CN220138633U - Cylindrical battery and electric equipment - Google Patents

Abstract

The utility model belongs to the technical field of batteries, and discloses a cylindrical battery and electric equipment. The cylindrical battery comprises a battery core, wherein two opposite ends of the battery core extend out of polar lugs, the polar lugs at the two ends are opposite in polarity, and a first inclined plane is formed at one end, far away from the battery core, of the polar lug at least one end; the shell is provided with an opening and a bottom wall opposite to the opening, the bottom wall is provided with a first surface and a second surface which is opposite to the first surface, a first boss protruding out of the second surface is formed on the bottom wall, and a second inclined plane is formed on the first boss; the battery cell is accommodated in the shell, the first inclined plane is attached to the second inclined plane, and the electrode lug is fixedly welded with the bottom wall. Through set up the first boss that has the second inclined plane on the diapire of casing for the diapire of casing can laminate the utmost point ear and rub the outward appearance after the flat.

Description

Cylindrical battery and electric equipment

Technical Field

The utility model relates to the technical field of batteries, in particular to a cylindrical battery and electric equipment.

Background

Currently, cylindrical batteries are widely applied to the market, and in order to solve the problem of high-current charge and discharge of batteries in the industry, a general battery core adopts a full-tab structure. The positive and negative lugs are respectively welded with the positive/negative current collecting plates, the positive/negative current collecting plates are provided with bending parts, the bending parts are required to be bent after welding and then packaged, the longer bending parts lead to the rising of the resistance value of the battery, and the rising of the temperature is also higher during high-current charge and discharge, so that the safety risk is brought. Thus, in the prior art, cylindrical cells have emerged that eliminate the folds or even directly the collector plate.

In general, the position of the liquid injection hole of the cylindrical battery corresponds to the position of the center hole, and liquid injection is performed through the center hole. In order to avoid blocking the position of the central hole, the height of the tab of the cell close to the position of the central hole is generally lower, or no tab exists, in other words, the tab on the inner side and the outer side of the cell has a height difference and a layer number difference. In addition, the lugs are generally flattened by rubbing, i.e., by arranging and flattening the lugs in a regular or a regular manner. As the lugs on the inner side and the outer side of the battery cell have the height difference and the layer number difference, the lug after being kneaded is an inclined plane rather than a plane perpendicular to the central axis of the battery cell.

The existing cylindrical battery is not provided with a current collecting disc bending part or a current collecting disc, but the bottom wall of the shell cannot adapt to the appearance of the flat-rolled tab, so that the problem of poor overcurrent capacity of the battery is brought.

Disclosure of Invention

The utility model aims to provide a cylindrical battery and electric equipment, and solves the problems that the overcurrent capacity of the battery is affected, the battery resistance is high and the overcurrent temperature is increased due to the fact that the lug of the conventional cylindrical battery is not attached to the bottom wall of a shell.

To achieve the purpose, the utility model adopts the following technical scheme:

in a first aspect, the utility model provides a cylindrical battery, which comprises a battery cell, wherein tab layers extend out of two opposite ends of the battery cell, the polarities of the tab layers at the two ends are opposite, and a first inclined plane is formed at one end, far away from the battery cell, of the tab layer at least one end; the shell is provided with an opening and a bottom wall opposite to the opening, the bottom wall is provided with a first surface and a second surface which is opposite to the first surface, a first boss protruding out of the second surface is formed on the bottom wall, and a second inclined plane is formed on the first boss; the battery cell is accommodated in the shell, the first inclined plane is attached to the second inclined plane, and the tab layer is welded and fixed with the bottom wall.

The lug layer forms a first inclined plane after being kneaded and flattened, and a second inclined plane formed by the first boss can be attached to the first inclined plane, so that the bottom wall of the shell can be attached to the appearance of the lug layer after being kneaded and flattened.

In some embodiments, the tab layer comprises a multi-layer tab formed with: the connecting part extends out of one end face of the battery cell from the pole piece in the battery cell; one end of the bending part is connected to the connecting part, and the other end of the bending part extends along the height direction of the battery cell and then bends towards the end surface position; the bending directions of all the tabs are consistent, so that the bending parts of all the tabs form a flat surface together, and the flat surface is the first inclined surface.

