CN220692277U

CN220692277U - Current collector, pole piece, battery monomer, battery and power utilization device

Info

Publication number: CN220692277U
Application number: CN202420064578.2U
Authority: CN
Inventors: 王细辉; 许文竹
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2024-01-11
Filing date: 2024-01-11
Publication date: 2024-03-29
Anticipated expiration: 2034-01-11

Abstract

The application discloses a current collector, a pole piece, a battery monomer, a battery and an electricity utilization device. The current collector comprises an insulating part, a positive electrode conductive substrate and a negative electrode conductive substrate, wherein the insulating part comprises a first surface and a second surface which are oppositely arranged along a first direction, and the insulating part is provided with a through hole penetrating through the first surface and the second surface; wherein the first direction is the thickness direction of the insulating part; the positive electrode conductive substrate is arranged on the first surface of the insulation part; the negative electrode conductive base material is arranged on the second surface of the insulating part, part of the positive electrode conductive base material and/or part of the negative electrode conductive base material is filled in the through hole, and the positive electrode conductive base material and the negative electrode conductive base material are conducted through the through hole. The application reduces additional electrical connections and can improve the energy density of the battery cell.

Description

Current collector, pole piece, battery monomer, battery and power utilization device

Technical Field

The application relates to the technical field of batteries, in particular to a current collector, a pole piece, a battery cell, a battery and an electric device.

Background

Battery cells are widely used in electronic devices such as cellular phones, notebook computers, battery cars, electric vehicles, electric airplanes, electric ships, electric toy vehicles, electric toy ships, electric toy airplanes, electric tools, and the like. The battery cells may include cadmium-nickel battery cells, hydrogen-nickel battery cells, lithium ion battery cells, secondary alkaline zinc-manganese battery cells, and the like.

In the development of battery technology, how to increase the energy density of a battery cell is one research direction in battery technology.

Disclosure of Invention

The embodiment of the application provides a current collector, a pole piece, a battery monomer, a battery and an electricity utilization device, which can improve the reliability of the battery.

In a first aspect, embodiments of the present application provide a current collector, including an insulating portion, a positive electrode conductive substrate, and a negative electrode conductive substrate, where the insulating portion includes a first surface and a second surface that are disposed opposite to each other along a first direction, and the insulating portion is provided with a through hole penetrating the first surface and the second surface; wherein the first direction is the thickness direction of the insulating part; the positive electrode conductive substrate is arranged on the first surface of the insulation part; the negative electrode conductive base material is arranged on the second surface of the insulating part, part of the positive electrode conductive base material and/or part of the negative electrode conductive base material is filled in the through hole, and the positive electrode conductive base material and the negative electrode conductive base material are conducted through the through hole.

In the above scheme, the positive electrode conductive base material and the negative electrode conductive base material are respectively arranged on the first surface and the second surface of the insulating part, so that the conduction of the front surface and the back surface of the current collector can be realized. Through the through-hole that runs through first surface and second surface is followed to its thickness direction setting at the insulating part, the material of the anodal conductive substrate and/or the electrically conductive substrate of negative pole is filled in the through-hole for anodal conductive substrate and electrically conductive substrate of negative pole are switched on through the through-hole, need not to carry out conductive connection through the utmost point ear, have reduced extra electrical connection, can improve the energy density of battery monomer.

In some embodiments, the insulating portion includes a current collecting region and a sealing region circumferentially disposed around the current collecting region, and the positive conductive substrate and the negative conductive substrate respectively cover the current collecting region of the insulating portion.

In the scheme, the edge sealing areas among the current collectors can be mutually attached and connected, electrolyte can be sealed, and the leakage risk is reduced.

In some embodiments, the width of the edge seal is L1, L1 satisfying the following conditions: l1 is less than or equal to 1mm and less than or equal to 150mm, so that the sealing performance of the electrolyte can be ensured to a certain extent, the leakage risk is reduced, and the battery monomer can be ensured to have higher energy density to a certain extent.

In some embodiments, L1 satisfies the following condition: l1 is more than or equal to 1mm and less than or equal to 15mm, so that the leakage risk is further reduced, and the battery monomer is ensured to have higher energy density to a certain extent.

In some embodiments, the orthographic projection of the positive conductive substrate on the insulating portion is within the orthographic projection of the negative conductive substrate on the insulating portion.

In the above scheme, the area of the negative electrode conductive base material is set larger, so that the negative electrode conductive base material can be wrapped, and the lithium precipitation phenomenon is reduced.

In some embodiments, the positive projection of the negative conductive substrate at the insulating portion exceeds the positive projection of the positive conductive substrate at the insulating portion by a width L2, L2 satisfying the following condition: l2 is more than or equal to 0mm and less than or equal to 20mm, which not only can reduce the phenomenon of lithium precipitation, but also can ensure that the battery monomer has higher energy density to a certain extent.

In some embodiments, L2 satisfies the following condition: l2 is more than or equal to 1mm and less than or equal to 10mm, thereby further reducing the phenomenon of lithium precipitation and improving the energy density of the battery monomer.

In some embodiments, the thickness of the portion of the positive electrode conductive substrate or the negative electrode conductive substrate filled in the through hole is L3, and L3 satisfies the following condition: l3 is more than or equal to 0 mu m and less than or equal to 20 mu m, so that the overcurrent capacity can be ensured to a certain extent, and the energy density of the battery monomer can be improved.

In some embodiments, L3 satisfies the following condition: l3 is more than or equal to 0.5 mu m and less than or equal to 10 mu m, so that the overcurrent capacity is further ensured to a certain extent, and the energy density of the battery monomer can be improved.

To a certain extent, the material of the positive electrode conductive substrate includes aluminum, the material of the negative electrode conductive substrate includes copper, and the thickness of the portion of the positive electrode conductive substrate filled in the through hole is greater than the thickness of the portion of the negative electrode conductive substrate filled in the through hole.

