Dispersant composition, electrode sheet and battery

Abstract

The present application discloses a dispersant composition, an electrode sheet and a battery. The dispersant composition comprises a flexible polymer and an unsaturated organic substance. The main chain of the flexible polymer contains a single bond; in the dispersant composition, the total molar content of the single bonds contained in the main chain of the flexible polymer is greater than the total molar content of the unsaturated bonds contained in the unsaturated organic substance. The unsaturated organic substance and the flexible polymer in the dispersant composition can play a flexibility enhancement role and a dispersion enhancement role, giving the dispersant composition good dispersion and flexibility modification effects at the same time. The electrode sheet comprises the dispersant composition. The active material layer of at least one of the positive and negative electrode sheets in the battery contains the dispersant composition of the present application.

Description

Technical Field

[0001] The present application belongs to the field of batteries, and specifically relates to a dispersant composition, an electrode sheet and a battery. Background Art

[0002] With the rapid development of mobile electronic devices, electric vehicles and renewable energy, batteries such as lithium-ion batteries, as key energy storage devices, have increasingly higher performance requirements. Among them, high energy density and long life are important performance indicators of batteries, and increasing the solid content of electrode slurry and the thickness of the active material layer of the electrode sheet is an effective way to improve energy density.

[0003] However, in actual operation, due to the high surface energy of electrode active materials such as positive electrode materials, agglomeration is easy to occur during the slurry preparation process, resulting in uneven slurry, high viscosity and other problems, which in turn affect the electrochemical performance and cycle life of the battery. In addition, the electrode active layer formed by the slurry, especially the thick electrode active layer, is prone to cracking, powder loss and other defects due to its internal stress concentration, which seriously affects the processing efficiency and reliability of the battery.

[0004] In view of the above problems, the commonly used solution is to add dispersants to the slurry to reduce the agglomeration of the electrode active materials, thereby improving the dispersion of the electrode active materials and the uniformity of the slurry, reducing the viscosity of the slurry, and thus improving the quality of the pole piece. However, the existing dispersants mainly focus on the effect of reducing and stabilizing the viscosity, mainly solving the gel phenomenon and fluidity problems of the slurry, but it is difficult to effectively solve the problems of crack prevention and flexibility of the pole piece. As a result, the energy density and cycle performance of the battery are effectively improved.

[0005] Therefore, there is an urgent need for a multifunctional additive that can simultaneously solve the problems of the dispersibility of the electrode slurry and the flexibility of the electrode. Summary of the invention

[0006] The purpose of the present application is to overcome the above-mentioned deficiencies of the prior art and to provide a dispersant composition, an electrode sheet and a battery to solve the technical problem that the existing dispersants are difficult to simultaneously take into account the dispersibility of the electrode slurry and the flexibility of the electrode sheet.

[0007] In order to achieve the above application purpose, in the first aspect, the present application provides a dispersant composition. The dispersant composition of the present application comprises a flexible polymer and an unsaturated organic matter, wherein the main chain of the flexible polymer contains a single bond; in the dispersant composition, the total molar content of the single bond contained in the main chain of the flexible polymer is greater than the total molar content of the unsaturated bond contained in the unsaturated organic matter.

[0008] The unsaturated bonds contained in the unsaturated organic matter in the dispersant composition of the embodiment of the present application can act on the single bonds in the main chain of the flexible polymer, so that the internal rotation energy of the single bonds of the main chain of the flexible polymer is reduced, and the single bond angle is increased, so that the single bonds are more likely to rotate internally, thereby improving the flexibility of the flexible polymer; at the same time, the unsaturated bonds can also interact with the single bonds contained in the flexible polymer, which can play a synergistic role in electrophilicity, and can form hydrogen bonds or generate intermolecular interaction forces with, for example, electrode active materials, so that the dispersant of the present application can play the role of a dispersant. Therefore, the unsaturated organic matter can play the role of a flexible synergist and a dispersion modifier for the flexible polymer, and indirectly control the composite ratio relationship between the flexible polymer and the unsaturated organic matter by controlling the total molar ratio of the unsaturated bonds contained therein to the total molar ratio of the single bonds contained in the main chain of the flexible polymer, so that the unsaturated organic matter and the flexible polymer can play a flexible synergistic role and a dispersion synergistic role. When the dispersant composition of the embodiment of the present application is used as a dispersant for electrode slurry, it can give full play to the role of dispersant and softener, effectively reduce the agglomeration of electrode active materials, improve the uniformity and solid content of electrode slurry, reduce the cohesive energy of the active material layer, improve the flexibility and structural stability of the active material layer, reduce the occurrence of cracking of the active material layer, thereby improving the capacity density and cycle performance of the electrode.

[0009] The second aspect of the present application provides an electrode sheet, which comprises an electrode active material and the above-mentioned dispersant composition.

[0010] The electrode sheet of the embodiment of the present application contains the dispersant composition of the embodiment of the present application. Therefore, the electrode active material in the active material layer of the electrode sheet of the embodiment of the present application is evenly dispersed, the internal stress and cohesion of the active material layer are low, the toughness of the active material layer is high, and the structural stability of the active material layer is improved, effectively reducing the occurrence of cracking, powdering and other undesirable phenomena in the active material layer. At the same time, the thickness of the active material layer of the electrode sheet can be increased to form a thick electrode sheet.

[0011] The third aspect of the present application provides a battery. The battery of the present application comprises a positive electrode sheet and a negative electrode sheet, wherein the positive electrode sheet is the electrode sheet of the present application, and the electrode active material contained in the electrode sheet comprises a positive electrode active material; and / or

[0012] The negative electrode sheet is the electrode sheet of the present application, and the electrode active material contained in the electrode sheet includes a negative electrode active material.

[0013] Since at least one of the positive electrode sheet and the negative electrode sheet in the battery of the embodiment of the present application contains the dispersant combination of the embodiment of the present application, the electrode active material contained in the electrode sheet of the battery of the embodiment of the present application is evenly distributed in the active material layer, has a high solid content, and the active material layer has low internal stress and cohesion, and has good flexibility, so that the electrode sheet can be thick, and the electrode sheet has high capacity and structural stability, thereby giving the battery high energy density and cycle performance. DETAILED DESCRIPTION

[0014] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0015] In this application, the term "and / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0016] In this application, "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or multiple, respectively.

[0017] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution, some or all of the steps can be executed in parallel or sequentially, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0018] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0019] The weight of the relevant components mentioned in the embodiment description of the present application can not only refer to the specific content of each component, but also represent the proportional relationship between the weights of the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the embodiment description of the present application, it is within the scope disclosed in the embodiment description of the present application. Specifically, the mass described in the embodiment description of the present application can be a mass unit known in the chemical industry such as μg, mg, g, kg, etc.