In some embodiments, the end face has at least one tab area and at least one non-tab area, the tab area and the non-tab area are adjacently arranged, the tab area is a sector area, and the tab layer of each tab area is formed with the first inclined plane; the number of the first bosses is at least one, and each first boss forms the second inclined plane; each tab area corresponds to one first boss.

In some embodiments, the cell has a central hole therethrough along a height direction of the cell; and a liquid injection hole is formed in the bottom wall corresponding to the position of the central hole, and the liquid injection hole is communicated with the central hole.

The liquid injection hole is arranged on the bottom wall of the battery shell, liquid is injected into the cylindrical battery through the liquid injection hole, and electrolyte flows through the center hole and is immersed into the battery core.

In some embodiments, a second boss is formed on the bottom wall on a side thereof having a second surface, and the liquid injection hole extends from the bottom wall and penetrates the second boss.

Since the thickness of the bottom wall is relatively thin, a second boss is provided to add strength to the liquid filling structure.

In some embodiments, the second boss protrudes into the central bore.

When the battery cell is provided with the electrode lug in the area close to the central hole, the electrode lug and the electrolyte flow channel can be separated by extending the second boss into the central hole, so that the electrolyte can be prevented from impacting the electrode lug close to the central hole during liquid injection, and the electrode lug is prevented from being impacted and torn.

In some embodiments, the battery cell has a central axis, and the height of the first boss gradually decreases from the central axis toward a direction away from the central axis.

In some embodiments, a groove is provided between the first boss and the second boss.

Electrolyte can be stored by providing grooves.

In some embodiments, the bottom wall is formed with a plurality of ribs on a side of the bottom wall having the first surface.

The strength of diapire can be strengthened in the setting of strengthening rib, guarantees utmost point ear layer and diapire welding effect.

In some embodiments, one end of the battery cell extends out of the positive electrode tab, the opposite end extends out of the negative electrode tab, the first inclined surface is formed on the positive electrode tab, and the positive electrode tab and the bottom wall are welded and fixed.

The positive tab is typically made of aluminum foil and the negative tab is typically made of copper foil, and because aluminum has a much lower melting point than copper, it is easier to weld the aluminum tab to the bottom wall of the case from the welding process, especially when the battery case is an aluminum case.

In a second aspect, the utility model further provides electric equipment, which comprises the battery.

The beneficial effects are that:

according to the utility model, the first boss is arranged on the bottom wall of the shell, and one end of the first boss, which is far away from the bottom wall of the shell, is arranged as an inclined plane to be attached to the appearance of the flat-rolled tab, so that the attaching effect of the bottom of the shell and the tab can be better improved, a larger overcurrent area can be ensured, and the resistance and overcurrent temperature rise of the battery are improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present utility model and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic cross-sectional view of a cylindrical battery according to the present utility model;

FIG. 2 is a schematic cross-sectional view of the positive electrode of the cylindrical battery of the present utility model;

FIG. 3 is a schematic view of the structure of the bottom wall of the cylindrical battery case of the present utility model;

FIG. 4 is a schematic cross-sectional view of the battery cell of the cylindrical battery of the present utility model;

FIG. 5 is a simplified schematic view of the positive tab of the cylindrical battery of the present utility model;

FIG. 6 is a schematic view of the structure of tab and non-tab regions of a cylindrical battery of the present utility model;

wherein reference numerals are as follows:

100a, 100b cylindrical cells;

10a, 10b cells; 11. an end face; 12. a tab region; 121. a positive electrode tab; 1211. a first inclined surface; 122. a negative electrode ear; 13. a non-tab region; 14. a tab; 141. a connection part; 142 bending parts; 15. a central bore; 151. a central shaft;

20. a housing; 21. a bottom wall 15; 211. a first surface; 212. a second surface; 22. a first boss; 221. a second inclined surface; 23. a liquid injection hole; 24. a second boss; 25. a groove; 26. reinforcing ribs;

30. a negative current collecting plate;

40. capping; 41. and a negative electrode column.

