Sodium-ion battery positive electrode slurry and preparation method thereof, positive electrode plate, sodium-ion battery and power-related equipment

Abstract

The invention provides sodium-ion battery positive electrode slurry and a preparation method thereof, a positive electrode plate, a sodium-ion battery and power-related equipment, and relates to the technical field of sodium-ion battery positive electrode slurry. The sodium-ion battery positive electrode slurry comprises the following raw materials: a sodium-ion battery positive electrode material, a conductive agent, a binder, a weak acid additive, a dehydrating agent and a solvent, the weak acid additive comprises one or more of malic acid, oxalic acid, boric acid, phosphoric acid, citric acid and sorbic acid; the dehydrating agent comprises one or more of polyacrylamide, anhydrous calcium chloride and potassium chloride. The slurry is prevented from forming gel through the synergistic effect of the weak acid additive and the dehydrating agent, the weak acid additive and residual alkali on the surface of the sodium-ion battery positive electrode material are subjected to chemical reaction to generate water, the residual alkali is prevented from attacking a binder, and formation of the gel is reduced; and the dehydrating agent is used for removing water, so that the flowability of the slurry is not influenced.

Description

Technical Field

[0001] The present application relates to the technical field of positive electrode slurry for sodium ion batteries, and in particular to a positive electrode slurry for sodium ion batteries and a preparation method thereof, a positive electrode sheet, a sodium ion battery and electrical equipment. Background Art

[0002] In the composition of sodium-ion batteries, the positive electrode material occupies the most important position. The performance of the positive electrode material will directly determine the performance indicators of the final sodium-ion battery product. However, the air stability of the positive electrode material is poor. When the material is exposed to a humid atmosphere, it is easy to absorb H2O and Na2O from the atmosphere. + Ions easily react with H + Ion exchange generates residual alkali on its surface. During the preparation of slurry, the residual alkali will attack the binder, causing the slurry viscosity to increase or even form gel, which will bring certain difficulties to coating and seriously affect the coating processing performance of the material. In addition, the residual alkali may also dissolve into the electrolyte, which will have a negative impact on the overall charge and discharge performance, cycle performance or battery volume, as well as safety performance of the battery. Summary of the invention

[0003] The purpose of the present application is to provide a sodium ion battery positive electrode slurry and a preparation method thereof, a sodium ion battery positive electrode sheet and a sodium ion battery to solve the above problems.

[0004] To achieve the above objectives, the first aspect of the present application provides a sodium ion battery positive electrode slurry, the raw materials of which include: a sodium ion battery positive electrode material, a conductive agent, a binder, a weak acid additive, a dehydrating agent, and a solvent;

[0005] The weak acid additive includes one or more of malic acid, oxalic acid, boric acid, phosphoric acid, citric acid, and sorbic acid;

[0006] The dehydrating agent includes one or more of polyacrylamide, anhydrous calcium chloride and potassium chloride.

[0007] Optionally, the mass ratio of the sodium ion battery positive electrode material, the weak acid additive, the dehydrating agent, the conductive agent, the binder and the solvent is 8: (0.1-1): (0.01-0.1): (1-3): (1-3): (20-30).

[0008] Optionally, the sodium ion battery positive electrode slurry meets at least one of the following conditions:

[0009] A. The positive electrode material of the sodium ion battery includes one or more of transition metal oxides, Prussian blue compounds, polyanion compounds, and organic compounds;

[0010] B. The conductive agent includes one or more of carbon nanotubes, acetylene black, and graphite;

[0011] C. The binder includes one or more of polyvinylidene fluoride, polyacrylic acid, and styrene-butadiene rubber;

[0012] D. The solvent includes one or more of N-methylpyrrolidone, dimethyl sulfoxide, tetrahydrofuran, water, and ethanol.

[0013] The second aspect of the present application provides a method for preparing the positive electrode slurry of a sodium ion battery, comprising:

[0014] The raw materials are mixed to prepare a positive electrode slurry for a sodium ion battery.

[0015] Optionally, the method for preparing the positive electrode slurry for a sodium ion battery satisfies at least one of the following conditions:

[0016] A. The mixing time is 0.5h-8h, and the rotation speed is 50 rpm-300 rpm;

[0017] B. The mixing includes: first mixing the binder and the solvent to obtain glue solution A;

[0018] The glue solution, the conductive agent, the weak acid additive and the dehydrating agent are mixed for a second time to obtain glue solution B;

[0019] The gel solution B and the sodium ion battery positive electrode material are mixed for the third time.

