Pole piece, battery monomer and electric equipment

Abstract

The invention discloses a pole piece, a battery monomer and electric equipment, and the pole piece comprises a current collector substrate which comprises a supporting layer and a porous layer arranged on at least partial area of at least one side surface of the supporting layer; the conductive layer is at least arranged on the surface, away from the supporting layer, of the porous layer; and the active material layer is at least arranged on one side, far away from the porous layer, of the conductive layer. Therefore, the conductive layer can block substances with large molecular weight, such as active substances of the active substance layer, so as to maintain the pore form of the porous layer, so that an electrolyte with small molecular weight passes through the conductive layer and is stored in pores of the porous layer, and the effect that the current collector substrate absorbs and stores the electrolyte is realized; the infiltration effect of the electrolyte on the pole piece is effectively improved, the electrolyte can be supplemented in time in the charging and discharging process, and the problem of local liquid shortage of the pole piece is avoided.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and more specifically to a pole piece, a battery cell including the pole piece, and an electrical device including the battery cell. Background Art

[0002] As the demand for battery energy density increases, the energy density of batteries can be improved through design methods such as pole piece compaction. However, pole piece compaction will result in a denser surface of the current collector and less porosity, which will lead to insufficient electrolyte infiltration into the pole piece, thus affecting the battery's cycle performance. Summary of the invention

[0003] In view of this, the present application provides a pole piece, a battery cell including the pole piece, and an electrical device including the battery cell, which solves the problem of insufficient wetting of the pole piece by the electrolyte.

[0004] A pole piece, comprising:

[0005] A current collector matrix, comprising a support layer and a porous layer disposed on at least a portion of a surface of at least one side of the support layer;

[0006] A conductive layer, at least disposed on a surface of the porous layer away from the support layer;

[0007] The active material layer is provided at least on a side of the conductive layer away from the porous layer.

[0008] Optionally, in the above-mentioned pole piece, along the width direction of the pole piece, the support layer includes a middle area; and the porous layer is arranged in the middle area.

[0009] Optionally, in the above-mentioned pole piece,

[0010] The thickness of the current collector matrix is ​​12 μm-16 μm; and / or,

[0011] The thickness of the support layer is 10 μm-14 μm; and / or,

[0012] The thickness of the porous layer is 1 μm-3 μm; and / or,

[0013] The pore size of the porous layer is 1 μm-50 μm; and / or,

[0014] The porosity of the porous layer is 20%-60%.

[0015] Optionally, in the above-mentioned pole piece, along the thickness direction of the pole piece, the conductive layer includes a plurality of component layers; the component layers include at least one of a graphene layer, a silver layer, and a graphene silver-plated layer.

[0016] Optionally, in the above-mentioned pole piece,

[0017] The constituent layers include a granular layer; and / or,

[0018] Along the width and / or length direction of the pole piece, the component layer includes a plurality of sheet layers arranged at intervals; and along the thickness direction of the pole piece, adjacent sheet layers are staggered; and / or,

[0019] The number of the constituent layers is 2 to 10; and / or,

[0020] The thickness of the conductive layer is less than 1 μm; and / or,

[0021] The thickness of the constituent layer is 1 nm-10 nm.

[0022] Optionally, the electrode further comprises a lithium supplement layer, wherein the lithium supplement layer is at least arranged on a surface of the conductive layer away from the porous layer;

[0023] The active material layer is at least disposed on a surface of the lithium replenishing layer that is away from the conductive layer.

[0024] Optionally, in the above-mentioned electrode, the thickness of the lithium supplement layer is 5 μm-15 μm; and / or,

[0025] The lithium supplement layer includes a lithium supplement agent, and the lithium supplement agent includes at least one of lithium nickelate and lithium ferrite; and / or,

[0026] The lithium replenishing layer includes a conductive agent, and the conductive agent includes at least one of conductive carbon black, conductive graphite KS-6, conductive graphite SFG-6, Ketjen Black EC300J, Ketjen Black ECP, Ketjen Black ECP-600JD, carbon fiber, and carbon nanotubes; and / or,

[0027] The lithium replenishing layer includes a binder, and the binder includes at least one of polyvinyl pyrrolidone, polyvinylidene fluoride, polyethylene oxide, polytetrafluoroethylene, sodium carboxymethyl cellulose, and a copolymer of styrene and butadiene; and / or,

[0028] The lithium supplement layer includes a dispersant, and the dispersant includes at least one of polyoxyethylene dioleate and polyethylene glycol monostearate.