In the scheme, the through holes are filled with more materials of the positive electrode conductive base material with relatively cheap raw materials, so that the production cost of the battery cell can be reduced.

In some embodiments, the thickness of the positive conductive substrate on the first surface or the negative conductive substrate on the second surface is L4, L4 satisfying the following condition: l4 is more than or equal to 0.5 mu m and less than or equal to 100 mu m, so that the overcurrent capacity can be ensured to a certain extent, and the energy density of the battery monomer can be improved.

In some embodiments, L4 satisfies the following condition: l4 is more than or equal to 0.5 mu m and less than or equal to 10 mu m, so that the overcurrent capacity is further ensured to a certain extent, and the energy density of the battery monomer can be improved.

In a second aspect, an embodiment of the present application provides a pole piece, including an anode active layer, a cathode active layer, and a current collector of any one of the foregoing embodiments, where the anode active layer is disposed on a side of an anode conductive substrate facing away from an insulating portion; the negative electrode active layer is arranged on one side of the negative electrode conductive base material, which is away from the insulation part.

In a third aspect, embodiments of the present application provide a battery cell including a housing and an electrode assembly, the housing having an electrolyte disposed therein; the electrode assembly is accommodated in the shell and comprises a plurality of isolating films and a plurality of pole pieces in any one of the embodiments, and the isolating films are arranged between the adjacent pole pieces.

In some embodiments, the insulating portion includes a current collecting region and a sealing region circumferentially surrounding the current collecting region, and the positive electrode conductive substrate and the negative electrode conductive substrate respectively cover the current collecting region of the insulating portion; the edge sealing areas of the pole pieces are mutually connected, and electrolyte is sealed between the pole pieces, so that the risk of liquid leakage is reduced.

In some embodiments, the case includes first and second sub-cases disposed at opposite sides of the electrode assembly in the first direction, respectively; the first sub-shell comprises a first conductive part and first sealing parts arranged at two ends of the first conductive part along the second direction; the second sub-case includes a second conductive part and second sealing parts disposed at both ends of the second conductive part in a second direction; the first conductive part and the second conductive part are respectively and electrically connected with the electrode assembly, and the first sealing part and the second sealing part are in one-to-one corresponding sealing connection; wherein the second direction is disposed to intersect the first direction.

In the scheme, the electric energy of the battery cell is output or input through the first conductive part and the second conductive part. The first sealing part of the first sub-shell and the second sealing part of the second sub-shell which are oppositely arranged are in sealing connection, so that the sealing of the battery cell can be realized, the space can be saved, and the energy density of the battery can be improved.

In some embodiments, one end of the first conductive part along the second direction is provided with a first groove, and the other end is provided with a first convex part matched with the first groove; and/or one end of the second conductive part along the second direction is provided with a second groove, and the other end of the second conductive part is provided with a second part matched with the second groove.

The parallel connection between the battery cells may be achieved by inserting a first protrusion of a battery cell into a first recess of an adjacent battery cell and/or inserting a second protrusion of a battery cell into a second recess of an adjacent battery cell.

In some embodiments, a side of the first conductive portion facing away from the electrode assembly is concavely disposed with respect to the first sealing portion to form a recess; the side of the second conductive part, which is away from the electrode assembly, is convexly arranged relative to the second sealing part to form a bulge matched with the concave part.

In the above-described aspect, the series connection between the battery cells can be achieved by inserting the raised portions of the battery cells into the recessed portions of the adjacent battery cells.

In a fourth aspect, embodiments of the present application provide a battery comprising a battery cell according to any of the above embodiments.

In a fifth aspect, an embodiment of the present application provides an electrical device, including a battery cell or a battery of any one of the foregoing embodiments, where the battery cell or the battery is used to provide electrical energy.

The foregoing description is merely an overview of the technical solutions of the present application, and may be implemented according to the content of the specification in order to make the technical means of the present application more clearly understood, and in order to make the features and advantages of the present application more comprehensible, the following detailed description of the present application is given.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic illustration of a vehicle according to some embodiments of the present application;

fig. 2 is a schematic structural view of a battery according to some embodiments of the present application;

Fig. 3 is a schematic view of the structure of the battery module shown in fig. 2;

FIG. 4 is a schematic structural view of an insulating portion according to some embodiments of the present application;

FIG. 5 is a schematic cross-sectional view of a current collector according to some embodiments of the present application;

FIG. 6 is a top view of a current collector according to some embodiments of the present application;

FIG. 7 is a schematic cross-sectional view of a current collector according to further embodiments of the present application;

FIG. 8 is a schematic cross-sectional view of a pole piece according to some embodiments of the present application;

FIG. 9 is an exploded schematic view of a battery cell according to some embodiments of the present application;

fig. 10 is a schematic structural view of a battery cell according to some embodiments of the present application.

Reference numerals illustrate:

1000. a vehicle; 100. a battery; 200. a controller; 300. a motor; 10. an upper cover; 20. a battery cell; 30. a case; 22. a housing; 23. an electrode assembly; 24. a separation film; 25. a first sub-shell; 251. a first conductive portion; 252. a first sealing part; 26. a second sub-shell; 261. a second conductive portion; 262. a second sealing part; 271. a first groove; 272. a first convex portion; 281. a second groove; 282. a second convex portion; 291. a concave portion; 292. a bulge; 400. a current collector; 40. an insulating part; 41. a first surface; 42. a second surface; 43. a through hole; 44. a current collecting region; 45. edge sealing areas; 51. a positive electrode conductive substrate; 52. a negative electrode conductive substrate; 500. a pole piece; 61. a positive electrode active layer; 62. a negative electrode active layer; x, a first direction; y, second direction.