[0020] Optionally, the method for preparing the sodium ion battery positive electrode material comprises:

[0021] The raw material of the sodium ion battery positive electrode material is heat-treated under an oxygen atmosphere to obtain the sodium ion battery positive electrode material.

[0022] Optionally, the heating rate of the heat treatment is 1°C / min-10°C / min, the sintering temperature is 500°C-950°C, and the time is 12h-20h.

[0023] A third aspect of the present application provides a positive electrode plate, comprising the sodium ion battery positive electrode slurry or the sodium ion battery positive electrode slurry prepared by the preparation method of the sodium ion battery positive electrode slurry.

[0024] A fourth aspect of the present application provides a sodium ion battery, comprising the above-mentioned positive electrode plate.

[0025] The fifth aspect of the present application provides an electrical device, including the sodium ion battery.

[0026] Compared with the prior art, the beneficial effects of this application include:

[0027] The sodium ion battery positive electrode slurry provided in the present application prevents the slurry from forming gel through the synergistic effect of a weak acid additive and a dehydrating agent. The weak acid additive chemically reacts with the residual alkali on the surface of the sodium ion battery positive electrode material to produce water, thereby preventing the residual alkali from attacking the binder and reducing the formation of gel; the dehydrating agent removes water, thereby ensuring that the fluidity of the slurry is not affected.

[0028] The method for preparing the positive electrode slurry for a sodium ion battery provided in the present application is simple to operate and can be used to improve the slurry coating process during large-scale production. The prepared positive electrode slurry for a lithium ion battery is evenly coated, smooth and flat, has no granular feel, and has good processing performance.

[0029] The positive electrode provided in this application has high capacity and good cycle performance.

[0030] The sodium ion battery provided in the present application has a long service life, is energy-saving and environmentally friendly, and has high safety.

[0031] The electrical equipment provided by the present application has a long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope of the present application.

[0033] Figure 1 This is a physical picture of the sodium ion battery positive electrode slurry prepared in Example 1 coated on the current collector;

[0034] Figure 2 This is a physical picture of the sodium ion battery positive electrode slurry prepared in Comparative Example 1 coated on the current collector. DETAILED DESCRIPTION

[0035] As used herein:

[0036] "Prepared from" is synonymous with "comprising." As used herein, the terms "comprising," "including," "having," "containing," or any other variation 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.

[0037] The conjunction "consisting of excludes any unspecified element, step, or component. If used in a claim, this phrase renders the claim closed-ended so that it does not include 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.

[0038] 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 separately. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted as including ranges "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 in this article, unless otherwise stated, the range is intended to include its end values ​​and all integers and fractions within the range.

[0039] In these examples, parts and percentages are by mass unless otherwise indicated.

[0040] "Parts by mass" refers to the basic unit of measurement for expressing the mass ratio of multiple components. 1 part can represent any unit 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, it means the ratio of the mass of component A to the mass of component B is a:b. Alternatively, it means that the mass of component A is aK and the mass of component B is bK (K is an arbitrary number, indicating a multiple factor). It should not be misunderstood that, unlike the mass parts, the sum of the mass of all components is not limited to 100 parts.

[0041] "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).

[0042] In a first aspect, the present application provides a sodium ion battery positive electrode slurry, the raw materials of which include: a sodium ion battery positive electrode material, a conductive agent, a binder, a weak acid additive, a dehydrating agent, and a solvent;

[0043] The weak acid additive includes one or more of malic acid, oxalic acid, boric acid, phosphoric acid, citric acid, and sorbic acid;

[0044] It should be noted that weak acid additives are compounds with weak acidity. Weak acidity will not have much impact on the overall acidity and alkalinity of the material. If the material is more alkaline, just increase the amount of weak acid. If the acidity is too strong, it may lead to a decrease in the capacity of the material, increase the risk of gel formation, and affect the electrochemical performance of the material.

[0045] The dehydrating agent includes one or more of polyacrylamide, anhydrous calcium chloride and potassium chloride.

[0046] It should be noted that the dehydrating agent is a compound with strong dehydrating ability, which is beneficial to remove trace water produced by chemical reactions. The stronger the dehydrating ability of the dehydrating agent, the less the amount of dehydrating agent used, which is beneficial to saving resources and reducing the risk of the dehydrating agent affecting material properties.

[0047] In some embodiments, the mass ratio of the sodium ion battery positive electrode material, the weak acid additive, the dehydrating agent, the conductive agent, the binder, and the solvent is 8: (0.1-1): (0.001-0.01): (1-3): (1-3): (20-30).