[0020] The terms "first" and "second" are used only for descriptive purposes to distinguish objects such as substances from each other, and should not be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. For example, without departing from the scope of the embodiments of the present application, the first XX may also be referred to as the second XX, and similarly, the second XX may also be referred to as the first XX. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0021] In order to meet the market's increasingly higher requirements for battery performance such as energy density and service life, one of the current conventional methods is to increase the solid content of the electrode slurry or further increase the thickness of the active layer of the electrode material contained in the electrode sheet.

[0022] However, it is found in actual production that, since the electrode active materials such as the positive electrode active materials themselves have characteristics such as easy agglomeration, when the solid content of the electrode slurry is increased, the electrode active materials will agglomerate, making the electrode slurry uneven and having high viscosity, thereby resulting in poor uniformity of the formed active material layer. At the same time, due to the existence of internal stress in the active material layer, especially when the thickness of the active material layer is increased in order to increase the energy density of the pole piece, it is easy to cause defects such as cracking and powder falling in the active material layer. In order to effectively improve the uniformity of the electrode slurry and the flexibility of the pole piece, and improve the energy density and cycle performance of the battery, the embodiment of the present application proposes the following technical solution.

[0023] In a first aspect, an embodiment of the present application provides a dispersant composition. The dispersant composition of the embodiment of the present application comprises a flexible polymer and an unsaturated organic matter. Wherein, the main chain of the flexible polymer contains a single bond; and in the embodiment of the present application, the total molar content of the single bonds contained in the main chain of the flexible polymer contained in the flexible polymer is greater than the total molar content of the unsaturated bonds contained in the unsaturated organic matter.

[0024] In the dispersant composition of the present application, the single bond on the flexible polymer main chain refers to a covalent bond formed by sharing a pair of electrons between two atoms on the main chain, which can also be called a saturated bond. The presence of the single bond on the flexible polymer main chain and the good internal rotation of the single bond give the flexible polymer main chain high flexibility. Unsaturated organic matter refers to an organic matter containing unsaturated bonds. The total molar content of the single bonds contained in the main chain of the flexible polymer is greater than the total molar content of the unsaturated bonds contained in the unsaturated organic matter. It can be understood that the mixing ratio requirements of the flexible polymer and the unsaturated organic matter in the dispersant composition of the embodiment of the present application.

[0025] In this way, the main chain of the flexible polymer in the dispersant composition of the embodiment of the present application contains a single bond, so that the flexible polymer can play a flexible role through the internal rotation of the single bond in its main chain. The unsaturated bonds contained in the unsaturated organic matter can act on the single bonds in the main chain of the flexible polymer, so that the internal rotation energy of the single bond of the main chain of the flexible polymer is reduced, the single bond angle is increased, and the single bond internal rotation is easier, thereby improving the flexibility of the flexible polymer, so that the dispersant of the present application can play the role of a flexibilizer.

[0026] At the same time, at least one of the single bonds contained in the polymer main chain and the unsaturated bonds contained in the unsaturated organic matter has good electrophilicity. When the two are compounded, the single bonds and the unsaturated bonds can influence each other, and can play a synergistic role in electrophilicity. They can form hydrogen bonds or generate intermolecular interaction forces with, for example, electrode active materials, so that the dispersant of the present application can play the role of a dispersant, and can be effectively adsorbed on the surface of, for example, electrode active material particles, to alleviate and hinder the direct contact of electrode active material particles, thereby effectively reducing the agglomeration of electrode active material particles.

[0027] Therefore, in the dispersant composition of the embodiment of the present application, the unsaturated bonds contained in the unsaturated organic matter can play the role of a flexibility enhancer and a dispersion modifier for the flexible polymer, and indirectly control the composite ratio between the flexible polymer and the unsaturated organic matter by controlling the total molar ratio of the unsaturated bonds contained therein to the total molar ratio of the single bonds contained in the main chain of the flexible polymer, so that the unsaturated organic matter and the flexible polymer can play a flexibility enhancing role and a dispersion enhancing role. When the dispersant composition of the embodiment of the present application is used as a dispersant for electrode slurry, it can give full play to the role of dispersant and softener, effectively reduce the agglomeration of electrode active materials, improve the uniformity and solid content of electrode slurry, and reduce the cohesive energy of the active material layer, improve the flexibility and structural stability of the active material layer, and reduce the occurrence of cracking defects in the active material layer, thereby improving the capacity density and cycle performance of the electrode.

[0028] In the dispersant composition of the embodiment of the present application, since the total molar amount of single bonds contained in the main chain of the flexible polymer in the flexible polymer is greater than the total molar amount of unsaturated bonds contained in the unsaturated organic matter, the flexible polymer in the flexible polymer constitutes the base component. The flexible polymer and the unsaturated organic matter can simultaneously play the role of a flexible synergist and a dispersant modifier, giving the dispersant composition of the embodiment of the present application good dispersing effect and flexibility modification effect. In some embodiments, in the dispersant composition of the embodiment of the present application, the ratio of the total molar content of single bonds contained in the main chain of the flexible polymer to the total molar content of unsaturated bonds contained in the unsaturated organic matter is 1: (0.015-0.04), which can be optionally 1: (0.025-0.032). In the exemplary example, it can be 1: 0.015, 1: 0.018, 1: 0.02, 1: 0.025, 1: 0.03, 1: 0.035, 1: 0.04, etc. typical but non-limiting molar ratios or the range between any two molar ratios. The molar ratio of the two within this range can enhance the effect of the flexibility enhancer and dispersion modifier between the two, and further improve the dispersion flexibility modification effect of the dispersant composition of the embodiment of the present application.

[0029] Based on the ratio of the total molar content of single bonds contained in the main chain of the above-mentioned flexible polymer to the total molar content of unsaturated bonds contained in the unsaturated organic matter, the mass ratio of the flexible polymer to the unsaturated organic matter can be (0.6-10):1, and can further be (7-9):1. In the exemplary embodiment, it can be 0.6:1, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1 and other typical but non-limiting mass ratios or the range between any two ratios. The mass ratio of the two in this range can enhance the effect of the flexibility enhancer and the dispersion modifier between the two, and further improve the dispersion flexibility modification effect of the dispersant composition of the embodiment of the present application.

[0030] In some embodiments, when the flexible polymer and the unsaturated organic matter in the dispersant composition of the above application examples form a mixture, the flexible polymer has at least the following properties under the action of the unsaturated organic matter. The mixture formed by the flexible polymer and the unsaturated organic matter can be, but is not limited to, both dissolved in a solvent:

[0031] In the embodiment, it has been tested that under the action of unsaturated bonds contained in unsaturated organic matter, such as carbon-carbon double bonds, the CC bond angle of the flexible polymer can be increased from the original 109° to 120°;

[0032] In some embodiments, the single bonds in the flexible polymer main chain contained in the dispersant composition of each embodiment above include at least one of a carbon-carbon single bond, a carbon-nitrogen single bond, and an ether bond. These single bonds not only have relatively high electrophilicity, but also can improve electrophilicity together with unsaturated organic matter, so that the flexible polymer can alleviate and hinder the direct contact of the electrode active material particles, thereby effectively reducing the agglomeration of the electrode active material particles. Moreover, these single bonds have low internal rotation energy, and under the action of unsaturated organic matter, the single bond angle can be increased, making the single bond internal rotation easier, thereby improving the flexibility of the flexible polymer.