Detailed Description

Embodiments of the present application are described in further detail below with reference to the accompanying drawings and examples. The following detailed description of the embodiments and the accompanying drawings are provided to illustrate the principles of the present application and are not intended to limit the scope of the application, i.e., the application is not limited to the embodiments described.

In the description of the present application, it is to be noted that, unless otherwise indicated, the meaning of "plurality" is two or more; the terms "upper," "lower," "left," "right," "inner," "outer," and the like indicate an orientation or positional relationship merely for convenience of description and to simplify the description, and do not indicate or imply that the devices or elements being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus are not to be construed as limiting the present application. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. The "vertical" is not strictly vertical but is within the allowable error range. "parallel" is not strictly parallel but is within the tolerance of the error.

Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly understand that the embodiments described herein may be combined with other embodiments.

The directional terms appearing in the following description are all directions shown in the drawings and do not limit the specific structure of the present application. In the description of the present application, it should also be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the terms in the present application can be understood as appropriate by one of ordinary skill in the art.

In the present application, the battery cell may include a lithium ion secondary battery, a lithium ion primary battery, a lithium sulfur battery, a sodium lithium ion battery, a sodium ion battery, a magnesium ion battery, or the like, which is not limited by the embodiment of the present application. The battery cells may be cylindrical, flat, rectangular, or otherwise shaped, as well as the embodiments herein are not limited in this regard. The battery cells are generally classified into three types according to the packaging method: the cylindrical battery cell, the square battery cell and the soft package battery cell are not limited thereto.

Reference to a battery in embodiments of the present application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in the present application may include a battery module or a battery pack, or the like. The battery generally includes a case for enclosing one or more battery cells. The case body can prevent liquid or other foreign matters from affecting the charge or discharge of the battery cells.

The battery cell includes an electrode assembly and an electrolyte, and at present, the electrode assembly is generally composed of a positive electrode sheet, a negative electrode sheet and a separator. The battery cell mainly relies on metal ions to move between the positive and negative electrode plates to operate. The positive plate comprises a positive electrode current collector and a positive electrode active material layer, wherein the positive electrode active material layer is coated on the surface of the positive electrode current collector, the current collector without the positive electrode active material layer protrudes out of the current collector coated with the positive electrode active material layer, and the current collector without the positive electrode active material layer is laminated to serve as a positive electrode lug. In the charge and discharge process of the battery, the positive electrode active material and the negative electrode active material react with the electrolyte, and the positive electrode tab and the negative electrode tab are connected with the electrode terminal to form a current loop. The arrangement of the positive electrode tab and the negative electrode tab increases the structural occupation space of the electrode assembly and reduces the energy density of the battery cell.

In view of this, the present application provides a technical solution in which the front and back sides of the current collector can be electrically conductive by disposing the positive electrode conductive substrate and the negative electrode conductive substrate on the first surface and the second surface of the insulating portion, respectively. Through the through-hole that runs through first surface and second surface is followed to its thickness direction setting at the insulating part, the material of the anodal conductive substrate and/or the electrically conductive substrate of negative pole is filled in the through-hole for anodal conductive substrate and electrically conductive substrate of negative pole are switched on through the through-hole, need not to carry out conductive connection through the utmost point ear, have reduced extra electrical connection, can improve the energy density of battery monomer.

The battery cell disclosed by the embodiment of the application can be used in electric devices such as vehicles, ships or aircrafts, but is not limited to the electric devices. The power supply system with the battery cells, batteries and the like disclosed by the application can be used for forming the power utilization device, so that the stability of the battery performance and the service life of the battery are improved.

The embodiment of the application provides an electricity utilization device using a battery as a power supply, wherein the electricity utilization device can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft and the like. The electric toy may include fixed or mobile electric toys, such as game machines, electric car toys, electric ship toys, and electric plane toys, and the like, and the spacecraft may include planes, rockets, space planes, and spacecraft, and the like.

For convenience of description, the following embodiment will take an electric device according to an embodiment of the present application as an example of the vehicle 1000.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1000 according to some embodiments of the present application. The vehicle 1000 may be a fuel oil vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or a range-extended vehicle. The battery 100 is provided in the interior of the vehicle 1000, and the battery 100 may be provided at the bottom or the head or the tail of the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, for example, the battery 100 may be used as an operating power source of the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to power the motor 300, for example, for operating power requirements during start-up, navigation, and travel of the vehicle 1000.

In some embodiments of the present application, battery 100 may not only serve as an operating power source for vehicle 1000, but may also serve as a driving power source for vehicle 1000, instead of or in part instead of fuel oil or natural gas, to provide driving power for vehicle 1000.

Referring to fig. 2, fig. 2 is an exploded view of a battery 100 according to some embodiments of the present application. The battery 100 includes a case and a battery cell 20. In some embodiments, the case may include an upper cover 10 and a case 30, the upper cover 10 and the case 30 being covered with each other, the upper cover 10 and the case 30 together defining a receiving space for receiving the battery cell 20. The case 30 may have a hollow structure with one end opened, and the upper cover 10 may have a plate-shaped structure, and the upper cover 10 covers the opening side of the case 30, so that the upper cover 10 and the case 30 together define an accommodating space; the upper cover 10 and the case 30 may be hollow structures with one side open, and the open side of the upper cover 10 may be closed to the open side of the case 30. Of course, the case formed by the upper cover 10 and the case 30 may be of various shapes, such as a cylinder, a rectangular parallelepiped, etc.

Fig. 3 is a schematic structural view of a battery module. In the battery 100, the plurality of battery cells 20 may be connected in series, parallel or a series-parallel connection, wherein the series-parallel connection refers to that the plurality of battery cells 20 are connected in series or parallel. The plurality of battery cells 20 can be directly connected in series or in parallel or in series-parallel, and then the whole formed by the plurality of battery cells 20 is accommodated in the box body; of course, the battery 100 may also be a battery module formed by connecting a plurality of battery cells 20 in series or parallel or series-parallel connection, and a plurality of battery modules are then connected in series or parallel or series-parallel connection to form a whole and are accommodated in a case.

