A lithium / sodium ion battery electrode structure, preparation method and application

Abstract

A lithium / sodium ion battery electrode structure, preparation method and application belong to the field of chemical power source technology. The specific scheme is: a lithium / sodium ion battery electrode structure, including a plurality of active material areas, a plurality of metal ion source storage areas and a plastic-metal composite current collector, wherein the plurality of active material areas and the plurality of metal ion source storage areas are alternately arranged on the surface of the plastic-metal composite current collector, and an insulating area is arranged between any active material area and an adjacent metal ion source storage area; the active material area is coated with an active material, and the metal ion source storage area is evaporated with a metal ion source. The present invention arranges the negative electrode / positive electrode and the metal ion source electrode on the same plane through the partition structure design of the plastic-metal composite current collector and realizes the electronic insulation of the negative electrode / positive electrode and the metal ion source. The novel electrode structure provides a solution for high specific energy and long life lithium / sodium ion batteries.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical power sources, and in particular relates to a lithium / sodium ion battery electrode structure, a preparation method and an application thereof. Background Art

[0002] Lithium-ion batteries have technical advantages such as high energy density, long cycle life, and fast charge and discharge rates. They are widely used in portable electronic devices, drones, and electric vehicles. In recent years, the market's requirements for the energy density of lithium-ion batteries have gradually increased, and traditional graphite negative electrodes can no longer meet the demand. Compared with graphite negative electrodes, silicon-based negative electrodes and lithium metal negative electrodes have ultra-high theoretical capacity, and have gradually become the research focus of enterprises and universities. However, the silicon-based negative electrode has huge volume changes during the cycle process. The repeated expansion and contraction process causes the continuous fragmentation and reconstruction of the SEI film, resulting in continuous consumption of active lithium at the positive electrode, and the battery capacity decays rapidly. Traditional lithium replenishment methods can improve the battery's first coulomb efficiency, but cannot solve the problem of active lithium loss during the cycle; lithium metal negative electrodes have the problem of dendrite growth, and lithium metal batteries have high safety risks. Recently, researchers have introduced lithium metal electrodes (lithium sources) into silicon-based negative electrode lithium-ion batteries and used diode units to connect silicon-based negative electrodes and lithium negative electrodes to construct an "intelligent" lithium compensation circuit, hoping to achieve the lithium compensation function of the battery throughout its life cycle (Intelligent dual-anode strategy for high-performance lithium-ion batteries, Device, 2024, 100501). However, the lithium metal electrode is set on the outside of the stacked battery. The lithium ions dissolved from the lithium metal electrode need to diffuse through the electrode edge to the silicon-based negative electrode and positive electrode, which greatly reduces the lithium compensation rate. When the electrode size is large, there is a large difference between the lithium compensation at the electrode edge and inside the electrode. Excessive compensation at the electrode edge can easily cause charging and lithium deposition, which in turn leads to battery short circuit failure. In addition, the stacking of lithium metal electrodes and silicon-based negative electrodes has a large edge effect, and the lithium metal electrode will undergo non-uniform electrochemical dissolution. The rapid dissolution process of the lithium metal electrode edge can easily produce broken lithium particles, and the lithium particles free in the battery can easily cause the battery to short circuit and fail. Similarly, the sodium replenishment process of sodium ion batteries also has the above technical problems. Summary of the invention

[0003] In order to solve the technical problems of slow metal ion compensation rate, poor compensation uniformity and non-uniform dissolution of metal ion source in laminated battery system, the present invention provides a lithium / sodium ion battery electrode structure, preparation method and application.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A lithium / sodium ion battery electrode structure comprises a plurality of active material areas, a plurality of metal ion source storage areas and a plastic-metal composite current collector, wherein the plurality of active material areas and the plurality of metal ion source storage areas are alternately arranged on the surface of the plastic-metal composite current collector, and an insulating area exists between any active material area and an adjacent metal ion source storage area; the active material area is coated with active material, and the metal ion source storage area is evaporated with a metal ion source.

[0006] Furthermore, in the electrode structure of a lithium-ion battery, the metal ion source is lithium metal or a lithium-rich alloy; in the electrode structure of a sodium-ion battery, the metal ion source is sodium metal or a sodium-rich alloy.

