Copper current collector material for suppressing zinc dendrite growth, preparation method thereof, and application

Abstract

The present disclosure provides a copper current collector for suppressing zinc dendrite growth, comprising: a copper substrate, and an artificial protrusion network welded to the copper substrate. The artificial protrusion network has an outwardly convex structure formed by nanowires, which is suitable for accumulating charges on the surface when energized and has the ability of electron transport. Among them, the charges accumulated on the surface of the artificial protrusion network are suitable for forming a microelectric field during the electrodeposition of metallic zinc to induce the uniform nucleation and growth of metallic zinc on the surface of the artificial protrusion network, thereby suppressing the growth of zinc dendrites. The present disclosure also provides a preparation method and application of the above copper current collector for suppressing zinc dendrite growth.

Description

Technical Field

[0001] The present disclosure belongs to the field of electrochemical energy storage, and particularly relates to a copper current collector material for inhibiting zinc dendrite growth, a preparation method thereof, and an application thereof. Background Art

[0002] Aqueous zinc metal batteries have advantages such as high specific capacity (Zn: 820 mAh g -1 / 5851 mAh mL -1 ), environmental friendliness, easy handling, and low cost, and show great application potential in the field of energy storage.

[0003] However, in actual use, aqueous zinc metal batteries have problems such as short service life. This is because there is an uncontrollable dendrite growth problem in the metal zinc negative electrode during the operation of the battery, resulting in a series of problems such as inactivation of the negative electrode active material, aggravated electrode deformation, and even in severe cases, dendrites piercing through the separator and causing internal short circuit of the battery.

[0004] In related technologies, improvements and attempts have been made in aspects such as battery structure and electrode liquid system configuration, but currently, the problems such as short battery life and poor cycle stability caused by dendrite growth in aqueous zinc metal batteries still cannot be properly solved. Therefore, exploring the problem of inhibiting dendrite growth of the zinc negative electrode during charge and discharge is one of the key technologies to promote the development of zinc metal batteries. Summary of the Invention

[0005] In view of this, to solve at least one technical problem in the related technologies and other aspects, the present disclosure proposes a copper current collector material for inhibiting zinc dendrite growth (hereinafter referred to as HC-Cu current collector), a preparation method thereof, and an application thereof. By constructing an artificial protrusion network with a microelectric field to induce uniform nucleation and growth of metallic zinc on the surface of the HC-Cu current collector, uncontrollable nucleation and growth of metallic zinc dendrites are avoided.

[0006] In one aspect of the present disclosure, a copper current collector for inhibiting zinc dendrite growth is proposed, including: a copper substrate, and an artificial protrusion network welded to the copper substrate. The artificial protrusion network has a convex structure formed by nanowires, is suitable for aggregating charges on the surface when energized, and has an electron transport ability. Among them, the charges aggregated on the surface of the artificial protrusion network are suitable for forming a microelectric field during electrodeposition of metallic zinc to induce uniform nucleation and growth of metallic zinc on the artificial protrusion network, thereby inhibiting zinc dendrite growth.

[0007] According to an embodiment of the present disclosure, the copper current collector further includes: zincophilic sites, and the zincophilic sites are deposited on the surfaces of the artificial protrusion network and the copper substrate to reduce the nucleation energy of metallic zinc.

[0008] According to an embodiment of the present disclosure, the material of the artificial protrusion network is a conductive nanowire material, wherein the diameter range of the conductive nanowire material is 10-500 nm.

[0009] According to an embodiment of the present disclosure, the loading amount of the artificial protrusion network on the surface of the copper substrate ranges from 1 to 50 mg cm -2 .

[0010] According to an embodiment of the present disclosure, the material of the zincophilic site is a zincophilic metal capable of reducing the nucleation energy of zinc metal, and the zincophilic metal includes one or more of Ag, Sn, Cu, In, and Sb.