[0033] In some embodiments, the molar percentage of the single bonds contained in the flexible polymer in the above embodiments to all the chemical bonds contained in the flexible polymer is 96% to 98%, and can be 97% to 98%. In the exemplary examples, it can be a typical but non-limiting molar content such as 96%, 97%, 98%, or a range between any two molar content values. This content range of single bonds can enhance the flexibility of the flexible polymer, and can also enhance the synergistic effect between the flexible polymer and the unsaturated organic matter, further improving the electrophilicity and flexibility of the flexible polymer.

[0034] In some embodiments, the weight average molecular weight (wt) of the flexible polymer in the above embodiments is 200 to 6000, and can be optionally 200 to 2000. The flexibility of the flexible polymer in this molecular weight range is relatively high.

[0035] In some embodiments, the flexible polymer in the above embodiments may include at least one of polyether and polyester. In the exemplary embodiment, the polyether may include at least one of fatty alcohol polyoxyethylene ether, fatty alcohol polyoxyethylene ether phosphate, phenol polyoxyethylene ether phosphate, phenol polyoxyethylene ether, polyether phosphate, etc.; the polyester may include at least one of polyethylene glycol, polypropylene glycol, polycaprolactone, polycarbonate, poly(hexanediol adipate), poly(butylene adipate), polyurethane, etc. The main chain of these types of flexible polymers contains abundant single bonds as mentioned above, and has good flexibility itself. Moreover, under the synergistic effect of unsaturated organic matter, the single bonds contained therein have a large bond angle, good internal rotation characteristics, and strong electrophilicity, so that the flexible polymer has good flexibility and dispersibility.

[0036] In some embodiments, the unsaturation degree of the unsaturated organic matter contained in the dispersant composition of each embodiment above is 1 to 5, and can be 1 to 3. In the exemplary embodiment, it can be 1, 2, 3, 4, 5, etc., which are typical but non-limiting unsaturations, or a range between any two unsaturation values. This unsaturation range enables the unsaturated organic matter to have an appropriate range of unsaturated bonds, thereby enhancing the synergistic effect between the upper flexible polymers, further improving the electrophilicity and flexibility of the flexible polymers, and thus improving the dispersibility and flexibility of the dispersant composition of the embodiment of the present application.

[0037] In some embodiments, the unsaturated organic matter further contains single bonds, and the total molar content of the single bonds in the unsaturated organic matter is greater than the total molar content of the unsaturated bonds. By selecting an unsaturated organic matter having a molar content of single bonds greater than that of unsaturated bonds, the unsaturated bonds in the unsaturated organic matter can fully exert the above-mentioned effects on the single bonds contained in the flexible polymer, and under the action of the unsaturated bonds, the internal rotation barrier of the single bonds contained in the unsaturated organic matter itself can be reduced, so that the single bond angle is increased, thereby improving the flexibility of the unsaturated organic matter.

[0038] In some embodiments, the unsaturated bonds contained in the unsaturated organic matter in the above embodiments may include at least one of a carbon-carbon double bond (C=C), a carbon-carbon triple bond (C≡C), a carbon-nitrogen triple bond (C≡N), a nitrile group (-C≡N), etc. When these unsaturated bonds with lone pair electrons are in contact with or close to the single bonds of the polymer main chain, the single bond angle of the polymer main chain can be increased, making the single bond easier to rotate internally, and can affect the electrophilicity of the single bond, thereby enhancing the flexibility and dispersibility of the polymer. When the unsaturated organic matter itself contains a single bond, such as when the single bond is greater than the molar content of the unsaturated bond, the unsaturated bond can also adjust the single bond angle contained in the unsaturated organic matter itself, so that the bond angle increases, making the single bond contained in itself easier to rotate internally, and improving the flexibility of the unsaturated organic matter itself.

[0039] In some embodiments, the unsaturated bonds contained in the unsaturated organic matter are connected to the ends of the main chain of the unsaturated organic matter. The unsaturated bonds connected to the ends can still effectively act on the single bonds of the adjacent single-bond flexible polymer main chain, increase the single-bond angle, and improve the flexibility of the flexible polymer; when the unsaturated organic matter itself contains a single bond, it can also reduce the internal rotation barrier of the single bond contained in the unsaturated organic matter, increase the single-bond angle, and improve the flexibility of the unsaturated organic matter itself. Moreover, the characteristics of the unsaturated bonds connected to the ends, such as rigidity, can also enhance the peel strength of the electrode active material layer.

[0040] In an embodiment, the unsaturated bonds connected to the ends may be the unsaturated bonds of the unsaturated organic matter mentioned above. For example, when the unsaturated bonds connected to the ends include a nitrile group, although the nitrile group is generally considered to have strong rigidity, the nitrile group is generally relatively fixed at the end of the main chain, and it can still effectively act on the adjacent single bonds including the single bonds of the flexible polymer main chain and the single bonds that may be contained in the unsaturated organic matter itself, so that the rotation barrier within the single bond is reduced, the single bond angle is increased, and the flexibility of the flexible polymer or further including the unsaturated organic matter is improved. Moreover, the rigidity of the nitrile group itself can enhance the peel strength of the electrode active material layer

[0041] In some embodiments, the distribution of the unsaturated bonds contained in the unsaturated organic matter in the unsaturated organic matter in each of the above embodiments is randomly distributed and / or asymmetrically distributed. Wherein, random distribution can be understood as relatively non-uniform distribution. Unsaturated bonds are randomly distributed and / or asymmetrically distributed in the unsaturated organic matter, the single bond angle contained in the unsaturated organic matter itself can be increased, and the unsaturated organic matter can give full play to the synergistic effect and flexible synergistic effect of the polymer dispersion on the unsaturated organic matter, and the cross-linking reaction that may occur in the unsaturated organic matter can also be reduced and a network structure is formed, and the crystallinity of the unsaturated organic matter is reduced, and the flexible effect of the dispersant composition of the present application embodiment is improved.