[0029] Optionally, in the above-mentioned electrode, the thickness of the active material layer is 50 μm-300 μm; and / or,

[0030] The active material layer includes at least one of a layered active material layer, a spinel type active material layer, and an olivine type active material layer.

[0031] A battery cell comprises the pole piece mentioned above.

[0032] An electrical device comprises the battery cell mentioned above.

[0033] In the pole piece, battery cell and electrical equipment provided by the present application, a porous layer is arranged on at least one side surface of the supporting layer of the current collector substrate of the pole piece, and a conductive layer is arranged on the surface of the porous layer; the conductive layer covers the surface of the porous layer, and can block substances with larger molecular weight, such as active substances in the active substance layer, so as to maintain the pore morphology of the porous layer, while allowing the electrolyte with smaller molecular weight to pass through the conductive layer and be stored in the pores of the porous layer; as above, the wetting effect of the electrolyte on the pole piece is effectively improved, and the electrolyte can be replenished in time during the charging and discharging process, avoiding the problem of local liquid shortage in the pole piece. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0035] Figure 1 A top view of the current collector of the present application;

[0036] Figure 2 for Figure 1 A top view after setting the conductive layer;

[0037] Figure 3 A cross-sectional view of a pole piece of the present application;

[0038] Figure 4 This is a schematic diagram of the structure of the current collector matrix of the present application;

[0039] Figure 5 This is a schematic diagram of the structure of the current collector of Example 1 of the present application;

[0040] Figure 6 is a schematic diagram of the structure of the conductive layer;

[0041] Figure 7 This is a schematic diagram of the structure of the current collector of Example 2 of the present application;

[0042] Figure 8 This is a schematic diagram of the structure of the pole piece of the present application.

[0043] Figure 1-Figure 8 middle:

[0044] 1. Current collector matrix; 2. Conductive layer; 3. Lithium replenishing layer; 4. Active material layer;

[0045] 11. Support layer; 12. Porous layer;

[0046] 21. Composition layer;

[0047] 211, lamella;

[0048] a, first edge; b, second edge; c, third edge; d, fourth edge. DETAILED DESCRIPTION

[0049] The present application provides a pole piece, and also provides a battery cell including the pole piece, and also provides an electrical device including the battery cell, wherein a porous layer is arranged on at least one side surface of a support layer of a current collector substrate, and a conductive layer is arranged on the surface of the porous layer; the conductive layer covers the surface of the porous layer, and can block substances with larger molecular weight, such as active substances in an active substance layer, so as to maintain the pore morphology of the porous layer, while allowing electrolyte with smaller molecular weight to pass through the conductive layer and be stored in the pores of the porous layer; as described above, the wetting effect of the electrolyte on the pole piece is effectively improved, and the electrolyte can be replenished in time during the charge and discharge process, thereby avoiding the problem of local liquid shortage of the pole piece.

[0050] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0051] like Figure 1-8 As shown, a pole piece includes a current collector matrix 1, a conductive layer 2, and an active material layer 4. The pole piece includes a current collector, and the current collector includes a current collector matrix 1 and a conductive layer 2. Please refer to the attached Figure 1 , 3 -4, the current collector substrate 1 comprises a support layer 11 and a porous layer 12; at least a portion of at least one side surface of the support layer 11 is provided with the porous layer 12. Figure 2 , 3 5. The conductive layer 2 is at least disposed on the surface of the porous layer 12 away from the support layer 11. Figure 3 , 8 , the active material layer 4 is at least arranged on the side of the conductive layer 2 away from the porous layer 12 .