[0011] In another aspect of the present disclosure, a method for preparing the above-mentioned copper current collector for inhibiting zinc dendrite growth is provided, including: uniformly dispersing a suspension of conductive nanowires on the surface of a copper substrate, and welding the conductive nanowires to the surface of the copper substrate by rapid heat treatment to obtain a copper current collector loaded with an artificial protrusion network.

[0012] According to an embodiment of the present disclosure, the method for preparing the above-mentioned copper current collector for inhibiting zinc dendrite growth further includes: immersing the copper current collector loaded with the artificial protrusion network in a zincophilic metal solution, and constructing zincophilic sites by electrochemical deposition to obtain a copper current collector for inhibiting zinc dendrite growth, wherein the zincophilic metal can reduce the nucleation energy of metallic zinc.

[0013] According to an embodiment of the present disclosure, the concentration range of the conductive nanowire suspension is 1-50 mg mL -1 ; the conditions for rapid heat treatment include: the temperature range is 1000-2000 °C, the treatment time range is 1-20 s, and the heat treatment atmosphere environment is one or more of air, nitrogen, argon, and hydrogen.

[0014] According to an embodiment of the present disclosure, the zincophilic metal solution includes one of silver chloride solution, tin chloride solution, copper chloride solution, indium chloride solution, and antimony chloride solution, the concentration range of the zincophilic metal solution is 0.01-5 M; the deposition capacity range of the electrochemical deposition is 0.01-100 mAh cm -2 , and the electrochemical deposition mode is one or more of constant current deposition, pulse deposition, and constant voltage deposition.

[0015] In another aspect of the present disclosure, an application of the above-mentioned copper current collector for inhibiting zinc dendrite growth as a negative electrode material in an aqueous zinc metal battery is provided.

[0016] According to the embodiments of the present disclosure, the present disclosure forms a stronger micro-electric field around the surface of the artificial protrusion network during the electrochemical process by constructing a stable artificial protrusion network, so as to induce the uniform nucleation, growth, and subsequent deposition of metallic zinc on the surface of the artificial protrusion network proposed by the present disclosure, avoiding uncontrollable nucleation, and thus effectively avoiding the generation of zinc dendrites. At the same time, the stable welding of the artificial protrusion network to the copper substrate plays a very important role in the stability and consistency of the copper current collector proposed by the present disclosure when used as an electrode. Description of the Drawings

[0017] Figure 1(a) is a scanning electron microscope image of the copper current collector material (hereinafter referred to as HC-Cu current collector) for suppressing the growth of zinc dendrites in the present disclosure;

[0018] Figure 1(b) is a partially enlarged scanning electron microscope image of the HC-Cu current collector in the present disclosure;

[0019] Figure 1(c) is a side view scanning electron microscope image of the HC-Cu current collector in the present disclosure;

[0020] Figure 2(a) is a schematic diagram of the metal zinc deposition process on a conventional copper current collector (hereinafter referred to as Cu current collector);

[0021] Figure 2(b) is a schematic diagram of the metal zinc deposition process on the HC-Cu current collector in the present disclosure;

[0022] Figure 3 is a schematic structural diagram of the copper current collector for suppressing the growth of zinc dendrites proposed by the present disclosure;

[0023] Figure 4(a) is a physical image of the HC-Cu current collector after high-temperature rapid heat treatment in the present disclosure after ultrasonic cleaning;

[0024] Figure 4(b) is a physical image of the HC-Cu current collector without high-temperature rapid heat treatment in the present disclosure after ultrasonic cleaning;

[0025] Figure 5(a) is a scanning electron microscope image of the surface morphology of the Cu current collector in the test example of the present disclosure when the surface capacity of zinc deposition is 0.0278 mAh cm -2 ;

[0026] Figure 5(b) is a scanning electron microscope image of the surface morphology of the Cu current collector in the test example of the present disclosure when the surface capacity of zinc deposition is 1 mAh cm -2 ;

[0027] Figure 5(c) is a scanning electron microscope image of the surface morphology of the Cu current collector in the test example of the present disclosure when the surface capacity of zinc deposition is 5 mAh cm -2 ;

