B is a:b. Alternatively, we could say that the mass of component A is aK and the mass of component B is bK (K is an arbitrary number representing a multiplication factor). It's important to note that, unlike parts by mass, the sum of the mass of all components is not limited to 100 parts.
[0043] "And / or" is used to indicate that one or both of the stated situations may occur, for example, A and / or B includes (A and B) and (A or B).
[0044] A sodium ion battery positive electrode slurry, comprising a positive electrode active material, a conductive agent, a binder and a solvent, and also comprising an additive;
[0045] The adhesive is SEBS rubber, the solvent includes solvent oil, and the additive includes a material containing a silicon-oxygen bond.
[0046] In an optional embodiment, the grade of the SEBS rubber is 1924 or 1701;
[0047] In an optional embodiment, the SEBS rubber accounts for 1%-3% of the total mass of the sodium ion battery positive electrode slurry.
[0048] Optionally, the proportion of the SEBS rubber to the total mass of the sodium ion battery positive electrode slurry may be 1%, 1.5%, 2%, 2.5%, 3% or any value between 1% and 3%.
[0049] In an optional embodiment, the conductive agent is conductive carbon black and carbon nanotubes;
[0050] In an optional embodiment, the conductive carbon black accounts for 0.5-2% of the total mass of the sodium ion battery positive electrode slurry, and the carbon nanotubes account for 0.5-2% of the total mass of the sodium ion battery positive electrode slurry.
[0051] Optionally, the proportion of the conductive carbon black to the total mass of the sodium ion battery positive electrode slurry can be 0.5%, 1%, 1.5%, 2% or any value between 0.5-2%, and the proportion of the carbon nanotubes to the total mass of the sodium ion battery positive electrode slurry can be 0.5%, 1%, 1.5%, 2% or any value between 0.5-2%.
[0052] In an optional embodiment, the solvent oil is dearomatized solvent oil;
[0053] In an optional embodiment, the flash point of the dearomatized solvent oil is 80-120°C;
[0054] Optionally, the flash point of the dearomatized solvent oil may be 80°C, 90°C, 100°C, 110°C, 120°C or any value between 80-120°C;
[0055] In an optional embodiment, the dearomatized solvent oil is of the brand D85 or D80, accounting for 25-45% of the total mass of the sodium ion battery positive electrode slurry.
[0056] Optionally, the proportion of the dearomatized solvent oil to the total mass of the sodium ion battery positive electrode slurry can be 25%, 30%, 35%, 40%, 45% or any value between 25-45%.
[0057] In an optional embodiment, the material containing silicon-oxygen bonds includes one or more of silicon dioxide, diatomaceous earth, siloxane, silicone oil and kaolin;
[0058] In an optional embodiment, the silicon dioxide is hydrophobic nano-silica;
[0059] In an optional embodiment, the silicon dioxide accounts for 0.1%-1.0% of the total mass of the sodium ion battery positive electrode slurry.
[0060] Optionally, the proportion of the silicon dioxide to the total mass of the sodium ion battery positive electrode slurry can be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0% or any value between 0.1% and 1.0%.
[0061] Adding a certain proportion of nano-silica to batteries can significantly improve their electrochemical performance, such as mechanical properties, conductivity, elongation at break, cycle performance, and lifespan. Furthermore, nano-silica particles can absorb moisture from liquid electrolytes, reducing interfacial reactions. Therefore, nano-silica has high application value in the battery field. This solution reduces the amount of SEBS added by one-third while ensuring slurry stability. Simultaneously, the addition of silica thickens the slurry, improving its stability and significantly enhancing the battery's electrochemical performance. The resulting battery has a significantly reduced internal resistance to approximately 37-40 milliohms, significantly improved cycle performance, and excellent high-temperature storage performance.
[0062] By adding silica to the slurry, the slurry's stability can be improved by leveraging its superior stability and thickening properties. Silica is also commonly used as a reinforcing agent for rubber. The addition of silica not only improves its strength and toughness, but also significantly enhances its water resistance and aging resistance. The resulting battery exhibits significantly reduced internal resistance, significantly improved cycle life, and excellent high-temperature storage performance.
[0063] When silica is dispersed and mixed with a low-polarity solvent, the silanol groups on the surface can directly or indirectly form hydrogen bonds with themselves or with liquid molecules, creating a temporary three-dimensional space. Hydrogen bonding connects the silica aggregates dispersed in the system to form a complete silica network that fills the entire system, increasing the viscosity of the system and thus achieving thickening properties.
