WO2022237517A1

WO2022237517A1 - Battery

Info

Publication number: WO2022237517A1
Application number: PCT/CN2022/088957
Authority: WO
Inventors: 卫志达; 王智峰; 彭宁; 谢斌; 徐延铭
Original assignee: 珠海冠宇电池股份有限公司
Priority date: 2021-05-13
Filing date: 2022-04-25
Publication date: 2022-11-17
Also published as: CN113285148B; CN113285148A

Abstract

The present application provides a battery. The battery provided by the present application comprises a housing and a coiled cell located in the housing; the coiled cell comprises multiple layers of coiled electrode plates; a first tab is connected in the coiled cell; the first tab comprises a connecting portion; and the connecting portion is connected to the inner wall of the housing, wherein the electrode plate located on the outermost layer of the coiled cell is provided with a relief notch, and the connecting portion is located in the relief notch. The battery provided by the present application has a reasonably configured internal structure, and the first tab does not occupy a thickness space of the battery, so that the energy density of the battery is improved.

Description

a battery

This application claims the priority of the Chinese patent application with the application number 202110520647.7 and the application title "a battery" submitted to the China Patent Office on May 13, 2021, the entire contents of which are incorporated in this application by reference.

technical field

The present application relates to the technical field of batteries, in particular to a battery.

Background technique

Electronic devices such as electronic watches, electronic scales, and smart wearable devices are usually equipped with batteries. For example, electronic devices are equipped with lithium-ion batteries, which provide electrical energy to electronic devices through battery discharge.

Taking the lithium-ion battery in an electronic watch as an example, the battery includes a shell and a cell inside the shell, the shell includes a negative shell and a positive flange, and the negative shell and the positive flange are insulated and connected; the battery is composed of a positive The pole piece, the negative pole piece and the diaphragm are wound together, and the diaphragm is sandwiched between the positive pole piece and the negative pole piece. Wherein, the positive tab on the positive pole piece is welded to the positive flange plate, and the negative pole tab on the negative pole piece is welded to the negative shell.

However, the internal structure of the existing battery is unreasonably arranged, the tabs occupy a large space, and the energy density of the battery is low.

Contents of the invention

In order to solve at least one of the problems mentioned in the background technology, the present application provides a battery. The internal structure of the battery is reasonably arranged, and the tabs do not occupy the thickness space of the battery, thereby improving the energy density of the battery.

In order to achieve the above object, the application provides the following technical solutions:

The present application provides a battery, which includes a casing and a winding core located in the casing. The winding core includes multi-layer pole pieces wound and arranged, and a first tab is connected to the winding core. The first tab includes a connecting portion, and the connecting portion It is connected with the inner wall of the casing; wherein, the pole piece located on the outermost layer of the winding core is provided with an avoidance gap, and the connecting part is located in the avoidance gap.

As for the above-mentioned battery, optionally, the first tab is folded from the end connected to the winding core to the outermost layer of the winding core to form a connecting part, and the connecting part is attached to the inner wall of the casing.

For the battery as described above, optionally, the casing includes a metal outer frame, an insulating plastic frame and a metal plate, and the metal outer frame and the metal plate are fastened and connected by the insulating plastic frame; wherein, the winding core is closely attached to the metal plate. One tab is connected with the inner wall of the metal plate.

For the battery described above, optionally, the metal plate includes an electrode metal layer and a reinforcing metal layer, the first tab is connected to the electrode metal layer, and the reinforcing metal layer is located on a side of the electrode metal layer away from the winding core.

As for the aforementioned battery, optionally, the ratio of the thickness of the electrode metal layer to the thickness of the reinforcing metal layer is greater than 2:1.

For the battery described above, optionally, the metal outer frame includes a flange, the insulating plastic frame is attached to the flange, and the insulating rubber frame coincides with the flange.

As for the battery described above, optionally, a second tab is connected to the winding core, and the second tab is connected to the inner sidewall of the metal frame.