[0007] Preferably, the mass fraction of lithium in the lithium-rich alloy is greater than 80%, and the lithium-rich alloy is a lithium-indium alloy, a lithium-magnesium alloy, a lithium-antimony alloy, a lithium-aluminum alloy, a lithium-tin alloy, a lithium-silver alloy or a lithium-zinc alloy.

[0008] Preferably, the mass fraction of sodium in the sodium-rich alloy is greater than 80%, and the sodium-rich alloy is a sodium-rich sodium-antimony alloy, a sodium-silver alloy, a sodium-gold alloy, a sodium-indium alloy or a sodium-tin alloy.

[0009] Furthermore, the plastic-metal composite current collector includes a plastic matrix and a plurality of metal current collectors, each active material region and each metal ion source storage region corresponds to a metal current collector, two adjacent metal current collectors are insulated from each other, and all metal current collectors are fixedly arranged on the plastic matrix.

[0010] Preferably, there is a gap between two adjacent metal current collectors, exposing the plastic matrix to form an insulating area.

[0011] Furthermore, in the electrode structure of a lithium-ion battery, the metal current collector corresponding to the positive electrode active material is aluminum foil, the metal current collector corresponding to the negative electrode active material is copper foil, and the metal current collector corresponding to the metal ion source is copper foil; in the electrode structure of a sodium-ion battery, the metal current collectors corresponding to the positive electrode active material, the negative electrode active material and the metal ion source are all aluminum foil.

[0012] Furthermore, in the same electrode structure, the metal current collectors corresponding to all active material regions are connected in parallel, and the metal current collectors corresponding to all metal ion source storage regions are connected in parallel.

[0013] All active material areas and all metal ion source storage areas have the same width as the plastic-metal composite current collector, and the width ratio of a single active material area and a single metal ion source storage area is (1-20): 1. The specific size is set according to actual needs.

[0014] A method for preparing a lithium / sodium ion battery electrode structure comprises the following steps:

[0015] Step 1: using a plasma cleaning method to perform surface treatment on the plastic substrate to obtain a surface-modified plastic substrate;

[0016] Step 2: Vapor-depositing a plurality of metal films as metal current collectors on the surface of the modified plastic substrate in different regions to obtain a plastic-metal composite current collector, wherein two adjacent metal current collectors are insulated from each other;

[0017] Step 3: coating the active material on the metal current collector corresponding to the active material area;

[0018] Step 4: evaporating a metal ion source film on the metal current collector corresponding to the metal ion source storage area;

[0019] Step 5: connecting the metal current collectors corresponding to all active material regions on the same plastic-metal composite current collector in parallel through wires;

[0020] Step 6: Connect the metal current collectors corresponding to all metal ion source storage areas on the same plastic-metal composite current collector in parallel through wires.

[0021] Furthermore, in step 2, in the lithium-ion battery electrode structure, the metal current collector corresponding to the positive electrode active material is aluminum foil, the metal current collector corresponding to the negative electrode active material is copper, and the metal current collector corresponding to the metal ion source storage area is copper foil; in the sodium-ion battery electrode structure, the metal current collectors corresponding to the positive electrode active material, the negative electrode active material and the metal ion source are all aluminum foil.

[0022] Furthermore, in step three, the coating method is wet coating, dry coating or 3D printing.

[0023] An application of the lithium / sodium ion battery electrode structure, wherein the lithium / sodium ion battery electrode structure is applied to a lithium ion battery or a sodium ion battery, wherein the positive electrode and the negative electrode of the lithium ion battery or the sodium ion battery have the same electrode structure.

[0024] Furthermore, in a lithium-ion battery or a sodium-ion battery, the metal current collectors corresponding to all metal ion source storage areas in the positive electrode and the metal current collectors corresponding to all metal ion source storage areas in the negative electrode are connected in parallel and lead out to the pole lug I, the metal current collectors corresponding to all negative electrode active material areas are connected in parallel to lead out to the pole lug II, and the metal current collectors corresponding to all positive electrode active material areas are connected in parallel to lead out to the pole lug III; when it is necessary to replenish active ions to the battery, the pole lug I is connected to the pole lug II / pole lug III through an external circuit to form a discharge circuit to achieve intermittent replenishment of active ions; or the pole lug I is connected in series with the pole lug II through a diode to achieve continuous replenishment of active ions.