Each battery cell 20 may be a secondary battery or a primary battery; but not limited to, lithium sulfur batteries, sodium ion batteries, or magnesium ion batteries. The battery cell 20 may be in the shape of a cylinder, a flat body, a rectangular parallelepiped, or other shapes, etc.

FIG. 4 is a schematic structural view of an insulating portion according to some embodiments of the present application; fig. 5 is a schematic cross-sectional view of a current collector according to some embodiments of the present application.

Referring to fig. 4 and 5 in combination, in a first aspect, an embodiment of the present application provides a current collector 400, where the current collector 400 includes an insulating portion 40, a positive conductive substrate 51 and a negative conductive substrate 52, the insulating portion 40 includes a first surface 41 and a second surface 42 that are oppositely disposed along a first direction X, and the insulating portion 40 is provided with a through hole 43 penetrating the first surface 41 and the second surface 42; wherein the first direction X is the thickness direction of the insulating portion 40; the positive electrode conductive substrate 51 is disposed on the first surface 41 of the insulating portion 40; the negative electrode conductive base material 52 is disposed on the second surface 42 of the insulating portion 40, and a portion of the positive electrode conductive base material 51 and/or a portion of the negative electrode conductive base material 52 is filled in the through hole 43, and the positive electrode conductive base material 51 and the negative electrode conductive base material 52 are electrically connected through the through hole 43.

The insulating portion 40 may include, but is not limited to, polymers, films, adhesive coatings, and the like. Wherein, the polymer material can comprise polyethylene, polypropylene, polyurethane, polyimide and the like, and has good insulating property and high temperature resistance. The film materials can comprise polyester films, polyamide films, polyimide films and the like, have good insulating property and high temperature resistance, have good flexibility, and can adapt to complex shapes and structures. The material of the adhesive coating may include epoxy resin, polyurethane glue, etc., which have good adhesion and firmly adhere the positive electrode conductive substrate 51 and the negative electrode conductive substrate 52 to the first surface 41 and the second surface 42 of the insulating part 40, respectively.

The positive electrode conductive substrate 51 may be an aluminum foil or a copper foil, and the negative electrode conductive substrate 52 may be a copper foil. A positive electrode active material may be coated on the positive electrode conductive base 51, and a negative electrode active material may be coated on the negative electrode conductive base 52. The positive electrode conductive base 51 and the negative electrode conductive base 52 serve as conductors, and can transmit electric current. The electrolyte can move between the positive electrode conductive substrate 51 and the negative electrode conductive substrate 52, and promote the progress of the electrochemical reaction.

The number of the through holes 43 may be plural, and the plurality of through holes 43 may be arranged in an array on the insulating portion 40, or may be irregularly arranged. The shape of the through hole 43 may be rectangular, square, circular, or the like. The positive electrode conductive base material 51 may be provided only on the first surface 41, the positive electrode conductive base material 51 is not provided in the through hole 43, and the through hole 43 is filled with the material of the negative electrode conductive base material 52. Alternatively, the negative electrode conductive base material 52 may be provided only on the second surface 42, the negative electrode conductive base material 52 is not provided in the through hole 43, and the through hole 43 is entirely filled with the material of the positive electrode conductive base material 51. Or the positive electrode conductive substrate 51 is provided on the first surface 41 and partially filled in the through hole 43; while the negative conductive substrate 52 is disposed on both the second surface 42 and partially fills the through-hole 43, the through-hole 43 has both the material of the positive conductive substrate 51 and the material of the negative conductive substrate 52. The positive electrode conductive base material 51 and the negative electrode conductive base material 52 can be in contact with each other in the through hole 43, and conduction between the positive electrode and the negative electrode is achieved.

In the above-described embodiment, the positive electrode conductive base material 51 and the negative electrode conductive base material 52 are provided on the first surface 41 and the second surface 42 of the insulating portion 40, respectively, so that the current collector 400 can be electrically conducted on both sides. Through the through holes 43 penetrating through the first surface 41 and the second surface 42 are formed in the thickness direction of the insulating part 40, the through holes 43 are filled with the materials of the positive electrode conductive base material 51 and/or the negative electrode conductive base material 52, so that the positive electrode conductive base material 51 and the negative electrode conductive base material 52 are conducted through the through holes 43, conductive connection through the lugs is not needed, additional electrical connection is reduced, the structure is simplified, the space is saved, and the energy density of the battery cell 20 can be improved.

Fig. 6 is a top view of a current collector according to some embodiments of the present application.

As shown in fig. 6, in some embodiments, the insulating portion 40 includes a current collecting region 44 and a sealing region 45 circumferentially disposed around the current collecting region 44, and the positive conductive substrate 51 and the negative conductive substrate 52 respectively cover the current collecting region 44 of the insulating portion 40.

The edge seal region 45 is located at the edge of the insulating portion 40, and no conductive substrate or active material is disposed at the edge seal region 45. For example, the insulating part 40 has a rectangular shape, when the battery cell 20 is prepared, the edge sealing areas 45 of the three sides of each current collector 400 are connected and sealed by hot melting or the like, then electrolyte is injected through one unsealed side edge sealing area 45, the electrolyte enters between each adjacent current collector 400, after the electrolyte injection is completed, the edge sealing area 45 of the last side of each current collector 400 is sealed, and the electrolyte is completely sealed in the electrode assembly 23.

In the above-mentioned scheme, the edge sealing areas 45 between the current collectors 400 can be mutually attached and connected, so that the electrolyte can be sealed, the risk of leakage is reduced, thereby reducing the adverse phenomena of self-discharge, heat generation and the like caused by leakage, and improving the reliability of the battery 100.

In some embodiments, the width of the edge seal region 45 is L1, L1 satisfying the following conditions: l1 is more than or equal to 1mm and less than or equal to 150mm.