[0028] Figure 5(d) is a scanning electron microscope image of the surface morphology of the HC-Cu current collector in the test example of the present disclosure when the surface capacity of zinc deposition is 0.0278 mAh cm -2 ;

[0029] Figure 5(e) is a scanning electron microscope image of the surface morphology of the HC-Cu current collector in the test example of the present disclosure when the surface capacity of zinc deposition is 1 mAh cm -2 ;

[0030] Figure 5(f) is a scanning electron microscope image of the surface morphology of the HC-Cu current collector in the test example of the present disclosure when the surface capacity of zinc deposition is 5 mAh cm -2 ;

[0031] Figure 6 is a comparison chart of the cycling performance of the semi-symmetric batteries (abbreviated as HC-Cu||Zn and Cu||Zn) assembled from metallic zinc and the HC-Cu current collector and the Cu current collector respectively in the test example of the present disclosure;

[0032] Figure 7 is a comparison chart of the cycling performance of the full batteries (abbreviated as HC-Cu||Br 2 and Cu||Br 2 ) assembled from bromine and the HC-Cu current collector and the Cu current collector respectively in the test example of the present disclosure;

[0033] Figure 8(a) is a morphology diagram of the Cu current collector for full battery construction in the test example of the present disclosure after pre-depositing 2 mAh of zinc metal;

[0034] Figure 8(b) is a morphology diagram of the HC-Cu current collector for full battery construction in the test example of the present disclosure after pre-depositing 2 mAh of zinc metal;

[0035] Figure 9 is a comparison chart of the cycling performance of the full batteries assembled from vanadium pentoxide and the pre-deposited HC-Cu current collector and the Cu current collector respectively in the test example of the present disclosure;

[0036] Figure 10(a) is a scanning electron microscope image of the surface morphology of the HC-Cu current collector with Sb as the zincophilic site in the semi-symmetric battery after cycling 20 times and then redepositing 5 mAh cm -2 ;

[0037] Figure 10(b) is a scanning electron microscope image of the surface morphology of the Cu current collector in the semi-symmetric battery after cycling 20 times and then redepositing 5 mAh cm -2 ; Detailed implementation manners

[0038] To make the objectives, technical solutions, and advantages of the present disclosure more clear and understandable, the following further elaborates on the present disclosure in detail with reference to specific embodiments and the accompanying drawings.

[0039] In the ranges disclosed in the present disclosure, the endpoints and any values of the ranges are not limited to the exact ranges or values. These ranges or values should be understood to include values close to these ranges or values. For numerical ranges, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values, they can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed in the present disclosure.

[0040] The terms used herein are merely for describing specific embodiments and are not intended to limit the present disclosure. The terms "including", "comprising", etc. used herein indicate the presence of the described features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0041] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used here should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0042] In an aqueous zinc metal battery, the deposition process of metallic zinc can be generally divided into three stages: nucleation, growth of crystal nuclei, and subsequent deposition of zinc metal. Among them, the uniformity of the nucleation process plays a crucial role in the uniformity of subsequent zinc deposition.

[0043] Figure 1(a) is a scanning electron microscope image of a copper current collector material (hereinafter referred to as the HC-Cu current collector) for suppressing zinc dendrite growth in the present disclosure.

[0044] Figure 1(b) is a partially enlarged scanning electron microscope image of the HC-Cu current collector in the present disclosure.

[0045] Figure 1(c) is a side view of the scanning electron microscope of the HC-Cu current collector in the present disclosure.

[0046] As Figure 1(a) to 1(c) shown, this artificial protrusion network has a higher curvature compared to the surface of a conventional planar copper current collector. For a charged conductor, at the protruding tip of the conductor surface (where the curvature is larger), the surface charge density is large, and at the relatively flat place on the surface (where the curvature is smaller), the surface charge density is small. Therefore, a large amount of surface charges accumulate on the surface of the artificial protrusion network constructed in the present disclosure, such that in the actual application process, a microelectric field stronger than that on the surface of a conventional Cu current collector is generated around the artificial protrusion network on the HC-Cu current collector proposed in the present disclosure.

