WO2023137597A1

WO2023137597A1 - Battery

Info

Publication number: WO2023137597A1
Application number: PCT/CN2022/072615
Authority: WO
Inventors: 魏文飞; 郭富荣; 张文轩; 吴莉平; 谭忠; 宋江涛
Original assignee: 珠海冠宇电池股份有限公司
Priority date: 2022-01-18
Filing date: 2022-01-18
Publication date: 2023-07-27

Abstract

Embodiments of the present application relate to the technical field of batteries, and specifically relates to a battery, being aimed at solving the technical problem of low battery energy density caused due to the fact that the size of batteries connected in series is large. According to the battery provided by the embodiments of the present application, the interior of a packaging film shell is divided by an isolation layer into a first cavity and a second cavity that are independent; a first battery cell is arranged in the first cavity; a second battery cell is located in the second cavity; a first positive tab and a first negative tab extending out of the packaging film shell are arranged on the first battery cell; a second positive tab and a second negative tab extending out of the packaging film shell are arranged on the second battery cell; and the first negative tab is electrically connected to the second positive tab. According to the embodiments, the first battery cell and the second battery cell are arranged in one packaging film shell, and compared with the mode that each battery cell is arranged in one packaging film shell, the use amount of the packaging film shell can be reduced, so that the occupied size of the packaging film shell is reduced, the size of the battery is further reduced, and the energy density of the battery is increased.

Description

Battery

technical field

The embodiments of the present application belong to the technical field of batteries, and specifically relate to a battery.

Background technique

The battery uses a carbon material as the negative electrode and a lithium-containing compound as the positive electrode. Under the action of the electrolyte, lithium ions are reciprocally intercalated and deintercalated between the positive electrode and the negative electrode to realize the charging and discharging of the battery. Due to the advantages of environmental protection and long service life, batteries are widely used in various industries such as computers and electric vehicles.

In the related art, in order to increase the output voltage of the battery, a single battery cell is usually packaged in an encapsulating film case, and then the packaged batteries are connected in series to increase the output voltage of the battery.

However, the series-connected batteries in the related art include a plurality of encapsulating membrane shells, which makes the volume of the series-connected batteries larger, which in turn leads to lower energy density of the batteries.

Contents of the invention

The main purpose of the embodiment of the present application is to provide a battery, aiming at solving the technical problem in the related art that the series-connected battery includes a plurality of encapsulating membrane cases, resulting in a larger volume of the series-connected battery.

To achieve the above purpose, the battery provided in the embodiment of the present application includes: an encapsulating membrane case, and a first cell and a second cell located in the encapsulating membrane case;

An isolation layer is provided in the packaging film case, and the isolation layer divides the packaging film case into two independent first cavities and second cavities, the first cell is arranged in the first cavity, and the second cell is arranged in the second cavity;

The first electric core has a first positive tab and a first negative tab extending out of the packaging film;

The second electric core has a second positive tab and a second negative tab extending out of the packaging film;

The first negative tab is electrically connected to the second positive tab.

On the basis of the above technical solution, the embodiment of the present application can also be improved as follows:

In some embodiments that may include the above-mentioned embodiments, the first battery cell and the second battery cell are arranged side by side.

In some embodiments that may include the above-mentioned embodiments, the isolation layer is provided with a first groove and a second groove, the first cell is disposed in the first groove, the second cell is disposed in the second groove, and the depth direction of the first groove and the depth direction of the second groove are perpendicular to the isolation layer.

In some embodiments that may include the above embodiments, a groove wall of the first groove close to the second groove communicates with a groove wall of the second groove close to the first groove.

In some embodiments that may include the above embodiments, the groove bottom of the first groove is located on the first side of the isolation layer, the groove bottom of the second groove is located on the second side of the isolation layer, and the first side and the second side are opposite to each other.

In some embodiments that may include the above embodiments, the groove depth of the first groove is greater than or equal to half of the thickness of the first cell; and/or, the groove depth of the second groove is greater than or equal to half of the thickness of the second cell.

In some embodiments that may include the above-mentioned embodiments, the length of the isolation layer is less than or equal to the length of the packaging membrane; and/or, the width of the isolation layer is less than or equal to the width of the packaging membrane.

In some embodiments that may include the above-mentioned embodiments, the battery further includes a connector, and the connector is connected to both the first negative tab and the second positive tab.