[0042] In some embodiments, the unsaturated organic matter in the above embodiments may include at least one of unsaturated fatty acids, unsaturated fatty alcohols, unsaturated fatty amides, olefin nitriles, etc. In the exemplary embodiment, the unsaturated fatty acids may include at least one of oleic acid, linoleic acid, linolenic acid, arachidonic acid, eicosapentaenoic acid, etc.; the unsaturated fatty alcohols may include at least one of oleyl alcohol, trans-octadecenol, leaf alcohol, etc.; the unsaturated fatty amides may include at least one of oleamide, erucamide, etc.; the olefin nitriles may include at least one of acrylonitrile, 3-pentenenitrile, 2-tridecenenitrile, 3-cyclopentyl acrylonitrile, 2,4-hexadienenitrile, 3,7-dimethyl-6-octenonitrile, 3-(thiophene-2-yl) acrylonitrile, etc. These types of unsaturated organic matter have a suitable range of unsaturation, do not contain aromatic rings and other groups, have good flexibility, and when they come into contact with the above flexible polymer, they can further increase the bond angle of the single bond contained in the flexible polymer, improve the internal rotation characteristics of the single bond, and thus can further improve the dispersion and flexibility enhancement effects of the unsaturated organic matter on the polymer. Among them, when the unsaturated organic matter contains olefin nitriles, the olefin nitriles contain appropriate unsaturated bonds, which can significantly reduce the internal rotation barrier of the single bond in the adjacent flexible polymer, and significantly improve the flexibility of the flexible polymer; at the same time, the nitrile group is relatively fixed at one end of the unsaturated organic matter, which will not affect the flexibility of the chain hydrocarbon group in the unsaturated organic matter and the flexible polymer, and the nitrile group can also act as a reinforcing agent to improve the peel strength of the dispersed material.

[0043] In some embodiments, based on the above embodiments, the dispersant composition of the embodiments of the present application may further include at least one component selected from the group consisting of an organic solvent, a lubricant, a leveling agent, an antioxidant, a dispersing aid, an anchoring agent, and a stabilizer.

[0044] In the embodiment, when the above text application embodiment dispersant composition contains an organic solvent, the organic solvent acts as a solvent carrier, and can improve the chemical stability of the flexible polymer and the unsaturated organic matter before application, such as avoiding the unsaturated bonds contained in the unsaturated organic matter from oxidative epoxy reaction. Specifically, at least one of the above flexible polymer and the unsaturated organic matter is dispersed in the organic solvent. In the embodiment, the flexible polymer and the unsaturated organic matter are both dispersed in the organic solvent, and the two are dispersed in the organic solvent at the same time, so that the two can produce mutual influence, so as to give full play to the above dispersion synergistic effect and flexible synergistic effect in the application. In the embodiment, the dispersion can be understood as dissolving, that is, the flexible polymer and the unsaturated organic matter are both dissolved in the organic solvent. In this way, the two can be contacted and influenced by each other between molecules, so as to produce a synergistic effect, and further improve the dispersion synergistic effect and flexible synergistic effect of the above text.

[0045] In the embodiment, the mass ratio of the above flexible polymer to the organic solvent is (0.03-0.15):1, and can be (0.05-0.08):1. In the exemplary embodiment, the mass ratio can be 0.03:1, 0.04:1, 0.05:1, 0.06:1, 0.07:1, 0.08:1, 0.09:1, 0.1:1, 0.12:1, 0.13:1, 0.14:1, 0.15:1, etc., which are typical but non-limiting mass ratios or ranges between any two mass ratios. The mass ratio of the two in this range can improve the dispersibility and / or solubility of the dispersant composition in the organic solvent, improve the uniformity of mixing of the components, and improve the interaction between the components.

[0046] In the embodiment, the organic solvent can be an organic solvent that can effectively dissolve the above flexible polymer and unsaturated organic matter. For example, in the exemplary embodiment, the organic solvent can include at least one of N-methylpyrrolidone, ethanol, toluene, ether, acetone, etc. These types of organic solvents can not only effectively dissolve the above first organic compound and unsaturated organic matter or further dissolve other additives, but also improve the stability of the unsaturated bonds contained in the unsaturated organic matter, so that the two can contact at the molecular level, and enhance the flexibility synergistic effect and dispersion synergistic effect of the two. Of course, it can also be other organic solvents suitable for electrode slurry.

[0047] In the embodiment, when the dispersant composition of the embodiment of the present application contains an antioxidant, the antioxidant may include an antioxidant for protecting the stability of the unsaturated bonds contained in the unsaturated organic matter to improve the stability of the unsaturated bonds contained in the unsaturated organic matter, thereby improving the dispersion synergistic effect between the unsaturated organic matter and the above flexible polymer and the stability of the flexible dispersion synergistic effect. In the embodiment, the mass ratio of the above polymer to the antioxidant in the dispersant composition of the embodiment of the present application can be (3-34): 1, optionally (10-20): 1, and in the exemplary embodiment, it can be 3: 1, 5: 1, 8: 1, 10: 1, 13: 1, 15: 1, 18: 1, 20: 1, 23: 1, 25: 1, 28: 1, 30: 1, 34: 1, etc. Typical but non-limiting mass ratios or ranges between any two mass ratios. The mass ratio of the two in this range can improve the protective effect of the antioxidant on the unsaturated organic matter and improve the stability of the chemical properties of the unsaturated organic matter.

[0048] In an embodiment, the antioxidant may include at least one of N'N-bis-(3-3,5-di-tert-butyl-4-hydroxyphenyl) propionyl) hexamethylenediamine, triethylene glycol di-[β-(3-tert-butyl-4-hydroxy-5-methylphenyl) propionate], tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol, bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, didodecanol thiodipropionate, polysuccinic acid (4-hydroxy-2,2,6,6-tetramethyl-1-piperidinethanol) ester, etc. These types of antioxidants can protect unsaturated organic matter, improve the stability of unsaturated bonds contained in unsaturated organic matter, and improve the stability of chemical properties of unsaturated organic matter.

[0049] In the embodiment, when the dispersant composition of the embodiment of the present application contains a lubricant, the lubricant can improve the surface properties of the dispersed main material, enhance the contact between the above flexible polymer and the unsaturated organic matter and the dispersed main material, thereby assisting the dispersibility of the flexible polymer and the unsaturated organic matter to the dispersed main material. In the embodiment, the mass ratio of the above flexible polymer to the lubricant in the dispersant composition of the embodiment of the present application can be (1.5-20):1, optionally (3-10):1, and in the exemplary embodiment, it can be 1.5:1, 3:1, 5:1, 8:1, 10:1, 13:1, 15:1, 18:1, 20:1 and other typical but non-limiting mass ratios or the range between any two mass ratios. The mass ratio of the two in this range can improve the surface modification effect of the lubricant on the dispersed main material and enhance the contact between the flexible polymer and the unsaturated organic matter dispersed main material.

[0050] In an embodiment, the lubricant may include at least one of acid esters, alkanes, and amide lubricants. In an exemplary embodiment, the acid ester lubricant may include at least one of succinate, tributyl glycerol, and polyacrylate; the alkane lubricant may include but is not limited to paraffin; the amide lubricant may include at least one of sebacic acid amide, lauryl amide, and linoleic acid amide. These types of lubricants have a good modification effect on the surface of the dispersed main material, enhance the wettability of the surface of the dispersed main material, enhance the contact between the polymer and the unsaturated organic matter and the dispersed main material, thereby improving the dispersibility of the dispersed main material.

