Battery and battery pack

Abstract

The utility model relates to the technical field of batteries, and discloses a battery and a battery pack, and the battery comprises a shell with an accommodating cavity; the insulating plate is movably arranged in the shell, the insulating plate divides the accommodating cavity in the shell into a first cavity body and a second cavity body, and the insulating plate is suitable for moving in the shell so as to adjust the sizes of the first cavity body and the second cavity body; the pole group is arranged in the first cavity; and the elastic piece is arranged in the second cavity, and the elastic piece is telescopically supported between one end, far away from the pole group, of the shell and the insulating plate. The accommodating cavity in the shell is divided into the first cavity and the second cavity by arranging the insulating plate, the pole group is arranged in the first cavity, and the elastic piece is arranged in the second cavity, so that when the volume of the pole group expands due to long-time use, the pole group pushes the insulating plate to move, and the insulating plate compresses the elastic piece; the volume of the second cavity is reduced and the volume of the first cavity is increased, so that the accommodating space of the pole group in the shell is enlarged, excessive extrusion between the pole group and the shell is avoided, and thermal runaway is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to batteries and battery packs. Background Art

[0002] With the popularization and application of batteries in industries such as electric vehicles, battery safety has received more and more attention. The battery is mainly composed of a closed shell and a pole group located inside the shell. The pole group is fixed in the shell to prevent the pole group from shaking in the shell. However, during the use of the battery, as the battery ages, the pole group inside the battery will expand and deform. In the early stage of battery design, there is often no extra space in the shell for the pole group to expand in volume, so the shell and the pole group squeeze each other. As the volume of the pole group continues to expand, the pressure in the shell is too high, and thermal runaway is likely to occur, which is highly dangerous. Utility Model Content

[0003] In view of this, the utility model provides a battery and a battery pack to solve the problem of mutual compression between the electrode group and the shell when the volume of the electrode group expands.

[0004] In a first aspect, the utility model provides a battery, comprising: a shell having a accommodating cavity; an insulating plate movably arranged inside the shell, the insulating plate dividing the accommodating cavity in the shell into a first cavity and a second cavity, the insulating plate being suitable for moving in the shell to adjust the size of the first cavity and the second cavity; a pole group arranged in the first cavity; an elastic member arranged in the second cavity, the elastic member being telescopically supported between one end of the shell away from the pole group and the insulating plate.

[0005] Beneficial effect: By arranging an insulating plate inside the shell, the accommodating cavity in the shell is divided into a first cavity and a second cavity. By arranging the pole group in the first cavity and the elastic member in the second cavity, the elastic member supports the insulating plate and the pole group. When the pole group expands in volume due to long-term use, the pole group pushes the insulating plate to move toward the direction of the second cavity. The insulating plate compresses the elastic member to reduce the volume of the second cavity and increase the volume of the first cavity, thereby expanding the accommodating space for the pole group in the shell, avoiding excessive squeezing of the pole group and the inner wall of the shell, thereby avoiding thermal runaway and improving the safety of the battery.

[0006] In an optional embodiment, the number of the elastic members is one or more.

[0007] Beneficial effects: when the number of elastic members is one, it is easy to assemble; when the number of elastic members is multiple, the volume of a single elastic member can be reduced, and the multiple elastic members have higher support stability for the insulation board.

[0008] In an optional embodiment, the elastic members are multiple in number, including a first elastic member and a plurality of second elastic members, the first elastic member is located on the axis of the shell, and the plurality of second elastic members are distributed at circumferential intervals around the first elastic member.

[0009] Beneficial effect: By setting a first elastic member at the axial position of the shell, the center position of the insulating plate is supported, and by setting a plurality of spaced second elastic members around the first elastic member, the connecting lines of the plurality of second elastic members form a circle, thereby increasing the balance of the elastic force supporting the insulating plate, avoiding the offset of the insulating plate when pushed by the pole group, thereby improving the stability of the insulating plate movement process and improving the battery quality.

[0010] In an optional embodiment, the elastic member is a spring.

[0011] Beneficial effects: The spring has good elastic deformation ability, is relatively common, low in cost and easy to use.

[0012] In an optional implementation, one end of the spring close to the insulating plate is configured as a hook, and the hook is hooked on the insulating plate.