[0025] Furthermore, the anode (+) of the diode is electrically connected to the tab II, and the cathode (-) is electrically connected to the tab I.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] Compared with the lithium / sodium ion battery system with an external metal ion source, the novel lithium / sodium ion battery electrode structure of the present invention can realize the uniform dissolution of the metal ion source and the rapid diffusion of the dissolved metal ions, and significantly improve the compensation efficiency and compensation uniformity of the metal ions in the lithium / sodium ion battery; in addition, the partitioned arrangement of the plastic-metal composite current collector can realize the electronic insulation between the active material area and the metal ion source electrode on the same composite electrode, and avoid the internal short circuit of the same composite electrode. The plastic-metal composite current collector not only has high structural stability, but also can significantly improve the energy density of the lithium / sodium ion battery; in summary, the present invention provides an innovative structural solution for the realization of high specific energy and long life lithium ion batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the structure of the present invention;

[0029] In the figure, 1 is a plastic-metal composite current collector, 2 is an active material area, 3 is a metal ion source storage area, and 4 is an insulating area. DETAILED DESCRIPTION

[0030] The technical solution of the present invention will be clearly and completely described below in conjunction with the drawings and embodiments. Obviously, the described embodiments are only part of the embodiments of the invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0031] Embodiment 1:

[0032] A lithium-ion battery electrode structure comprises 10 active material regions 2, 11 metal ion source storage regions 3 and a plastic-metal composite current collector 1, wherein the 10 active material regions 2 and the 11 metal ion source storage regions 3 are alternately arranged on the surface of the plastic-metal composite current collector 1, and an insulating region 4 exists between any active material region 2 and an adjacent metal ion source storage region 3; the active material region 2 is coated with an active material, and the metal ion source storage region 3 is evaporated with a metal ion source.

[0033] Furthermore, in the positive electrode structure, the active material is a commercial high nickel ternary (LiNi 0.8 Co 0.1 Mn 0.1 O2, NCM811, theoretical capacity 200 mAh / g); in the negative electrode structure, the active material is commercial SiOx (Theoretical capacity 1400mAh / g); the metal ion source is lithium metal.

[0034] Furthermore, the plastic-metal composite current collector 1 includes a plastic matrix and 21 metal current collectors, each active material area 2 and each metal ion source storage area 3 corresponds to a metal current collector, two adjacent metal current collectors are insulated from each other, and all metal current collectors are fixedly arranged on the plastic matrix.

[0035] Furthermore, the metal current collector corresponding to the positive electrode active material is aluminum foil, the metal current collector corresponding to the negative electrode active material is copper foil, and the metal current collector corresponding to the metal ion source is copper foil.

[0036] Furthermore, in the same electrode structure, the metal current collectors corresponding to all active material regions 2 are connected in parallel, and the metal current collectors corresponding to all metal ion source storage regions 3 are connected in parallel.

[0037] Preferably, the lengths of all active material regions and all metal ion source storage regions are the same as the width of the plastic-metal composite current collector, and the width ratio of a single active material region and a single metal ion source storage region is 5:1.

[0038] Example 2

[0039] A method for preparing the lithium ion battery electrode structure according to embodiment 1 comprises the following steps:

[0040] Step 1: using a plasma cleaning method to perform surface treatment on the plastic substrate to obtain a surface-modified plastic substrate;

[0041] Step 2: evaporating 21 metal films as metal current collectors in different regions on the surface of the modified plastic substrate to obtain a plastic-metal composite current collector 1, with insulation between two adjacent metal current collectors;

[0042] Step 3: wet-coat the active material on the metal current collector corresponding to the active material area 2, and the positive and negative electrode n / p ratio is 1.08;

[0043] Step 4: evaporating a lithium metal film on the metal current collector corresponding to the metal ion source storage area 3;

[0044] Step 5: connecting the metal current collectors corresponding to all active material regions 2 on the same plastic-metal composite current collector 1 in parallel through wires;

[0045] Step 6: Connect the metal current collectors corresponding to all the metal ion source storage areas 3 on the same plastic-metal composite current collector 1 in parallel through wires.

