Conductive agent precursor, electrode plate and battery

Abstract

The invention provides a conductive agent precursor, an electrode plate and a battery, the conductive agent precursor comprises a 1, 3-butadiyne derivative, and the 1, 3-butadiyne derivative comprises aryl and / or aliphatic hydrocarbon. When the conductive agent precursor provided by the invention is applied to the electrode plate, the resistance of the electrode plate is relatively small, so that the impedance of the battery is relatively small.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of electrochemistry, and particularly relates to a conductive agent precursor, an electrode sheet and a battery. BACKGROUND

[0002] Lithium ion batteries are widely used in new energy vehicles, consumer electronics, energy storage systems and other fields as high-energy-density energy storage devices. The core performance indicators thereof include energy density, cycle life, rate charge-discharge capability and safety. In the process of preparing an electrode sheet, a conductive agent is a key auxiliary material for constructing a three-dimensional conductive network, and the conductive agent functions to efficiently conduct electrons to the surface of an active material, reduce the resistance of the electrode sheet and improve the overall electrochemical performance of the battery. Especially in high-capacity active materials (such as silicon-based negative electrodes), the conductive agent also needs to inhibit cracks caused by the volume expansion of the material and maintain the stability of the electrode structure.

[0003] However, the electrode sheet of the prior art has a large resistance, so that the battery has a large impedance. SUMMARY

[0004] The main purpose of the present application is to provide a conductive agent precursor, which is applied to an electrode sheet, so that the electrode sheet has a low resistance, thereby making the battery have a low impedance.

[0005] The present application also provides an electrode sheet comprising a conductive agent prepared from the above-mentioned conductive agent precursor, so that the electrode sheet has a low resistance, thereby making the battery have a low impedance.

[0006] The present application also provides a battery comprising the above-mentioned electrode sheet, so that the battery has a low impedance.

[0007] In a first aspect, the present application provides a conductive agent precursor comprising a 1,3-butadiyne derivative, wherein the 1,3-butadiyne derivative comprises an aromatic group and / or an aliphatic group.

[0008] As an implementation form, the conductive agent precursor as described above, wherein the aromatic group comprises at least one of a phenyl group, a thiophene group, a perylene group, an anthracene group and a pyrene group.

[0009] As an implementation form, the aliphatic group comprises a C4-C 16 aliphatic group.

[0010] As an implementation form, the conductive agent precursor as described above, wherein the 1,3-butadiyne derivative further comprises a heteroatom.

[0011] As an implementation form, the heteroatom comprises at least one of N, P, B, S and Cl.

[0012] As one embodiment, in the conductive agent precursor described above, the aromatic group comprises a conjugated group having 14 or more carbon atoms.

[0013] As one embodiment, in the conductive agent precursor described above, the conjugated group includes at least one selected from perylene diimide, perylene diimide derivative, anthracene, anthracene derivative, pyrene, and pyrene derivative.

[0014] As one embodiment, in the conductive agent precursor described above, the aromatic and / or aliphatic hydrocarbon groups include electron-donating and / or electron-withdrawing groups;

[0015] In one embodiment, the electron-donating group includes alkyl and / or methoxy groups;

[0016] In one embodiment, the electron-withdrawing group includes at least one of halogen, cyano, and trifluoromethyl.

[0017] As one embodiment, the conductive agent precursor described above further includes a polar group in the aromatic group and / or aliphatic hydrocarbon group;

[0018] In one embodiment, the polar group includes at least one of phenol derivative group, carboxyl group, and amino group.

[0019] As one embodiment, the conductive agent precursor described above includes 1,3-butadiyne derivatives containing aromatic groups and 1,3-butadiyne derivatives containing aliphatic hydrocarbon groups.

[0020] In one embodiment, the mass ratio of the 1,3-butadiene derivative containing an aromatic group to the 1,3-butadiene derivative containing an aliphatic hydrocarbon group is (5~100):1.

[0021] In a second aspect, the present invention provides an electrode sheet comprising a current collector and an active material layer present on at least one side of the current collector, the active material layer comprising a conductive agent prepared from a conductive agent precursor as described above.

[0022] Thirdly, the present invention provides a battery comprising the electrode plates described above.