[0047] Figure 2(a) is a schematic diagram of the metal zinc deposition process on a conventional copper current collector (hereinafter referred to as Cu current collector).

[0048] As shown in Figure 2(a), on the surface of a conventional Cu current collector, due to the influence of complex factors such as electrode polarization, ion diffusion, the interfacial layer, and the crystal growth and dissolution environment, it is easy to cause non-uniform nucleation of metal zinc, which is not conducive to subsequent uniform deposition.

[0049] Figure 2(b) is a schematic diagram of the metal zinc deposition process on the HC-Cu current collector in the present disclosure.

[0050] As shown in Figure 2(b), in the present disclosure, the morphology of the material that can be used as the negative current collector is designed, and a layer of artificial raised network is deposited and welded on the copper current collector. During the electrochemical process, zinc ions are attracted by the microelectric field on the surface of the artificial raised network for orderly and uniform nucleation growth and subsequent uniform deposition, avoiding the generation of uncontrollable metal zinc dendrites.

[0051] From Figure 2(a) , 2(b) comparison, the principle of zinc dendrite generation in the copper current collector proposed in the present disclosure is to improve the uniformity of metal zinc nucleation in the initial stage of deposition, which is beneficial to improving the uniformity of subsequent metal zinc deposition.

[0052] Figure 3 is a schematic structural diagram of the copper current collector for suppressing zinc dendrite growth proposed in the present disclosure.

[0053] In one aspect of the present disclosure, a copper current collector for suppressing zinc dendrite growth is proposed. As shown in Figure 1, it includes: a copper substrate; and an artificial raised network welded to the copper substrate. The artificial raised network has a convex structure formed by nanowires, which is suitable for accumulating charges on the surface when energized and has the ability of electron transport. Among them, the charges accumulated on the surface of the artificial raised network are suitable for forming a microelectric field to induce the uniform nucleation growth of metal zinc on the surface of the artificial raised network during the electro-deposition of metal zinc, thereby suppressing the growth of zinc dendrites.

[0054] According to the embodiments of the present disclosure, the present disclosure constructs a stable artificial raised network to form a microelectric field stronger than the relatively flat substrate surface around the surface of the artificial raised network during the electrochemical process, thereby inducing metal zinc to mainly perform uniform nucleation, growth, and subsequent deposition on the surface of the artificial raised network proposed in the present disclosure, avoiding uncontrollable nucleation, and thus effectively avoiding the generation of zinc dendrites. At the same time, the artificial raised network is stably welded to the copper substrate, which plays a very important role in the stability and consistency of the copper current collector proposed in the present disclosure when used as an electrode.

[0055] Figure 4(a) is a physical picture of the HC-Cu current collector after high-temperature rapid heat treatment in the present disclosure after ultrasonic cleaning.

[0056] Figure 4(b) is a physical diagram of the HC-Cu current collector without high-temperature rapid heat treatment in the present disclosure after ultrasonic cleaning.

[0057] As Figure 4(a) 、 4(b) shown, the high-temperature rapid heat treatment technology enables the artificial protrusion network to be welded to the copper substrate, playing a role in stabilizing the structure of the artificial protrusion network. After ultrasonic cleaning of two HC-Cu current collectors before and after high-temperature rapid heat treatment, it is found that in Figure 4(a), the surface morphology of the HC-Cu current collector after high-temperature rapid heat treatment still maintains good consistency after ultrasonic cleaning; in Figure 4(b), on the surface of the HC-Cu current collector without high-temperature rapid heat treatment, the artificial protrusion network has almost completely fallen off, showing poor structural stability. Therefore, the high-temperature rapid heat treatment technology ensures the structural stability and working stability of the HC-Cu current collector proposed in the present disclosure during the electrochemical process.

[0058] According to an embodiment of the present disclosure, the copper current collector further includes: zincophilic sites, which are deposited on the surface of the artificial protrusion network and the copper substrate to reduce the nucleation energy of metallic zinc.