As for the battery described above, optionally, the outer wall of the metal frame is provided with a reinforcing plate, and the reinforcing plate corresponds to the second tab.

As for the battery described above, optionally, a pressure relief groove is provided on the inner wall of the metal frame opposite to the metal plate.

As for the above-mentioned battery, optionally, a liquid injection hole is opened on the side wall of the metal frame, and a sealing member is provided on the upper cover of the liquid injection hole.

The battery provided by this application includes a casing and a winding core provided inside the casing. The winding core is formed by winding pole pieces, and a first tab is connected to the winding core. The connecting part of the first tab is connected to the inner wall of the casing. Connection; by setting the avoidance gap on the pole piece of the outermost layer of the winding core, the connection part of the first tab is located in the avoidance gap, so that the first tab does not occupy additional thickness space in the shell, and the outermost layer of the winding core The pole piece can be closely attached to the inner wall of the casing, thereby rationalizing the internal structure of the battery and increasing 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 the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are Some examples of this application. For those skilled in the art, other drawings can also be obtained based on these drawings without creative effort.

Fig. 1 is an exploded view of a viewing angle of the battery provided by the embodiment of the present application;

Fig. 2 is a cross-sectional view of the corresponding first tab part of the battery provided in the embodiment of the present application;

Figure 3 is a partially enlarged view of Figure 2;

Fig. 4 is a cross-sectional view of the corresponding second tab part of the battery provided in the embodiment of the present application;

Fig. 5 is an exploded view of another perspective of the battery provided by the embodiment of the present application;

Fig. 6 is a top view of the metal frame provided by the embodiment of the present application;

Fig. 7 is a partial enlarged view of the pressure relief groove in the metal frame provided by the embodiment of the present application;

Fig. 8 is a side view of the battery provided by the embodiment of the present application;

FIG. 9 is a partial structural diagram of a metal outer frame provided by an embodiment of the present application.

Explanation of reference signs:

100 - battery;

1-shell; 2-rolling core;

11-metal frame; 12-metal plate; 13-insulating plastic frame; 21-pole piece; 22-first tab; 23-second tab;

111-frame body; 112-flange; 113-reinforcing plate; 114-pressure relief groove; 115-liquid injection hole; 116-seal; 121-electrode metal layer; 122-strengthening metal layer; - connection part.

Detailed ways

Batteries in electronic devices such as electronic watches, electronic scales, and smart wearable devices, such as polymer lithium-ion batteries, are packaged with aluminum-plastic films, or batteries are packaged in steel shells.

In the prior art, whether it is a battery packaged in aluminum-plastic film or a battery packaged in a steel case, since the positive tab in the core in the battery needs to be connected to the casing of the battery, the positive tab is usually folded to the outer surface of the core , and welded on the inner wall of the case, the positive tab needs to occupy a certain thickness of the battery space, therefore, the outer surface of the winding core cannot fit tightly with the battery case, which will lose the energy density of the battery.

In addition, due to the low strength of the aluminum-plastic film, it is prone to damage and leakage, which poses a safety hazard; while the steel case needs to be stamped and formed, which increases the difficulty of manufacturing the battery case.

In order to solve the above-mentioned technical problems, the embodiments of the present application provide a battery. The tabs inside the battery do not occupy additional thickness space, which can increase the energy density of the battery. The battery has high strength, good safety and is easy to manufacture.

In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments It is a part of the embodiments of this 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.

Fig. 1 is an exploded view of a viewing angle of the battery provided by the embodiment of the present application; Fig. 2 is a cross-sectional view of the corresponding first tab of the battery provided by the embodiment of the present application; Fig. 3 is a partially enlarged view of Fig. 2 .

Referring to FIG. 1, the battery 100 provided by this embodiment includes a casing 1 and a winding core 2, the winding core 2 is located in the casing 1, and the winding core 2 is used as a current collector in the battery 100. When the battery 100 is charged, the winding core 2 2 Collecting current, when the battery 100 is discharged, the current in the winding core 2 flows out through the casing 1 to charge the electronic device.