[0046] Furthermore, in step 2, in the lithium-ion battery electrode structure, the metal current collector corresponding to the positive electrode active material is aluminum foil, the metal current collector corresponding to the negative electrode active material is copper, and the metal current collector corresponding to the metal ion source storage area is copper foil.

[0047] Example 3

[0048] An application of the lithium-ion battery electrode structure described in Example 1, wherein the lithium-ion battery electrode structure is applied to a lithium-ion battery, and the positive electrode and the negative electrode have the same electrode structure.

[0049] The metal current collectors corresponding to all metal ion source storage areas in the positive electrode and the metal current collectors corresponding to all metal ion source storage areas in the negative electrode are connected in parallel and lead out to the pole lug I, the metal current collectors corresponding to all negative electrode active material areas are connected in parallel to lead out to the pole lug II, and the metal current collectors corresponding to all positive electrode active material areas are connected in parallel to lead out to the pole lug III.

[0050] After every 20 cycles of the 5Ah laminated soft-pack battery prepared with the above electrode structure, the pole tab I is connected to the pole tab II through an external circuit to form a discharge circuit to achieve intermittent replenishment of active lithium ions. After intermittent active lithium compensation, the capacity retention rate reaches 95% after 500 cycles at 1C rate at room temperature in the voltage range of 3.0-4.3V; after disassembling the battery, no lithium deposition was found on the negative electrode surface, and the lithium replenishment electrode dissolved evenly.

[0051] Example 4

[0052] A sodium ion battery electrode structure comprises five active material regions 2, six metal ion source storage regions 3 and a plastic-metal composite current collector 1, wherein the five active material regions 2 and the six metal ion source storage regions 3 are alternately arranged on the surface of the plastic-metal composite current collector 1, and an insulating region 4 exists between any active material region 2 and an adjacent metal ion source storage region 3; the active material region 2 is coated with an active material, and the metal ion source storage region 3 is evaporated with a metal ion source.

[0053] Furthermore, in the positive electrode structure, the active material is commercial sodium vanadium phosphate; in the negative electrode structure, the active material is commercial hard carbon; and the metal ion source is sodium metal.

[0054] Furthermore, the plastic-metal composite current collector 1 includes a plastic matrix and 11 metal current collectors, each active material area 2 and each metal ion source storage area 3 corresponds to a metal current collector, two adjacent metal current collectors are insulated from each other, and all metal current collectors are fixedly arranged on the plastic matrix.

[0055] Furthermore, the metal current collectors corresponding to the positive electrode active material, the negative electrode active material and the metal ion source are all aluminum foils.

[0056] Furthermore, in the same electrode structure, the metal current collectors corresponding to all active material regions 2 are connected in parallel, and the metal current collectors corresponding to all metal ion source storage regions 3 are connected in parallel.

[0057] Preferably, the lengths of all active material regions and all metal ion source storage regions are the same as the width of the plastic-metal composite current collector, and the width ratio of a single active material region and a single metal ion source storage region is 10:1.

[0058] Embodiment 5:

[0059] A method for preparing the sodium ion battery electrode structure according to embodiment 4 comprises the following steps:

[0060] Step 1: using a plasma cleaning method to perform surface treatment on the plastic substrate to obtain a surface-modified plastic substrate;

[0061] Step 2: 11 metal films are deposited on the surface of the modified plastic substrate in different regions as metal current collectors to obtain a plastic-metal composite current collector 1, and two adjacent metal current collectors are insulated from each other;

[0062] Step 3: dry-coating the active material on the metal current collector corresponding to the active material area 2;

[0063] Step 4: Vapor-depositing a sodium metal film on the metal current collector corresponding to the metal ion source storage area 3;

[0064] Step 5: connecting the metal current collectors corresponding to all active material regions 2 on the same plastic-metal composite current collector 1 in parallel through wires;

[0065] Step 6: Connect the metal current collectors corresponding to all the metal ion source storage areas 3 on the same plastic-metal composite current collector 1 in parallel through wires.