[0059] According to an embodiment of the present disclosure, the zincophilic sites are formed by a class of metals that can reduce the nucleation energy of metallic zinc. Introducing zincophilic sites on the copper current collector proposed in the present disclosure is beneficial to the uniform deposition of metallic zinc, inhibits dendrite growth, and improves the electrochemical performance of the copper current collector.

[0060] According to an embodiment of the present disclosure, the material of the artificial protrusion network is a conductive nanowire material, wherein the diameter range of the conductive nanowire material is 10 - 500 nm, such as 10 nm, 20 nm, 50 nm, 80 nm, 100 nm, 250 nm, 400 nm, 500 nm, etc.

[0061] According to an embodiment of the present disclosure, after a large number of experimental tests by the applicant, the material of the artificial protrusion network can be a conductive metal material, preferably copper. At the same time, the applicant verified that the diameter range of the copper nanowire material has the best property of inducing the nucleation of metallic zinc within 100 - 500 nm.

[0062] According to an embodiment of the present disclosure, the loading amount range of the artificial protrusion network on the copper substrate surface is 1 - 50 mg cm -2 , for example, it can be set to 1 mg cm -2 , 5 mg cm -2 , 20 mg cm -2 , 35 mg cm -2 , 50 mg cm -2 etc.

[0063] According to an embodiment of the present disclosure, the zincophilic site is a zincophilic metal that can reduce the nucleation energy of zinc metal, and the zincophilic metal includes one or more of Ag, Sn, Cu, In, and Sb.

[0064] In another aspect of the present disclosure, a method for preparing the above-mentioned copper current collector for inhibiting zinc dendrite growth is provided, including: uniformly dispersing a suspension of conductive nanowires on the surface of a copper substrate, and welding the conductive nanowires to the surface of the copper substrate by rapid heat treatment to obtain a copper current collector loaded with an artificial protrusion network.

[0065] According to an embodiment of the present disclosure, the present disclosure constructs a stable structure on the surface of a conventional copper current collector using conductive nanowires as the material of the artificial protrusion network, which can effectively induce the uniform and stable nucleation growth and subsequent deposition of zinc ions on the surface of the current collector proposed in the present disclosure during the electrochemical process, improves the deposition morphology of metallic zinc, and enhances the battery cycle life with the current collector proposed in the present disclosure as the electrode.

[0066] According to an embodiment of the present disclosure, the method for preparing the above-mentioned copper current collector for inhibiting zinc dendrite growth further includes: immersing the copper current collector loaded with an artificial protrusion network in a zincophilic metal solution, and constructing zincophilic sites by electrochemical deposition to obtain a copper current collector for inhibiting zinc dendrite growth, wherein the zincophilic metal can reduce the nucleation energy of metallic zinc.

[0067] According to an embodiment of the present disclosure, the concentration range of the conductive nanowire suspension is 1-50 mg / mL -1 , for example, it can be selected as 1 mg / mL -1 , 20 mg / mL -1 , 35 mg / mL -1 , 40 mg / mL -1 , 50 mg / mL -1 etc. The conditions for rapid heat treatment include: the temperature range is 1000-2000 °C, for example, it can be selected as 1000 °C, 1200 °C, 1400 °C, 1600 °C, 1800 °C, 2000 °C, etc., and the treatment time range is 1-20 s, for example, it can be selected as 1 s, 5 s, 10 s, 15 s, 20 s, etc. The heat treatment atmosphere environment is one or more of air, nitrogen, argon, and hydrogen.

[0068] According to an embodiment of the present disclosure, the loading amount of the artificial protrusion network on the surface of the copper substrate is controlled by the concentration of the conductive nanowire suspension to construct the artificial protrusion network.