In some embodiments that may include the above-mentioned embodiments, the packaging film case includes a first cover plate and a second cover plate, a first accommodating groove is provided on one side of the first cover plate, the first battery cell and the second battery cell are both accommodated in the first accommodating groove, and the second cover plate covers the first cover plate and closes the first accommodating groove.

In some embodiments that may include the above-mentioned embodiments, the packaging film case includes a first cover plate and a second cover plate, a first accommodating groove is provided on one side of the first cover plate, a second accommodating groove is provided on one side of the second cover plate, the second cover plate covers the first cover plate, and the first accommodating groove and the second accommodating groove are surrounded by accommodating grooves for accommodating the first cell and the second cell.

In some embodiments that may include the above-mentioned embodiments, the encapsulation film case further includes a first sealing portion that seals the first positive tab and the first negative tab, and a second sealing portion that seals the second positive tab and the second negative tab;

The first negative tab includes a first bent portion bent to the first sealing portion; the second positive tab includes a second bent portion bent to the second sealing portion; the connectors respectively connect the first bent portion and the second bent portion.

In some embodiments that may include the above embodiments, the battery further includes a protective adhesive layer, and the protective adhesive layer covers the connector, the first sealing portion, the second sealing portion, the first bending portion, and the second bending portion.

In some embodiments that may include the above-mentioned embodiments, the first electric core has a wound structure or a laminated structure; the second electric core has a wound structure or a laminated structure.

In the battery provided in the embodiment of the present application, the inside of the packaging film case is divided into independent first cavity and second cavity by the isolation layer. The first cell is arranged in the first cavity, and the second cell is located in the second cavity. The first cell has a first positive tab and a first negative tab extending out of the packaging case; the second cell has a second positive tab and a second negative tab extending out of the packaging case, and the first negative tab is electrically connected to the second positive tab. Compared with setting the battery cells in a packaging membrane case, the amount of the packaging membrane case can be reduced, so as to reduce the volume occupied by the packaging membrane case, thereby reducing the volume of the battery and improving the energy density of the battery.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments or related technologies. Obviously, the accompanying drawings in the following description are only some embodiments of the application. For those of ordinary skill in the art, other drawings can also be obtained according to the structures shown in these drawings without creative work.

Fig. 1 is the top view of the lithium ion battery that the embodiment of the present application provides;

Fig. 2 is the explosion diagram of the lithium ion battery that the embodiment of the present application provides;

Fig. 3 is the sectional view of the A-A direction of the lithium-ion battery provided by the embodiment of the present application;

FIG. 4 is a schematic structural view of a separator layer of a lithium-ion battery provided in an embodiment of the present application;

Fig. 5a is a structural schematic diagram 1 of the first positive electrode sheet and the first negative electrode sheet constituting the first winding core in the lithium ion battery provided by the embodiment of the present application;

Figure 5b is a schematic diagram of the structure of the first winding core in the lithium-ion battery provided by the embodiment of the present application;

Fig. 6a is a structural schematic diagram 2 of the first positive electrode sheet and the first negative electrode sheet constituting the first winding core in the lithium ion battery provided by the embodiment of the present application;

Fig. 6b is the second structural schematic diagram of the first winding core in the lithium-ion battery provided by the embodiment of the present application;

Fig. 7a is a structural schematic diagram 1 of the second positive electrode sheet and the second negative electrode sheet constituting the second winding core in the lithium ion battery provided by the embodiment of the present application;

Fig. 7b is a structural schematic diagram 1 of the second winding core in the lithium-ion battery provided by the embodiment of the present application;

Fig. 8a is a schematic structural view of the first positive electrode sheet and the first negative electrode sheet of the first winding core formed by stacking in the lithium ion battery provided by the embodiment of the present application;

Fig. 8b is an exploded view of the first winding core formed by stacking in the lithium ion battery provided by the embodiment of the present application.

Explanation of reference signs:

10-the first cell; 110-the first positive plate;

111-the first positive pole ear; 120-the first negative pole piece;

121-the first negative pole ear; 130-positive electrode material;

140-negative electrode material;

20-the second cell; 211-the second positive ear;

221-the second negative pole ear;

30-isolation layer; 310-the first groove;

320 - the second groove;

40-connector;

50-encapsulation membrane shell; 510-the first cover plate;

511-the first accommodation slot; 512-the first packaging skirt;

520 - Second cover plate.