In a specific application, the battery 100 may be a cubic battery 100. For example, the casing 1 of the battery 100 is roughly in the shape of a cuboid, and the winding core 2 in the casing 1 is wound to form a winding core 2 similar to a cuboid. The thickness direction of the housing 1 forms a multi-layered structure.

Specifically, the winding core 2 includes a pole piece 21 and a separator (not shown in the figure), and the pole piece 21 and the separator are wound together to form the winding core 2 . Wherein, the pole piece 21 may include a positive pole piece (not shown in the figure) and a negative pole piece (not shown in the figure), and the separator is sandwiched between the positive pole piece and the negative pole piece to insulate and isolate the positive pole piece and the negative pole piece. The negative pole piece, the positive pole piece, the separator and the negative pole piece are stacked and wound from inside to outside to form the winding core 2 .

The winding core 2 is connected to the casing 1 through the tabs, and the current in the winding core 2 is transmitted to the casing 1 through the tabs, and discharged from the casing 1 outward. Wherein, the tab includes a positive tab and a negative tab, the positive tab is connected to the positive pole piece, and the negative pole tab is connected to the negative pole piece; the housing 1 includes a positive pole part and a negative pole part, the positive pole tab is connected to the positive pole part of the housing 1, and the negative pole tab is connected to the negative pole piece. Connect to the negative part of case 1.

Referring to FIG. 1 , in this embodiment, the winding core 2 is connected with a first tab 22. Exemplarily, the first tab 22 may be a positive tab, and the first tab 22 is connected to the multi-layer wound pole. On the positive electrode sheet 21 in the sheet 21 , for example, one end of the first tab 22 is connected to the positive electrode sheet 21 in the middle of the winding core 2 , and the other end of the first tab 22 is connected to the positive part of the housing 1 .

In one embodiment, one end of the first tab 22 is connected to the pole piece 21, the other end of the first tab 22 protrudes from the end surface of the winding core 2 to the outside of the winding core 2, and the first tab 22 The other end is folded to the outer surface of the core 2 to connect with the inner wall of the housing 1 . Wherein, the part of the first tab 22 that is turned over to the outer surface of the winding core 2 is its connecting portion 221 , and the first tab 22 is connected to the inner wall of the casing 1 through the connecting portion 221 .

In this embodiment, an avoidance notch 211 is provided on the outermost pole piece 21 of the winding core 2 , and the avoidance notch 211 is located on one side of the connecting portion 221 of the winding core 2 connected to the first tab 22 . By opening an avoidance gap 211 on the outermost pole piece 21 of the winding core 2 , the connecting portion 221 of the first tab 22 can be located in the avoidance gap 211 .

By making the connecting portion 221 of the first tab 22 located in the avoidance gap 211 on the outermost pole piece 21 of the winding core 2, the connecting portion 221 of the first tab 22 does not occupy the thickness space of the battery 100, and the winding core 2 The surface in the thickness direction of the casing 1 can be closely attached to the inner wall of the casing 1 , for example, the surfaces on both sides of the core 2 are closely attached to the inner walls of the casing 1 respectively.

In this way, it is avoided that the connecting portion 221 of the first tab 22 alone occupies the thickness space of the casing 1, thereby avoiding the gap between the outer surface of the winding core 2 and the inner wall of the casing 1, and avoiding the resulting damage to the battery 100. Loss of energy density; by making the outer surface of the winding core 2 closely adhere to the inner wall of the casing 1, there is no gap between the winding core 2 and the casing 1 in the thickness direction of the casing 1, so that the battery 100 can be lifted energy density.