[0064] The silanol groups on the surface of silica can form physical or chemical bonds with rubber macromolecules, forming an adsorption layer of rubber molecules on the surface of silica, and forming a three-dimensional network structure integrating silica particles and rubber analysis, effectively limiting the deformation of rubber molecular chains, thereby achieving a reinforcement effect. The physical properties of the reinforced rubber are greatly improved, and its tensile strength and tear strength will be greatly improved.
[0065] Optionally, the proportion of the silicon dioxide to the total mass of the sodium ion battery positive electrode slurry can be 0.1%, 0.2%, 0.3%, 0.4%, 0.5% or any value between 0.1% and 0.5%.
[0066] In an optional embodiment, the positive electrode active material includes one of a layered oxide, a phosphate compound, and a Prussian compound;
[0067] In an optional embodiment, the positive electrode active material includes one or more of sodium nickel iron manganate layered oxide, sodium vanadium fluorophosphate and sodium vanadium phosphate.
[0068] The present application also provides a method for preparing the sodium ion battery positive electrode slurry, comprising:
[0069] The positive electrode active material, the conductive agent, the binder, the solvent, and the additives are mixed.
[0070] In an optional embodiment, the mixing comprises:
[0071] First, the binder is added to a portion of the solvent and ball-milled to obtain a first mixture, and then the conductive agent is added to the first mixture to obtain a second mixture; and the positive electrode active material is added to the second mixture to obtain a third mixture;
[0072] Using the remaining solvent to adjust the solid content of the slurry to obtain the sodium ion battery positive electrode slurry;
[0073] In an optional embodiment, the solvent is used to adjust the solid content of the slurry to 55%-75%.
[0074] Optionally, the solid content of the sodium ion battery positive electrode slurry can be 55%, 60%, 65%, 70%, 75% or any value between 55% and 75%.
[0075] The present application also provides a sodium ion battery positive electrode, the raw materials of which include the sodium ion battery positive electrode slurry.
[0076] The present application also provides a sodium ion battery, comprising the sodium ion battery positive electrode.
[0077] The present application also provides an electric power device, comprising the sodium ion battery.
[0078] The embodiments of the present application will be described in detail below in conjunction with specific examples, but it will be understood by those skilled in the art that the following examples are merely illustrative of the present application and should not be considered as limiting the scope of the present application. In the examples, if specific conditions are not specified, the conditions are carried out according to conventional conditions or manufacturer recommendations. The reagents or instruments used are not specified by the manufacturer and are conventional products that can be purchased commercially.
[0079] Example 1
[0080] This embodiment provides a sodium ion battery positive electrode slurry, and the preparation method thereof is as follows:
[0081] (1) 9 g SEBS (brand 1924) + 7.5 g CNTs were added to 283.5 g solvent oil (brand: D85) and dissolved by ball milling and then mixed uniformly to prepare the first mixture;
[0082] (2) adding 7.5 g of conductive carbon black and 1.5 g of nano-silicon dioxide to the first mixture, stirring and dispersing the mixture uniformly to obtain a second mixture;
[0083] (3) taking 474.5 g of sodium nickel iron manganate, adding it to the second mixture, stirring and dispersing the mixture to obtain a third mixture;
[0084] (4) Solvent oil is added to adjust the solid content of the slurry to 60%, thereby obtaining a positive electrode slurry for a sodium ion battery.
[0085] Example 2
[0086] This embodiment provides a sodium ion battery positive electrode slurry, and the preparation method thereof is as follows:
[0087] (1) 9 g SEBS (brand 1924) + 7.5 g CNTs were added to 283.5 g solvent oil (brand: D85) and dissolved by ball milling and then mixed uniformly to prepare the first mixture;
[0088] (2) adding 7.5 g of conductive carbon black and 1.0 g of nano-silicon dioxide to the first mixture, stirring and dispersing the mixture uniformly to obtain a second mixture;
[0089] (3) taking 475 g of sodium nickel iron manganate, adding it to the second mixture, stirring and dispersing the mixture to obtain a third mixture;
[0090] (4) Solvent oil is added to adjust the solid content of the slurry to 60%, thereby obtaining the sodium ion battery positive electrode slurry.