By means of the above drawings, specific embodiments of the present application have been shown, which will be described in more detail hereinafter. These drawings and text descriptions are not intended to limit the scope of the concept of the application in any way, but to illustrate the concept of the application for those skilled in the art by referring to specific embodiments.

Detailed ways

In order to increase the output voltage of the battery, in related technologies, a single battery cell is often packaged in a packaging membrane, and then the packaged batteries are connected in series to increase the output voltage of the battery. There is a space between the packaging edge of the packaging membrane and the battery to set up a sealing structure to prevent the electrolyte in the battery from leaking. The volume of the batteries connected in series is larger, which in turn leads to lower energy density of the batteries.

In view of this, in the battery provided in the embodiment of the present application, the packaging membrane case is divided into independent first cavity and second cavity by the isolation layer, the first battery cell is located in the first cavity, the second battery cell is located in the second cavity, the first battery cell and the second battery cell are arranged in one packaging membrane case, and only the surroundings of one packaging membrane case need to be sealed and packaged during the packaging process, which reduces the number of packaging membrane cases used, saves reserved packaging space, reduces the volume of the battery, and improves the energy density of the battery.

The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of them. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

As shown in FIG. 1 and FIG. 2 , the battery provided in the embodiment of the present application includes: an encapsulating membrane case 50 , and a first cell 10 and a second cell 20 located in the encapsulating membrane case 50 .

As shown in Figure 5a and Figure 5b, wherein the first cell 10 has a first positive tab 111 and a first negative tab 121, specifically, the first cell 10 includes a first positive tab 110 and a first negative tab 120, the first positive tab 110 includes a positive current collector, the positive current collector is coated with a positive electrode material 130, the positive current collector is also provided with a first positive tab 111, the first positive tab 111 is a positive interface connected to an external circuit; the first negative tab 120 includes a negative electrode collector, on which a negative electrode material 140 is coated, and a first negative electrode ear 121 is also arranged on the negative electrode collector, and the first negative electrode ear 121 is a negative electrode interface.

Wherein, continue referring to FIG. 5 a, the positive electrode current collector is used to carry the active positive electrode material 130, and the negative electrode current collector is used to carry the active negative electrode material 140. At the same time, the positive electrode current collector and the negative electrode current collector can collect the electrons generated by the electrochemical reaction and lead them to the external circuit; the material of the positive electrode current collector can be aluminum foil, and the material of the negative electrode current collector can be copper foil.

The positive electrode material 130 provides a lithium ion source for the battery, and the positive electrode material 130 is a lithium ion compound. Exemplarily, the positive electrode material 130 can be lithium cobalt oxide, a ternary material or lithium iron phosphate; the negative electrode material 140 is the main substance that constitutes the negative electrode reaction, and the negative electrode material 140 can be graphite, mesocarbon microspheres, silicon-based materials, etc.

As shown in FIG. 5a and FIG. 5b , a separator layer is provided between the first positive electrode sheet 110 and the first negative electrode sheet 120 , and the first cell 10 is formed by winding the first positive electrode sheet 110 , the first negative electrode sheet 120 and the separator layer.

During operation, an electrolyte solution is filled between the first positive electrode sheet 110 and the first negative electrode sheet 120. When the battery is charged, the battery is connected to an external power source through the first positive electrode ear 111 and the first negative electrode ear 121. The positive electrode material 130 on the first positive electrode sheet 110 is ionized into lithium ions and electrons in the electrolyte. The potential of the positive electrode is high, and the electrons flow from the positive electrode current collector to the negative electrode collector through an external circuit. Lithium ions are free in the electrolyte and enter the negative electrode through the diaphragm layer. Lithium ions can be embedded in the porous negative electrode material 140, and the higher the embedded lithium ions, the higher the charging capacity; when the battery is discharged, the potential of the negative electrode is high, and the lithium ions embedded in the negative electrode material 140 are deintercalated from the negative electrode material 140, and then return to the positive electrode through the separator layer, and at the same time, the electrons also return to the positive electrode through the external circuit, and the directional movement of the electrons forms a current to supply power for the external circuit.

As shown in FIGS. 7a and 7b, in this embodiment, the second cell 20 has a second positive tab 211 and a second negative tab 221; specifically, the second cell 20 includes a second positive tab and a second negative tab, the second positive tab is provided with a second positive tab 211, and the second negative tab is provided with a second negative tab 221. The structure and working principle of the second cell 20 are the same as those of the first cell 10, and will not be repeated here.