[0066] Furthermore, in step 2, the metal current collectors corresponding to the positive electrode active material, the negative electrode active material and the metal ion source are all aluminum foils.

[0067] Embodiment 6:

[0068] An application of the sodium ion battery electrode structure described in Example 4, wherein the sodium ion battery electrode structure is applied to a sodium ion battery, and the electrode structures of the positive electrode and the negative electrode are the same.

[0069] The metal current collectors corresponding to all metal ion source storage areas in the positive electrode and the metal current collectors corresponding to all metal ion source storage areas in the negative electrode are connected in parallel and lead out to the pole ear I, the metal current collectors corresponding to all negative electrode active material areas are connected in parallel to lead out to the pole ear II, and the metal current collectors corresponding to all positive electrode active material areas are connected in parallel to lead out to the pole ear III; the pole ear I is electrically connected to the pole ear II through a diode (the forward conduction voltage is 0.7V) to achieve continuous replenishment of active ions.

[0070] The 4Ah laminated soft-pack battery prepared with the above electrode structure, after continuous compensation of active sodium ions, maintained a capacity retention rate of 93% after 200 cycles at a rate of 1C at room temperature in the voltage range of 2.5-3.8V; after disassembling the battery, no sodium precipitation was found on the surface of the negative electrode, and the sodium-supplemented electrode dissolved evenly.

[0071] Example 7

[0072] The difference between this embodiment and embodiment 1 is that the metal ion source is a lithium-indium alloy with a lithium content of 90%, the width ratio of a single active material area and a single metal ion source storage area is 15:1, and the rest is the same as embodiment 1.

[0073] The preparation method and application of the lithium ion battery electrode structure in this embodiment are the same as those in Embodiments 2 and 3.

[0074] After every 20 cycles of the 5Ah laminated soft-pack battery prepared with the above electrode structure, the pole tab I is connected to the pole tab II through an external circuit to form a discharge circuit to achieve intermittent replenishment of active lithium ions. After intermittent active lithium compensation, the capacity retention rate reaches 92% after 500 cycles at 1C rate at room temperature in the voltage range of 3.0-4.3V; after disassembling the battery, no lithium deposition was found on the negative electrode surface, and the lithium replenishment electrode dissolved evenly.

[0075] Example 8

[0076] The difference between this embodiment and embodiment 4 is that the metal ion source is a sodium-antimony alloy with a sodium metal content of 85%, the width ratio of a single active material area and a single metal ion source storage area is 8:1, and the rest is the same as embodiment 4.

[0077] The preparation method and application of the sodium ion battery electrode structure in this embodiment are the same as those in Examples 5 and 6.

[0078] The 4Ah laminated soft-pack battery prepared with the above electrode structure, after continuous compensation of active sodium ions, has a capacity retention rate of 90% after 200 cycles at a rate of 1C at room temperature in the voltage range of 2.5-3.8V; after disassembling the battery, no sodium precipitation was found on the surface of the negative electrode, and the sodium-supplemented electrode dissolved evenly.

[0079] Example 9

[0080] A lithium-ion battery comprises a positive electrode and a negative electrode, wherein the active material in the positive electrode is a commercial high-nickel ternary positive electrode NCM811, the positive electrode current collector is an aluminum foil, and the active material in the negative electrode is a commercial SiO x (Theoretical capacity 1400 mAh / g), the negative electrode current collector is copper foil. The size of the positive electrode is the same as the total size of all positive electrode active material areas in Example 3, and the size of the negative electrode is the same as the total size of all negative electrode active material areas in Example 3.

[0081] The capacity retention rate of the 5Ah laminated soft-pack battery prepared with the above electrode structure is only 53% after 200 cycles at 1C rate at room temperature in the voltage range of 3.0-4.3V.