[0023] The conductive agent precursor provided by this invention includes a 1,3-butadiyne derivative, which comprises an aromatic group and / or an aliphatic hydrocarbon group. The core skeleton of the 1,3-butadiyne derivative is a core unsaturated conjugated structure of a -C alkyne derivative, possessing both high reactivity and electron delocalization capability. When an aromatic group is introduced into the derivative, the aromatic ring and the butadiyne chain can form a large π-conjugated system, significantly enhancing the electron transport potential of the molecule. When an aliphatic hydrocarbon group is introduced, the flexible characteristics of the aliphatic chain can effectively improve the dispersibility of the conductive agent precursor in the electrode slurry, preventing molecular aggregation. Therefore, when this conductive agent precursor is applied to an electrode sheet, it can reduce the resistance of the electrode sheet, thereby reducing the impedance of the battery. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the accompanying drawings used in the description of the embodiments of the present invention or related technologies are briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 The proton spectrum of the 1,3-butadiyne derivative of Example 1 provided by the present invention;

[0026] Figure 2 Raman spectra of the 1,3-butadiene derivative of Example 1 provided by the present invention before and after polymerization. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0028] Lithium-ion batteries, as high-energy-density energy storage devices, are widely used in new energy vehicles, consumer electronics, and energy storage systems. Their core performance indicators include energy density, cycle life, rate charge / discharge capability, and safety. In the electrode fabrication process, conductive agents are key auxiliary materials for constructing a three-dimensional conductive network. Their role is to efficiently conduct electrons to the surface of the active material, reduce electrode resistance, and improve the overall electrochemical performance of the battery. Especially in high-capacity active materials (such as silicon-based anodes), conductive agents also need to suppress crack defects caused by material volume expansion and maintain electrode structural stability.

[0029] However, electrode sheets prepared by existing technologies generally suffer from high resistance, which directly leads to an increase in the overall impedance of the battery and severely restricts the full realization of battery performance. Specifically, traditional conductive agents (such as carbon black and conductive graphite) are mainly dispersed between active materials through physical mixing. The resulting conductive network has significant defects: First, the contact between the conductive agent and the active material particles is mostly point contact or limited line contact, resulting in high contact resistance and poor electron transport path; Second, during the coating and drying process of the electrode slurry, the conductive agent is prone to agglomeration or uneven distribution, making it difficult to form a continuous and stable three-dimensional conductive framework, and even conductive blind spots exist in some areas.

[0030] The inventors of this application have discovered through research that if a 1,3-butadiyne derivative is used as a conductive agent precursor, and then added to the slurry and coated onto the electrode sheet to form a conductive agent, the resistance of the electrode sheet can be significantly reduced, thereby reducing the impedance of the battery.

[0031] Based on this, in a first aspect, the present invention provides a conductive agent precursor comprising a 1,3-butadiyne derivative, wherein the 1,3-butadiyne derivative comprises an aromatic group and / or an aliphatic hydrocarbon group. It will be understood that the aromatic group in the present invention comprises substituted and / or unsubstituted aromatic groups, and the aliphatic hydrocarbon group comprises substituted and / or unsubstituted aliphatic hydrocarbon groups.

[0032] The conductive precursor provided by this invention, when applied to electrode sheets, can reduce the resistance of the electrode sheets, thereby reducing the impedance of the battery. This is because the core skeleton of the 1,3-butyne derivative is an -C≡CC≡C- unsaturated conjugated structure, possessing both high reactivity and electron delocalization capability. When aromatic groups are introduced into the derivative, the aromatic ring and the butyne chain can form a large π-conjugated system, significantly enhancing the electron transport potential of the molecule. When aliphatic hydrocarbon groups are introduced, the flexible characteristics of the aliphatic chain can effectively improve the dispersibility of the precursor in the electrode slurry, preventing molecular aggregation. Simultaneously, the π-π stacking effect of the aromatic groups can promote the graphitization degree of the product after precursor conversion, while the aliphatic hydrocarbon groups can enhance the interfacial compatibility between the precursor and the electrode active material and binder, laying a structural foundation for the subsequent construction of the conductive network.