[0052] It should be noted that the pole piece can be a positive pole piece or a negative pole piece. The current collector matrix 1 is a metal foil; when the pole piece is a positive pole piece, the current collector matrix 1 can be an aluminum foil. A dense foil layer can be obtained first, and then the surface of the foil layer is treated by chemical etching or laser etching, so that the surface layer of the foil layer forms a porous layer 12 with pores, and the structural layer of the foil layer that has not been treated by the above method forms a dense support layer 11, and finally the current collector matrix 1 is obtained. It is also possible to first obtain a dense support layer 11, and then set a porous layer 12 with pores on the surface of the support layer 11 to finally obtain the current collector matrix 1.

[0053] “A porous layer 12 is provided on at least a partial area of ​​at least one side surface of the support layer 11” includes the following types: ① A porous layer 12 is provided on one side surface of the support layer 11; ② A porous layer 12 is provided on both side surfaces of the support layer 11; ③ Based on ① or ②, a porous layer 12 is provided on the entire surface of the support layer 11; ④ Based on ① or ②, a porous layer 12 is provided on a local area of ​​the surface of the support layer 11.

[0054] "The conductive layer 2 is at least arranged on the surface of the porous layer 12 away from the supporting layer 11" includes the following types: ① The porous layer 12 is arranged on the entire surface of the supporting layer 11, and the conductive layer 2 covers the porous layer 12 (in this case, the conductive layer 2 covers the entire surface of the current collector matrix 1); ② The porous layer 12 is arranged on a part of the surface of the supporting layer 11, the conductive layer 2 covers the porous layer 12, and the conductive layer 2 also covers at least a part of the surface of the current collector matrix 1 except the porous layer 12; ③ The porous layer 12 is arranged on a part of the surface of the supporting layer 11, and the conductive layer 2 only covers the porous layer 12, but does not cover other areas of the surface of the current collector matrix 1 except the porous layer 12.

[0055] Furthermore, the current collector includes a current collector substrate 1 and a conductive layer 2. Regardless of the types of the porous layer 12 and the conductive layer 2, both sides of the current collector finally obtained are planes.

[0056] The conductive layer 2 is deposited on the surface of the current collector substrate 1 having the porous layer 12 , and the pore structure of the porous layer 12 can be retained after the coating of the active material layer 4 is completed. The conductive layer 2 can prevent substances other than the electrolyte from filling into the pores of the porous layer 12 .

[0057] The conductive layer 2 can block substances with larger molecular weight, such as the active substances in the active substance layer 4, so as to maintain the pore morphology of the porous layer 12, and allow the electrolyte with smaller molecular weight to pass through the conductive layer 2 and be stored in the pores of the porous layer 12; as above, the effect of the collector matrix 1 absorbing and storing the electrolyte is achieved, which effectively improves the wetting effect of the electrolyte on the electrode, and the electrolyte can be replenished in time during the charge and discharge process, avoiding the problem of local liquid shortage of the electrode.

[0058] Please refer to the attached Figure 1 , 3 In some embodiments of the present application, along the width direction of the pole piece, the support layer 11 includes a middle region; and the porous layer 12 is arranged in the middle region.

[0059] It should be noted that the width direction of the electrode sheet, that is, the width direction of the current collector, Figure 1 , 3 Direction indicated by the arrow.

[0060] In the manufactured battery cell, the problem of insufficient electrolyte infiltration in the middle area of ​​the pole piece is easy to occur. The porous layer 12 is only provided in the middle area of ​​the pole piece, and the processing time and processing cost of the porous layer 12 are maximized, so that the middle area of ​​the pole piece can absorb and store enough electrolyte, and then the middle area of ​​the pole piece can be well infiltrated by the electrolyte, and finally the overall infiltration effect of the entire area of ​​the pole piece is achieved; moreover, the middle area of ​​the pole piece can be replenished with electrolyte in time during the charging and discharging process, avoiding the problem of lack of electrolyte in the middle area of ​​the pole piece.

[0061] For further information, please see the attached Figure 3 , along the width direction of the pole piece, the support layer 11 includes a first edge a and a second edge b that are opposite to each other; along the width direction of the pole piece, the width of the support layer 11 is L, that is, the distance from the first edge a to the second edge b is L. Along the width direction of the pole piece, the middle area of ​​the support layer 11 includes a third edge c close to the first edge a and a fourth edge d close to the second edge b. Along the width direction of the pole piece, the distance from the third edge c to the first edge a is ≥L / 4, and the distance from the fourth edge d to the second edge b is ≥L / 4.