[0051] In the embodiment, when the dispersant composition of the embodiment of the present application contains a leveling agent, the leveling agent can improve the flatness of the film-forming slurry containing the dispersed main material. In the embodiment, the mass ratio of the above polymer to the leveling agent in the dispersant composition of the embodiment of the present application can be (1.5-20):1, and can be (3-10):1. In the exemplary embodiment, it can be a typical but non-limiting mass ratio of 1.5:1, 3:1, 5:1, 8:1, 10:1, 13:1, 15:1, 18:1, 20:1, etc., or a range between any two mass ratios. The mass ratio of the two in this range can improve the film-forming quality of the slurry containing the dispersed main material of the leveling agent.

[0052] In the embodiment, the leveling agent may include but is not limited to a siloxane leveling agent. In the exemplary embodiment, the siloxane leveling agent may include at least one of dimethyl-3-hydroxypropylmethylsiloxane, γ-glycidyloxypropyltrimethoxysilane, octaphenylcyclotetrasiloxane, 1,2-bis(triethoxysilyl)ethane, hexamethyldisiloxane and tetraethoxysilane. These types of leveling agents not only have a good film layer advection effect, improve the film layer quality such as the flatness and uniformity of the film layer, but also have a water absorption effect.

[0053] In the embodiment, when the dispersant composition of the embodiment of the present application contains a dispersing aid, the dispersing aid can assist the above-mentioned flexible polymer and unsaturated organic matter in the dispersing effect, improve the dispersibility of the dispersed matter; it can also improve the uniformity and stability of the components contained in the dispersant composition in the organic solvent. In the embodiment, the mass ratio of the above polymer to the dispersing aid in the dispersant composition of the embodiment of the present application can be (3-34): 1, and can be optionally (10-30): 1. In the exemplary embodiment, in the exemplary embodiment, it can be 3: 1, 5: 1, 8: 1, 10: 1, 13: 1, 15: 1, 18: 1, 20: 1, 23: 1, 25: 1, 28: 1, 30: 1, 34: 1 and other typical but non-limiting mass ratios or the range between any two mass ratios. The mass ratio of the two in this range can improve the dispersing effect of the dispersing aid, or further improve the uniformity of the dispersion of the components contained in the dispersant composition.

[0054] In an embodiment, the dispersing aid may include an ionic salt dispersant. In a demonstration example, the ionic salt dispersant may include at least one of polyvinyl pyrrolidone, polypropylene alcohol, modified styrene maleic acid quaternary ammonium salt, sodium polyacrylate, etc. These dispersing aids can improve the contact between the above-mentioned flexible polymer and the unsaturated organic matter, thereby improving the flexibility enhancement effect of the unsaturated organic matter on the above-mentioned flexible polymer, and at the same time improve the dispersibility between the components contained in the dispersant composition. Moreover, these dispersing aids can also improve the wettability of the surface of the dispersed object, enhance the contact of the components such as the flexible polymer and the unsaturated organic matter to the dispersed object, thereby improving the dispersibility of the dispersed object. When the dispersant composition is used for the preparation of the pole piece slurry, it can increase the friction between the solids in the pole piece slurry, reduce the cohesion of the solids, improve the dispersibility and stability of the pole piece slurry, and improve the flexibility of the pole piece.

[0055] In the embodiment, when the dispersant composition of the embodiment of the present application contains an anchoring agent, the anchoring agent is respectively combined with the above flexible polymer and the unsaturated organic matter, which can improve the stability of the contact between the flexible polymer and the unsaturated organic matter, thereby improving the flexibility synergistic effect and the dispersion synergistic effect between the unsaturated organic matter and the flexible polymer. It can also play an anchoring role on other components contained in the dispersant composition, thereby improving the dispersibility of the dispersant composition. After contacting with the dispersed object, the anchoring agent can also play an anchoring role on the dispersed object, thereby improving the dispersion stability of the dispersed object.

[0056] In the embodiment, the mass ratio of the above polymer to the anchoring agent in the dispersant composition of the embodiment of the present application can be (1.5-20):1, and can be (10-18):1. In the exemplary examples, the mass ratio of the above polymer to the anchoring agent can be 3:1, 5:1, 8:1, 10:1, 13:1, 15:1, 18:1, 20:1, 23:1, 25:1, 28:1, 30:1, 34:1, etc., which are typical but non-limiting mass ratios, or the range between any two mass ratios. The mass ratio of the two in this range can improve the above-mentioned effect of the anchoring agent.

[0057] In an embodiment, the anchoring agent may include at least one of conjugated olefins, aromatic hydrocarbons, etc. In an exemplary embodiment, the conjugated olefin anchoring agent may include at least one of 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 1,3,5-hexatriene, cyclopentadiene phenanthrene, etc.; the aromatic hydrocarbon anchoring agent may include at least one of 1-methylnaphthalene, 9,10-dibromoanthracene, 9-acetylene phenanthrene, phenanthrenequinone, etc. These anchoring agents can further improve the stability of the contact between the flexible polymer and the unsaturated organic matter, play an anchoring role on other components contained in the dispersant composition and the dispersed matter, and improve the dispersibility of the dispersant composition and the dispersed matter.

[0058] In the embodiment, when the dispersant composition of the embodiment of the present application contains a stabilizer, the stabilizer can play an anchoring role with the solid particles in the electrode slurry, especially the conductive agent such as carbon nanotubes, and can further improve the dispersion stability of the electrode slurry together with other additives such as anchoring agents. In the embodiment, the mass ratio of the above polymer to the stabilizer in the dispersant composition of the embodiment of the present application can be (1.5-20): 1, and can be optionally (10-18): 1. In the exemplary examples, the mass ratio of the above polymer to the stabilizer in the dispersant composition of the embodiment of the present application can be 3: 1, 5: 1, 8: 1, 10: 1, 13: 1, 15: 1, 18: 1, 20: 1, 23: 1, 25: 1, 28: 1, 30: 1, 34: 1, etc., which is typical but not limiting, or the range between any two mass ratios. The mass ratio of the two in this range can improve the above-mentioned effect of the stabilizer.

[0059] In an embodiment, the stabilizer may include at least one of a conjugated olefin, an aromatic hydrocarbon, etc. In an exemplary embodiment, the conjugated olefin stabilizer may include at least one of 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 1,3,5-hexatriene, cyclopentadiene phenanthrene, etc.; the aromatic hydrocarbon stabilizer may include at least one of 1-methylnaphthalene, 9,10-dibromoanthracene, 9-acetylphenanthrene, phenanthrenequinone, etc. The stabilizer may be the same or different from the component type of the above anchoring agent.

[0060] In the embodiment, based on the content of at least one of the above organic solvent, lubricant, leveling agent, antioxidant, dispersing aid, anchoring agent and stabilizer, the dispersant composition may include the following components:

[0061]

[0062] In a further embodiment, the above dispersant composition includes the above lubricant, leveling agent, antioxidant and organic solvent at the same time, and the flexible polymer, unsaturated organic matter, lubricant, leveling agent and antioxidant are dispersed in the organic solvent. In this case, the dispersant composition may include the following components:

[0063]

[0064]

[0065] In a further embodiment, the above dispersant composition includes the above organic solvent, dispersing aid, anchoring agent and stabilizer at the same time, and the flexible polymer, unsaturated organic matter, dispersing aid, anchoring agent and stabilizer are dispersed in the organic solvent. In this case, the dispersant composition may include the following components:

[0066]

[0067] The dispersant composition of the embodiment of the present application contains these additives at the same time and the components contained therein are dissolved in an organic solvent, which can make the components dispersed evenly and stably, improve the functions of the components as described above, and at the same time improve the convenience of using the dispersant composition of the embodiment of the present application.