As mentioned above, one end of the first tab 22 is connected to the positive plate 21 in the winding core 2, and the other end of the first tab 22 extends out of the winding core 2 and is folded toward the outermost layer of the winding core 2, The other end of the first tab 22 forms a connection portion 221, which corresponds to the outermost layer of the winding core 2 in the thickness direction; wherein, the pole piece 21 of the outermost layer of the winding core 2 is provided with an escape gap 211 , the connecting portion 221 of the first tab 22 is located in the avoidance gap 211 .

In addition, as shown in FIG. 2 and FIG. 3 , the connection portion 221 of the first tab 22 can be attached to the inner wall of the housing 1, which facilitates the connection between the first tab 22 and the inner wall of the housing 1, and can improve the first tab 22. The connection strength between the connecting portion 221 of a tab 22 and the inner wall of the casing 1 . Exemplarily, the connecting portion 221 of the first tab 22 and the inner wall of the housing 1 may be connected by welding.

Taking the thickness of the connection portion 221 of the first tab 22 as an example smaller than the thickness of the pole piece 21, one side surface of the connection portion 221 of the first tab 22 is attached to the inner wall of the housing 1, and the connection of the first tab 22 There is a gap between the other side surface of the portion 221 and the pole piece 21 exposed in the avoidance gap 211; or, when the thickness of the connecting portion 221 of the first tab 22 is relatively thick, the connection of the first tab 22 The two side surfaces of the portion 221 can be attached to the inner wall of the casing 1 and the surface of the pole piece 21 respectively.

Referring to FIG. 1 , in this embodiment, the case 1 of the battery 100 includes a metal outer frame 11 , a metal plate 12 and an insulating plastic frame 13 . Specifically, the metal frame 11 and the metal plate 12 are fastened and connected to each other to form the main support structure of the housing 1, and the insulating plastic frame 13 is connected between the metal frame 11 and the metal plate 12. On the one hand, the insulating plastic frame 13 can The bonding between the metal frame 11 and the metal plate 12 is realized. On the other hand, the insulating plastic frame 13 can insulate and isolate the metal frame 11 and the metal plate 12 to ensure the normal operation of the battery 100 .

In a specific embodiment, the metal frame 11 can be used as the negative electrode casing 1 of the battery 100, and the metal plate 12 can be used as the positive plate body of the battery 100, that is, the metal frame 11 can be used as the external negative electrode of the battery 100, and the metal plate 12 can be used as the positive electrode plate body of the battery 100. as the external positive electrode of the battery 100 .

Taking the first tab 22 as a positive tab as an example, the connection portion 221 of the first tab 22 is connected to the metal plate 12 as the external positive electrode of the battery 100, that is, the connection portion 221 of the first tab 22 is attached to the metal plate 12 On the inner wall of the metal plate 12 , for example, the connection portion 221 of the first tab 22 is welded to the inner wall of the metal plate 12 .

FIG. 4 is a cross-sectional view of a part corresponding to the second tab of the battery provided in the embodiment of the present application. 1 and 4, the winding core 2 is also connected with a second tab 23, for example, the second tab 23 is a negative tab, and the second tab 23 is connected to the negative electrode sheet 21 in the winding core 2 , and the second tab 23 is connected to the metal frame 11 as the external negative electrode in the case 1 of the battery 100 .

For example, one end of the second tab 23 is connected to the negative electrode sheet 21 in the middle of the winding core 2, and the other end of the second tab 23 protrudes out of the end face of the winding core 2 and is connected to one side of the metal frame 11. The other end of the second tab 23 is connected to the inner side wall of this side of the metal frame 11 . Exemplarily, the other end of the second tab 23 may be welded on the inner sidewall of the metal frame 11 .

By setting the escape gap 211 on the outermost pole piece 21 of the winding core 2, the connecting portion 221 of the first tab 22 is located in the avoidance gap 211, so that the outermost pole piece 21 of the winding core 2 and the metal plate 12 closely fit to increase the energy density of the battery 100 . In addition, as shown in FIG. 2 and FIG. 4 , the outer surface of the other side of the winding core 2 can be closely attached to the inner surface of the metal frame 11. In this way, the internal space of the casing 1 is fully utilized, and the battery 100 is effectively improved. energy density.