[0062] As described above, the position of the middle area of ​​the support layer 11 is limited, and then the position of setting the porous layer 12 is precisely controlled. Under the premise that the middle area of ​​the electrode absorbs and stores sufficient electrolyte, the disadvantage of excessive loss of supporting strength of the support layer 11 caused by the porous layer 12 being set too large is avoided.

[0063] Please refer to the attached Figure 4In some embodiments of the present application, the thickness of the current collector matrix 1 is 12μm-16μm; for example, the thickness of the current collector matrix 1 can be any one of 12μm, 12.5μm, 13μm, 13.5μm, 14μm, 14.5μm, 15.5μm, and 16μm.

[0064] Furthermore, the thickness of the support layer 11 is 10 μm-14 μm; for example, the thickness of the support layer 11 may be any one of 10 μm, 10.5 μm, 11 μm, 11.5 μm, 12 μm, 12.5 μm, 13 μm, 13.5 μm, and 14 μm.

[0065] Furthermore, the thickness of the porous layer 12 is 1 μm-3 μm; for example, the thickness of the porous layer 12 can be any one of 1 μm, 1.5 μm, 2 μm, 2.5 μm, and 3 μm.

[0066] The thickness of the support layer 11, the porous layer 12 and the current collector matrix 1 is limited within the above range, which can ensure that the volume energy density of the battery cell monomer is ensured while ensuring that the current collector matrix 1 has sufficient processing strength and support strength, as well as sufficient space for storing electrolyte to ensure the overall wetting effect of the electrode.

[0067] In some embodiments of the present application, the pore size of the porous layer 12 is 1 μm-50 μm; for example, the pore size of the porous layer 12 can be any one of 1 μm, 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, and 50 μm.

[0068] As described above, the pore size of the porous layer 12 can be within a reasonable range, so that the porous layer 12 has a certain support strength, is conducive to the rapid diffusion of the electrolyte, and increases the transmission rate of lithium ions.

[0069] Furthermore, the porosity of the porous layer 12 is 20%-60%; for example, the porosity of the porous layer 12 may be any one of 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, and 60%.

[0070] As described above, the porosity of the porous layer 12 can be within a reasonable range, further ensuring the support strength of the porous layer 12, and being able to store a sufficient amount of electrolyte to ensure the overall wetting effect of the electrode.

[0071] Please see attached Figure 5-6 In some embodiments of the present application, along the thickness direction of the current collector, the conductive layer 2 includes a plurality of component layers 21. The component layer 21 includes at least one of a graphene layer, a silver layer, and a graphene silver-plated layer.

[0072] The conductive layer 2 is a structure in which several component layers 21 are stacked layer by layer, which not only helps to enhance the bonding force between the component layers 21 and the current collector substrate 1, as well as the bonding force between the component layers 21, but also enhances the bonding strength of the conductive layer 2 itself, thereby avoiding peeling or breakage during the manufacture or use of the battery cell; moreover, compared with a one-time thick layer deposition, multiple thin layer depositions of the component layers 21 make it easier to obtain a uniform conductive layer 2, which helps to improve the structural stability and consistency of the conductive layer 2.

[0073] The graphene layer, silver layer, and graphene silver-plated layer all have extremely high electron mobility and conductivity. Covering them on the surface of the porous layer 12 of the current collector matrix 1 can improve the conductivity and stability of the electrode while ensuring that the electrolyte can pass through and enter the pores of the porous layer 12.

[0074] In some embodiments of the present application, the component layer 21 includes a particle layer. There are gaps between particles in the particle layer, so that the electrolyte passes through the gaps and enters the pores of the porous layer 12.

[0075] Please see attached Figure 6 In some embodiments, along the width and / or length direction of the electrode sheet, the component layer 21 includes a plurality of sheet layers 211 arranged at intervals. There are gaps between the sheet layers 211, so that the electrolyte passes through the gaps and enters the pores of the porous layer 12.

[0076] Furthermore, along the thickness direction of the pole piece, adjacent sheet layers 211 are staggered.