[0068] In addition, the dispersant composition of the embodiment of the present application can be prepared according to the preparation method of the composition. For example, in the embodiment, the raw materials of each component can be mixed in proportion according to the types and compounding ratios of the components contained in the dispersant composition of the embodiment of the present application in the above embodiments, so that the components are evenly mixed to form a uniformly dispersed and stable mixture.

[0069] In a second aspect, the present application embodiment further provides an electrode sheet. The present application embodiment electrode sheet comprises a current collector and an active material layer disposed on at least one surface of the current collector, the active material layer comprising an electrode active material and a dispersant composition. The dispersant composition is the dispersant composition of the above text application embodiment.

[0070] Since the electrode sheet of the embodiment of the present application contains the dispersant composition of the embodiment of the text application, in this way, in the slurry prepared for forming the active material layer, the polymer and unsaturated organic matter contained in the dispersant composition can play an electrophilic synergistic role, effectively adsorb on the surface of the electrode active material particles, play a dispersing role, reduce the agglomeration phenomenon of the electrode active material particles, thereby improving the uniformity of the dispersion of the electrode active material. Moreover, the unsaturated organic matter can also increase the bond angle of the single bond contained in itself and the single bond contained in the flexible polymer main chain, increase the internal rotation performance of the single bond, so that the unsaturated organic matter and can improve the flexibility of the polymer. Therefore, while the electrode active material is evenly dispersed in the active material layer of the electrode sheet of the embodiment of the present application, the internal stress and cohesion of the active material layer are low, the toughness of the active material layer and its structural stability are high, and the cracking, pulverization and other undesirable phenomena of the active material layer are effectively reduced. At the same time, the thickness of the active material layer of the electrode sheet can be increased to form a thick electrode sheet.

[0071] When the above dispersant composition contains an antioxidant, the antioxidant can improve the stability of the unsaturated bonds contained in the unsaturated organic matter in the electrode sheet, thereby improving the stable role of the unsaturated organic matter in the active material layer of the electrode sheet. When the above dispersant composition contains the above additives such as lubricants, leveling agents, antioxidants, dispersing aids, anchoring agents and stabilizers, it can play a synergistic role between each or more than two components in the active material layer of the sheet or in the electrode slurry, further improve the uniformity of the distribution of the electrode active material in the active material layer, improve the internal stress and cohesion of the active material layer, and improve the toughness and other properties of the active material layer. For example, when other additives contain wetting agents, the contact between the electrode active material in the electrode slurry and the components contained in the dispersant composition can be further improved, thereby further improving the dispersibility of the electrode active material, improving the uniformity of the dispersion of each component and the stability of the dispersion. When the above dispersant composition contains a leveling agent, the quality of the active material layer formed by the electrode slurry will be more flat and uniform, and the quality of the active material layer can be improved.

[0072] In the embodiment, in the electrode sheet of the embodiment of the present application, the mass ratio of the dispersant composition to the electrode active material is 1: (180-1940), and can be optionally 1: (200-1000). This mass ratio range of the two can improve the dispersion performance of the electrode active material and reduce the probability of its agglomeration. At the same time, since the dispersant composition has both dispersing and flexible effects, the content of the dispersant composition in the electrode sheet of the embodiment of the present application can be reduced, thereby increasing the capacity of the electrode sheet of the embodiment of the present application.

[0073] In the embodiment, the active material layer of the electrode sheet of the embodiment of the present application may further include components such as a binder and a conductive agent, or further include components such as a lithium supplement.

[0074] When the active material layer of the electrode sheet of the embodiment of the present application may also include components such as a binder, a conductive agent, a lithium supplement, etc., the binder, the conductive agent, the lithium supplement, etc. components may be in conventional contents, and their materials may be corresponding material types commonly used in the electrode sheet field.

[0075] In the embodiment, the electrode active material contained in the active material base layer of the electrode sheet of the embodiment of the present application can be a positive electrode active material or a negative electrode active material. Among them, when the electrode active material is a positive electrode active material, it can be a lithium battery positive electrode active material or a sodium battery positive electrode active material. At this time, the electrode sheet of the embodiment of the present application is a positive electrode sheet, and the active material layer provided on at least one surface of the positive electrode current collector is a positive electrode active material layer.

[0076] Similarly, when the electrode active material is a negative electrode active material, it can be a lithium battery negative electrode active material or a sodium battery negative electrode active material. In this case, the electrode sheet of the embodiment of the present application is a negative electrode sheet, and the active material layer disposed on at least one surface of the negative electrode current collector is a negative electrode active material layer.

[0077] On the third aspect, the embodiments of the present application also provide a battery. The battery of the embodiments of the present application includes necessary components such as a positive electrode sheet, a negative electrode sheet, a diaphragm or a solid electrolyte, and of course other necessary or auxiliary components. Among them, the diaphragm or solid electrolyte is arranged between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet is the electrode sheet of the above embodiment of the text application, that is, the positive electrode active material layer contained in the positive electrode sheet includes the dispersant composition of the above embodiment of the text application. At this time, the electrode active material contained in the electrode sheet of the above embodiment of the text application includes the positive electrode active material.

[0078] Alternatively, the negative electrode sheet is the electrode sheet of the above application embodiment, that is, the negative electrode active material layer contained in the negative electrode sheet includes the dispersant composition of the above application embodiment. In this case, the electrode active material contained in the electrode sheet of the above application embodiment includes the negative electrode active material.

[0079] Alternatively, the positive electrode sheet is the electrode sheet of the above-mentioned embodiment of the application, in which case the electrode active material contained in the electrode sheet of the above-mentioned embodiment of the application includes the positive electrode active material. Meanwhile, the negative electrode sheet is the electrode sheet of the above-mentioned embodiment of the application, in which case the electrode active material contained in the electrode sheet of the above-mentioned embodiment of the application includes the negative electrode active material.

[0080] Since at least one of the positive electrode sheet and the negative electrode sheet in the battery of the embodiment of the present application is the electrode sheet of the embodiment of the present application, the electrode active material contained in the electrode sheet of the battery of the embodiment of the present application is evenly distributed in the active material layer, has a high solid content, and has low internal stress and cohesion in the active material layer, and has good flexibility, so that the electrode sheet can be thick, and the electrode sheet has high capacity and structural stability, thereby giving the battery high energy density and cycle performance.

[0081] The following uses a number of specific embodiments to illustrate the composite lithium-rich material of the present application, its preparation method, and application.