[0048] Optionally, the mass ratio of the positive electrode material of the sodium ion battery, the weak acid additive, the dehydrating agent, the conductive agent, the binder, and the solvent can be 8:0.1:0.001:1:1:20, 8:0.5:0.001:1:1:20, 8:1:0.001:1:1:20, 8:0.1:0.005:1:1:20, 8:0.1:0.01:1:1:20, 8:0.1:0.001:2:1:20, 8:0. 1:0.001:3:1:20, 8:0.1:0.001:1:2:20, 8:0.1:0.001:1:3:20, 8:0.1:0.001:1:1:25, 8:0.1:0.001:1:1:30, 8:1:0.01:3:3:30 or any value between 8:(0.1-1):(0.001-0.01):(1-3):(1-3):(20-30).

[0049] In some embodiments, the sodium ion battery positive electrode slurry meets at least one of the following conditions:

[0050] A. The positive electrode material of the sodium ion battery includes one or more of transition metal oxides, Prussian blue compounds, polyanion compounds, and organic compounds;

[0051] In some embodiments, the transition metal oxide includes a transition metal oxide having a layered structure or a tunnel structure;

[0052] In some embodiments, the Prussian blue-based compounds include sodium ferrocyanide and / or sodium manganese cyanide compounds;

[0053] In some embodiments, the polyanionic compound includes one or more of fluorinated phosphate compounds, pyrophosphate compounds, phosphate compounds, and sulfate compounds;

[0054] In some embodiments, the organic compound includes polycarbazole and / or polyaniline;

[0055] B. The conductive agent includes one or more of carbon nanotubes, acetylene black, and graphite;

[0056] C. The binder includes one or more of polyvinylidene fluoride, polyacrylic acid, and styrene-butadiene rubber;

[0057] D. The solvent includes one or more of N-methylpyrrolidone, dimethyl sulfoxide, tetrahydrofuran, water, and ethanol.

[0058] The second aspect of the present application provides a method for preparing the positive electrode slurry of a sodium ion battery, comprising:

[0059] The raw materials are mixed to prepare a positive electrode slurry for a sodium ion battery.

[0060] In some embodiments, the method for preparing the positive electrode slurry for a sodium ion battery satisfies at least one of the following conditions:

[0061] A. The mixing time is 0.5h-8h, and the rotation speed is 50 rpm-300 rpm;

[0062] Optionally, the mixing time includes 0.5h, 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h or any value between 0.5h-8h, and the rotation speed can be 50 rpm, 100 rpm, 150 rpm, 200 rpm, 250 rpm, 300 rpm or any value between 50 rpm-300 rpm;

[0063] B. The mixing includes: first mixing the binder and the solvent to obtain glue solution A;

[0064] The glue solution, the conductive agent, the weak acid additive and the dehydrating agent are mixed for a second time to obtain glue solution B;

[0065] The gel solution B and the sodium ion battery positive electrode material are mixed for the third time.

[0066] It should be noted that step-by-step mixing can improve the consistency of materials, prevent local uneven mixing, affect the coating effect, affect the surface loading of effective active substances on a single electrode, affect the inconsistent capacity provided by the electrode during charging and discharging, and affect the battery life.

[0067] In some embodiments, the method for preparing the sodium ion battery positive electrode material comprises:

[0068] The raw material of the sodium ion battery positive electrode material is heat-treated under an oxygen atmosphere to obtain the sodium ion battery positive electrode material.

[0069] In some embodiments, the heating rate of the heat treatment is 1°C / min-10°C / min, the sintering temperature is 500°C-950°C, and the time is 12h-20h.

[0070] Optionally, the heating rate of the heat treatment can be 1°C / min, 2°C / min, 4°C / min, 6°C / min, 8°C / min, 10°C / min or any value between 1°C / min-10°C / min, the sintering temperature can be 500°C, 600°C, 700°C, 800°C, 850°C, 900°C, 950°C or any value between 500°C-950°C, and the time can be 12h, 15h, 18h, 20h or any value between 12h-20h.

[0071] It should be noted that in order to allow sodium carbonate to fully melt and participate in the reaction, the maximum sintering temperature is slightly higher than the melting point of sodium carbonate, and it is best to maintain it at 900°C. Considering cost reduction and efficiency improvement, the optimal sintering time is 12 hours. In order to prevent the sodium carbonate from sinking when melting due to too fast a heating rate, resulting in uneven distribution of sodium carbonate in the upper, middle and lower layers, the optimal heating rate is 3°C / min.