[0013] Beneficial effect: By constructing one end of the spring close to the insulating plate as a hook, the spring is conveniently hooked onto the insulating plate through the hook, thereby improving the stability of the connection between the elastic member and the insulating plate and preventing the elastic member from being misaligned relative to the insulating plate, thereby further ensuring the smoothness of the movement of the insulating plate.

[0014] In an optional implementation, the insulating plate is made of rubber.

[0015] Beneficial effects: The rubber has good insulation and low cost, and the hook of the spring can be directly inserted into the rubber to achieve hanging, without setting up an additional hanging structure, simple processing and convenient operation.

[0016] In an optional implementation, one end of the elastic member away from the insulating plate is connected to a fixing seat, and the fixing seat is fixedly connected to the shell.

[0017] Beneficial effect: By fixing a fixing seat on the shell and connecting an elastic member to the fixing seat, the elastic member is fixedly connected to the shell, thereby ensuring the stability of the relative position of the elastic member and the shell, avoiding displacement of the elastic member, further ensuring stable support of the insulating plate by the elastic member, ensuring the stability of the pole group during the expansion process, and avoiding thermal runaway.

[0018] In an optional embodiment, a pole is provided on one end of the shell away from the second cavity, and the pole is insulated and connected to the shell, and the pole group includes: a first pole piece, electrically connected to the pole; a second pole piece, stacked with the first pole piece and electrically connected to the shell; and a diaphragm, arranged between the first pole piece and the second pole piece to separate the first pole piece from the second pole piece.

[0019] Beneficial effect: By arranging the first electrode sheet and the second electrode sheet to be stacked, and placing the diaphragm between the first electrode sheet and the second electrode sheet to separate the two, direct contact between the first electrode sheet and the second electrode sheet is avoided, thereby preventing the positive and negative electrode sheets from short-circuiting inside the battery. The first electrode sheet is electrically connected to the pole and the second pole sheet is electrically connected to the shell, so that the positive and negative electrodes of the electrode group are respectively led out, and the insulated connection between the pole and the shell can further avoid short-circuiting of the positive and negative electrodes of the battery, thereby ensuring the safety of the battery.

[0020] In an optional embodiment, the first pole piece and the second pole piece both include: a pole piece body and a connecting portion, the connecting portion is formed by extending outward from a partial area of ​​the edge of the pole piece body, the pole piece body of the first pole piece is stacked with the pole piece body of the second pole piece, the connecting portion of the first pole piece is connected to the pole column, and the connecting portion of the second pole piece is connected to the shell.

[0021] Beneficial effects: The pole piece includes a pole piece body and a connecting portion, the pole piece body is stacked as the main part of the pole piece, and the connecting portion of the pole piece body at the extended part is used to connect with the pole or the shell, which has a simple structure and is easy to operate.

[0022] In a second aspect, the utility model further provides a battery pack, comprising: the above-mentioned battery. Because the battery pack comprises the battery, it has the same effect as the battery, and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 This is a schematic diagram of the structure of a battery according to an embodiment of the utility model;

[0025] Figure 2 for Figure 1 A top view of the second cavity of the battery shown;

[0026] Figure 3It is a schematic structural diagram of a pole piece according to an embodiment of the utility model.

[0027] Description of reference numerals:

[0028] 1. Shell; 101. First cavity; 102. Second cavity; 110. Pole; 2. Insulating plate; 3. Pole group; 301. First pole piece; 302. Second pole piece; 303. Diaphragm; 310. Pole piece body; 320. Connecting part; 4. Elastic member; 401. First elastic member; 402. Second elastic member; 410. Fixing seat. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.

[0030] Combine the following Figures 1 to 3 , describing an embodiment of the utility model.

[0031] According to an embodiment of the utility model, on the one hand, a battery is provided, comprising: a housing 1, an insulating plate 2, a pole group 3 and an elastic member 4. The housing 1 has a receiving cavity; the insulating plate 2 is movably arranged inside the housing 1, and the insulating plate 2 divides the receiving cavity in the housing 1 into a first cavity 101 and a second cavity 102, and the insulating plate 2 is suitable for moving in the housing 1 to adjust the size of the first cavity 101 and the second cavity 102; the pole group 3 is arranged in the first cavity 101; the elastic member 4 is arranged in the second cavity 102, and the elastic member 4 is telescopically supported between the end of the housing 1 away from the pole group 3 and the insulating plate 2.