The width of the edge seal region 45 refers to the spacing of the edge seal region 45 from the edge of the current collector region 44. For example, the insulating portion 40 is rectangular, and four sides of the insulating portion 40 correspond to four edge sealing areas 45, and the widths of the four edge sealing areas 45 may be the same or different from each other.

Wherein L1 may be any number in the range of 1mm to 150mm. By way of example, L1 may be 1mm, 10mm, 30mm, 50mm, 60mm, 80mm, 100mm, 120mm, 150mm, or the like.

The width of the edge sealing area 45 in the embodiment of the application is suitable, so that the sealing performance of the electrolyte can be guaranteed to a certain extent, the risk of leakage is reduced, and the battery cell 20 can be guaranteed to a certain extent to have higher energy density.

In some embodiments, L1 satisfies the following condition: l1 is more than or equal to 1mm and less than or equal to 15mm. Wherein L1 may be any number in the range of 1mm to 15mm. By way of example, L1 may be 1mm, 2mm, 4mm, 5mm, 6mm, 8mm, 10mm, 12mm, 15mm, or the like. The embodiment of the application further reduces the risk of leakage and ensures that the battery cell 20 has a higher energy density to a certain extent.

Fig. 7 is a schematic cross-sectional view of a current collector according to further embodiments of the present application.

As shown in fig. 7, in some embodiments, the orthographic projection of the positive conductive substrate 51 on the insulating portion 40 is within the range of the orthographic projection of the negative conductive substrate 52 on the insulating portion 40.

In the lithium ion battery 100, there is movement of lithium ions between the positive electrode and the negative electrode. If a problem occurs in the operation of the battery 100, such as extreme temperature or mechanical damage of the battery 100, precipitation of lithium metal on the negative electrode may occur, forming so-called "lithium dendrites" or "lithium branches", which may pass through the electrolyte layer and directly short-circuit the battery 100, i.e., a lithium precipitation phenomenon.

The orthographic projection of the positive electrode conductive substrate 51 on the insulating portion 40 in the embodiment of the present application is the projection of the positive electrode conductive substrate 51 on the insulating portion 40 along the first direction X, and the orthographic projection of the negative electrode conductive substrate 52 on the insulating portion 40 is the projection of the negative electrode conductive substrate 52 on the insulating portion 40 along the first direction X. By "the orthographic projection of the positive electrode conductive substrate 51 on the insulating portion 40 is within the orthographic projection range of the negative electrode conductive substrate 52 on the insulating portion 40" is meant that the orthographic projection of the negative electrode conductive substrate 52 on the insulating portion 40 can encase the orthographic projection of the positive electrode conductive substrate 51 on the insulating portion 40, and the orthographic projection area of the negative electrode conductive substrate 52 on the insulating portion 40 is relatively larger, or the same as the orthographic projection area of the positive electrode conductive substrate 51, direct contact between lithium dendrites and the positive electrode conductive substrate 51 can be reduced, thereby reducing the risk of short circuit.

In the above-described embodiment, the area of the negative electrode conductive base material 52 is set larger, so that the negative electrode conductive base material 52 can be covered, and the lithium deposition phenomenon can be reduced.

In some embodiments, the positive projection of the negative conductive substrate 52 at the insulating portion 40 exceeds the positive projection of the positive conductive substrate 51 at the insulating portion 40 by a width L2, and L2 satisfies the following condition: l2 is more than or equal to 0mm and less than or equal to 20mm.

"width of the positive projection of the negative electrode conductive base material 52 on the insulating portion 40 beyond the positive projection of the positive electrode conductive base material 51 on the insulating portion 40" means: vertical distance from edge of negative electrode conductive substrate 52 to edge of positive electrode conductive substrate 51.

Wherein L2 may be any number in the range of 0mm to 20mm. By way of example, L2 may be 0.1mm, 2mm, 4mm, 5mm, 6mm, 8mm, 10mm, 12mm, 14mm, 15mm, 18mm, 20mm, etc.

The embodiment of the application can reduce the lithium precipitation phenomenon and ensure that the battery cell 20 has higher energy density to a certain extent.

In some embodiments, L2 satisfies the following condition: l2 is more than or equal to 1mm and less than or equal to 10mm.

Wherein L2 may be any number in the range of 1mm to 10mm. By way of example, L2 may be 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, or the like. The present embodiment further reduces the lithium precipitation phenomenon and increases the energy density of the battery cell 20.

Fig. 5 is a schematic cross-sectional view of a current collector according to some embodiments of the present application.

As shown in fig. 5, in some embodiments, the thickness of the portion of the positive electrode conductive base material 51 or the negative electrode conductive base material 52 filled in the through hole 43 is L3, and L3 satisfies the following condition: l3 is more than or equal to 0 μm and less than or equal to 20 μm.

The positive electrode conductive base material 51 may be provided only on the first surface 41, the positive electrode conductive base material 51 is not provided in the through hole 43, and the through hole 43 is filled with the material of the negative electrode conductive base material 52. Alternatively, the negative electrode conductive base material 52 may be provided only on the second surface 42, the negative electrode conductive base material 52 is not provided in the through hole 43, and the through hole 43 is entirely filled with the material of the positive electrode conductive base material 51. Or the positive electrode conductive substrate 51 is provided on the first surface 41 and partially filled in the through hole 43; while the negative conductive substrate 52 is disposed on both the second surface 42 and partially fills the through-hole 43, the through-hole 43 has both the material of the positive conductive substrate 51 and the material of the negative conductive substrate 52.