In order to improve the strength of the metal plate 12, as shown in FIG. Outside, the electrode metal layer 121 is located inside the reinforcement metal layer 122 .

The connection part 221 of the first tab 22 is connected to the electrode metal layer 121, the electrode metal layer 121 is used as the external positive electrode of the battery 100, and the reinforcing metal layer 122 is used to improve the strength of the metal plate 12, so as to avoid the phenomenon of damage and leakage of the battery 100 , improving the use safety of the battery 100 .

Taking the first tab 22 welded to the electrode metal layer 121 as an example, the weld between the first tab 22 and the electrode metal layer 121 should not exceed the thickness of the electrode metal layer 121, that is, the first tab 22 is connected to the electrode metal layer 121. Within the thickness range of the electrode metal layer 121 , the part of the first tab 22 is prevented from penetrating through the electrode metal layer 121 and connected to the reinforcing metal layer 122 , so as to prevent the electrical connection failure between the first tab 22 and the metal plate 12 .

By setting the stacked electrode metal layer 121 and the reinforcing metal layer 122, the electrode metal layer 121 serves as the external positive electrode of the battery 100 to ensure the normal operation of the battery 100, and the reinforcing metal layer 122 can increase the strength of the metal plate 12, thereby increasing the strength of the battery 100, Avoid potential safety hazards in the battery 100 and ensure the safety performance of the battery 100 .

In addition, the metal plate 12 may be formed by a stamping forming process. For example, the electrode metal layer 121 and the reinforcement metal layer 122 are stamped and formed respectively, and the electrode metal layer 121 and the reinforcement metal layer 122 are connected by welding, bonding, or screws, bolts and other connectors.

Exemplarily, the electrode metal layer 121 can be an aluminum layer, or the electrode metal layer 121 can be other metal layers that can serve as the positive electrode of the battery 100; the reinforcing metal layer 122 can be a stainless steel layer or a nickel layer, or the reinforcing metal layer 122 can also be It may be other metal layers that can increase the strength of the metal plate 12 without affecting the performance of the electrode metal layer 121 .

In a specific implementation manner, the ratio of the thickness of the electrode metal layer 121 to the thickness of the reinforcing metal layer 122 may be greater than 2:1. In this way, the thicker electrode metal layer 121 can ensure the working performance of the battery 100, and the thinner reinforcing metal layer 122 is set to cover the electrode metal layer 121, which can increase the strength of the metal plate 12 and form a positive electrode for the electrode metal layer 121. Protect. In addition, the thinner reinforcing metal layer 122 has little effect on the overall thickness of the metal plate 12 , which can reduce the thickness and weight of the battery 100 .

FIG. 5 is an exploded view from another perspective of the battery provided by the embodiment of the present application. Referring to FIG. 5 , in this embodiment, the metal outer frame 11 includes a frame body 111 and a flange 112 . The frame body 111 is the main structure of the metal outer frame 11, one side of the frame body 111 is open, the metal plate 12 is covered on the open side of the frame body 111, and the winding core 2 is located in the space surrounded by the frame body 111 and the metal plate 12 ; Flanging 112 surrounds the outer edge of the open side of the frame body 111 , and the metal frame 11 is connected to the metal plate 12 through the flanging 112 .

Specifically, one side surface of the insulating plastic frame 13 is attached to the flange 112 of the metal outer frame 11 , and the metal plate 12 is attached to the other side surface of the insulating plastic frame 13 . Since the flange 112 of the metal frame 11 is connected to the metal plate 12, in order to ensure the insulation performance between the metal frame 11 and the metal plate 12, the insulating plastic frame 13 should be able to completely cover the flange 112 of the metal frame 11 to avoid exposure. out of the local area of the flange 112 of the metal frame 11, so as to avoid contact between the flange 112 of the metal frame 11 and the metal plate 12, or because the gap between the flange 112 of the metal frame 11 and the metal plate 12 is small And turn on.