[0077] It should be noted that, “along the thickness direction of the pole piece, adjacent sheet layers 211 are staggered” means that Figure 6 : In two adjacent component layers 21 along the thickness direction of the pole piece, there is a first gap between adjacent sheets 211 in the upper component layer 21, and there is a second gap between adjacent sheets 211 in the lower component layer 21. The first gap and the second gap are not aligned along the thickness direction of the pole piece, and the two form a misaligned gap. As above, it can be ensured that in the cross section perpendicular to the thickness direction of the pole piece, the projection of the conductive layer 2 completely covers the projection of the porous layer 12, avoiding the drawback that the projection of the conductive layer 2 has a blank area due to the "alignment of the first gap and the second gap", thereby preventing the porous layer 12 from being completely covered.

[0078] In certain embodiments of the present application, the number of layers of the component layer 21 is 2-10 layers, for example, it can be 2 layers, 3 layers, 4 layers, 5 layers, 6 layers, 7 layers, 8 layers, 9 layers, or 10 layers.

[0079] As described above, the disadvantages of complicated and time-consuming process caused by too many layers of the component layers 21 are avoided, and the bonding strength between the layers of the component layers 21 and the stability and consistency of the conductive layer 2 obtained can be ensured.

[0080] In some embodiments, the thickness of the conductive layer 2 is less than 1 μm. Further, the thickness of the component layer 21 is 1 nm-10 nm; for example, the thickness of the component layer 21 can be any one of 1 nm, 2 nm, 3 nm, 4 nm, 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, and 10 nm.

[0081] As described above, under the premise of ensuring the volume energy density of the manufactured battery cell, the thin layer deposition thickness of the single-layer component layer 21 is guaranteed, so that there is sufficient bonding force between the layers of each component layer 21, and the manufactured conductive layer 2 has sufficient stability and consistency.

[0082] In some preferred embodiments, the conductive layer 2 has two component layers 21, and both component layers 21 are graphene layers. In some more preferred embodiments, the conductive layer 2 has 3-10 component layers 21, and all component layers 21 are graphene layers. As above, after the graphene layers are stacked, the active material of the active material layer 4 can be blocked from entering the pores of the porous layer 12, thereby preventing the pores of the porous layer 12 from being filled, and after the graphene layers are stacked, dislocation gaps will be formed between each other, and these dislocation gaps can allow the electrolyte to pass through, so that the electrolyte is stored in the pores of the porous layer 12. At the same time, the graphene layer is light in weight and highly conductive, ensuring the energy density and electrochemical performance of the battery cell.

[0083] Please refer to the attached Figure 7 In some embodiments of the present application, the electrode further includes a lithium replenishing layer 3, which is at least arranged on the surface of the conductive layer 2 away from the porous layer 12; the active material layer 4 is at least arranged on the surface of the lithium replenishing layer 3 away from the conductive layer 2.

[0084] It should be noted that "the lithium-replenishing layer 3 is at least arranged on the surface of the conductive layer 2 away from the porous layer 12", which includes the following types: ① The conductive layer 2 covers the entire area of ​​the surface of the current collector matrix 1, and the lithium-replenishing layer 3 covers the conductive layer 2 (at this time, the lithium-replenishing layer 3 covers the entire area of ​​the surface of the current collector matrix 1); ② The conductive layer 2 covers a partial area of ​​the surface of the current collector matrix 1, the lithium-replenishing layer 3 covers the conductive layer 2, and the lithium-replenishing layer 3 covers at least a partial area of ​​the surface of the current collector matrix 1 except the conductive layer 2; ③ The conductive layer 2 covers a partial area of ​​the surface of the current collector matrix 1, and the lithium-replenishing layer 3 only covers the conductive layer 2, and does not cover other areas of the surface of the current collector matrix 1 except the conductive layer 2.

[0085] Furthermore, the current collector includes a current collector substrate 1, a conductive layer 2 and a lithium replenishing layer 3. Regardless of the types of the porous layer 12, the conductive layer 2 and the lithium replenishing layer 3, both sides of the final current collector have flat surfaces.

[0086] It should be further explained that the conductive layer 2 can block the lithium supplement agent of the lithium supplement layer 3 with a relatively large molecular weight, so as to maintain the pore morphology of the porous layer 12 .