[0072] A third aspect of the present application provides a positive electrode plate, comprising the sodium ion battery positive electrode slurry or the sodium ion battery positive electrode slurry prepared by the preparation method of the sodium ion battery positive electrode slurry.

[0073] A fourth aspect of the present application provides a sodium ion battery, comprising the above-mentioned positive electrode plate.

[0074] The fifth aspect of the present application provides an electrical device, including the sodium ion battery.

[0075] In some embodiments, the electrical equipment includes but is not limited to one or more of electric screwdrivers, electric wrenches, electric saws, electric drills, angle grinders, electric two-wheelers, three-wheelers, A00-class electric vehicles, heavy trucks, ships, and energy storage systems.

[0076] The embodiments of the present application will be described in detail below in conjunction with specific examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present application and should not be considered as limiting the scope of the present application. If specific conditions are not specified in the examples, they are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0077] Example 1

[0078] In a first aspect, the present embodiment provides a sodium ion battery positive electrode slurry, wherein the raw materials include: a sodium ion battery positive electrode material, a conductive agent, a binder, a weak acid additive, a dehydrating agent, and a solvent, with a mass ratio of 8:1:1:0.2:0.04:24 respectively;

[0079] The positive electrode material of sodium ion battery is NaCu 0.11 Ni 0.11 Fe 0.33 Mn 0.33 O2, the conductive agent is acetylene black, the binder is polyvinylidene fluoride, the weak acid additive is malic acid, the dehydrating agent is polyacrylamide, and the solvent is N-methylpyrrolidone;

[0080] The preparation method of the positive electrode material of a sodium ion battery comprises the following steps: weighing a sodium-containing metal source raw material and other metal source raw materials according to a stoichiometric ratio, uniformly mixing the other metal source raw materials and the sodium metal source raw material, performing heat treatment, and pulverizing to obtain the positive electrode material, wherein the heating rate of the heat treatment is 3°C / min, the sintering temperature is 900°C, and the sintering time is 12h.

[0081] A second aspect of the present embodiment provides a method for preparing a positive electrode slurry for a sodium ion battery, comprising: mixing the above raw materials evenly with a magnetic stirrer, the speed of the magnetic stirrer being 150 rpm for 7.5 hours, to obtain a positive electrode slurry for a sodium ion battery.

[0082] The picture of the sodium ion battery positive electrode slurry coated on the current collector is as follows Figure 1 shown.

[0083] The third aspect of the present embodiment provides a positive electrode sheet, which is prepared by coating the above-mentioned sodium ion battery positive electrode slurry on aluminum foil, and the specific method is as follows:

[0084] Pour the prepared positive electrode slurry on the surface of the aluminum foil, then adjust the scale of the coater scraper to 30μm, adjust the running speed of the coater to 60cm / min, press the start button, the slurry is slowly coated on the aluminum foil, and then put the electrode into a 120℃ vacuum oven. The running speed of the coater is 60cm / min, and the electrode thickness is 30μm.

[0085] A fourth aspect of this embodiment provides a sodium ion battery, comprising the above-mentioned positive electrode plate.

[0086] Example 2

[0087] In a first aspect, the present embodiment provides a sodium ion battery positive electrode slurry, wherein the raw materials include: a sodium ion battery positive electrode material, a conductive agent, a binder, a weak acid additive, a dehydrating agent, and a solvent, with a mass ratio of 8:1:1:0.2:0.04:20 respectively;

[0088] The positive electrode material of sodium ion battery is NaCu 0.11 Ni 0.11 Fe 0.33 Mn 0.33 O2, the conductive agent is acetylene black, the binder is polyvinylidene fluoride, the weak acid additive is malic acid, the dehydrating agent is polyacrylamide, and the solvent is N-methylpyrrolidone.

[0089] A second aspect of the present embodiment provides a method for preparing a positive electrode slurry for a sodium ion battery, comprising: mixing the above raw materials using a magnetic stirrer to uniformly mix the slurry, the speed of the magnetic stirrer being 150 rpm for 7.5 hours, to obtain a positive electrode slurry for a sodium ion battery;

[0090] The method for preparing the positive electrode material of a sodium ion battery comprises:

[0091] In an oxygen atmosphere, the sodium source: sodium carbonate, copper source: copper oxide, nickel source: nickel oxide, iron source: ferrous oxide, and manganese source: manganese tetraoxide of the sodium ion battery positive electrode material are heat treated to obtain the sodium ion battery positive electrode material. The heating rate of the heat treatment is 3°C / min, the sintering temperature is 900°C-500°C, and the time is 15h.