In addition, the larger the area of the flange 112 of the metal frame 11 covered by the insulating plastic frame 13 is, the stronger the connection between the metal frame 11 and the metal plate 12 connected by the insulating plastic frame 13 is.

Referring to Fig. 3, in a specific implementation manner, the insulating plastic frame 13 can overlap with the flange 112, that is, the shape and size of the insulating plastic frame 13 and the flange 112 are consistent, so that both the metal outer frame 11 and the flange 112 can be guaranteed. The insulation performance between the metal plates 12 ensures that the metal outer frame 11 and the metal plate 12 are firmly connected; and avoids the part of the insulating plastic frame 13 from being exposed outside the casing 1 of the battery 100, so as not to affect the performance of the battery 100 and affect the performance of the battery 100. Tolerance of the insulating plastic frame 13 without affecting the appearance of the battery 100 .

Exemplarily, the metal outer frame 11 can be formed by stamping, and the wall thickness of the metal outer frame 11 can be 0.03-0.1 mm. For example, the wall thickness of the metal outer frame 11 may be 0.04 mm, 0.06 mm, 0.08 mm or 0.1 mm, which is not specifically limited in this embodiment.

In addition, the width of the flange 112 of the metal frame 11 may be 1.0-5.0 mm, for example, the width of the flange 112 of the metal frame 11 is 1.0 mm, 2.0 mm, 3.0 mm, 4.0 mm or 5.0 mm. The width of the insulating plastic frame 13 is consistent with the width of the metal outer frame 11, and the thickness of the insulating plastic frame 13 can be 0.03-0.1mm, for example, the thickness of the insulating plastic frame 13 is 0.04mm, 0.06mm, 0.08mm or 0.1mm.

FIG. 6 is a top view of the metal frame provided by the embodiment of the present application; FIG. 7 is a partially enlarged view of the pressure relief groove in the metal frame provided by the embodiment of the present application. 6 and 7, the metal frame 11 can also be provided with a pressure relief groove 114, and the pressure relief groove 114 is used to release the pressure when the internal pressure of the battery 100 is too high, so as to prevent the explosion accident of the battery 100 and ensure the safety of the battery. 100% security.

For example, the pressure relief groove 114 can be arranged on the inner wall of the side of the metal frame 11 opposite to the metal plate 12. As shown in FIG. The wall thickness of the metal frame 11 at the slot 114 is smaller than the wall thickness of other parts of the metal frame 11 . When the internal pressure of the battery 100 is too high, the pressure acts on the pressure relief groove 114. Since the wall thickness of the metal outer frame 11 at the pressure relief groove 114 is relatively small, the metal outer frame 11 is prone to cracks at the pressure relief groove 114, thereby causing cracks. to timely release pressure.

Taking the wall thickness of the metal frame 11 as 0.1 mm as an example, the wall thickness of the metal frame 11 at the pressure relief groove 114 may be 0.01-0.05 mm.

Fig. 8 is a side view of the battery provided in the embodiment of the present application; Fig. 9 is a partial structural view of the metal outer frame provided in the embodiment of the present application. 8 and 9, the outer wall of the metal frame 11 can also be provided with a reinforcement plate 113, and the reinforcement plate 113 can be correspondingly arranged on the part of the metal frame 11 connected to the second tab 23, that is, the reinforcement plate 113 It is located on opposite sides of the same part of the metal outer frame 11 as the second tab 23 .

In practical applications, the battery 100 is connected to the external circuit through the part of the metal frame 11 connected to the second tab 23, that is, the part of the metal frame 11 corresponding to the second tab 23 is the contact point of the external negative pole of the battery 100, When the battery 100 is connected to the outside, the contact point is connected to the external circuit, for example, the contact point is in contact with the negative pole point in the electronic device.