[0032] In the battery implemented in this embodiment, an insulating plate 2 is arranged inside the shell 1 to divide the accommodating cavity in the shell 1 into a first cavity 101 and a second cavity 102. By arranging the electrode group 3 in the first cavity 101 and the elastic member 4 in the second cavity 102, the elastic member 4 plays a supporting role for the insulating plate 2 and the electrode group 3. When the electrode group 3 expands in volume due to long-term use, the electrode group 3 pushes the insulating plate 2 to move toward the direction of the second cavity 102. The insulating plate 2 compresses the elastic member 4 to reduce the volume of the second cavity 102 and increase the volume of the first cavity 101, thereby expanding the accommodating space for the electrode group 3 in the shell 1, avoiding excessive squeezing of the electrode group 3 and the inner wall of the shell, thereby avoiding thermal runaway and improving the safety of the battery.

[0033] It should be noted that the elastic member 4 is disposed between the housing 1 and the insulating plate 2. Figure 1 The elastic member 4 extends and contracts in the "X" direction indicated by the arrow in the middle. At the beginning of battery manufacturing, the elastic member 4 provides a thrust to the insulating plate 2 toward the first cavity 101. The elastic member 4 supports the insulating plate 2 and the electrode group 3 located on the side of the insulating plate 2 away from the elastic member 4. One end of the electrode group 3 abuts against the first end of the shell 1 and the other end abuts against the side of the insulating plate 2 facing the first cavity 101, thereby fixing the electrode group 3 in the first cavity 101 to prevent the electrode group 3 from shaking in the shell; the elastic member 4 is supported between the second end of the shell 1 and the insulating plate 2; when the volume of the electrode group 3 expands due to battery aging, the electrode group 3 moves along Figure 1 The insulating plate 2 is pushed in the "X" direction indicated by the arrow, and the insulating plate 2 moves in the "X" direction in the shell 1, that is, the insulating plate 2 can move along the extension direction of the center line of the shell 1 to change the size of the first cavity 101 and the second cavity 102. As the volume of the second cavity 102 decreases, the volume of the first cavity 101 increases, and the pole group 3 moves along the Figure 1 The first end and the second end are two opposite ends of the housing 1, specifically, the length of the pole group 3 is extended by the "X" direction indicated by the arrow. Figure 1 The two ends of the "X" direction pointed by the arrows in the middle.

[0034] In one embodiment, the number of elastic members 4 is one or more. The number of elastic members 4 can be one or more. When the number of elastic members 4 is one, it is easy to assemble; when the number of elastic members 4 is more than one, the volume of a single elastic member 4 can be reduced, and the support stability of the insulating plate 2 by the multiple elastic members 4 is higher. Among them, when the number of elastic members 4 is one, it is preferably set at a position that coincides with the axis of the battery.

[0035] In one embodiment, the number of elastic members 4 is multiple, including a first elastic member 401 and a plurality of second elastic members 402, the first elastic member 401 is located on the axis of the housing 1, and the plurality of second elastic members 402 are distributed at intervals around the circumference of the first elastic member 401. By setting a first elastic member 401 at the axis position of the housing 1, the center position of the insulating plate 2 is supported, and by setting a plurality of spaced second elastic members 402 around the first elastic member 401, the connecting line of the plurality of second elastic members 402 forms a circle, which increases the balance of the supporting force of the elastic member 4 on the insulating plate 2, and avoids the insulating plate 2 from being offset when pushed by the pole group 3, thereby improving the stability of the moving process of the insulating plate 2, avoiding the inclination of the pole group 3, and improving the quality of the battery. Preferably, the plurality of second elastic members 402 are distributed at equal intervals. Among them, the first elastic member 401 and the second elastic member 402 are the same elastic members, and the difference lies in the different positions of setting.

[0036] Preferably, further combined Figure 2 As shown, there are four second elastic members 402 , plus a first elastic member 401 at the center, a total of five elastic members 4 support the insulating plate 2 , which has good stability and can avoid waste caused by too many elastic members 4 and excessive battery weight.

[0037] In one embodiment, the elastic member 4 is a spring. The spring has good elastic deformation ability, is relatively common, low in cost, and easy to use. It can be understood that, as an alternative embodiment, the elastic member 4 can also be an elastic member such as a rubber ring, an elastic sleeve, etc.