[0087] By providing the lithium replenishing layer 3, the lithium ions in the electrolyte inside the lithium battery monomer can be fully replenished, so that the lithium battery monomer has good cycle stability and service life. Furthermore, due to the presence of the conductive layer 2, the conductivity of the lithium replenishing layer 3 can be enhanced, avoiding the lithium replenishing layer 3 from having a large polarization effect during the lithium replenishing process, and being able to fully decompose and release lithium ions in a large charging current and a short charging time, thereby ensuring the lithium replenishing efficiency.

[0088] In some embodiments of the present application, the thickness of the lithium replenishing layer 3 is 5μm-15μm; for example, the thickness of the lithium replenishing layer 3 can be any one of 5μm, 6μm, 7μm, 8μm, 9μm, 10μm, 11μm, 12μm, 13μm, 14μm, and 15μm.

[0089] As described above, the lithium replenishing layer 3 and the conductive layer 2 work together to ensure the total amount of lithium in the lithium replenishing layer 3 and the lithium replenishing effect under the premise of ensuring the volume energy density of the manufactured battery cell.

[0090] In some embodiments of the present application, the lithium replenishing layer 3 includes a lithium replenishing agent, a conductive agent, a binder, and a dispersant.

[0091] The lithium replenisher, conductive agent, binder and dispersant in the lithium replenisher layer 3 complement each other. The lithium replenisher ensures the total amount of lithium, the conductive agent and binder optimize the electron and ion transmission of the electrode, and the dispersant ensures that the lithium replenisher layer 3 has good uniformity and stability.

[0092] In some embodiments, the lithium supplement includes at least one of lithium nickelate and lithium ferrite. Preferably, the lithium supplement is lithium ferrite.

[0093] Furthermore, the conductive agent includes at least one of conductive carbon black, conductive graphite KS-6, conductive graphite SFG-6, Ketjen black EC300J, Ketjen black ECP, Ketjen black ECP-600JD, carbon fiber, and carbon nanotubes.

[0094] Furthermore, the binder includes at least one of polyvinyl pyrrolidone, polyvinylidene fluoride, polyethylene oxide, polytetrafluoroethylene, sodium carboxymethyl cellulose, and a copolymer of styrene and butadiene.

[0095] Furthermore, the dispersant includes at least one of polyoxyethylene dioleate and polyethylene glycol monostearate.

[0096] As mentioned above, by precisely controlling the types of lithium replenisher, conductive agent, binder and dispersant, the complementary nature of the two can make the prepared lithium replenisher layer 3 have better lithium replenishment efficiency and better conductivity; the lithium replenisher layer 3 can quickly compensate for the loss of lithium, reduce the battery capacity attenuation caused by the reduction of lithium inventory, and thus extend the cycle life of the battery cell.

[0097] In some embodiments of the present application, the thickness of the active material layer 4 is 50 μm-300 μm; for example, the thickness of the active material layer 4 is any one of 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 150 μm, 200 μm, 250 μm, and 300 μm.

[0098] As described above, under the premise of ensuring the volume energy density of the manufactured battery cell, the active material layer 4 contains sufficient materials capable of inserting and extracting lithium ions to ensure the volume energy density and battery capacity of the battery.

[0099] In some embodiments, the active material layer 4 includes at least one of a layered active material layer, a spinel type active material layer, and an olivine type active material layer.

[0100] The layered active material layer has the advantages of high energy density, good electrochemical performance, faster lithium ion diffusion, and better structural stability; the spinel active material layer has the advantages of low cost, high safety, long cycle life, and good thermal stability; the olivine active material layer has the advantages of extremely high safety, low cost, long cycle life, and a wide temperature operating range; the appropriate type of active material layer 4 can be selected according to actual needs, and it is flexible and highly applicable.