[0092] The third aspect of this embodiment provides a positive electrode plate, including the above-mentioned sodium ion battery positive electrode slurry, and the preparation method is consistent with that of Example 1.

[0093] A fourth aspect of this embodiment provides a sodium ion battery, comprising the above-mentioned positive electrode plate.

[0094] Example 3

[0095] In a first aspect, the present embodiment provides a sodium ion battery positive electrode slurry, wherein the raw materials include: a sodium ion battery positive electrode material, a conductive agent, a binder, a weak acid additive, a dehydrating agent, and a solvent, with a mass ratio of 8:1:1:0.2:0.04:28 respectively;

[0096] The positive electrode material of sodium ion battery is NaCu 0.11 Ni 0.11 Fe 0.33 Mn 0.33 O2, the conductive agent is carbon nanotubes, the binder is styrene-butadiene rubber, the weak acid additive is malic acid, the dehydrating agent is polyacrylamide, and the solvent is N-methylpyrrolidone.

[0097] A second aspect of the present embodiment provides a method for preparing a positive electrode slurry for a sodium ion battery, comprising:

[0098] The binder and the solvent are mixed using a magnetic stirrer to obtain glue solution A;

[0099] Add the conductive agent, weak acid additive and dehydrating agent into a magnetic stirrer and mix them with the glue solution A to obtain glue solution B;

[0100] Adding the positive electrode material of the sodium ion battery into a magnetic stirrer and mixing it with the glue solution B to obtain the positive electrode slurry of the sodium ion battery;

[0101] The speed of the magnetic stirrer during the whole process was 150 rpm and the duration was 7.5 h;

[0102] The method for preparing the positive electrode material of a sodium ion battery comprises:

[0103] In an oxygen atmosphere, the sodium source: sodium carbonate, copper source: copper oxide, nickel source: nickel oxide, iron source: ferrous oxide, and manganese source: manganese tetraoxide of the sodium ion battery positive electrode material are heat treated to obtain the sodium ion battery positive electrode material. The heating rate of the heat treatment is 3°C / min, the sintering temperature is 900°C, and the time is 12h.

[0104] The third aspect of this embodiment provides a positive electrode plate, including the above-mentioned sodium ion battery positive electrode slurry, and the preparation method is consistent with that of Example 1.

[0105] A fourth aspect of this embodiment provides a sodium ion battery, comprising the above-mentioned positive electrode plate.

[0106] Comparative Example 1

[0107] This comparative example provides a sodium ion battery positive electrode slurry and a preparation method thereof, a positive electrode plate, a sodium ion battery and electrical equipment. The difference from Example 1 is that this comparative example does not provide a weak acid additive and a dehydrating agent, and other conditions are consistent with Example 1.

[0108] The picture of the sodium ion battery positive electrode slurry prepared in this comparative example coated on the current collector is as follows Figure 2 shown.

[0109] Comparative Example 2

[0110] This comparative example provides a sodium ion battery positive electrode slurry and a preparation method thereof, a positive electrode plate, a sodium ion battery and electrical equipment. The difference from Example 1 is that this comparative example does not provide a dehydrating agent, and other conditions are consistent with Example 1.

[0111] Comparative Example 3

[0112] This comparative example provides a sodium ion battery positive electrode slurry and a preparation method thereof, a positive electrode plate, a sodium ion battery and electrical equipment. The difference from Example 1 is that this comparative example does not provide a weak acid additive, and other conditions are consistent with Example 1.

[0113] In order to verify the progress of the embodiments of the present application, electrochemical performance tests were carried out on the samples of the embodiments and the comparative examples, respectively. The method of the electrochemical performance test is as follows: the electrode plates after drying were cut into 16 mm discs, 1M NaClO4 inPC=100with Vo1%3.0%FEC was used as the electrolyte, and CR2025 sodium ion button batteries were assembled in a glove box filled with argon. Then, the batteries were charged and discharged twice at 2-4V and 0.1C (1C=130mAh / g), and then charged and discharged 100 times at 1C. The obtained electrochemical performance parameters are shown in Table 1. The specific test results are shown in Table 1.