[0038] In one embodiment, one end of the spring close to the insulating plate 2 is configured as a hook, and the hook is hooked on the insulating plate 2. By configuring one end of the spring close to the insulating plate 2 as a hook, it is convenient for the spring to be hooked on the insulating plate 2 through the hook, thereby improving the stability of the connection between the elastic member 4 and the insulating plate 2, preventing the elastic member 4 from being misaligned relative to the insulating plate 2, and further ensuring the stability of the moving process of the insulating plate 2.

[0039] In one embodiment, the insulating plate 2 is made of rubber, which has good insulation and low cost, and the hook of the spring can be directly inserted into the rubber to achieve hanging without setting an additional hanging structure, which is simple to process and easy to operate.

[0040] In one embodiment, one end of the elastic member 4 away from the insulating plate 2 is connected to a fixing seat 410, and the fixing seat 410 is fixedly connected to the housing 1. By fixing the fixing seat 410 to the housing 1, and connecting the elastic member 4 to the fixing seat 410, the elastic member 4 is fixedly connected to the housing 1, thereby ensuring the stability of the relative position between the elastic member 4 and the housing 1, avoiding displacement of the elastic member 4, further ensuring stable support of the insulating plate 2 by the elastic member 4, ensuring the stability of the pole group 3 during the expansion process, and avoiding thermal runaway.

[0041] In one embodiment, a pole 110 is disposed on one end of the housing 1 away from the second cavity 102, that is, the pole 110 is disposed on the first end of the housing 1, and the pole 110 is insulated and connected to the housing 1. The pole group 3 includes: a first pole piece 301, a second pole piece 302, and a diaphragm 303. The first pole piece 301 is electrically connected to the pole 110; the second pole piece 302 is stacked with the first pole piece 301 and is electrically connected to the housing 1; and the diaphragm 303 is disposed between the first pole piece 301 and the second pole piece 302 to separate the first pole piece 301 from the second pole piece 302. The first electrode piece 301 and the second electrode piece 302 are stacked and the diaphragm 303 is placed between the first electrode piece 301 and the second electrode piece 302 to separate the two, thereby avoiding direct contact between the first electrode piece 301 and the second electrode piece 302, thereby preventing the positive and negative electrodes from short-circuiting inside the battery. The first electrode piece 301 is electrically connected to the pole 110 and the second pole piece 302 is electrically connected to the shell 1, so that the positive and negative electrodes of the electrode group are respectively led out, and the insulated connection between the pole 110 and the shell 1 can further avoid short-circuiting of the positive and negative electrodes of the battery, thereby ensuring the safety of the battery. Specifically, the first pole piece 301 is a positive pole piece, the second pole piece 302 is a negative pole piece, the pole post 110 electrically connected to the first pole piece 301 is the positive pole post of the battery, and the shell 1 as a whole serves as the negative pole of the battery; it can be understood that, as an alternative embodiment, the first pole piece 301 can also be a negative pole piece, and the second pole piece 302 can be a positive pole piece. In this case, the pole post 110 serves as the negative pole and the shell 1 serves as the positive pole.

[0042] In one embodiment, the first pole piece 301 and the second pole piece 302 both include: a pole piece body 310 and a connecting portion 320, the connecting portion 320 is formed by extending outward from a portion of the edge of the pole piece body 310, the pole piece body 310 of the first pole piece 301 is stacked with the pole piece body 310 of the second pole piece 302, the connecting portion 320 of the first pole piece 301 is connected to the pole 110, and the connecting portion 320 of the second pole piece 302 is connected to the housing 1. The outward extension refers to extending in a direction away from the center of the pole piece body 310. Figure 3 The pole piece shown can be the first pole piece 301 or the second pole piece 302. The pole piece body 310 includes a metal layer and an active material coated on the metal layer, and the connecting portion 320 is an extension of the metal layer to facilitate electrical connection with the pole 110 or the housing 1. Specifically, the positive pole piece is coated with a positive active material, and the negative pole piece is coated with a negative active material. By setting the pole piece to include the pole piece body 310 and the connecting portion 320, the pole piece body 310 is stacked as the main part of the pole piece, and the connecting portion 320 of the pole piece body 310 at the extension is used to connect with the pole 110 or the housing 1, which has a simple structure and is easy to operate.