[0033] During the preparation of the electrode sheet, the conductive agent precursor of this invention undergoes a controllable cross-linking reaction, and the 1,3-butyne derivative undergoes addition polymerization to form a polybutyne polymer with a conjugated structure. Its π electrons can migrate freely, exhibiting excellent intrinsic conductivity. The above conversion process is an in-situ growth process. The conductive agent formed after conversion can form continuous conductive bridges between and on the surface of the active material particles, effectively filling the gaps between the active material particles. This solves the problem of discontinuous conductive networks caused by the easy agglomeration of traditional conductive agents (carbon black, carbon nanotubes, etc.), significantly reducing the contact resistance between active material particles and the bulk resistance of the electrode.

[0034] Therefore, the conductive agent precursor provided by the present invention includes a 1,3-butadiyne derivative, which includes an aromatic group and / or an aliphatic hydrocarbon group. When applied to an electrode sheet, it can reduce the resistance of the electrode sheet, thereby reducing the impedance of the battery.

[0035] In some embodiments of the present invention, the aromatic group includes at least one selected from phenyl, thiophene, perylene, anthracene, and pyrene. This can further reduce the interfacial contact resistance of the electrode sheet and reduce the impedance of the battery. In the present invention, phenyl, thiophene, perylene, anthracene, and pyrene include substituted and / or unsubstituted phenyl, substituted and / or unsubstituted thiophene, substituted and / or unsubstituted perylene, substituted and / or unsubstituted anthracene, and substituted and / or unsubstituted pyrene.

[0036] In some embodiments, aliphatic hydrocarbon groups include C4~C6. 16 (For example, it can be C4, C6, C8, C...) 10 C 12 C 16 (or any combination thereof) of aliphatic hydrocarbon groups. This can further inhibit the aggregation of the conductive agent precursor molecules themselves, so that the conductive agent precursor is uniformly dispersed in the active material layer of the electrode sheet, reducing the resistance of the electrode sheet, thereby reducing the impedance of the battery.

[0037] In some embodiments of the present invention, the 1,3-butadiyne derivative further includes heteroatoms. Preferably, the heteroatoms include at least one of N, P, B, S, and Cl. Doping with these heteroatoms alters the Fermi level position of the conductive agent, bringing it closer to the conduction band or valence band, reducing the energy required for electron transitions, and making it easier for electrons to participate in conduction. Simultaneously, the doped heteroatoms also provide additional free electrons or holes, further increasing the conductivity of the electrode sheet, i.e., reducing the resistance of the electrode sheet, thereby reducing the impedance of the battery.

[0038] Specifically, the aforementioned heteroatoms can be doped into substituents in substituted aromatic groups and / or substituents in substituted aliphatic hydrocarbon groups.

[0039] In some embodiments of the invention, the aromatic group comprises a conjugated group having 14 or more carbon atoms. Exemplarily, the number of carbon atoms may include a range of 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 30, 35, or any combination thereof.

[0040] Preferably, the conjugated group includes at least one selected from perylene diimide, perylene diimide derivative, anthracene, anthracene derivative, pyrene, and pyrene derivative.

[0041] Because 1,3-butyne derivatives are small molecules with high rigidity and are not easily deformed, the aforementioned conjugated groups can effectively disperse the local electron cloud density of the molecule, avoiding excessive local charge that could trigger side reactions.

[0042] In some embodiments of the present invention, the aromatic and / or aliphatic hydrocarbon groups include electron-donating and / or electron-withdrawing groups. These groups can flexibly adjust the Fermi level position of the conductive agent, bringing it closer to the conduction band or valence band, lowering the electron transition energy barrier, thereby adapting it to high-voltage battery systems and reducing side reactions. Simultaneously, the electrochemical window of the conductive agent can also be flexibly controlled.

[0043] Specifically, electron-donating groups include alkyl and / or methoxy groups.

[0044] Specifically, the electron-withdrawing group includes at least one of halogen, cyano, and trifluoromethyl.

[0045] The specific types of electron-donating and / or electron-withdrawing groups mentioned above can further flexibly adjust the Fermi level position of the conductive agent and flexibly control the electrochemical window of the conductive agent.

[0046] In some embodiments of the present invention, the aromatic and / or aliphatic hydrocarbon groups further include polar groups. Modification with polar groups enhances the interfacial interactions (e.g., hydrogen bonding, electrostatic interactions) between the conductive agent and other active materials in the electrode sheet, suppresses crack defects caused by volume expansion of the active material, and ensures that the conductive agent can efficiently transport electrons from the current collector to the surface of the active material, thereby reducing the resistance of the electrode sheet and lowering the impedance of the battery.