As shown in Figures 1 and 2, the first battery cell 10 and the second battery cell 20 in the embodiment of the present application may be batteries with the same structure and size; of course, in other embodiments, the first battery cell 10 and the second battery cell 20 may also be batteries of different shapes and sizes, which is not limited in the embodiment of the present application.

In this embodiment, as shown in FIGS. 1-3 , the packaging film case 50 is used to package the first battery cell 10 and the second battery cell 20 to realize the assembly and protection of the first battery cell 10 and the second battery cell 20, wherein the packaging film case 50 may be an aluminum-plastic film. Exemplarily, the packaging film case 50 may include a PP layer, and an aluminum layer and a nylon layer sequentially arranged on the PP layer. In this embodiment, the packaging film case 50 is provided with an isolation layer 30, and the isolation layer 30 divides the packaging film case 50 into two independent first cavities and second cavities. The first cell 10 is disposed in the first cavity, and the second cell 20 is disposed in the second cavity. The first cavity and the second cavity are sealed to prevent leakage of the electrolyte in the first cavity or the second cavity.

Wherein, as shown in FIG. 1 , the isolation layer 30 is used to isolate the first cavity and the second cavity, so as to prevent the electrolyte in the first cavity and the electrolyte in the second cavity from leaking each other, thereby affecting the power supply of the first cell 10 and the second cell 20 .

The material of the isolation layer 30 may include an insulating material. Exemplarily, the material of the isolation layer 30 is polyethylene terephthalate or polyurethane, and of course other polyester organic substances may also be used.

In some embodiments, the thickness of the isolation layer 30 can be 30 μm-400 μm, for example, the thickness is 30 μm, 100 μm, 400 μm, of course, in order to further reduce the thickness of the battery, the thickness of the isolation layer 30 can also be 30 μm-80 μm, for example, the thickness is 30 μm, 50 μm, 80 μm.

In this embodiment, as shown in FIG. 1 , the first cell 10 has a first positive tab 111 and a first negative tab 121 extending out of the encapsulating film case 50; the second cell 20 has a second positive tab 211 and a second negative tab 221 extending out of the encapsulating film case 50; the first negative tab 121 is electrically connected to the second positive tab 211, so that the operation space when the first negative tab 121 is connected to the second positive tab 211 is relatively large, thereby facilitating battery installation. make.

During installation, as shown in FIGS. 1-3 , the first battery cell 10 is installed in the first cavity, and the second battery cell 20 is installed in the second cavity. The first negative electrode ear 121 of the first battery cell 10 protrudes out of the encapsulating film case 50 , and the second positive electrode ear 211 of the second battery cell 20 extends out of the encapsulating film shell 50 .

In the battery provided in the embodiment of the present application, the packaging film case 50 is divided into independent first cavity and second cavity by the isolation layer 30. The first battery cell 10 is arranged in the first cavity, and the second battery cell 20 is located in the second cavity. 1 is electrically connected to the second positive electrode ear 211. In this embodiment, the first battery cell 10 and the second battery cell 20 are arranged in one packaging membrane case 50. Compared with each battery cell being arranged in one packaging membrane case 50, the consumption of the packaging membrane case 50 can be reduced, so as to reduce the volume occupied by the packaging membrane case 50, thereby reducing the volume of the battery and improving the energy density of the battery.

In some realizable embodiments, the first battery cell 10 can be stacked on the second battery cell 20 , that is, the first cavity is set on the second cavity.

In some other realizable embodiments, as shown in FIGS. 1-3 , the first battery cell 10 and the second battery cell 20 are arranged side by side, that is, the first cavity and the second cavity are arranged side by side, so that the thickness of the battery is only the thickness of one battery cell, and compared with the embodiment in which the first battery cell 10 is arranged on the second battery cell 20, the thickness of the battery is reduced.

In some embodiments, as shown in FIG. 2 and FIG. 3 , the isolation layer 30 is provided with a first groove 310 and a second groove 320, the first cell 10 is arranged in the first groove 310, the second cell 20 is arranged in the second groove 320, the first groove 310 makes the first cell 10 stably installed in the first cavity, and the second groove 320 makes the second cell 20 stably installed in the second cavity; the depth direction of the first groove 310 and the depth direction of the second groove 320 are perpendicular to the isolation layer 30 That is to say, the first groove 310 and the second groove 320 are arranged side by side, so as to match the arrangement of the first battery cell 10 and the second battery cell 20 so as to reduce the thickness of the battery.