The thickness of the portion of the positive electrode conductive base material 51 filled in the through hole 43 means: the portion of the positive electrode conductive base material 51 located in the through hole 43 has a thickness in the first direction X. The thickness of the portion of the anode conductive base material 52 filled in the through hole 43 means: the portion of the anode conductive base material 52 located in the through hole 43 has a thickness in the first direction X. Wherein L3 may be any number in the range of 0mm to 20 mm. By way of example, L3 may be 0mm, 1mm, 3mm, 4mm, 6mm, 8mm, 10mm, 12mm, 15mm, 16mm, 18mm, 20mm, etc.

The embodiment of the application can ensure the overcurrent capacity to a certain extent and can improve the energy density of the battery cell 20.

In some embodiments, L3 satisfies the following condition: l3 is more than or equal to 0.5 mu m and less than or equal to 10 mu m. L3 may be any number in the range of 0.5mm to 10 mm. By way of example, L3 may be 0.5mm, 1mm, 1.5mm, 3mm, 3.5mm, 5mm, 6.5mm, 8mm, 8.5mm, 9mm, 9.5mm, 10mm, etc. The embodiment of the application further ensures the overcurrent capacity to a certain extent and can improve the energy density of the battery cell 20.

To some extent, the material of the positive electrode conductive base material 51 includes aluminum, the material of the negative electrode conductive base material 52 includes copper, and the thickness of the portion of the positive electrode conductive base material 51 filled in the through hole 43 is greater than the thickness of the portion of the negative electrode conductive base material 52 filled in the through hole 43.

That is, more material of the positive electrode conductive base material 51 is filled in the through hole 43, or the material of the positive electrode conductive base material 51 is filled in the through hole 43 entirely. Aluminum is lower in cost than copper, and the production cost of the battery cell 20 can be reduced by filling the material of the positive electrode conductive base material 51, which is relatively inexpensive in raw material, in the through hole 43.

As shown in fig. 7, in some embodiments, the thickness L4 of the positive conductive substrate 51 on the first surface 41 or the negative conductive substrate 52 on the second surface 42, L4 satisfies the following condition: l4 is more than or equal to 0.5 μm and less than or equal to 100 μm.

The thickness of the positive electrode conductive substrate 51 on the first surface 41 means: the thickness of the positive electrode conductive base material 51 in the first direction X. The thickness of the negative conductive substrate 52 on the second surface 42 is: the thickness of the anode conductive base material 52 in the second direction Y. Wherein L4 may be any number in the range of 0.5mm to 100 mm. By way of example, L4 may be 0.5mm, 10mm, 20mm, 30mm, 40mm, 50mm, 60mm, 70mm, 80mm, 90mm, 100mm, or the like.

In some embodiments, L4 satisfies the following condition: l4 is more than or equal to 0.5 mu m and less than or equal to 10 mu m. Wherein L4 may be any number in the range of 0.5mm to 10 mm. By way of example, L4 may be 0.5mm, 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc.

The embodiment of the application further ensures the overcurrent capacity to a certain extent and can improve the energy density of the battery cell 20.

Fig. 8 is a schematic cross-sectional view of a pole piece according to some embodiments of the present application.

As shown in fig. 8, in a second aspect, the present embodiment provides a pole piece 500, including a positive electrode active layer 61, a negative electrode active layer 62, and the current collector 400 of any of the foregoing embodiments, where the positive electrode active layer 61 is disposed on a side of the positive electrode conductive substrate 51 facing away from the insulating portion 40; the anode active layer 62 is disposed on a side of the anode conductive substrate 52 facing away from the insulating portion 40.

The positive electrode active layer 61 is coated on the surface of the positive electrode conductive substrate 51, and the material of the positive electrode active layer 61 may include lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate, or the like. The anode active layer 62 is coated on the surface of the anode conductive substrate 52, and the anode active layer 62 may be made of carbon, silicon, or the like.

Because the pole piece 500 adopts all the technical solutions of all the embodiments, at least has all the beneficial effects brought by the technical solutions of the embodiments, and the description is omitted herein.

Fig. 9 is an exploded schematic view of a battery cell according to some embodiments of the present application.

As shown in fig. 9, in a third aspect, an embodiment of the present application provides a battery cell 20 including a case 22 and an electrode assembly 23, wherein an electrolyte is disposed in the case 22; the electrode assembly 23 is accommodated in the case 22, and the electrode assembly 23 includes a plurality of separator films 24 and a plurality of pole pieces 500 of any of the above embodiments, with the separator films 24 being provided between adjacent pole pieces 500.

The pole pieces 500 and the separator 24 are alternately arranged in sequence along the first direction X. The material of the separator 24 may be PP (polypropylene) or PE (polyethylene). The separator 24 can prevent direct current flow but allows transfer of lithium ions.

Since the battery cell 20 adopts all the technical solutions of all the embodiments, at least the technical solutions of the embodiments have all the beneficial effects brought by the technical solutions of the embodiments, and are not described in detail herein.

In some embodiments, the insulating portion 40 includes a current collecting region 44 and a sealing edge region 45 circumferentially disposed around the current collecting region 44, and the positive conductive substrate 51 and the negative conductive substrate 52 respectively cover the current collecting region 44 of the insulating portion 40; the edge seal areas 45 of the plurality of pole pieces 500 are connected to each other with the electrolyte sealed between the pole pieces 500.

In some embodiments, the case 22 includes first and second sub-cases 25 and 26 disposed at opposite sides of the electrode assembly 23 in the first direction X, respectively; the first sub-case 25 includes a first conductive part 251 and first sealing parts 252 provided at both ends of the first conductive part 251 in the second direction Y; the second sub-case 26 includes a second conductive part 261 and second sealing parts 262 disposed at both ends of the second conductive part 261 in the second direction Y; the first and second conductive parts 251 and 261 are electrically connected with the electrode assembly 23, respectively, and the first and second sealing parts 252 and 262 are hermetically connected in one-to-one correspondence; wherein the second direction Y is disposed intersecting the first direction X.