During the long-term use of the battery 100, it is inevitable that the battery 100 will be repeatedly plugged and pulled out in the electronic device, and the contact point corresponding to the second tab 23 on the metal frame 11 of the battery 100 will rub repeatedly, which will damage the metal frame. The outer wall of the metal frame 11 causes wear and tear. By setting the reinforcing plate 113 on the outer wall of the metal frame 11 corresponding to the second tab 23, the reinforcing plate 113 increases the wall thickness of the metal frame 11 here, which can prevent the battery from 100 destroys the side wall of the metal outer frame 11 during repeated connection with the electronic device.

Referring to FIG. 8 and FIG. 9 , a liquid injection hole 115 is opened on the side wall of the metal outer frame 11 , and the electrolyte solution of the battery 100 is injected into the casing 1 through the liquid injection hole 115 . Both the liquid injection hole 115 and the reinforcement plate 113 can be located on the same side of the metal frame 11 , or the liquid injection hole 115 and the reinforcement plate 113 are respectively arranged on different sides of the metal frame 11 . The diameter of the liquid injection hole 115 may be 0.5-2.0mm. Exemplarily, the diameter of the liquid injection hole 115 may be 0.5mm, 0.75mm, 1.0mm, 1.25mm, 1.5mm, 1.75mm or 2.0mm.

In addition, the liquid injection hole 115 is covered with a seal 116 , and the liquid injection hole 115 is blocked by the seal 116 to seal the electrolyte in the casing 1 of the battery 100 . Part of the sealing member 116 is blocked in the liquid injection hole 115, and the outer edge of the sealing member 116 is fixed on the outer metal frame 11 of the liquid injection hole 115. For example, the sealing member 116 is welded on the metal outer frame 11 to This achieves sealing of the liquid injection hole 115 .

This embodiment also provides a manufacturing process of the battery 100, which is used to assemble and form the battery 100 as described above. Specifically, firstly, the metal frame 11 of the battery 100 is stamped and formed, and the inner wall of the metal frame 11 opposite to the metal plate 12 is provided with a pressure relief groove 114, and the side wall of the metal frame 11 is provided with a liquid injection hole 115, and the metal The outer frame 11 has a flange 112, and then, the reinforcing plate 113 is welded on the metal outer frame 11 corresponding to the position of the second tab 23; the metal plate 12 is stamped and formed, and the metal plate 12 includes a stacked electrode metal layer 121 and a reinforcement metal layer 122 .

Wherein, it can be understood that the metal frame 11 can be formed first and then the metal plate 12 can be formed, or the metal plate 12 can be formed first and then the metal frame 11 can be formed, which is not limited in this embodiment.

After winding to form the winding core 2, the first pole tab 22 is connected on one pole piece 21 (positive pole piece) in the winding core 2, and the second pole piece 23 is connected on the other pole piece 21 (negative pole piece). At the same time, an escape gap 211 is provided on the outermost pole piece 21 of the winding core 2 . First, the second tab 23 is welded on the inner side wall of the metal frame 11, the winding core 2 is put into the metal frame 11 as a whole, and then the first tab 22 is welded to the metal plate 12, and then the metal plate 12 The insulating plastic frame 13 is bonded to the metal outer frame 11 .

After the bonding of the metal frame 11 and the metal plate 12 is completed, put the casing 1 into a baking oven to bake, and discharge the water vapor inside the winding core 2 through the liquid injection hole 115; after the water vapor is discharged, pass through the liquid injection hole 115 Electrolyte is injected into the casing 1 , and finally the sealing member 116 is laser welded on the outer metal frame 11 of the liquid injection hole 115 , and the sealing member 116 blocks the liquid injection hole 115 .