In some embodiments, as shown in FIG. 3 and FIG. 4 , the groove wall of the first groove close to the second groove communicates with the groove wall of the second groove close to the first groove, that is to say, the first groove and the second groove share a side wall, so that the length of the battery is reduced, and the energy density of the battery is further improved.

It should be noted that, in the battery in the embodiment of the present application, the direction in which the tabs protrude is the width direction, and the direction in which the first cell 10 and the second cell 20 extend side by side is the length direction.

In some realizable embodiments, the isolation layer 30 includes a first side and a second side oppositely arranged, and the groove bottom of the first groove 310 and the groove bottom of the second groove 320 can be located on the first side at the same time, or can be located on the second side at the same time, that is to say, the notch of the first groove 310 and the notch of the second groove 320 are arranged in the same direction.

2-4, the groove bottom of the first groove 310 is located on the first side of the isolation layer 30, the groove bottom of the second groove 320 is located on the second side of the isolation layer 30, and the first side and the second side are oppositely arranged, that is to say, as shown in FIG. In the embodiment in which the opening of the first groove 310 and the opening of the second groove 320 are arranged in the same direction, the junction of the first groove 310 and the second groove 320 needs to bend the isolation layer 30 by 180°, that is to say, the common groove wall of the first groove 310 and the second groove 320 is composed of two layers of isolation layers 30. Therefore, in this embodiment, the forming method of the first groove 310 and the second groove 320 is simpler, and the common groove wall is composed of a layer of isolation layer 30, which can reduce the distance between the batteries along the tiling direction. Further reduce the volume of the battery.

It is worth noting that the first groove 310 and the second groove 320 can be formed by stamping, specifically, the first groove 310 is formed by stamping on the first side of the isolation layer 30 using the first stamping die, and the second groove 320 is formed by stamping on the second side of the isolation layer 30 by using the second stamping die; of course, other methods such as molding can also be used, which are not limited in the embodiments of the present application.

In some embodiments, as shown in FIG. 3 and FIG. 4 , the groove depth of the first groove 310 is greater than or equal to half of the thickness of the first battery cell 10 , so that the first battery cell 10 is placed in the first groove 310 to avoid wrinkles around the first groove 310 due to the thinner thickness of the isolation layer 30 .

3 and 4, the groove depth of the second groove 320 is greater than or equal to half of the depth of the second cell 20. Such arrangement avoids the phenomenon of wrinkles around the second groove 320 due to the thinner thickness of the isolation layer 30 when the second cell 20 is placed in the second groove 320.

In this embodiment, the groove depth of the first groove 310 can be set to be greater than or equal to half the thickness of the first battery cell 10 , and the groove depth of the second groove 320 can be set to be greater than or equal to half the depth of the second battery core 20 ;

In some embodiments, the length of the isolation layer 30 is less than or equal to the length of the packaging membrane case 50 , that is, the length of the isolation layer 30 does not exceed the length of the packaging membrane case 50 , so as to reduce the length of the battery.

In some other embodiments, the width of the isolation layer 30 is less than or equal to the width of the encapsulation film case 50 , that is, the width of the isolation layer 30 does not exceed the width of the encapsulation film case 50 , so as to reduce the width of the battery.

In some embodiments, the distance between the first negative tab 121 and the second positive tab 211 is small, the first negative tab 121 can directly contact the second positive tab 211 , and the first negative tab 121 can be welded on the second positive tab 211 .

In some other embodiments, as shown in FIG. 1 and FIG. 2 , the battery further includes a connector 40, which is respectively connected to the first negative tab 121 and the second positive tab 211, and the connection with the connector 40 reduces the requirement for the distance between the first negative tab 121 and the second positive tab 211, and facilitates the connection between the first negative tab 121 and the second positive tab 211.

The connecting member 40 is a conductor, and the material may be nickel, titanium or other conductive materials, which is not limited in this embodiment.

Exemplarily, the connector 40 includes a conductive sheet, which is welded to both the first negative tab 121 and the second positive tab 211 , and the first negative tab 121 and the second positive tab 211 can be conveniently connected by using the conductive sheet.

In some embodiments, as shown in FIG. 1 and FIG. 3 , the encapsulating film case 50 includes a first cover plate 510 and a second cover plate 520. One side of the first cover plate 510 is provided with a first accommodating groove 511. Both the first cell 10 and the second cell 20 are accommodated in the first accommodating groove 511. The second cover plate 520 covers the first cover plate 510 and closes the first accommodating groove 511. And the packaging of the second electric core 20.