[0082] 1. Dispersant composition example:

[0083] Embodiment A1:

[0084] The present embodiment A1 to embodiment A6 and comparative examples A1 to comparative examples A2 provide a dispersant composition, respectively. Each dispersant composition contains the combination formula shown in each embodiment in Table 1.

[0085] Each dispersant composition is prepared by mixing the components according to the combination formula shown in each example in Table 1.

[0086] Table 1

[0087]

[0088] 2. Lithium-ion battery example:

[0089] The present embodiment B1 to embodiment B6 and comparative examples B1 to comparative examples B2 provide a lithium ion battery respectively. Each lithium ion battery is assembled into a lithium ion battery according to the following method:

[0090] 1) Positive electrode:

[0091] Under the same conditions, the positive electrode active material: Super P: PVDF: dispersant composition was mixed in a mass ratio of 97:2:1:0.1, the mixing method was ball milling, the ball milling time was 60min, the rotation speed was set to 30Hz, and the solid content was controlled at 61wt% to prepare the positive electrode slurry; the positive electrode slurry was subjected to coating-drying-cutting operations to prepare the positive electrode sheet, and the positive electrode sheet was baked in a vacuum oven at 100°C to remove trace water. Specifically, the positive electrode slurry in Example B1 contains the dispersant composition in Example A1, the positive electrode slurry in Example B2 contains the dispersant composition in Example A2, and so on, the positive electrode slurry in Comparative Example B3 contains the dispersant composition in Comparative Example A3.

[0092] 2) Negative electrode sheet: The negative electrode active material graphite, conductive agent Super P, thickener carboxymethyl cellulose (CMC), and binder styrene butadiene rubber (SBR) are mixed evenly in deionized water to form a negative electrode slurry, wherein the mass ratio of graphite: Super P: CMC: SBR is 95:2:0.5:2.5. The negative electrode slurry is coated on the current collector copper foil, and after drying-rolling-second drying process, the negative electrode sheet is made.

[0093] 3) Diaphragm: Use polyethylene (PE) diaphragm.

[0094] 4) Electrolyte: The electrolyte is a 1 mol / L LiPF6 solution, and the solvent is composed of EC (ethylene carbonate) and DEC (diethyl carbonate) in a volume ratio of 1:1.

[0095] 5) Assembly of secondary batteries:

[0096] The positive electrode sheet, negative electrode sheet, electrolyte and separator are assembled into a lithium-ion soft-pack battery according to the lithium-ion battery assembly requirements.

[0097] Related performance testing of positive electrode slurry and lithium-ion batteries:

[0098] The positive electrode slurries prepared in Section 1) and the lithium-ion batteries of the embodiments and comparative examples assembled in Section 5) were subjected to relevant performance tests as shown in Table 2 below, and the measured results are shown in Table 2 below.

[0099] Among them, the relevant performance test methods in Table 2 are as follows:

[0100] Positive electrode slurry viscosity detection method: After preparing the positive electrode slurry with a solid content of 61%, a viscometer is used to test the viscosity of the positive electrode slurry at room temperature at a speed of 30 rpm after being left for 0.5 h and 24 h.

[0101] The first cycle charging capacity and first cycle efficiency of the battery cell and the capacity retention rate detection method are as follows: the first cycle charging capacity and the first cycle discharging capacity of the lithium ion battery corresponding to the above embodiments and comparative examples are measured, and the first cycle efficiency (first cycle discharging capacity / first cycle charging capacity) is calculated. The test conditions are as follows: constant current and constant voltage charging, the first cycle charging and discharging voltage is 2.0-3.75V, the current is 0.1C, and the cut-off current is 0.01C. After running three laps, the rate is increased to 1C, and the cycle is 1000 laps to observe the capacity retention rate.

[0102] Positive electrode softness test: According to the standard method of "GB / T 8942-2016 Determination of paper softness", cut 3 100mm*100mm electrodes, and perform softness tests 3 times under the conditions of slit width of 20mm and side head depression of 8mm, and take the average value. The higher the softness value obtained, the lower the flexibility of the electrode.

[0103] Table 2

[0104]

[0105] Combined with Table 1 above, it can be seen from the test results in Table 2 that:

[0106] By comparing Example B1 to Example B4, it can be seen that as the proportion of unsaturated organic components in the system increases, the molar ratio of single bonds to unsaturated bonds increases, and there is no obvious difference in the viscosity of each positive electrode slurry at 0.5h. However, at 24h, the viscosity of the positive electrode slurries of Example B1 to Example B4 shows a decreasing trend, that is, as the molar ratio of single bonds to unsaturated bonds increases, the corresponding positive electrode slurry The stabilizing effect of the viscosity is correspondingly improved. The reason for this should be due to the fact that the flexible polymer and unsaturated organic matter in the system, in the presence of additives such as anchoring agents and lubricants, make the adsorption force between the dispersant composition of the embodiment of the present application and the active particles in the positive electrode slurry strong, and the electrostatic effect helps to reduce the viscosity of the slurry; and as time goes by, the lipophilic long chain containing many unsaturated bonds exerts its steric hindrance effect, reduces the sedimentation of solid particles in the positive electrode slurry, plays a role in stabilizing the viscosity, and avoids a rapid increase in viscosity, so that the viscosity of the positive electrode slurry is still lower than 10000mPa·s when the solid content is as high as 61% (such as the viscosity of the positive electrode slurry in Example B3 and Example B3 when it is left to stand for 24h).

[0107] Further comparison of Example B1 to Example B4 shows that the unsaturated bond makes the adjacent single bond internal rotation easier to occur, and the flexibility is increased, which is reflected in the lower softness measurement value. The pole piece is not easy to crack when assembled and buckled, and the stability is high. Even after 1000 cycles, there is still a retention rate of more than 90%. However, the unsaturated bond itself is rigid. When the molar ratio of single bonds to unsaturated bonds in the system reaches 1:0.04 or even above, the pole piece softness value will be significantly increased, and the overall flexibility of the pole piece will be reduced.

[0108] Comparing Example B3 and Example B5, it can be seen that reducing the amount of long-chain carboxylic acid in the unsaturated organic matter and increasing the amount of nitrile group will significantly increase the viscosity of the system. This is because the carboxylic acid has a higher polarity and can be quickly adsorbed on the particle surface, and relies on its own electrostatic effect to enhance the dispersibility of the dispersant composition. The nitrile group mainly enhances the bonding force, and the polarity is not as good as the former, but the nitrile group and the electrolyte ethylene carbonate have a stronger solvophobic effect, which can inhibit the ethylene carbonate dehydrogenation reaction on the surface of the active material to a certain extent, and construct a more stable SEI film. Therefore, the cycle retention rate of the lithium ion battery in Example B5 is higher than the cycle performance of the lithium ion battery in Example B3.

[0109] Comparing Example B3 and Example B6, it can be seen that the presence of the dispersing agent can reduce the viscosity of the slurry, improve the viscosity stabilization effect, and make the final battery cycle stability higher. At the same time, the dispersing agent makes the system more uniform, the coated electrode is smoother, and the softness value measured is lower than that of Example B6 without the dispersing agent.