[0069] According to an embodiment of the present disclosure, the zincophilic metal solution includes one of a silver chloride solution, a tin chloride solution, a copper chloride solution, an indium chloride solution, and an antimony chloride solution. The concentration range of the zincophilic metal solution is 0.01 - 5 M (i.e., mol / L), and for example, it can be selected as 0.01 M, 0.15 M, 0.2 M, 0.25 M, 0.3 M, 0.45 M, 0.5 M, etc.; the deposition capacity range of the electrochemical deposition is 0.01 - 100 mAh cm -2 , for example, it can be selected as 0.01 mAh cm -2 , 5 mAh cm -2 , 30 mAh cm -2 , 50 mAh cm -2 , 78 mAh cm -2 , 100 mAh cm -2 . The electrochemical deposition mode is one or more of constant current deposition, pulse deposition, and constant voltage deposition.

[0070] In another aspect of the present disclosure, an application of the above copper current collector for suppressing zinc dendrite growth as a negative electrode material in an aqueous zinc metal battery is proposed.

[0071] According to an embodiment of the present disclosure, the present disclosure also proposes an application of assembling a full battery and a half battery with the above copper current collector for suppressing zinc dendrite growth as an electrode material.

[0072] It should be noted that the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments. Other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present disclosure without creative efforts all belong to the scope of protection of the present disclosure.

[0073] Example 1

[0074] S1: Prepare an artificial raised network

[0075] Under the condition that the temperature is 80 °C, add 20 mL of a Cu(NO 3 ) 2 solution with a concentration of 0.2 M to 670 mL of a NaOH solution with a concentration of 15 M and stir well. Then add 10 mL of ethylenediamine and 342 μL of hydrazine hydrate to the above solution and mix and stir for 80 min to obtain copper nanowires.

[0076] Wash and dry the copper nanowires, and then disperse them in an alcohol solution. Among them, the concentration of the copper nanowires in alcohol is 1.5 mg mL -1 .

[0077] S2: Prepare an HC-Cu current collector

[0078] The copper nanowires prepared in step S1 are used as artificial protrusions, and are uniformly deposited and dispersed on the surface of the copper foil by spraying and dispersion, so as to obtain a copper foil deposited with an artificial protrusion network, ensuring that the loading amount of the copper nanowires on the copper foil surface is 1-5 mg cm -2 .

[0079] Then, the copper foil deposited with the artificial protrusion network is rapidly heat-treated at a temperature of 1500 °C for 4 s to stably weld the artificial protrusion network to the copper foil, obtaining an HC-Cu current collector. Among them, the heat treatment atmosphere is argon.

[0080] Example 2

[0081] The HC-Cu current collector prepared in Example 1 is immersed in a mixed solution of 0.3 M SbCl 3 and 4 M H 2 SO 4 to construct zincophilic sites on the surface of the HC-Cu current collector through a pulsed current deposition mode, obtaining an HC-Cu current collector with Sb as the zincophilic site (hereinafter denoted as Sb@HC-Cu). Among them, the electrochemical deposition capacity is 0.02 mAh cm -2 .

[0082] Test Example 1

[0083] Under the condition of constant current deposition with a current density of 10 mA cm -2 , the zinc deposition morphologies of the HC-Cu current collector prepared in Example 1 of the present disclosure and the conventional Cu current collector were observed and compared under different deposition surface capacities.

[0084] Figures 5(a), (b), and (c) are scanning electron microscope images of the surface morphology of the Cu current collector in the test example of the present disclosure under the conditions of zinc deposition surface capacities of 0.0278 mAh cm -2 , 1 mAh cm -2 , and 5 mAh cm -2 .

[0085] Figures 5(d), (e), and (f) are scanning electron microscope images of the surface morphology of the HC-Cu current collector in the test example of the present disclosure under the conditions of zinc deposition surface capacities of 0.0278 mAh cm -2 , 1 mAh cm -2 , and 5 mAh cm -2 .

[0086] As shown in Figures 5(a)-(f), on the HC-Cu current collector proposed in the present disclosure, the nucleation, crystal nucleus growth, and subsequent deposition of metallic zinc always maintain good uniformity, while on the conventional Cu current collector, uneven nucleation and growth processes and uneven subsequent deposition are shown.