In some other embodiments, as shown in FIGS. 1-3 , the packaging film case 50 includes a first cover plate 510 and a second cover plate 520. One side of the first cover plate 510 is provided with a first accommodation groove 511, and one side of the second cover plate 520 is provided with a second accommodation groove. 6mm) packaging of the first electric core 10 or the second electric core 20.

In some embodiments, the packaging film case 50 further includes a first sealing portion that seals the first positive tab 111 and the first negative tab 121 and a second sealing portion that seals the second positive tab 211 and the second negative tab 221. The first sealing portion and the second sealing portion are used to prevent the electrolyte from leaking at the junction of the tabs.

Wherein, the first negative tab 121 includes a first bending portion bent to the first sealing portion; the second positive tab 211 includes a second bending portion bent to the second sealing portion; the connector 40 is respectively connected to the first bending portion and the second bending portion, that is to say, by bending the first bending portion and the second bending portion, the first negative tab 121 and the second positive tab 211 are connected to the connector near or attached to the packaging film case 50, so as to reduce the width of the lithium battery and save the occupancy in the battery pack process Space, thereby increasing the energy density of lithium batteries.

As shown in FIG. 1 , the first cover plate 510 is provided with a first package skirt 512, the first package skirt 512 is located around the notch of the first accommodation groove 511, the second cover plate 520 is provided with a second package skirt, the second package skirt is located around the notch of the second accommodation groove, the first package skirt 512 cooperates with the second package skirt, and the first negative tab 121 and the first positive tab 111 protrude from the interface between the first package skirt 512 and the second package skirt. In addition to opening mounting holes, the sealing performance of the battery is further improved.

In addition, hot-melt adhesive is provided between the interface of the first packaging skirt 512 and the second packaging skirt, and the packaging of the first cover plate 510 and the second cover plate 520 is realized by hot pressing.

It is worth noting that, continuing as shown in FIG. 1 , the first sealing portion is arranged on the two sides where the first positive tab 111 and the first negative tab 121 are in contact with the packaging membrane case 50, and the second sealing portion is arranged on the two sides where the second positive tab 211 and the second negative tab 221 are in contact with the packaging membrane case 50, and the length of the first sealing portion and the second sealing portion are greater than the width of the first packaging skirt 512 and the second packaging skirt, so as to improve the height of the first negative tab 121, the second positive tab 211 and the first packaging skirt. The reliability of the seal between the side 512 and the second package skirt.

In some other embodiments, the battery further includes a protective adhesive layer, which covers the connector 40, the first sealing part, the second sealing part, the first bending part, and the second bending part, so as to prevent the connector 40, the first sealing part, the second sealing part and other components from being damaged during transportation or use of the battery, resulting in connection failure.

As shown in Figure 1, the first positive tab 111, the first negative tab 121, the second positive tab 211, and the second negative tab 221 all protrude from the same side of the packaging membrane case 50. Since each tab is drawn out from the packaging membrane case 50, it is necessary to perform strict sealing treatment at the junction of the packaging membrane case 50 to prevent the electrolyte from leaking from the installation port. It is necessary to reserve an installation space in the packaging film case 50, thus increasing the length of the battery; and if tabs are provided on both sides of the battery, then twice the installation space needs to be reserved, so extending the first positive pole tab 111, the first negative pole tab 121, the second positive pole tab 211, and the second negative pole tab 221 from the same side of the packaging film case 50 can reduce the length of the battery.

In some realizable embodiments, as shown in FIG. 6b and FIG. 7b, there are multiple first negative tabs 121, and the multiple first negative tabs 121 are all connected to the connector 40; and/or, there are multiple second positive tabs 211, and the multiple second positive tabs 211 are all connected to the connector 40.

In some embodiments, as shown in FIG. 6a , one side of the first negative electrode sheet 120 is provided with a plurality of first negative tabs 121 at intervals. After crimping, the projections of the multiple first tabs along the thickness direction of the first winding core 10 overlap, and the multiple first negative tabs 121 are connected to one end of the connector 40. In this embodiment, the first winding core 10 and the connector 40 are connected at multiple points to enhance the reliability of the connection. At the same time, the arrangement of multiple first negative tabs 121 can disperse the current. 1 are in a parallel state, so that the total resistance of the multiple first negative tabs 121 becomes smaller, thereby reducing the heat generated on the first winding core 10 .