[0110] Comparison of Example B3 with Comparative Examples A1 and A2 shows that the group containing only flexible polymers has a significantly reduced flexibility, and thus the cycle performance is affected, when the viscosity and battery charge and discharge performance are similar. This is because the unsaturated bond lone pair electrons lack the effect of enhancing the flexibility of the system. The group containing only unsaturated organic matter has a particularly high viscosity and very low flexibility. Its components lack the -CC- and -CO- chemical bonds that can rotate internally, and do not contain -COC- and -OH groups with strong anchoring ability, so the dispersion performance is poor and the electrode stability is low.

[0111] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A dispersant composition comprising a flexible polymer and an unsaturated organic substance, wherein the main chain of the flexible polymer contains single bonds; in the dispersant composition, the total molar content of single bonds contained in the main chain of the flexible polymer is greater than the total molar content of unsaturated bonds contained in the unsaturated organic substance.

2. The dispersant composition according to claim 1, characterized in that: The ratio of the total molar content of the single bonds contained in the main chain of the flexible polymer to the total molar content of the unsaturated bonds contained in the unsaturated organic matter is 1:(0.015-0.04); and / or The mass ratio of the flexible polymer to the unsaturated organic matter is (0.6-10):

1.

3. The dispersant composition according to claim 1 or 2, characterized in that: The weight average molecular weight of the flexible polymer is 200 to 6000; and / or The single bond of the flexible polymer includes at least one of a carbon-carbon single bond, a carbon-nitrogen single bond, and an ether bond; and / or The molar percentage of the single bond in all chemical bonds contained in the flexible polymer is 96% to 98%; and / or The flexible polymer comprises at least one of polyether and polyester; and / or The unsaturated organic matter includes at least one of the following (1) to (3): (1) The unsaturation degree of the unsaturated organic matter is 1 to 5; (2) the unsaturated bond comprises at least one of a carbon-carbon double bond, a carbon-carbon triple bond, a carbon-nitrogen triple bond, and a nitrile group; and / or (3) the unsaturated organic matter comprises at least one of unsaturated fatty acids, unsaturated fatty alcohols, unsaturated fatty amides, and olefin nitriles; (4) the unsaturated organic matter further contains single bonds, and the total molar content of the single bonds in the unsaturated organic matter is greater than the total molar content of the unsaturated bonds in the unsaturated organic matter; (5) The unsaturated bond is connected to the end of the unsaturated organic main chain.

4. The dispersant composition according to claim 3, characterized in that: The unsaturated fatty acid comprises at least one of oleic acid, linoleic acid, linolenic acid, arachidonic acid and eicosapentaenoic acid; and / or The unsaturated fatty alcohol comprises at least one of oleyl alcohol, trans-octadecenol and leaf alcohol; and / or The unsaturated fatty amide includes at least one of oleamide and erucamide; The olefin nitriles include at least one of acrylonitrile, 3-pentenenitrile, 2-tridecenenitrile, 3-cyclopentylacrylonitrile, 2,4-hexadienenitrile, 3,7-dimethyl-6-octenonitrile and 3-(thiophene-2-yl)acrylonitrile.

5. The dispersant composition according to any one of claims 1, 2 and 4, characterized in that: The invention also includes at least one of an organic solvent, a lubricant, a leveling agent, an antioxidant, a dispersing aid, an anchoring agent and a stabilizer.

6. The dispersant composition according to claim 5, characterized in that: The mass ratio of the flexible polymer to the antioxidant is (3-34):1; and / or The mass ratio of the flexible polymer to the lubricant is (1.5-20):1; and / or The mass ratio of the flexible polymer to the leveling agent is (1.5-20):1; and / or The mass ratio of the flexible polymer to the dispersing aid is (3-34):1; and / or The mass ratio of the flexible polymer to the anchoring agent is (1.5-20):1; and / or The mass ratio of the flexible polymer to the stabilizer is (1.5-20):1; and / or The mass ratio of the flexible polymer to the organic solvent is (0.03-0.15):1; and / or The antioxidant comprises at least one of N'N-bis-(3-3,5-di-tert-butyl-4-hydroxyphenyl) propionyl) hexamethylenediamine, triethylene glycol bis[β-(3-tert-butyl-4-hydroxy-5-methylphenyl) propionate], tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol, bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, didodecanol thiodipropionate, and poly(4-hydroxy-2,2,6,6-tetramethyl-1-piperidinylethanol) succinate; and / or The lubricant comprises at least one of acid esters, alkanes and amide lubricants; and / or The leveling agent includes a siloxane leveling agent; and / or The dispersing aid comprises an ionic salt dispersant; and / or The anchoring agent comprises at least one of a conjugated olefin and an aromatic hydrocarbon; and / or The stabilizer includes at least one of conjugated olefins and aromatic hydrocarbons.

7. The dispersant composition according to claim 5, characterized in that: The dispersant composition comprises the organic solvent, the lubricant, the leveling agent, and the antioxidant, wherein the flexible polymer, the unsaturated organic matter, the lubricant, the leveling agent, and the antioxidant are dispersed in the organic solvent, and the mass fractions of the organic solvent, the flexible polymer, the unsaturated organic matter, the lubricant, the leveling agent, and the antioxidant are as follows: 3 to 10 parts of the flexible polymer 1 to 5 parts of the unsaturated organic matter 0.5 to 2 parts of the lubricant 0.5 to 2 parts of the leveling agent 0.3 to 1.0 parts of the antioxidant 80 to 95 parts of the organic solvent; or The dispersant composition comprises the organic solvent, the dispersing aid, the anchoring agent and the stabilizer, wherein the flexible polymer, the unsaturated organic matter, the dispersing aid, the anchoring agent and the stabilizer are dispersed in the organic solvent, and the mass fractions of the organic solvent, the flexible polymer, the unsaturated organic matter, the dispersing aid, the anchoring agent and the stabilizer are as follows: 3 to 10 parts of the flexible polymer 1 to 5 parts of the unsaturated organic matter 0.3 to 1.0 parts of the dispersing aid 0.5 to 2.0 parts of the anchoring agent 0.5 to 2.0 parts of the stabilizer The organic solvent is 80 to 95 parts.

8. An electrode sheet, characterized in that: The invention comprises an electrode active material and the dispersant composition according to any one of claims 1 to 7.

9. The electrode sheet according to claim 8, characterized in that: The mass ratio of the dispersant composition to the electrode active material is 1:(180-1940).

10. A battery comprising a positive electrode sheet and a negative electrode sheet, characterized in that: The positive electrode sheet is the electrode sheet according to any one of claims 8 to 9, and the electrode active material contained in the electrode sheet includes a positive electrode active material; and / or The negative electrode sheet is the electrode sheet according to any one of claims 8 to 9, and the electrode active material contained in the electrode sheet includes a negative electrode active material.

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