[0047] Preferably, the polar group includes at least one of phenol derivative group, carboxyl group, and amino group.

[0048] The types of polar groups mentioned above can further reduce the resistance of the electrode sheets and the impedance of the battery.

[0049] In some embodiments of the present invention, the 1,3-butadiyne derivatives include 1,3-butadiyne derivatives containing aromatic groups and 1,3-butadiyne derivatives containing aliphatic hydrocarbon groups. The 1,3-butadiyne derivatives containing aromatic groups can form a two-dimensional graphite structure, i.e., a conjugated plane, in which electrons can be efficiently transported along the conjugated plane. The 1,3-butadiyne derivatives containing aliphatic hydrocarbon groups can construct interlayer conductive bridges, increasing the electron transport efficiency between layers, thereby improving the conductivity of the electrode sheet, reducing the resistance of the electrode sheet, and reducing the impedance of the battery.

[0050] Preferably, the mass ratio of the 1,3-butadiyne derivative containing an aromatic group to the 1,3-butadiyne derivative containing an aliphatic hydrocarbon group is (5~100):1, for example, it can be a range of 5:1, 10:1, 20:1, 40:1, 80:1, 100:1 or any two of them.

[0051] This can further improve the planar transport efficiency and interlayer transport efficiency of electrons, reduce the resistance of the electrode sheets, and reduce the impedance of the battery.

[0052] By way of example, the present invention provides a method for preparing the above-mentioned conductive agent precursor, comprising the following steps:

[0053] Under the action of a catalyst, a coupling reaction is carried out on a raw material system including alkynes to obtain a conductive agent precursor.

[0054] Specifically, acetylene raw materials can be mixed and then subjected to an asymmetric Hay coupling reaction in the presence of a catalyst, such as Cu, to prepare 1,3-butyne derivatives, i.e., conductive agent precursors.

[0055] Secondly, the present invention provides an electrode sheet comprising a current collector and an active material layer present on at least one side of the current collector, the active material layer comprising a conductive agent prepared from the aforementioned conductive agent precursor. Therefore, the electrode sheet has low resistance, thereby resulting in low battery impedance.

[0056] By way of example, the present invention provides a method for preparing the above-mentioned electrode sheet, comprising the following steps:

[0057] An electrode sheet is prepared by coating an electrode slurry including a conductive agent precursor onto at least one side of a current collector and drying it to form an active material layer; the conductive agent precursor includes a 1,3-butadiyne derivative, which includes an aromatic group and / or an aliphatic hydrocarbon group.

[0058] Specifically, the active material, 1,3-butadiyne derivative, binder, and dispersant can be dispersed in a solvent in a certain proportion. The viscosity of the electrode slurry can be adjusted by adjusting the amount of solvent added. Preferably, the ratio of the active material, 1,3-butadiyne derivative, binder, and dispersant can be (95~97):(1~2):(1~2):1.

[0059] 1,3-Butadiyne derivatives are conjugated small molecule monomers that can dissolve in the dispersion solvent during the mixing process of electrode slurry. They can be polymerized in situ under certain conditions to form a conductive graphite structure, thus acting as a conductive agent.

[0060] This small molecule can dissolve well in the dispersion solvent during the preparation of electrode slurry, which can solve the problem of difficult dispersion of conductive agent, thereby achieving excellent solidification and viscosity reduction effect.

[0061] Meanwhile, the solubility of small-molecule monomers can reduce the agglomeration problem of traditional carbon-based materials. Furthermore, the solubility of small-molecule monomers eliminates the need for energy-intensive dispersion equipment during electrode slurry preparation, significantly reducing production costs.

[0062] Through polymerization, 1,3-butadiyne derivatives can react to form one-dimensional conductive long chains with alternating ene and alkyne groups. When the 1,3-butadiyne derivative includes aromatic groups, there are more selectable reaction sites, resulting in a two-dimensional graphite structure. Highly conductive agents can be prepared in situ within the electrode sheet by controlling the degree of polymerization and heteroatom doping.