The battery 100 and its preparation process provided in this embodiment, the battery 100 includes a casing 1 and a winding core 2 provided inside the casing 1, the winding core 2 is formed by winding a pole piece 21, and the winding core 2 is connected with a first pole Ear 22, the connection portion 221 of the first tab 22 is connected to the inner wall of the housing 1; by setting the avoidance gap 211 on the pole piece 21 of the outermost layer of the winding core 2, the connection portion 221 of the first tab 22 is located at the avoidance position. In this way, the first tab 22 does not occupy additional thickness space in the casing 1, and the pole piece 21 on the outermost layer of the winding core 2 can be closely attached to the inner wall of the casing 1, thereby rationalizing the interior of the battery 100 structure to increase the energy density of the battery 100 .

In the description of this embodiment, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", The orientation or positional relationship indicated by "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner" and "outer" are based on those shown in the drawings Orientation or positional relationship is only for the convenience of describing this embodiment and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, so it cannot be understood as a limitation to this embodiment. limit.

In the description of this embodiment, it should be understood that the terms "comprising" and "having" and any variations thereof are intended to cover a non-exclusive inclusion, for example, a process comprising a series of steps or units A method, system, product or device is not necessarily limited to those steps or elements explicitly listed, but may include other steps or elements not explicitly listed or inherent to the process, method, product or device.

Unless otherwise clearly specified and limited, the terms "installation", "connection", "connection", "fixation" and so on should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral body; it can be It can be directly connected or indirectly connected through an intermediary, and can be an internal connection between two elements or an interaction relationship between two elements. Those of ordinary skill in the art can understand the specific meanings of the above terms in this embodiment according to specific situations.

It can be understood that the words indicating orientation, such as upper, lower, upper, lower, upper, lower, top, bottom, top, bottom, top surface, and bottom surface, mentioned in this embodiment are based on the installation and use status of the device or equipment positional relationship. In addition, the terms "first", "second", etc. are used for descriptive purposes only, and should not be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit it; although the application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present application. scope.

Claims

A battery, characterized in that it includes a casing and a winding core located in the casing, the winding core includes multi-layer pole pieces wound and arranged, the winding core is connected with a first tab, and the first A tab includes a connecting portion connected to the inner wall of the housing; wherein, an avoidance notch is provided on the pole piece located on the outermost layer of the winding core, and the connecting portion is located in the avoidance notch .
The battery according to claim 1, wherein the first tab is folded from the end connected to the winding core to the outermost layer of the winding core to form the connecting portion, and the connecting portion is attached to the outermost layer of the winding core. fit on the inner wall of the housing.
The battery according to claim 1, wherein the casing comprises a metal outer frame, an insulating plastic frame, and a metal plate, and the metal outer frame and the metal plate are fastened and connected by the insulating plastic frame; wherein , the winding core is closely attached to the metal plate, and the first tab is connected to the inner wall of the metal plate.
The battery according to claim 3, wherein the metal plate includes an electrode metal layer and a reinforcing metal layer, the first tab is connected to the electrode metal layer, and the reinforcing metal layer is located on the electrode metal layer. The side of the layer facing away from the core.
The battery according to claim 4, wherein the ratio of the thickness of the electrode metal layer to the thickness of the reinforcing metal layer is greater than 2:1.
The battery according to claim 3, wherein the metal outer frame includes a flange, the insulating plastic frame is attached to the flange, and the insulating plastic frame overlaps with the flange.
The battery according to any one of claims 3-6, wherein a second tab is further connected to the winding core, and the second tab is connected to the inner side wall of the metal outer frame.
The battery according to claim 7, wherein a reinforcement plate is provided on the outer wall of the metal frame, and the reinforcement plate corresponds to the second tab.
The battery according to any one of claims 3-6, wherein a pressure relief groove is provided on the inner wall of the metal outer frame opposite to the metal plate.
The battery according to any one of claims 3-6, wherein a liquid injection hole is opened on the side wall of the metal outer frame, and a sealing member is provided on the upper cover of the liquid injection hole.