[0114] Table 1 Electrochemical performance test

[0115]

[0116] From the above test results, it can be seen from Example 1 and Example 1-3 that after adding the weak acid additive and the dehydrating agent, the capacity and stability of the battery are significantly improved. The synergistic effect of the weak acid additive and the dehydrating agent prevents the slurry from forming gel. The weak acid additive reacts chemically with the residual alkali on the surface of the positive electrode material of the sodium ion battery to produce water, which prevents the residual alkali from attacking the binder and reducing the formation of gel; the dehydrating agent removes water, thereby ensuring that the fluidity of the slurry is not affected and the consistency of the coating is improved, so that the material performance is fully utilized; in Comparative Example 1, neither the weak acid additive nor the dehydrating agent is added , the slurry has high alkalinity and is easy to form gel. The slurry coating is uneven, resulting in thicker local pole pieces, increased internal resistance of the battery, decreased capacity, and reduced cycle performance of the battery; in Comparative Example 2, only a weak acid additive was added, and the pH value of the slurry was reduced. However, the moisture generated by the reaction will cause the battery to fail to charge during the first charging process, affecting the capacity and cycle performance of the battery; in Comparative Example 3, only a dehydrating agent was added, and the pH value of the slurry was relatively high. The residual alkali will increase the viscosity of the slurry and form a gel, which will affect the uniformity of the coating and the quality of the electrode pole pieces, ultimately resulting in low battery capacity and poor cycle performance.

[0117] 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 it. 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 replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0118] In addition, those skilled in the art will appreciate that, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the above claims, any one of the claimed embodiments may be used in any combination. The information disclosed in this background technology section is intended only to deepen the understanding of the overall background technology of the present application and should not be regarded as an admission or in any form of implication that the information constitutes prior art known to those skilled in the art.

Claims

1. A sodium ion battery positive electrode slurry, characterized in that: Its raw materials include: sodium ion battery positive electrode material, conductive agent, binder, weak acid additive, dehydrating agent, solvent; The weak acid additive includes one or more of malic acid, oxalic acid, boric acid, phosphoric acid, citric acid, and sorbic acid; The dehydrating agent includes one or more of polyacrylamide, anhydrous calcium chloride and potassium chloride.

2. The positive electrode slurry for sodium ion battery according to claim 1, characterized in that: The mass ratio of the sodium ion battery positive electrode material, the weak acid additive, the dehydrating agent, the conductive agent, the binder, and the solvent is 8: (0.1-1): (0.01-0.1): (1-3): (1-3): (20-30).

3. The sodium ion battery positive electrode slurry according to claim 1 or 2, characterized in that: At least one of the following conditions is met: A. The positive electrode material of the sodium ion battery includes one or more of transition metal oxides, Prussian blue compounds, polyanion compounds, and organic compounds; B. The conductive agent includes one or more of carbon nanotubes, acetylene black, and graphite; C. The binder includes one or more of polyvinylidene fluoride, polyacrylic acid, and styrene-butadiene rubber; D. The solvent includes one or more of N-methylpyrrolidone, dimethyl sulfoxide, tetrahydrofuran, water, and ethanol.

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 raw materials are mixed to prepare a positive electrode slurry for a sodium ion battery.

5. The method for preparing a positive electrode slurry for a sodium ion battery according to claim 4, characterized in that: At least one of the following conditions is met: A. The mixing time is 0.5h-8h, and the rotation speed is 50 rpm-300 rpm; B. The mixing includes: first mixing the binder and the solvent to obtain glue solution A; The glue solution, the conductive agent, the weak acid additive and the dehydrating agent are mixed for a second time to obtain glue solution B; The gel solution B and the sodium ion battery positive electrode material are mixed for the third time.

6. The method for preparing a positive electrode slurry for a sodium ion battery according to claim 5, characterized in that: The preparation method of the sodium ion battery positive electrode material comprises: The raw material of the sodium ion battery positive electrode material is heat-treated under an oxygen atmosphere to obtain the sodium ion battery positive electrode material.

7. The method for preparing a positive electrode slurry for a sodium ion battery according to claim 6, characterized in that: The heating rate of the heat treatment is 1°C / min-10°C / min, the sintering temperature is 500°C-950°C, and the time is 12h-20h.

8. A positive electrode sheet, characterized in that: A sodium ion battery positive electrode slurry prepared by the method for preparing the sodium ion battery positive electrode slurry according to any one of claims 1 to 3 or the sodium ion battery positive electrode slurry according to any one of claims 4 to 7.

9. A sodium ion battery, characterized in that: Including the positive electrode sheet as described in claim 8.

10. An electrical equipment, characterized in that: Including the sodium ion battery as described in claim 9.

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