In the first direction X, the side of the electrode assembly 23 adjacent to the electrode tab 500 of the first sub-case 25 is not coated with an active material and is directly connected to the first conductive part 251 of the first sub-case 25 through a conductive base material. In the first direction X, the electrode assembly 23 is directly connected to the second conductive part 261 of the second sub-case 26 through the conductive base material without coating the active material on the side of the electrode assembly 23 adjacent to the electrode tab 500 of the second sub-case 26. For example, the first sub-case 25 is positioned on the left side, the second sub-case 26 is positioned on the right side, only the positive electrode conductive base material 51 is provided on the surface of the pole piece 500 positioned on the left side facing the first sub-case 25, the positive electrode active layer 61 is not provided, and the positive electrode conductive base material 51 of the pole piece 500 is directly connected to the first conductive portion 251; only the negative electrode conductive base material 52 is provided on the side of the electrode sheet 500 located on the right side facing the second sub-case 26, and the negative electrode active layer 62 is not provided, and the negative electrode conductive base material 52 of the electrode sheet 500 is directly connected to the second conductive portion 261.

The second direction Y may be a height direction of the battery cell 20, and the first sealing part 252 and the second sealing part 262 are formed of an insulating material for insulation and sealing of the entire battery cell 20. Illustratively, the first sealing part 252 is disposed at the upper end and the lower end of the first conductive part 251, the second sealing part 262 is disposed at the upper end and the lower end of the second conductive part 261, and the first sealing part 252 at the upper end of the first conductive part 251 and the first sealing part 252 at the upper end of the second conductive part 261 can be connected in a sealing manner by a heat-melting process or the like; the first sealing portion 252 at the lower end of the first conductive portion 251 and the second sealing portion 262 at the lower end of the second conductive portion 261 may be hermetically connected by a heat-fusing process or the like.

In the above-mentioned scheme, since the edges of the electrode assembly 23 are all hermetically connected through the edge sealing regions 45 of the electrode sheet 500, the embodiment of the present application provides the first and second sub-cases 25 and 26 only at both sides of the electrode assembly 23. The electric power of the battery cell 20 is output or input through the first conductive part 251 and the second conductive part 261. By sealing the first sealing part 252 of the first sub-case 25 and the second sealing part 262 of the second sub-case 26, which are disposed opposite to each other, the battery cell 20 can be sealed, and thus, space can be saved and the energy density of the battery 100 can be improved.

FIG. 9 is an exploded schematic view of a battery cell according to some embodiments of the present application; fig. 10 is a schematic structural view of a battery cell according to some embodiments of the present application.

Referring to fig. 9 and 10 in combination, in some embodiments, a first groove 271 is disposed at one end of the first conductive portion 251 along the second direction Y, and a first protrusion 272 matching the first groove 271 is disposed at the other end; and/or, one end of the second conductive part 261 in the second direction Y is provided with a second groove 281, and the other end is provided with a second part matched with the second groove 281.

The matching of the first groove 271 and the first protrusion 272 means that: the first groove 271 and the first protrusion 272 are matched in size and shape with each other, and the first protrusion 272 can be just inserted into the first groove 271. Similarly, the second recess 281 and the second protrusion 282 being matched means that: the second recess 281 and the second protrusion 282 are sized and shaped to match each other, and the second protrusion 282 can be just inserted into the second recess 281. Illustratively, after the first sealing part 252 is sealingly connected with the second sealing part 262, the first protrusion 272 of the previous battery cell 20 may be inserted into the first groove 271 of the next battery cell 20; and/or, the second protrusion 282 of the previous battery cell 20 is inserted into the second recess 281 of the next battery cell 20, so that the electrical connection between the battery cells 20 is achieved.

In the above-described embodiment, the parallel connection between the battery cells 20 can be achieved by inserting the first convex portions 272 of the battery cells 20 into the first concave portions 291 of the adjacent battery cells 20 and/or inserting the second convex portions 282 of the battery cells 20 into the second concave portions 291 of the adjacent battery cells 20.

In some embodiments, a side of the first conductive part 251 facing away from the electrode assembly 23 is concavely disposed with respect to the first sealing part 252, forming a recess 291; the second conductive part 261 is provided in a convex shape with respect to the second sealing part 262 at a side facing away from the electrode assembly 23, forming a ridge part 292 matching the recess 291.

Illustratively, the first sub-case 25 is positioned on the left side, the second sub-case 26 is positioned on the right side, and the first sealing portion 252 is disposed at the end portion disposed on the left side of the first conductive portion 251, so that the first conductive portion 251 is disposed concavely rightward with respect to the first sealing portion 252, i.e., a recess 291 is formed. The second sealing portion 262 is provided at the right end of the second conductive portion 261, and the second conductive portion 261 protrudes rightward with respect to the second sealing portion 262, that is, a ridge portion 292 is formed. In assembling the battery 100, the convex portion of the previous battery cell 20 may be inserted into the concave portion 291 of the next battery cell 20, thereby achieving electrical connection between the battery cells 20.

In the above-described configuration, the series connection between the battery cells 20 can be achieved by inserting the ridge 292 of the battery cell 20 into the recess 291 of the adjacent battery cell 20.

In a fourth aspect, the present examples provide a battery 100 comprising a battery cell 20 according to any of the above embodiments.

In a fifth aspect, an embodiment of the present application provides an electrical device, including the battery cell 20 or the battery 100 of any one of the foregoing embodiments, where the battery cell 20 or the battery 100 is used to provide electrical energy.