[0063] Specifically, the polymerization reaction can be carried out under light and / or heating conditions.

[0064] Preferably, the heating conditions for the polymerization reaction include: a heating temperature of 100~180℃ and a heating time of 1~3h.

[0065] The polymerization reaction of small-molecule 1,3-butadiyne derivatives can be activated by thermal energy to form a highly conductive graphite structure through topological polymerization, thus creating a conductive agent. Heating time affects the conversion rate of the polymerization reaction, specifically the conversion rate of the conductive agent precursor into the conductive agent, thereby influencing the resistance of the electrode sheet.

[0066] The electrode sheet preparation method provided by the present invention can prepare the above-mentioned electrode sheet, and the electrode sheet has low resistance, so that when applied to a battery, the battery impedance is low.

[0067] In some embodiments of the present invention, the 1,3-butadiyne derivative has the following structure:

[0068]

[0069] R1 and R2 are each independently selected from aromatic groups and / or aliphatic hydrocarbon groups.

[0070] This can further reduce the resistance of the electrode plates and reduce the impedance of the battery.

[0071] Thirdly, the present invention provides a battery comprising the electrode plates as described above, thereby providing a battery with low impedance.

[0072] In addition to the electrode plates, the battery of the present invention also includes a separator and an electrolyte. The separator can be a separator conventionally used in the art, such as a PP membrane or a PE membrane. The electrolyte can also be an electrolyte conventionally used in the art.

[0073] The battery of the present invention can be prepared using conventional methods in the art. Specifically, the positive electrode, separator and negative electrode can be stacked in sequence to obtain the cell, and then the battery can be obtained by hot pressing, liquid injection, formation and packaging.

[0074] The technical solution of the present invention will be further described below with reference to specific embodiments.

[0075] Example 1

[0076] The method for preparing the conductive agent precursor in this embodiment includes the following steps:

[0077] 0.12 mol of p-aminophenylacetylene and 0.1 mol of 2-ethynylthiophene were mixed and subjected to an asymmetric Hay coupling reaction using Cu as a catalyst to prepare 1,3-butyne derivative A, the precursor of the conductive agent, with the structure shown below:

[0078] .

[0079] The electrode sheet preparation method of this embodiment includes the following steps:

[0080] The main material (lithium iron phosphate), conductive agent precursor (1,3-butadiyne derivative A), binder (PVDF), and dispersant (PVP) were dispersed in an NMP solution at a mass ratio of 96:1:2:1 to obtain a positive electrode slurry. The amount of NMP added was adjusted to achieve a solid content of 75% in the positive electrode slurry. Using a slot extrusion process, the positive electrode slurry was coated onto both sides of an aluminum foil at a speed of 12 m / min, maintaining a foil tension of 5 N / m. After drying in a segmented oven (60℃-120℃-40℃) for 15 min, it was wound up to obtain the positive electrode precursor. The positive electrode precursor was heated at 150℃ for 120 min to obtain the positive electrode sheet. During this process, 1,3-butadiyne derivative A underwent a polymerization reaction. The process ensured that 1,3-butadiyne derivative A could undergo in-situ topological polymerization while maintaining a moisture content of <30 ppm and a solvent residue of <500 ppm in the positive electrode sheet. The positive electrode sheet was rolled and slit under 10T pressure, and the resistance of the positive electrode sheet was tested.

[0081] Example 2

[0082] The preparation methods of the conductive agent precursor and electrode sheet in this embodiment are basically the same as those in Example 1. The difference is that the conductive agent precursor in this embodiment includes 1,3-butadiyne derivative A and 1,3-butadiyne derivative B.

[0083] The structure of 1,3-butadiyne derivative A is shown in the following formula:

[0084] ;

[0085] The structure of 1,3-butadiyne derivative B is shown in the following formula:

[0086] .