Detailed Description

Certain terms are used throughout the description and claims to refer to particular components. It will be appreciated by those of ordinary skill in the art that different terms may be used to refer to the same component. The description and claims do not take the form of an element differentiated by name, but rather by functionality. As used throughout the specification and claims, the word "comprise" is an open-ended term, and thus should be interpreted to mean "include, but not limited to. By "substantially" is meant that within an acceptable error range, a person skilled in the art can solve the technical problem within a certain error range, substantially achieving the technical effect. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In practice, the inventors of the present utility model found that the existing cylindrical battery, although eliminating the collector plate bent portion or collector plate, the bottom wall of the case thereof cannot accommodate the appearance of the tab after being flattened, thus resulting in poor overcurrent capability of the battery. For example, patent 202222553796.6 discloses a cylindrical battery, in which a mode of two ends out of a tab is adopted, the tab at one end is directly welded and fixed at the bottom of a housing, and the tab at the other end is electrically connected with a pole through a collecting disc without a bending part, wherein the bottom of the housing of the cylindrical battery is a plane. The lug after being kneaded is an inclined plane, so that the lug and the bottom of the shell cannot be effectively attached, and the patent cancels the current collecting disc, but brings about the problem of poor overcurrent capacity of the battery.

Specifically, in this cylindrical battery, since the bottom of the case is flat, the tab region having a low protruding height cannot be attached to the bottom of the case, and if the tab region having a high protruding height is forcibly attached, the tab region is wrinkled or torn. If the lug layer can not be effectively attached to the bottom wall, the welding effect can be affected, and the effective welding area is reduced, so that the overcurrent area is reduced, and the overcurrent capacity of the battery is reduced. In addition, the fixed effect of tab layer and diapire can be influenced in effective welding area reduction, and in the battery loading use, the tab atress is torn easily and breaks away from the diapire even, influences battery safety.

According to the cylindrical battery disclosed by the utility model, the first boss is arranged on the bottom wall of the shell, the second inclined plane formed by the first boss can adapt to the appearance of the pole lug layer after being flattened, and all pole lug areas can be bonded with the bottom wall, so that the problems can be avoided.

The cylindrical battery of the present utility model will be further explained below with reference to specific examples.

Example 1

As shown in fig. 1, 2 and 5, the present utility model provides a cylindrical battery 100a including a case 20, a battery cell 10a, and a cap 40.

The battery cell 10a is accommodated in the casing 20, and adopts a mode that two ends of the battery cell are provided with tab layers, one end of the battery cell extends out of the positive tab 121, and the other end extends out of the negative tab 122. The battery cell 10a is formed by winding a positive plate, a diaphragm and a negative plate, wherein a positive tab 121 extends from the positive plate to the outside of the battery cell 10a, and a negative tab 122 extends from the negative plate to the outside of the battery cell 10 a. The positive tab 121 includes multiple layers of tabs 14, each tab 14 extending from the pole piece position where it is located beyond the end face 11 of the cell 10 a. After the rubbing treatment, a first inclined surface 1211 is formed at one end of the positive electrode tab 121, which is far away from the battery cell 10 a. After the battery cell 10a is placed in the battery case 20, the positive tab 121 is welded and fixed to the bottom wall 21.

The housing 20 has an opening and a bottom wall 21 disposed opposite the opening, and the cap 40 is snapped onto the opening. The bottom wall 21 has a first surface 211 and a second surface 212 facing away from the first surface 211, a first boss 22 protruding from the second surface 212 is formed on the bottom wall 21, and a second inclined surface 221 is formed on the first boss 22. When the battery cell 10a is placed in the battery case 20, the first inclined surface 1211 of the positive electrode tab 121 is attached to the second inclined surface 221 of the first boss 22, so that the bottom wall 21 can be attached to the flattened appearance of the positive electrode tab 121.