[0043] In one embodiment, there are multiple first pole pieces 301, and multiple second pole pieces 302. The first pole pieces 301 and the second pole pieces 302 are stacked in sequence. The diaphragm 303 is a whole piece of diaphragm that is bent to separate each adjacent first pole piece 301 from the second pole piece 302. The connecting portions 320 of multiple first pole pieces 301 are connected and then connected to the pole 110, thereby connecting the multiple first pole pieces 301 to the pole 110. The connecting portions 320 of the multiple second pole pieces 302 are directly connected to the shell 1, thereby electrically connecting the multiple second pole pieces 302 to the shell 1. It should be noted that as the battery ages, the volume of the active material on the pole piece increases or the gaps between the active material particles increase, which will lead to an increase in the thickness of the pole piece, thereby leading to an increase in the volume of the pole group. When the first pole piece 301 and the second pole piece 302 are connected as shown in the following example, Figure 3 When stacked in the manner shown in the figure, after the thickness of the pole piece increases, the pole group becomes larger in size along the stacking direction, that is, along the Figure 3 As shown, the size in the X direction increases. Therefore, by setting the insulating plate 2, the space in the battery is divided into two cavities distributed along the X direction. When the direction of increase in the size of the pole group is consistent with the moving direction of the insulating plate 2, it can effectively provide expansion space for the expansion of the pole group 3 to avoid thermal runaway.

[0044] In one embodiment, the battery is a cylindrical battery, the cross section of the housing 1 is circular, and accordingly, the insulating plate 2 is circular, and the pole piece body 310 is circular. It can be understood that the battery can also be a square battery or other shapes, and the shapes of the insulating plate 2 and the pole piece body 310 can be adapted thereto.

[0045] In this embodiment, the electrode group 3 is a stacked structure as a whole, the negative electrode sheet is connected to the shell 1, and the positive electrode sheet is connected together and fixed on the pole 110 at the first end of the shell 1. When the battery expands after long-term use, the length of the electrode group 3 along the stacking direction increases, and the electrode group 3 located in the first cavity 101 pushes the insulating plate 2 to move toward the second end of the shell 1, compressing the elastic member 4 in the second cavity, the volume of the second cavity 102 is reduced, and the volume of the first cavity 101 is increased, thereby expanding a larger space to accommodate the electrode group 3 to avoid thermal runaway.

[0046] According to an embodiment of the present invention, on the other hand, a battery pack is provided, comprising: the above-mentioned battery. The battery pack comprises a plurality of batteries.

[0047] Although the embodiments of the present invention are described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A battery, characterized in that: include: A housing having a receiving cavity; an insulating plate, movably disposed inside the shell, the insulating plate dividing the accommodating cavity in the shell into a first cavity and a second cavity, and the insulating plate is suitable for moving inside the shell to adjust the size of the first cavity and the second cavity; A pole group, arranged in the first cavity; An elastic member is arranged in the second cavity, and the elastic member is telescopically supported between an end of the shell away from the pole group and the insulating plate.

2. The battery according to claim 1, characterized in that The number of the elastic member is one or more.

3. The battery according to claim 2, characterized in that There are multiple elastic members, including a first elastic member and a plurality of second elastic members. The first elastic member is located on the axis of the shell, and the plurality of second elastic members are distributed at intervals in the circumferential direction around the first elastic member.

4. The battery according to claim 1, characterized in that The elastic member is a spring.

5. The battery according to claim 4, characterized in that One end of the spring close to the insulating plate is configured as a hook portion, and the hook portion is hooked on the insulating plate.

6. The battery according to claim 5, characterized in that The insulating plate is made of rubber.

7. The battery according to claim 1, characterized in that One end of the elastic member away from the insulating plate is connected to a fixing seat, and the fixing seat is fixedly connected to the shell.

8. The battery according to any one of claims 1 to 7, characterized in that A pole is provided on one end of the shell away from the second cavity, and the pole is insulated and connected to the shell. The pole group includes: A first pole piece, electrically connected to the pole; A second pole piece, stacked with the first pole piece and electrically connected to the housing; A diaphragm is disposed between the first pole piece and the second pole piece to separate the first pole piece from the second pole piece.

9. The battery according to claim 8, characterized in that The first pole piece and the second pole piece both include: a pole piece body and a connecting portion, wherein the connecting portion is formed by extending outward from a partial area of ​​the edge of the pole piece body, the pole piece body of the first pole piece is stacked with the pole piece body of the second pole piece, the connecting portion of the first pole piece is connected to the pole column, and the connecting portion of the second pole piece is connected to the shell.

10. A battery pack, characterized in that: include: The battery according to any one of claims 1 to 9.

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