[0087] The electrode sheet preparation method of this embodiment includes the following steps:

[0088] 1,3-Butadiyne derivative A and 1,3-Butadiyne derivative B (10,12-tetradecanoic acid) were mixed at a mass ratio of 5:1 to obtain the 1,3-butadiyne derivative of this embodiment. The main material (lithium iron phosphate), 1,3-butadiyne derivative, binder (PVDF), and dispersant (PVP) were dispersed in an NMP solution at a mass ratio of 96:1:2:1 to obtain a positive electrode slurry. The amount of NMP added was adjusted to achieve a solid content of 75% in the positive electrode slurry. Using a slot extrusion process, the positive electrode slurry was coated onto aluminum foil at a speed of 12 m / min, maintaining a foil tension of 25 N / m. After drying in a segmented oven (60℃-120℃-40℃) for 15 min, it was wound up to obtain the positive electrode precursor. The positive electrode precursor was heated at 150℃ for 120 min to obtain the positive electrode. During this process, the 1,3-butadiyne derivative underwent a polymerization reaction. This process ensured that the 1,3-butadiyne derivative could undergo in-situ topological polymerization while maintaining the moisture content of the positive electrode at <30 ppm and the solvent residue at <500 ppm. The positive electrode was then rolled and slit under 10T pressure, and its resistance was tested.

[0089] Example 3

[0090] The preparation methods of the conductive agent precursor and electrode sheet in this embodiment are basically the same as those in Example 1, except that the structure of the 1,3-butadiyne derivative in the conductive agent precursor is as shown in the following formula:

[0091] .

[0092] Example 4

[0093] The preparation methods of the conductive agent precursor and electrode sheet in this embodiment are basically the same as those in Example 1, except that the structure of the 1,3-butadiyne derivative in the conductive agent precursor is as shown in the following formula:

[0094] .

[0095] Example 5

[0096] The preparation methods of the conductive agent precursor and electrode sheet in this embodiment are basically the same as those in Example 1, except that the structure of the 1,3-butadiyne derivative in the conductive agent precursor is as shown in the following formula:

[0097] .

[0098] Example 6

[0099] The preparation methods of the conductive agent precursor and electrode sheet in this embodiment are basically the same as those in Example 1, except that the structure of the 1,3-butadiyne derivative in the conductive agent precursor is as shown in the following formula:

[0100] .

[0101] Example 7

[0102] The preparation methods of the conductive agent precursor and electrode sheet in this embodiment are basically the same as those in Example 1, except that the heating time of the positive electrode precursor is 90 min.

[0103] Example 8

[0104] The preparation methods of the conductive agent precursor and electrode sheet in this embodiment are basically the same as those in Example 1, except that the heating time of the positive electrode precursor is 150 min.

[0105] Example 9

[0106] The preparation methods of the conductive agent precursor and electrode sheet in this embodiment are basically the same as those in Example 1, except that the heating time of the positive electrode precursor is 180 min.

[0107] Comparative Example 1

[0108] The preparation method of the electrode sheet in this comparative example includes the following steps:

[0109] The main material (lithium iron phosphate), conductive agent conductive carbon black, binder polyvinylidene fluoride (PVDF), and dispersant (PVP) were dispersed in an NMP solution at a mass ratio of 96:1:2:1 to obtain a positive electrode slurry. The amount of NMP added was adjusted to achieve a solid content of 75% in the positive electrode slurry. Using a slot extrusion process, the positive electrode slurry was coated onto both sides of an aluminum foil at a speed of 12 m / min, maintaining a foil tension of 5 N / m. After drying in a segmented oven (60℃-120℃-40℃) for 15 min, the foil was wound up to obtain the positive electrode sheet.

[0110] Experimental example:

[0111] 1. Proton NMR spectrum: The proton NMR spectrum of 1,3-butadiyne derivative small molecules was tested in accordance with the "General Rules for Quantitative Nuclear Magnetic Resonance Spectroscopy Proton NMR Internal Standard Method".

[0112] 2. Raman spectra: Raman spectra of 1,3-butadiyne derivatives were obtained before and after polymerization using a Raman spectrometer. The testing method was in accordance with JY / T 0573-2020, "General Rules for Laser Raman Spectroscopy Analysis".

[0113] 3. Resistance of electrode sheets: The resistivity of the electrode sheets in each embodiment and comparative example was tested using an FT-341 four-probe tester. The test method was in accordance with YB / T 6166-2024, "Determination of sheet resistance of graphene thin film by four-probe method".

[0114] 4. Impedance: At 25°C and normal pressure (0.1MPa), the positive and negative electrodes of each embodiment and comparative example were made of graphite, and the separator was made of polypropylene. The electrolyte (composed of 1mol / L LiPF6, solvent EC / DMC / DEC=v / v / v:1 / 1 / 1) was used to form a full cell.