[0082] Example 10

[0083] A lithium-ion battery with a lithium-supplementing electrode, comprising a positive electrode sheet, a negative electrode sheet and a lithium-supplementing electrode sheet, wherein the positive electrode active material in the positive electrode sheet is a commercial high-nickel ternary positive electrode NCM811, the positive electrode current collector is an aluminum foil, and the active material in the negative electrode is a commercial SiO x (Theoretical capacity 1400 mAh / g), the negative electrode current collector is copper foil, the lithium supplement electrode sheet is lithium metal, the positive electrode sheet and the negative electrode sheet are separated by a diaphragm, and the lithium supplement electrode sheet is arranged on one side of the negative electrode sheet and separated from the negative electrode sheet by the diaphragm. The size of the positive electrode sheet is the same as the total size of all positive electrode active material areas in Example 3, the size of the negative electrode sheet is the same as the total size of all negative electrode active material areas in Example 3, and the size of the lithium supplement electrode sheet is the same as the total size of all metal ion source storage areas in Example 3.

[0084] After every 20 cycles of the 5Ah laminated soft-pack battery prepared with the above electrode structure, the lithium-replenishing electrode sheet was electrically connected to the negative electrode sheet through an external circuit for lithium replenishment. After intermittent active lithium compensation, the capacity dropped sharply after 120 cycles at 1C rate at room temperature in the voltage range of 3.0-4.3V. Disassembly revealed that obvious lithium deposition occurred at the edge of the negative electrode, causing the battery to short-circuit and fail; in addition, only the edge of the lithium-replenishing electrode sheet was electrochemically dissolved, and a large amount of lithium debris appeared on the surface of the lithium-replenishing electrode sheet; the above results show that this structure is not suitable for active lithium compensation during the cycling of large-capacity batteries.

[0085] Embodiment 11

[0086] A sodium ion battery comprises a positive electrode and a negative electrode, wherein the active material in the positive electrode is sodium vanadium phosphate, and the positive electrode current collector is aluminum foil, and the active material in the negative electrode is hard carbon, and the negative electrode current collector is aluminum foil. The size of the positive electrode is the same as the total size of all positive electrode active material areas in Example 6, and the size of the negative electrode is the same as the total size of all negative electrode active material areas in Example 6.

[0087] The capacity retention rate of the 4Ah laminated soft-pack battery prepared with the above electrode structure is only 70% after 200 cycles at 1C rate at room temperature in the voltage range of 2.5-3.8V.

[0088] Example 12

[0089] A sodium ion battery with a sodium supplement electrode, comprising a positive electrode sheet, a negative electrode sheet and a sodium supplement electrode sheet, wherein the active material in the positive electrode sheet is sodium vanadium phosphate, the positive electrode current collector is aluminum foil, the active material in the negative electrode sheet is hard carbon, the negative electrode current collector is aluminum foil, the sodium supplement electrode sheet is a sodium antimony alloy with a content of 85%, the positive electrode sheet and the negative electrode sheet are separated by a diaphragm, the sodium supplement electrode sheet is arranged on one side of the negative electrode sheet and is separated from the negative electrode sheet by the diaphragm, and the sodium supplement electrode sheet is electrically connected to the negative electrode sheet through a diode (forward conduction voltage is 0.7V). The size of the positive electrode sheet is the same as the total size of all positive electrode active material areas in Example 8, the size of the negative electrode sheet is the same as the total size of all negative electrode active material areas in Example 8, and the size of the sodium supplement electrode sheet is the same as the total size of all metal ion source storage areas in Example 8.

[0090] The 4Ah laminated soft-pack battery prepared with the above electrode structure, after continuous compensation of active sodium ions, suffered short circuit failure after cycling 50 times at a rate of 1C in the voltage range of 2.5-3.8V at room temperature. When the battery was disassembled, it was found that obvious sodium precipitation occurred at the edge of the negative electrode, and the sodium-compensated electrode also underwent non-uniform dissolution. The above results indicate that this structure is not suitable for active sodium compensation during the cycling process of large-capacity batteries.

[0091] The present invention arranges the negative electrode / positive electrode and the metal ion source electrode in the same plane through the structural design of the plastic-metal composite current collector, and realizes the electronic insulation between the negative electrode / positive electrode and the metal ion source by utilizing the partition structure of the plastic-metal composite current collector. The novel electrode structure can significantly improve the dissolution uniformity of the metal ion source electrode, shorten the diffusion distance of the dissolved metal ions, improve the lithium / sodium compensation rate and the lithium / sodium compensation uniformity, and provide a solution for high specific energy and long life lithium / sodium ion batteries.