According to some embodiments of the present application, there is provided a current collector 400, the current collector 400 including an insulating portion 40, a positive electrode conductive base material 51, and a negative electrode conductive base material 52, the insulating portion 40 including a first surface 41 and a second surface 42 disposed opposite to each other in a first direction X, the insulating portion 40 being provided with a through hole 43 penetrating the first surface 41 and the second surface 42; wherein the first direction X is the thickness direction of the insulating portion 40; the positive electrode conductive substrate 51 is disposed on the first surface 41 of the insulating portion 40; the negative electrode conductive base material 52 is disposed on the second surface 42 of the insulating portion 40, and a portion of the positive electrode conductive base material 51 and/or a portion of the negative electrode conductive base material 52 is filled in the through hole 43, and the positive electrode conductive base material 51 and the negative electrode conductive base material 52 are electrically connected through the through hole 43. The insulating portion 40 includes a current collecting region 44, and a sealing region 45 circumferentially surrounding the current collecting region 44, and the positive electrode conductive substrate 51 and the negative electrode conductive substrate 52 respectively cover the current collecting region 44 of the insulating portion 40.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the embodiments, and are intended to be included within the scope of the claims and description. In particular, the technical features mentioned in the respective embodiments may be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions falling within the scope of the claims.

Claims

1. A current collector, comprising:

an insulating part including a first surface and a second surface disposed opposite to each other in a first direction, the insulating part being provided with a through hole penetrating the first surface and the second surface; wherein the first direction is a thickness direction of the insulating portion;

A positive electrode conductive base material disposed on the first surface of the insulating portion;

the negative electrode conductive base material is arranged on the second surface of the insulation part, part of the positive electrode conductive base material and/or part of the negative electrode conductive base material is/are filled in the through hole, and the positive electrode conductive base material and the negative electrode conductive base material are conducted through the through hole.

2. The current collector of claim 1, wherein the insulating portion comprises a current collecting region and a sealing region circumferentially disposed around the current collecting region, the positive and negative conductive substrates respectively covering the current collecting region of the insulating portion.

3. The current collector of claim 2, wherein the edge seal has a width L1, the L1 satisfying the following condition: l1 is more than or equal to 1mm and less than or equal to 150mm.

4. A current collector according to claim 3, wherein L1 satisfies the following condition: l1 is more than or equal to 1mm and less than or equal to 15mm.

5. The current collector of claim 1, wherein an orthographic projection of the positive conductive substrate at the insulating portion is within an orthographic projection of the negative conductive substrate at the insulating portion.

6. The current collector of claim 5, wherein the positive projection of the negative conductive substrate at the insulating portion exceeds the positive projection of the positive conductive substrate at the insulating portion by a width L2, the L2 satisfying the following condition: l2 is more than or equal to 0mm and less than or equal to 20mm.

7. The current collector of claim 6, wherein L2 satisfies the following condition: l2 is more than or equal to 1mm and less than or equal to 10mm.

8. The current collector according to claim 1, wherein a thickness of a portion of the positive electrode conductive base material or the negative electrode conductive base material filled in the through hole is L3, the L3 satisfying the following condition: l3 is more than or equal to 0 μm and less than or equal to 20 μm.

9. The current collector of claim 8, wherein L3 satisfies the following condition: l3 is more than or equal to 0.5 mu m and less than or equal to 10 mu m.

10. The current collector of claim 1, wherein the material of the positive electrode conductive substrate comprises aluminum and the material of the negative electrode conductive substrate comprises copper, and the thickness of the positive electrode conductive substrate filled in the portion of the through hole is greater than the thickness of the negative electrode conductive substrate filled in the portion of the through hole.

11. The current collector of claim 1, wherein the positive conductive substrate is located on the first surface or the negative conductive substrate is located on the second surface with a thickness L4, the L4 satisfying the following condition: l4 is more than or equal to 0.5 μm and less than or equal to 100 μm.

12. The current collector of claim 11, wherein L4 satisfies the following condition: l4 is more than or equal to 0.5 mu m and less than or equal to 10 mu m.

13. A pole piece, comprising:

a current collector according to any one of claims 1-12;

the positive electrode active layer is arranged on one side of the positive electrode conductive base material, which is away from the insulating part;

and the negative electrode active layer is arranged on one side of the negative electrode conductive base material, which is away from the insulation part.

14. A battery cell, comprising:

a housing in which an electrolyte is provided;

an electrode assembly housed within the housing, the electrode assembly comprising a plurality of separator films and a plurality of pole pieces according to claim 13, the separator films being disposed between adjacent pole pieces.

15. The battery cell of claim 14, wherein the insulating portion comprises a current collecting region and a sealing region circumferentially disposed around the current collecting region, the positive and negative conductive substrates respectively covering the current collecting region of the insulating portion;

the edge sealing areas of the plurality of pole pieces are mutually connected, and the electrolyte is sealed between the pole pieces.

16. The battery cell according to claim 15, wherein the case includes a first sub-case and a second sub-case disposed at opposite sides of the electrode assembly in the first direction, respectively;

The first sub-shell comprises a first conductive part and first sealing parts arranged at two ends of the first conductive part along a second direction; the second sub-shell comprises a second conductive part and second sealing parts arranged at two ends of the second conductive part along a second direction; the first conductive part and the second conductive part are respectively and electrically connected with the electrode assembly, and the first sealing part and the second sealing part are in one-to-one corresponding sealing connection;

wherein the second direction is arranged to intersect the first direction.

17. The battery cell according to claim 16, wherein one end of the first conductive part in the second direction is provided with a first groove, and the other end is provided with a first protrusion matched with the first groove; and/or the number of the groups of groups,

one end of the second conductive part along the second direction is provided with a second groove, and the other end of the second conductive part is provided with a second part matched with the second groove.

18. The battery cell of claim 16, wherein a side of the first conductive portion facing away from the electrode assembly is recessed relative to the first sealing portion to form a recess;

the side of the second conductive part, which is away from the electrode assembly, is convexly arranged relative to the second sealing part to form a bulge matched with the concave part.

19. A battery comprising a cell according to any one of claims 14-18.

20. An electrical device comprising a cell according to any one of claims 14 to 18 or a battery according to claim 19, the cell or battery being adapted to provide electrical energy.