[0087] Test Example 2

[0088] The semi-symmetric batteries (hereinafter referred to as HC-Cu||Zn and Cu||Zn) assembled with metallic zinc and the HC-Cu current collector and the conventional Cu current collector prepared in Example 1 of the present disclosure were subjected to constant current charge and discharge cycle tests. Among them, the areal capacity during the test process was 1.77 mAh cm -2 , and the current density was 2C.

[0089] Figure 6 is a comparison chart of the cycle performance of the semi-symmetric batteries assembled with metallic zinc and the HC-Cu current collector and the Cu current collector in the test examples of the present disclosure;

[0090] As Figure 6 shown, the Cu||Zn semi-symmetric battery in the control group showed a short circuit phenomenon after cycling for about 500 h. Compared with the control group, the HC-Cu||Zn semi-symmetric battery assembled with the copper current collector proposed in the present disclosure ensured a stable cycle of nearly 3000 h, and the cycle life of the half-cell was increased by nearly 6 times.

[0091] Test Example 3

[0092] The full cells (hereinafter referred to as HC-Cu||Br 2 and Cu||Br 2 ) assembled with the bromine positive electrode and the HC-Cu current collector and the conventional Cu current collector prepared in Example 1 of the present disclosure were subjected to cycle tests. Among them, constant voltage charging was carried out at 1.9 V, the charging areal capacity was 2 mAh cm -2 , and constant current discharge was carried out to 0.5 V with a current density of 5C.

[0093] Figure 7 is a comparison chart of the cycle performance of the full cells assembled with bromine and the HC-Cu current collector and the Cu current collector in the test examples of the present disclosure.

[0094] As Figure 7 shown, the energy retention rate of the Cu||Br 2 full cell began to decline after cycling 300 times. The applicant analyzed that the reason for the decline in the energy retention rate of the Cu||Br 2 full cell was due to the inactivation of the negative electrode active material caused by the uneven deposition of metallic zinc during the working process. Compared with the control group, the HC-Cu||Br 2 full cell assembled with the copper current collector proposed in the present disclosure ensured stable operation for more than 900 cycles, and the cycle life of the battery was increased by more than 3 times.

[0095] Test Example 4

[0096] S1: Pre-deposit 2 mAh of metallic zinc on the HC-Cu current collector and the conventional Cu current collector prepared in Example 1 of the present disclosure.

[0097] Figure 8(a) is a topographical image of the Cu current collector used in the test example of the present disclosure after pre-depositing 2 mAh of zinc metal for full cell construction.

[0098] Figure 8(b) is a topographical image of the HC-Cu current collector used in the test example of the present disclosure after pre-depositing 2 mAh of zinc metal for full cell construction.

[0099] As shown in Figure 8(a) and Figure 8(b), compared with the conventional Cu current collector, the surface topography uniformity of the HC-Cu current collector prepared in the embodiment of the present disclosure has been significantly improved.

[0100] S2: Assemble the vanadium pentoxide cathode with the full cells (hereinafter referred to as Zn|HC-Cu||V 2 O 5 and Zn|Cu||V 2 O 5 ) obtained by respectively assembling the HC-Cu current collector and the conventional Cu current collector pre-deposited with 2 mAh of metallic zinc in step S1. Among them, the test condition is constant current charge and discharge test.

[0101] Figure 9 is a comparison chart of the cycling performance of the full cells obtained by assembling vanadium pentoxide with the pre-deposited HC-Cu current collector and Cu current collector in the test example of the present disclosure.

[0102] As Figure 9 shown, the Zn|HC-Cu||V 2 O 5 cell assembled with the copper current collector proposed in the present disclosure as the electrode material has better cycling performance than Zn|Cu||V 2 O 5 . Among them, after 1500 cycles, the capacity retained by the Zn|HC-Cu||V 2 O 5 cell is nearly twice that of the Zn|Cu||V 2 O 5 cell.