[0092] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A lithium / sodium ion battery electrode structure, characterized in that: The invention comprises a plurality of active material regions (2), a plurality of metal ion source storage regions (3) and a plastic-metal composite current collector (1), wherein the plurality of active material regions (2) and the plurality of metal ion source storage regions (3) are alternately arranged on the surface of the plastic-metal composite current collector (1), and an insulating region (4) exists between any active material region (2) and an adjacent metal ion source storage region (3); the active material region (2) is coated with active material, and the metal ion source storage region (3) is evaporated with a metal ion source; the plastic-metal composite current collector (1) comprises a plastic substrate and a plurality of metal current collectors, each active material region (2) and each metal ion source storage region (3) corresponds to a metal current collector, two adjacent metal current collectors are insulated from each other, and all metal current collectors are fixedly arranged on the plastic substrate; in the same electrode structure, the metal current collectors corresponding to all active material regions (2) are connected in parallel, and the metal current collectors corresponding to all metal ion source storage regions (3) are connected in parallel.

2. A lithium / sodium ion battery electrode structure according to claim 1, characterized in that: In the electrode structure of lithium-ion batteries, the metal ion source is lithium metal or lithium-rich alloys; in the electrode structure of sodium-ion batteries, the metal ion source is sodium metal or sodium-rich alloys.

3. A lithium / sodium ion battery electrode structure according to claim 1, characterized in that: In the electrode structure of lithium-ion batteries, the metal current collector corresponding to the positive active material is aluminum foil, the metal current collector corresponding to the negative active material is copper foil, and the metal current collector corresponding to the metal ion source is copper foil; in the electrode structure of sodium-ion batteries, the metal current collectors corresponding to the positive active material, negative active material and metal ion source are all aluminum foil.

4. A lithium / sodium ion battery electrode structure according to claim 1, characterized in that: The lengths of all active material regions (2) and all metal ion source storage regions (3) are the same as the width of the plastic-metal composite current collector (1), and the width ratio of a single active material region (2) and a single metal ion source storage region (3) is (1-20):

1.

5. A method for preparing a lithium / sodium ion battery electrode structure according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: using a plasma cleaning method to perform surface treatment on the plastic substrate to obtain a surface-modified plastic substrate; Step 2: Vapor-depositing a plurality of metal films as metal current collectors on the surface of the modified plastic substrate in different regions to obtain a plastic-metal composite current collector (1), wherein two adjacent metal current collectors are insulated from each other; Step 3: coating the active material on the metal current collector corresponding to the active material area (2); Step 4: evaporating a metal ion source film on the metal current collector corresponding to the metal ion source storage area (3); Step 5: connecting the metal current collectors corresponding to all active material regions (2) on the same plastic-metal composite current collector (1) in parallel via wires; Step 6: Connect the metal current collectors corresponding to all the metal ion source storage areas (3) on the same plastic-metal composite current collector (1) in parallel through wires.

6. The preparation method according to claim 5, characterized in that: In step three, the coating method is wet coating, dry coating or 3D printing.

7. An application of the lithium / sodium ion battery electrode structure according to any one of claims 1 to 4, characterized in that: The lithium / sodium ion battery electrode structure is applied to a lithium ion battery or a sodium ion battery. In the lithium ion battery or the sodium ion battery, the electrode structures of the positive electrode and the negative electrode are the same.

8. The use according to claim 7, characterized in that: In a lithium-ion battery or a sodium-ion battery, the metal current collectors corresponding to all metal ion source storage areas in the positive electrode and the metal current collectors corresponding to all metal ion source storage areas in the negative electrode are connected in parallel and lead out to the pole lug I, the metal current collectors corresponding to all negative electrode active material areas are connected in parallel to lead out to the pole lug II, and the metal current collectors corresponding to all positive electrode active material areas are connected in parallel to lead out to the pole lug III; when it is necessary to replenish active ions to the battery, the pole lug I is connected to the pole lug II / pole lug III through an external circuit to form a discharge circuit to achieve intermittent replenishment of active ions; or the pole lug I is connected in series with the pole lug II through a diode to achieve continuous replenishment of active ions.

Images