It should be noted that, after the winding is completed, the battery cell 10a needs to knead and flatten the tab, that is, the tab is arranged and flattened by a certain rule or mode. The essence of the rubbing is to bend the end parts of all the tabs 14 along the height direction of the cell 10a toward the end face 11 to form a flat surface. The electrode lugs 14 on the inner side and the outer side of the battery cell 10a have a height difference and a layer number difference, and the electrode lug layers after being flattened are inclined planes relative to the end face 11.

As shown in fig. 4 and 5, in the present embodiment, the positive electrode tab 121 extends from the entire end face 11, each tab 14 has a connecting portion 141 for connecting the positive electrode tab and a bending portion 142 for bending, one end of the bending portion 142 is connected to the connecting portion 141, the other end extends in the height direction of the cell 10a and then is bent toward the end face 11, and the bending directions of all the tabs 14 are identical, so that the bending portions 142 of all the tabs 14 form a flat surface together, and the flat surface is the first inclined surface 1211.

The rubbing direction can be from inside to outside or from outside to inside. As shown in fig. 1, the cell 10a has a central axis 151, where "inner" means in a direction toward the central axis 151, and "outer" means in a direction away from the central axis 151. In this embodiment, the height of the pole ear 14 after being flattened is preferably gradually reduced from outside to inside in a rubbing manner, and correspondingly, the height of the first boss 22 is gradually increased from outside to inside. As shown in fig. 2, when the height of the first boss 22 gradually increases from the outside to the inside, a groove 25 for storing an electrolyte may be provided between the first boss 22 and the second boss 24.

Preferably, the second inclined surface 221 forms an angle with the first surface 211 of 3-25 °, in particular: the angle between the second inclined surface 221 and the first surface 211 is 3-9 °, 10-15 °, 16-21 °, or 22-25 °, for example, the angle between the second inclined surface 221 and the first surface 211 is 3 °, 6 °, 12 °, 18 °, 20 °, or 23 °, but not limited to the recited values, and other values not recited in the numerical range are equally applicable.

It can be appreciated that, in order to ensure that the positive electrode tab 121 and the bottom wall 21 are tightly fitted, the inclination directions and inclination angles of the first inclined surface 1211 and the second inclined surface 221 are substantially the same with respect to the first surface 211.

Preferably, as shown in fig. 3, the cell 10a has a central hole 15 penetrating therethrough along the height direction of the cell 10a, and the bottom wall 21 is formed with a liquid injection hole 23 communicating with the central hole 15 at a position corresponding to the central hole 15 for injecting the electrolyte into the cylindrical battery 100 a. Since the thickness of the bottom wall 21 is relatively thin, in order to prevent the opening of the liquid injection hole 23 from affecting the strength of the bottom wall 21, the second boss 24 is formed on the bottom wall 21 on the side of the bottom wall 21 having the second surface 212, and the liquid injection hole 23 extends from the bottom wall 21 and penetrates the second boss 24. Further, a plurality of reinforcing ribs 26 may be formed on the side of the bottom wall 21 having the first surface 211 to enhance the strength of the bottom wall 21.

In addition, when the electrolyte is injected, the electrolyte enters from the injection hole 23 of the bottom wall 21 and flows through the central hole 15, and in the case where the positive tab 121 protrudes from the entire end face 11, as shown in fig. 3, the second boss 24 may protrude into the central hole 15 to separate the tab 14 from the electrolyte, thereby preventing the tab 14 near the periphery of the central hole 15 from being torn by the electrolyte impact.

Preferably, for convenience of welding, the positive tab 121 in the present embodiment is made of a multi-layered aluminum foil, and the battery case 20 is an aluminum case, but is not limited to the case where the battery case 20 is a steel case.

As shown in fig. 1, the end of the cylindrical battery 100a extending out of the negative electrode lug 122 according to the present embodiment further includes a negative current collecting plate 30, and along the thickness direction of the negative current collecting plate 30, a third surface and a fourth surface are disposed opposite to each other, and the negative electrode lug 122 is welded and fixed on the third surface of the negative current collecting plate 30; a cap 40 sealed and fixed to the opening of the case 20, wherein a post through hole is formed in the cap 40 along the thickness direction of the cap 40, and a negative post 41 is installed in the post through hole in an insulating manner; wherein, one end of the negative electrode post 41 protrudes out of the post through hole and is welded and fixed on the fourth surface of the negative current collecting plate 30.