[0115] The impedance of a full cell was tested using a Princeton impedance meter.

[0116] 5. Under the same slurry solid content, using a No. 4 rotor and a rotation speed of 60 rpm, test the viscosity of the positive electrode slurry of the example and comparative examples.

[0117] Figure 1 The proton NMR spectrum of the 1,3-butyne derivative of Example 1 provided by the present invention is shown below. Figure 1 It can be demonstrated that the synthesis of 1,3-butyne derivatives from p-aminophenylacetylene and 2-ethynylthiophene in Example 1 yielded a 1,3-butyne derivative. Figure 2 Raman spectra of the 1,3-butyne derivative of Example 1 provided by the present invention before and after polymerization, from Figure 2 It can be seen that the 1,3-butadiyne derivative of Example 1, after polymerization, has a 1400 cm⁻¹ diameter. -1 and 1580cm -1 The nearby signals were significantly enhanced, corresponding to the D and G peaks of graphite, respectively, proving that the 1,3-butadiyne derivative formed a graphite structure through in-situ polymerization.

[0118] Table 1

[0119]

[0120] As shown in Table 1, compared with the comparative example, the conductive agent precursor provided by the present invention includes a 1,3-butadiyne derivative, which includes an aromatic group and / or an aliphatic hydrocarbon group, and can reduce the resistance of the electrode sheet, thereby reducing the impedance of the battery.

[0121] As can be seen from Examples 1 and 7-9, suitable heating conditions can ensure the conversion rate of the conductive agent precursor into the conductive agent, which further affects the resistance of the electrode sheet and the impedance of the full cell.

[0122] A comparison of Examples 1-9 with Comparative Example 1 shows that, with the same solid content, the viscosity of the cathode material in Examples 1-9 is lower than that in Comparative Example 1.

[0123] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A conductive agent precursor, characterized in that, It includes 1,3-butadiyne derivatives, which include aromatic groups and / or aliphatic hydrocarbon groups.

2. The conductive agent precursor according to claim 1, characterized in that, The aromatic group includes at least one selected from phenyl, thiophene, perylene, anthracene, and pyrene. And / or, the aliphatic hydrocarbon group includes C4~C 16 Aliphatic hydrocarbon groups.

3. The conductive agent precursor according to claim 1 or 2, characterized in that, The 1,3-butadiyne derivative also includes heteroatoms; Preferably, the heteroatom includes at least one of N, P, B, S, and Cl.

4. The conductive agent precursor according to any one of claims 1-3, characterized in that, The aromatic group includes a conjugated group with 14 or more carbon atoms.

5. The conductive agent precursor according to claim 4, characterized in that, The conjugated group includes at least one of perylene diimide, perylene diimide derivative, anthracene, anthracene derivative, pyrene, and pyrene derivative.

6. The conductive agent precursor according to any one of claims 1-5, characterized in that, The aromatic and / or aliphatic hydrocarbon groups include electron-donating and / or electron-withdrawing groups; Preferably, the electron-donating group includes alkyl and / or methoxy groups; And / or, the electron-withdrawing group includes at least one of halogen, cyano, and trifluoromethyl.

7. The conductive agent precursor according to any one of claims 1-6, characterized in that, The aromatic group and / or aliphatic hydrocarbon group also include polar groups; Preferably, the polar group includes at least one of phenol derivative group, carboxyl group, and amino group.

8. The conductive agent precursor according to any one of claims 1-7, characterized in that, The 1,3-butadiene derivatives include 1,3-butadiene derivatives containing aromatic groups and 1,3-butadiene derivatives containing aliphatic hydrocarbon groups. Preferably, the mass ratio of the 1,3-butadiene derivative containing an aromatic group to the 1,3-butadiene derivative containing an aliphatic hydrocarbon group is (5~100):

1.

9. An electrode sheet, characterized in that, It includes a current collector and an active material layer present on at least one side of the current collector, the active material layer including a conductive agent, the conductive agent being prepared from the conductive agent precursor according to any one of claims 1-8.

10. A battery, characterized in that, Includes the electrode sheet as described in claim 9.

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