[0103] Test Example 5

[0104] Assemble the Sb@HC-Cu current collector and the conventional Cu current collector prepared in Example 2 of the present disclosure with metallic zinc foil respectively to obtain semi-symmetric electrodes (hereinafter referred to as Sb@HC-Cu||Zn and Cu||Zn) for cycling tests. After 20 cycles, perform 5 mAh cm -2Deposition was carried out, and the surface morphology of the current collector after deposition was characterized by SEM. Among them, the areal capacity during the test process was 5 mAh cm -2 , and the charge quantity was 1 C.

[0105] Figure 10(a) is a scanning electron microscope image of the morphology of the Sb@HC-Cu current collector after cycling 20 times in a semi-symmetric battery and then redepositing 5 mAh cm -2 .

[0106] Figure 10(b) is a scanning electron microscope image of the morphology of the Cu current collector after cycling 20 times in a semi-symmetric battery and then redepositing 5 mAh cm -2 .

[0107] As shown in Figure 10(a) and Figure 10(b), zinc metal was uniformly deposited on the Sb@HC-Cu current collector, while the deposition uniformity on the conventional copper current collector was very poor.

[0108] The specific embodiments described above further elaborate on the purpose, technical solutions, and beneficial effects of the present disclosure. It should be understood that the above are only specific embodiments of the present disclosure and are not used to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present disclosure shall be included within the protection scope of the present disclosure.

Claims

1. A copper current collector for inhibiting zinc dendrite growth, comprising: a copper substrate; and an artificial protrusion network welded to the copper substrate, the artificial protrusion network having a convex structure formed by nanowires, suitable for accumulating charges on the surface when energized, having electron transport ability, and the material of the artificial protrusion network being a conductive nanowire material, wherein the diameter range of the conductive nanowire material is 10 - 500 nm; wherein, the charges accumulated on the surface of the artificial protrusion network are suitable for forming a micro - electric field during the electrodeposition of metallic zinc to induce the uniform nucleation and growth of metallic zinc on the surface of the artificial protrusion network, thereby inhibiting the growth of zinc dendrites; the copper current collector further includes zinc - philic sites deposited on the surfaces of the artificial protrusion network and the copper substrate to reduce the nucleation energy of metallic zinc, and the material of the zinc - philic sites is a zinc - philic metal capable of reducing the nucleation energy of zinc metal.

2. The copper current collector according to claim 1, wherein, The loading amount of the artificial protrusion network on the surface of the copper substrate ranges from 1 to 50 mg cm -2 .

3. The copper current collector according to claim 1, wherein, the zinc - philic metal includes one or more of Ag, Sn, Cu, In, and Sb.

4. A method for preparing a copper current collector for inhibiting zinc dendrite growth as described in any one of claims 1 to 3, comprising: uniformly dispersing a suspension of conductive nanowires on the surface of a copper substrate, and welding the conductive nanowires to the surface of the copper substrate through rapid heat treatment to obtain a copper current collector loaded with an artificial protrusion network.

5. The method according to claim 4, further comprising: immersing the copper current collector loaded with the artificial protrusion network into a zinc - philic metal solution, and constructing zinc - philic sites through electrochemical deposition to obtain a copper current collector for inhibiting zinc dendrite growth, wherein the zinc - philic metal can reduce the nucleation energy of metallic zinc.

6. The method according to claim 4, wherein, The concentration range of the conductive nanowire suspension is 1 to 50 mg / mL -1 ; the conditions of the rapid heat treatment include: the temperature range is 1000 - 2000 °C, the treatment time range is 1 - 20 s, and the heat treatment atmosphere environment is one or more of air, nitrogen, argon, and hydrogen.

7. The method according to claim 5, wherein, the zinc - philic metal solution includes one of silver chloride solution, tin chloride solution, copper chloride solution, indium chloride solution, and antimony chloride solution, and the concentration range of the zinc - philic metal solution is 0.01 - 5 M; The deposition capacity of the electrochemical deposition ranges from 0.01 to 100 mAh cm -2 , and the electrochemical deposition mode is one or more of constant current deposition, pulse deposition, and constant voltage deposition.

8. An application of a copper current collector for inhibiting zinc dendrite growth as described in any one of claims 1 to 3 as a negative electrode material in an aqueous zinc - metal battery.

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