By welding and fixing the positive electrode tab 121 to the bottom wall 21, the positive current collecting plate is eliminated; by welding the negative current collecting plate 30 with the cap 40 through the negative electrode post 41, the bent portion of the negative current collecting plate 30 is eliminated. The cylindrical battery 100a in this embodiment can solve the problems of larger battery resistance and low energy density caused by the longer bending part of the structural member of the positive and negative current collecting plates 30 by eliminating the bending parts of the positive current collecting plates and the negative current collecting plates 30. Meanwhile, in the cylindrical battery 100a of this embodiment, by setting the inclined plane on the first boss 22 to make the lamination tab layer smooth, it is ensured that each tab area 12 can be laminated to the bottom wall 21, the lamination effect of the bottom of the housing 20 and the tab can be better improved, a larger overcurrent area can be ensured, and the battery resistance and the overcurrent temperature rise can be improved.

The cylindrical battery 100a of the present embodiment adopts the following assembly method:

(1) Winding the positive plate, the diaphragm and the negative plate into a battery cell 10a;

(2) Flattening the positive electrode tab 121 and the negative electrode tab 122;

(3) The negative electrode lug 122 is welded and fixed with the negative current collecting disc 30 by adopting a laser penetration welding mode;

(4) Placing the battery cell 10a into an aluminum shell, enabling the positive electrode lug 121 to prop against the bottom of the aluminum shell, and adopting laser penetration welding to fix the positive electrode lug 121 and the bottom of the aluminum shell in a welding manner;

(5) Sealing and fixing the cap 40 to the opening of the aluminum shell by means of laser welding;

(6) The welding head passes through the liquid injection hole 23 at the bottom of the aluminum shell and the central hole 15 of the battery cell 10a by adopting a resistance welding or torque welding mode to weld and fix the negative current collecting disc 30 and the negative electrode lug 122;

(7) And (5) injecting liquid, and sealing the liquid injection hole 23 after the liquid injection is completed.

Example 2

The present utility model provides a cylindrical battery 100b, unlike embodiment 1, the end face 11 of the battery 10b in this embodiment has at least one tab area 12 and at least one non-tab area 13, the tab area 12 and the non-tab area 13 are adjacently disposed, the tab area is a sector area, the tab of each tab area 12 is formed with a first inclined plane, the bottom wall 21 in this embodiment has at least one first boss 22, and each first boss 22 is formed with a second inclined plane 221.

As shown in fig. 6, the end face 11 in this embodiment may have two tab areas 12 and two non-tab areas 13, and the bottom wall 21 is correspondingly formed with two first bosses 22, and the second inclined plane 221 of each boss may be attached to the flattened appearance of the tab layer of each tab area 12.

The number of tab regions 12 is not limited in this embodiment, and may be specifically designed according to specific situations in practical applications.

For convenience of description, the above embodiment is described taking the case of welding and fixing the positive electrode tab and the bottom wall as an example, but is not limited to the case of welding and fixing the negative electrode tab and the bottom wall.

The utility model also provides electric equipment, the cylindrical battery used by the electric equipment is one of the embodiments, and the main design key point of the utility model is that the structure of the cylindrical battery is improved, and other structures of the electric equipment, such as an electric connection part and a mechanical structure part of the electric equipment are not repeated one by one.

The electric equipment can be an automobile, a mobile phone, portable equipment, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool and the like. The automobile can be a fuel oil automobile, a fuel gas automobile or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid electric automobile or a range-extended automobile and the like; spacecraft including airplanes, rockets, space planes, spacecraft, and the like; the electric toy includes fixed or mobile electric toys, such as a game machine, an electric car toy, an electric ship toy, and an electric airplane toy; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railroad power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete shakers, and electric planers, among others. The embodiment of the utility model does not limit the electric equipment in particular.