[0101] Example 1 (positive electrode sheet does not include lithium replenishment layer)

[0102] Please see attached Figure 3 , the electrode is a positive electrode, and the processing process of the positive electrode is as follows:

[0103] (1) Please refer to the attached Figure 1 An aluminum foil layer is selected, and the two sides of the aluminum foil layer have a first middle region and a second middle region respectively; the first middle region and the second middle region are processed by chemical etching to obtain two porous layers 12 respectively; the area of ​​the aluminum foil layer that has not been chemically etched is a dense support layer 11;

[0104] (2) Please refer to the attached Figure 2, depositing conductive layers 2 on the surfaces of the two porous layers 12 respectively (specifically, the conductive layer 2 includes two component layers 21, each of which is a graphene layer), the conductive layer 2 covers the porous layer 12, and the conductive layer 2 does not protrude from the surface of the current collector substrate 1;

[0105] (3) Please refer to the attached Figure 3 , an active material layer 4 is coated on the conductive layer 2 , and the active material layer 4 covers the conductive layer 2 and the entire surface area of ​​the current collector substrate 1 .

[0106] Embodiment 2 (positive electrode sheet including lithium supplement layer)

[0107] Please see attached Figure 8 , the electrode is a positive electrode, and the processing process of the positive electrode is as follows:

[0108] (1) Please refer to the attached Figure 4 , an aluminum foil layer is selected, and the entire area of ​​the two sides of the aluminum foil layer is processed by chemical etching to obtain two porous layers 12; the area between the two porous layers 12 is a dense support layer 11;

[0109] (2) Please refer to the attached Figure 5-6 , depositing conductive layers 2 on the surfaces of the two porous layers 12 respectively (specifically, the conductive layer 2 includes 6 component layers 21 , and each component layer 21 is a graphene layer);

[0110] (3) Please refer to the attached Figure 7 , coating a lithium replenishing layer 3 on the conductive layer 2;

[0111] (4) Please refer to the attached Figure 8 , an active material layer 4 is coated on the lithium replenishing layer 3 .

[0112] Based on the above-mentioned pole piece, the embodiment of the present application further provides a battery cell, which includes a pole piece, and the pole piece is the pole piece described above. The battery cell includes a positive pole piece and a negative pole piece; the positive pole piece and / or the negative pole piece is the pole piece described above. Preferably, the positive pole piece is the pole piece described above.

[0113] The battery cell may be a secondary battery cell, which refers to a battery cell that can be used continuously by activating the active material by charging after the battery is discharged. The battery cell may be a lithium-ion battery cell, a sodium-ion battery cell, a sodium-lithium-ion battery cell, a lithium metal battery cell, a sodium metal battery cell, a lithium-sulfur battery cell, a magnesium-ion battery cell, a nickel-hydrogen battery cell, a nickel-cadmium battery cell, a lead-acid battery cell, etc., and the embodiments of the present application do not limit this. As an example, the battery cell may be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell, or a battery cell of other shapes. The prismatic battery cell includes a square shell battery cell, a blade-shaped battery cell, and a multi-prismatic battery cell. The multi-prismatic battery cell is, for example, a hexagonal battery cell, etc., and the present application has no special restrictions. Preferably, the battery cell is a lithium-ion battery cell, and the battery cell is a blade-shaped battery cell.

[0114] Since the battery cell includes the pole piece mentioned above, the beneficial effects of the battery cell brought by the pole piece can be found above and will not be described in detail here.

[0115] Based on the above-mentioned battery cells, an embodiment of the present application further provides an electrical device, which includes a battery cell, and the battery cell is the battery cell described above.

[0116] In some embodiments, a battery refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity.

[0117] In some embodiments, when there are multiple batteries, the multiple batteries are arranged and fixed to form a battery module.

[0118] In some embodiments, a battery pack includes a case, and batteries or battery modules accommodated in the case.

[0119] Battery cells or batteries or battery packs provide power for electrical equipment. Electrical equipment can be in various forms, for example, cars, mobile phones, portable devices, laptops, ships, spacecraft, electric toys and electric tools, etc. Cars can be fuel cars, gas cars or new energy cars, and new energy cars can be pure electric cars, hybrid cars or extended-range cars, etc.; spacecraft include airplanes, rockets, space shuttles and spacecraft, etc.; electric toys include fixed or mobile electric toys, for example, game consoles, electric car toys, electric ship toys and electric airplane toys, etc.; electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools and railway electric tools, for example, electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators and electric planers, etc. This article does not impose any special restrictions on the above-mentioned electrical devices.