In some other embodiments, as shown in FIG. 7 b , one side of the second positive electrode sheet 210 is provided with a plurality of second positive tabs 211 at intervals. The projections of the plurality of second positive tabs 211 along the thickness direction of the second winding core 20 overlap, and the plurality of second positive tabs 211 are connected to the other end of the connector 40. In this embodiment, the second winding core 20 and the connector 40 are connected at multiple points to enhance the reliability of the connection; 1 are in a parallel state, so that the total resistance of the multiple second positive tabs 211 becomes smaller, thereby reducing the heat generated on the second winding core 20 .

Of course, in the embodiment of the present application, as shown in Fig. 8a and Fig. 8b, the cell of the battery can also be made by stacking the positive electrode sheet, the diaphragm layer, and the negative electrode sheet, that is, the first cell 10 is a stacked structure, and the second cell 20 is a stacked structure.

The number of battery cells is not limited to two, and may also include a third battery cell, a fourth battery cell, a fifth battery cell, etc., wherein the setting position and connection relationship between two adjacent battery cells are the same as the first battery cell 10 and the second battery cell 20 in the above implementation, and will not be repeated here.

In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with this embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without conflicting with each other.

Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limitations on the present application. Those skilled in the art can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

A battery, characterized by comprising: an encapsulating film case, and a first cell and a second cell located in the encapsulating film case;

An isolation layer is provided in the packaging film case, and the isolation layer divides the packaging film case into two independent first cavities and second cavities, the first cell is arranged in the first cavity, and the second cell is arranged in the second cavity;

The first electric core has a first positive tab and a first negative tab extending out of the packaging film;

The second electric core has a second positive tab and a second negative tab extending out of the packaging film;

The first negative tab is electrically connected to the second positive tab.
The battery according to claim 1, wherein the first cell and the second cell are arranged side by side.
The battery according to claim 1, wherein a first groove and a second groove are arranged on the isolation layer, the first battery cell is arranged in the first groove, and the second battery cell is arranged in the second groove.
The battery according to claim 3, wherein a groove wall of the first groove close to the second groove communicates with a groove wall of the second groove close to the first groove.
The battery according to claim 3, wherein the bottom of the first groove is located on the first side of the isolation layer, the bottom of the second groove is located on the second side of the isolation layer, and the first side is opposite to the second side.
The battery according to any one of claims 3-5, wherein the groove depth of the first groove is greater than or equal to half the thickness of the first battery cell;

And/or, the groove depth of the second groove is greater than or equal to half of the thickness of the second cell.
The battery according to any one of claims 3-5, characterized in that, the length of the isolation layer is less than or equal to the length of the packaging film;

And/or, the width of the isolation layer is less than or equal to the width of the packaging membrane.
The battery according to any one of claims 1-5, characterized in that the battery further comprises a connector, and the connector is connected to both the first negative tab and the second positive tab.
The battery according to any one of claims 1-5, wherein the encapsulating film case comprises a first cover plate and a second cover plate, a first accommodating groove is provided on one side of the first cover plate, the first battery cell and the second battery cell are both accommodated in the first accommodating groove, and the second cover plate covers the first cover plate and closes the first accommodating groove.
The battery according to any one of claims 1-5, wherein the encapsulating membrane case comprises a first cover plate and a second cover plate, a first accommodation groove is provided on one side of the first cover plate, a second accommodation groove is provided on one side of the second cover plate, the second cover plate covers the first cover plate, and the first accommodation groove and the second accommodation groove are surrounded by an accommodation groove for accommodating the first cell and the second cell.
The battery according to claim 8, wherein the packaging film case further comprises a first sealing portion sealing the first positive tab and the first negative tab and a second sealing portion sealing the second positive tab and the second negative tab;

The first negative tab includes a first bent portion bent onto the first sealing portion;

The second positive tab includes a second bent portion bent onto the second sealing portion;

The connecting piece connects the first bending part and the second bending part respectively.
The battery according to claim 11, wherein the battery further comprises a protective adhesive layer covering the connector, the first sealing portion, the second sealing portion, the first bending portion, and the second bending portion.
The battery according to any one of claims 1-5, characterized in that, the first battery cell is a wound structure or a laminated structure;

The second electric core is a winding structure or a laminated structure.