[0091] Example 3
[0092] This embodiment provides a sodium ion battery positive electrode slurry, and the preparation method thereof is as follows:
[0093] (1) 7.5 g of SEBS (brand 1924) + 7.5 g of CNTs were added to 283.5 g of solvent oil (brand: D85), ball milled and dissolved, and then mixed uniformly to prepare a first mixture;
[0094] (2) adding 7.5 g of conductive carbon black and 1.5 g of nano-silicon dioxide to the first mixture, stirring and dispersing the mixture uniformly to obtain a second mixture;
[0095] (3) taking 476 g of sodium nickel iron manganate, adding it to the second mixture, stirring and dispersing the mixture to obtain a third mixture;
[0096] (4) Solvent oil is added to adjust the solid content of the slurry to 60%, thereby obtaining the sodium ion battery positive electrode slurry.
[0097] Example 4
[0098] This embodiment provides a sodium ion battery positive electrode slurry, and the preparation method thereof is as follows:
[0099] (1) 9 g SEBS (brand 1924) + 5 g CNTs were added to 283.5 g solvent oil (brand: D85) and dissolved by ball milling and then mixed uniformly to prepare the first mixture;
[0100] (2) adding 5 g of conductive carbon black and 1.5 g of nano-silicon dioxide to the first mixture, stirring and dispersing the mixture uniformly to obtain a second mixture;
[0101] (3) taking 479.5 g of sodium nickel iron manganate, adding it to the second mixture, stirring and dispersing the mixture to obtain a third mixture;
[0102] (4) Solvent oil is added to adjust the solid content of the slurry to 60%, thereby obtaining the sodium ion battery positive electrode slurry.
[0103] Example 5
[0104] This embodiment provides a sodium ion battery positive electrode slurry, and the preparation method thereof is as follows:
[0105] (1) 9 g SEBS (brand 1924) + 7.5 g CNTs were added to 283.5 g solvent oil (brand: D85) and dissolved by ball milling and then mixed uniformly to prepare the first mixture;
[0106] (2) adding 7.5 g of conductive carbon black and 2.5 g of nano-silicon dioxide to the first mixture, stirring and dispersing the mixture uniformly to obtain a second mixture;
[0107] (3) taking 473.5 g of sodium nickel iron manganate, adding it to the second mixture, stirring and dispersing the mixture to obtain a third mixture;
[0108] (4) Solvent oil is added to adjust the solid content of the slurry to 60%, thereby obtaining the sodium ion battery positive electrode slurry.
[0109] Example 6
[0110] This embodiment provides a sodium ion battery positive electrode slurry, and the preparation method thereof is as follows:
[0111] (1) 5 g SEBS (brand 1924) + 2.5 g SEBS (brand 1701) + 7.5 g CNTs were added to 283.5 g solvent oil (brand: D85) and dissolved by ball milling and then mixed uniformly to prepare the first mixture;
[0112] (2) adding 7.5 g of conductive carbon black and 1.5 g of nano-silicon dioxide to the first mixture, stirring and dispersing the mixture uniformly to obtain a second mixture;
[0113] (3) taking 474.5 g of sodium nickel iron manganate, adding it to the second mixture, stirring and dispersing the mixture to obtain a third mixture;
[0114] (4) Solvent oil is added to adjust the solid content of the slurry to 60%, thereby obtaining a positive electrode slurry for a sodium ion battery.
[0115] Comparative Example 1
[0116] This comparative example provides a sodium ion battery positive electrode slurry, and the preparation method thereof is as follows:
[0117] (1) 9 g of SEBS (brand 1924) and 7.5 g of CNTs were added to 283.5 g of solvent oil (brand: D85), dissolved by ball milling, and then mixed uniformly to prepare a first mixture;
[0118] (2) adding 7.5 g of conductive carbon black to the first mixture and stirring to disperse the mixture uniformly to obtain a second mixture;
[0119] (3) taking 476 g of sodium nickel iron manganate, adding it to the second mixture, stirring and dispersing the mixture to obtain a third mixture;
[0120] (4) Solvent oil is added to adjust the solid content of the slurry to 60%, thereby obtaining the sodium ion battery positive electrode slurry.
[0121] Comparative Example 2
[0122] This comparative example provides a sodium ion battery positive electrode slurry, and the preparation method thereof is as follows:
[0123] (1) 9 g of SEBS (brand 1924) was added to 283.5 g of solvent oil (brand: D85) and dissolved by ball milling and then mixed uniformly to prepare a first mixture;
[0124] (2) adding 15 g of conductive carbon black to the first mixture and stirring to disperse the mixture uniformly to obtain a second mixture;
[0125] (3) taking 476 g of sodium nickel iron manganate, adding it to the second mixture, stirring and dispersing the mixture to obtain a third mixture;
[0126] (4) Solvent oil is added to adjust the solid content of the slurry to 60%, thereby obtaining the sodium ion battery positive electrode slurry.