[0120] Since the electrical device includes the battery cells mentioned above, the beneficial effects of the battery cells on the electrical device can be found above and will not be described in detail here.

[0121] The components and devices involved in this application are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the drawings. As will be appreciated by those skilled in the art, these components and devices can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, meaning "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The word "such as" used here refers to the phrase "such as but not limited to", and can be used interchangeably with it.

[0122] It should also be noted that in the device of the present application, each component can be decomposed and / or reassembled, and these decompositions and / or reassemblies should be regarded as equivalent solutions of the present application.

[0123] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present application. Therefore, the present application is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0124] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

[0125] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A pole piece, characterized in that: include: A current collector matrix (1) comprising a support layer (11) and a porous layer (12) disposed on at least a portion of a surface of at least one side of the support layer (11); A conductive layer (2) is at least arranged on a surface of the porous layer (12) away from the support layer (11); The active material layer (4) is at least arranged on a side of the conductive layer (2) away from the porous layer (12).

2. The pole piece according to claim 1, characterized in that: Along the width direction of the pole piece, the support layer (11) includes a middle region; and the porous layer (12) is arranged in the middle region.

3. The pole piece according to claim 1, characterized in that: The thickness of the current collector matrix (1) is 12 μm-16 μm; and / or, The thickness of the support layer (11) is 10 μm-14 μm; and / or, The thickness of the porous layer (12) is 1 μm-3 μm; and / or, The pore size of the porous layer (12) is 1 μm-50 μm; and / or, The porosity of the porous layer (12) is 20%-60%.

4. The pole piece according to claim 1, characterized in that: Along the thickness direction of the pole piece, the conductive layer (2) comprises a plurality of component layers (21); the component layers (21) comprise at least one of a graphene layer, a silver layer, and a graphene silver-plated layer.

5. The pole piece according to claim 4, characterized in that: The component layer (21) includes a particle layer; and / or, Along the width and / or length direction of the pole piece, the component layer (21) includes a plurality of sheet layers (211) arranged at intervals; and along the thickness direction of the pole piece, adjacent sheet layers (211) are staggered; and / or, The number of the component layers (21) is 2 to 10; and / or, The thickness of the conductive layer (2) is less than 1 μm; and / or, The thickness of the component layer (21) is 1 nm-10 nm.

6. The pole piece according to any one of claims 1 to 5, characterized in that: It also comprises a lithium replenishing layer (3), wherein the lithium replenishing layer (3) is at least arranged on a surface of the conductive layer (2) away from the porous layer (12); The active material layer (4) is at least arranged on a surface of the lithium replenishing layer (3) away from the conductive layer (2).

7. The pole piece according to claim 6, characterized in that: The thickness of the lithium replenishing layer (3) is 5 μm-15 μm; and / or, The lithium replenishing layer (3) comprises a lithium replenishing agent, wherein the lithium replenishing agent comprises at least one of lithium nickelate and lithium ferrite; and / or, The lithium replenishing layer (3) comprises a conductive agent, wherein the conductive agent comprises at least one of conductive carbon black, conductive graphite KS-6, conductive graphite SFG-6, Ketjen Black EC300J, Ketjen Black ECP, Ketjen Black ECP-600JD, carbon fiber, and carbon nanotubes; and / or, The lithium replenishing layer (3) comprises a binder, wherein the binder comprises at least one of polyvinyl pyrrolidone, polyvinylidene fluoride, polyethylene oxide, polytetrafluoroethylene, sodium carboxymethyl cellulose, and a copolymer of styrene and butadiene; and / or, The lithium supplement layer (3) comprises a dispersant, and the dispersant comprises at least one of polyoxyethylene dioleate and polyethylene glycol monostearate.

8. The pole piece according to claim 1, characterized in that: The thickness of the active material layer (4) is 50 μm-300 μm; and / or, The active material layer (4) includes at least one of a layered active material layer, a spinel type active material layer, and an olivine type active material layer.

9. A battery cell, characterized in that: Comprising a pole piece as claimed in any one of claims 1 to 8.

10. An electrical device, characterized in that: Comprising the battery cell as claimed in claim 9.

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