The battery cell provided by the embodiment of the utility model comprises a positive electrode plate, a negative electrode plate and a diaphragm. The positive electrode plate comprises a positive electrode current collector and a positive electrode active material layer, and the positive electrode active material layer is coated on the surface of the positive electrode current collector; the positive electrode current collector comprises a positive electrode coating area and a positive electrode lug connected to the positive electrode coating area, wherein the positive electrode coating area is coated with a positive electrode active material layer, and the positive electrode lug is not coated with the positive electrode active material layer. The negative electrode plate comprises a negative electrode current collector and a negative electrode active material layer, and the negative electrode active material layer is coated on the surface of the negative electrode current collector; the negative electrode current collector comprises a negative electrode coating area and a negative electrode tab connected to the negative electrode coating area, wherein the negative electrode coating area is coated with a negative electrode active material layer, and the negative electrode tab is not coated with the negative electrode active material layer. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, the positive electrode active material layer includes a positive electrode active material, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate or the like. The material of the anode current collector may be copper, the anode active material layer includes an anode active material, and the anode active material may be carbon or silicon, or the like. The separator may be made of PP (polypropylene) or PE (polyethylene).

It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations and modifications of the present utility model will be apparent to those of ordinary skill in the art in light of the foregoing description. It is not necessary here nor is it exhaustive of all embodiments. And obvious variations or modifications thereof are contemplated as falling within the scope of the present utility model.

Claims (11)

1. A cylindrical battery, comprising

The battery cell, opposite both ends stretch out and have tab layers, the tab layer polarity of both ends is opposite, the tab layer of at least one end is far away from one end of the said battery cell forms the first inclined plane;

the shell is provided with an opening and a bottom wall opposite to the opening, the bottom wall is provided with a first surface and a second surface which is opposite to the first surface, a first boss protruding out of the second surface is formed on the bottom wall, and a second inclined plane is formed on the first boss;

the battery cell is accommodated in the shell, the first inclined plane is attached to the second inclined plane, and the tab layer is welded and fixed with the bottom wall.

2. The cylindrical battery of claim 1, wherein the tab layer comprises a plurality of tabs formed with

The connecting part extends out of one end face of the battery cell from the pole piece in the battery cell;

one end of the bending part is connected to the connecting part, and the other end of the bending part extends along the height direction of the battery cell and then bends towards the end surface position;

the bending directions of all the tabs are consistent, so that the bending parts of all the tabs form a flat surface together, and the flat surface is the first inclined surface.

3. The cylindrical battery as in claim 2, wherein,

the end face is provided with at least one tab area and at least one non-tab area, the tab area and the non-tab area are adjacently arranged, the tab area is a sector area, and the tab layer of each tab area is provided with the first inclined plane;

the number of the first bosses is at least one, and each first boss is provided with the second inclined plane;

each tab area corresponds to one first boss.

4. The cylindrical battery according to claim 1, wherein,

the electric core is provided with a through center hole along the height direction of the electric core;

and a liquid injection hole is formed in the bottom wall corresponding to the position of the central hole, and the liquid injection hole is communicated with the central hole.

5. The cylindrical battery according to claim 4, wherein a second boss is formed on a side of the bottom wall having the second surface, and the liquid injection hole extends from the bottom wall and penetrates the second boss.

6. The cylindrical battery of claim 5, wherein the second boss extends into the central bore.

7. The cylindrical battery of claim 5, wherein said cell has a central axis, and wherein said first boss decreases in height from said central axis in a direction axially away from said central axis.

8. The cylindrical battery of claim 7, wherein a groove is provided between the first boss and the second boss.

9. The cylindrical battery according to any one of claims 1 to 8, wherein a plurality of reinforcing ribs are formed on the bottom wall on the side thereof having the first surface.

10. The cylindrical battery of claim 1, wherein one end of the cell extends out of the positive tab and the opposite end extends out of the negative tab, the first bevel is formed on the positive tab, and the positive tab and the bottom wall are welded together.

11. A powered device comprising a battery as claimed in any one of claims 1-10.