[0127] The obtained positive electrode slurry is coated on a metal aluminum foil, baked and dried, and then rolled and slit to obtain a positive electrode sheet.
[0128] The peel strength is measured according to the 180° peel force test standard. The positive electrode sheet is cut into a rectangle with a length of 100mm and a width of 24mm. A 50mm wide stainless steel plate is affixed with double-sided tape (10mm long and 24mm wide). The cut positive electrode sheet is then affixed to the double-sided tape on the stainless steel plate. A 2kg roller is then rolled back and forth on the surface of the positive electrode sheet three times. The sample is fixed to the testing machine, with the axis of the electrode sheet aligned with the direction of the applied force. The testing machine is loaded at a peel speed of 100mm / min until the positive electrode sheet is completely peeled. The test is then stopped and the average peel force is recorded as F (unit: N).
[0129] The positive electrode sheets prepared in the examples and comparative examples were used, and the negative electrode was hard carbon. After being assembled into batteries, they were tested using the Xinwei battery testing system. The test voltage of the examples and comparative examples was 2.0-4.0V, and the test temperature was 25°C. The test results are shown in Table 1 below.
[0130] Table 1 Test results
[0131]
[0132]
[0133] As shown in Table 1 above, by adding silicon dioxide to the slurry, the peeling force of the electrode is significantly improved, the internal resistance of the prepared battery is significantly reduced, the cycle is significantly improved, and the high-temperature storage performance at 60 degrees is good.
[0134] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.
[0135] Furthermore, those skilled in the art will appreciate that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of this application and to form distinct embodiments. For example, in the claims above, any of the claimed embodiments may be used in any combination. The information disclosed in this background section is intended solely to enhance understanding of the overall background of this application and should not be construed as an admission or any implication that such information constitutes prior art known to those skilled in the art.
Claims
1. A sodium ion battery positive electrode slurry, comprising a positive electrode active material, a conductive agent, a binder and a solvent, characterized in that: Also includes additives; The binder is SEBS rubber, the solvent includes solvent oil, and the additive includes a material containing a silicon-oxygen bond; the SEBS rubber accounts for 1%-3% of the total mass of the sodium ion battery positive electrode slurry; The conductive agent is conductive carbon black and carbon nanotubes; The conductive carbon black accounts for 0.5-2% of the total mass of the sodium ion battery positive electrode slurry, and the carbon nanotubes account for 0.5-2% of the total mass of the sodium ion battery positive electrode slurry; The solvent oil is dearomatized solvent oil; The brand of the dearomatized solvent oil is D85 or D80, accounting for 25-45% of the total mass of the sodium ion battery positive electrode slurry; The material containing silicon-oxygen bonds includes silicon dioxide; the silicon dioxide accounts for 0.1%-1.0% of the total mass of the sodium ion battery positive electrode slurry; The positive electrode active material includes one or more of sodium nickel iron manganate layered oxide, sodium vanadium fluorophosphate and sodium vanadium phosphate.
2. The sodium ion battery positive electrode slurry according to claim 1, characterized in that The flash point of the dearomatized solvent oil is 80-120°C.
3. The positive electrode slurry for sodium ion batteries according to claim 1, characterized in that The silicon dioxide is hydrophobic nano silicon dioxide.
4. A method for preparing a positive electrode slurry for a sodium ion battery according to any one of claims 1 to 3, characterized in that: include: The positive electrode active material, the conductive agent, the binder, the solvent, and the additives are mixed.
5. The method for preparing a positive electrode slurry for a sodium ion battery according to claim 4, wherein: The mixing includes: First, the binder is added to a portion of the solvent and ball-milled to obtain a first mixture, and then the conductive agent is added to the first mixture to obtain a second mixture; and the positive electrode active material is added to the second mixture to obtain a third mixture; The remaining solvent is used to adjust the solid content of the slurry to obtain the sodium ion battery positive electrode slurry.
6. The method for preparing a positive electrode slurry for a sodium ion battery according to claim 4, wherein: The solid content of the sodium ion battery positive electrode slurry is 55%-75%.
7. A sodium ion battery positive electrode, characterized in that The raw materials include the sodium ion battery positive electrode slurry according to any one of claims 1 to 3.
8. A sodium ion battery, characterized in that: Including the sodium ion battery positive electrode according to claim 7.
9. An electric power device, characterized in that: Including the sodium ion battery according to claim 8.
Citation Information
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