Cover plate and lithium ion battery

Abstract

The utility model discloses a cover plate, which is used for sealing a lithium ion battery and comprises a cover plate body, a cover plate cover plate and a cover plate cover plate, the flow guide part is arranged on the inner side of the cover plate, the flow guide part is provided with a flow channel extending in the first direction, the flow channel is communicated with the liquid injection hole, the flow guide part is provided with a plurality of outlets, and the outlets are dispersed in the side, away from the cover plate body, of the flow guide part. The utility model also discloses a lithium ion battery using the cover plate. The cover plate is provided with the flow guide part, and during liquid supplementation, electrolyte can enter the battery shell from the outlets of the flow guide part, so that the electrolyte directly flows into each position of the battery cell, the electrolyte can fully infiltrate into the pores of the pole piece, the infiltration of the battery cell is accelerated, and the liquid injection efficiency is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of lithium battery, specifically is a cover plate and lithium ion battery. BACKGROUND

[0002] With the market's capacity requirement of energy storage system, battery is bigger and bigger, a energy storage battery advancement with "big capacity" as the prelude quietly opens the curtain, 300Ah+ battery from different enterprises appear on the stage, 305Ah, 314Ah, 320Ah, 325Ah etc. different specifications of energy storage battery promote a capacity race, accelerate the replacement of 280Ah energy storage battery. At the same time, 500+, 600+ Ah battery also gradually begin to research, large battery has become the trend of energy storage battery development.

[0003] For large capacity battery, with the increase of size, the increase of liquid injection amount, the traditional lithium ion battery is injected through the liquid injection hole on the cover plate, the electrolyte is flowed into the battery shell under the action of gravity, the electrolyte is deposited at the bottom of the shell, and the electrolyte is infiltrated from bottom to top by capillary force, the electrolyte is difficult to infiltrate the battery in a limited time, the injection efficiency is low, and the injection abnormality and overflow often occur. UTILITARIAN CONTENT

[0004] In order to overcome the defects in the prior art, the utility model provides a cover plate and lithium ion battery, the cover plate is provided with a flow guide piece, when supplementing liquid, the electrolyte can enter the battery shell from the multiple outlets of the flow guide piece, so that the electrolyte directly flows into each position of the battery, which is beneficial to the full infiltration of the electrolyte into the pole piece pores, accelerates the infiltration of the battery, and improves the injection efficiency.

[0005] In order to achieve the above purpose, the utility model adopts the technical scheme of a cover plate for sealing lithium ion battery, comprising:

[0006] The cover plate body is provided with a liquid injection hole;

[0007] The flow guide piece is arranged on the inner side of the cover plate body, the flow guide piece has a flow channel extending in the first direction, the flow channel is communicated with the liquid injection hole, the flow guide piece is provided with multiple outlets, and the outlets are dispersed on the side of the flow guide piece away from the cover plate body.

[0008] Through the above technical scheme, when the battery is sealed by using the above cover plate and liquid injection, the electrolyte flows into the flow channel of the flow guide piece from the liquid injection hole, and enters the battery shell through the multiple outlets of the flow guide piece, so that the electrolyte directly flows into each position of the battery, so that the electrolyte can fully infiltrate into the pole piece pores before being filled, accelerate the infiltration of the battery, and improve the injection efficiency.

[0009] Furthermore, the flow guide includes a groove extending in at least one direction, the open side of which is connected to the cover body, forming a liquid flow path between the groove and the cover body. The assembly is completed by sealing the groove to the cover body, making it convenient to retrofit lithium-ion batteries that are currently available on the market and do not have a flow guide.

[0010] Furthermore, the flow guide comprises at least two first tubes extending along the first direction, at least one second tube connected between the at least two first tubes, the inner lumens of the first tubes and the second tubes communicating with each other, the inner lumens of the first tubes and the second tubes forming the flow channel. The first tubes are spaced apart and arranged perpendicular to the first direction, and the second tubes are spaced apart and arranged along the first direction.

[0011] Furthermore, the flow guide is provided with at least two outlets distributed along the first direction, and at least two outlets distributed perpendicular to the first direction. The first direction is the length direction of the battery housing, which is perpendicular to the first direction, which is the width direction of the battery housing.

[0012] Furthermore, the size of the outlet increases gradually from the center of the guide member toward the periphery. The electrolyte enters the flow channel of the guide member through the injection hole, and then flows into the battery housing from each outlet in sequence through the flow channel. The electrolyte flows out of the outlet closest to the injection hole first. If the flow rate of the outlet closest to the injection hole is large, a large amount of electrolyte will flow out directly from the outlet closest to the injection hole, resulting in a slower speed at which the electrolyte fills the flow channel. Conversely, reducing the size of the outlet closest to the injection hole can allow the electrolyte to fill the flow channel of the guide member more quickly, thereby allowing the electrolyte to flow out of each outlet more quickly.

[0013] Furthermore, the spacing between adjacent outlets decreases from the center of the flow guide toward the periphery. Electrolyte flows out first from outlets near the injection hole. A higher density of outlets near the injection hole results in more electrolyte flowing out of these outlets, which slows down the flow channel. Specifically, outlets closer to the ends wait longer for electrolyte to arrive. Conversely, decreasing the density of outlets near the injection hole helps the flow channel fill faster.

[0014] Furthermore, the cover plate body and the flow guide are integrally formed, and the integrally formed design makes the overall sealing of the cover plate stronger.

[0015] A lithium-ion battery uses the above-mentioned cover plate to seal a battery cell in a battery casing.

[0016] By means of the above technical solution, the beneficial effects of the present invention are as follows:

[0017] 1. The present application sets a flow guide on the cover body. The flow guide has a flow channel and multiple outlets. The flow channel of the flow guide is connected to the injection hole of the cover body. During injection, the electrolyte flows through the flow channel of the flow guide through each outlet, thereby achieving direct flow of the electrolyte into various positions of the battery cell, which is conducive to the electrolyte fully infiltrating into the pores of the electrode, accelerating the infiltration of the battery cell, and improving the injection efficiency;

[0018] 2. The size of the outlet of the flow guide member in this application increases gradually from the center of the flow guide member to both ends. That is, the outlet at the center of the flow guide member is the smallest. This prevents the electrolyte from flowing too much in the outlet near the injection hole, thereby ensuring that the electrolyte quickly fills the flow channel of the flow guide member.

[0019] 3. In this application, the density of the outlet of the guide member increases from the center of the guide member to both ends, that is, the density of the outlet at the center of the guide member is the smallest, avoiding excessive flow of the electrolyte in the outlet near the injection hole, thereby ensuring that the electrolyte quickly fills the flow channel of the guide member.

[0020] In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 This is a schematic diagram of the overall structure of the cover plate in the embodiment of the present utility model;

[0023] Figure 2 This is a structural diagram of the cover body in an embodiment of the present utility model;

[0024] Figure 3 This is a schematic structural diagram of the flow guide member in an embodiment of the present utility model;

[0025] Figure 4 It is a structural diagram of a lithium-ion battery in an embodiment of the present utility model.

[0026] The figure numbers of the above drawings are: 1. cover body; 11. liquid injection hole; 2. flow guide; 21. outlet; 22. first groove; 23. second groove; 24. flow channel; 3. battery housing. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0028] It should be noted that, in the description of this utility model, the terms "first," "second," etc., are used solely for descriptive purposes and to distinguish similar objects. There is no order of precedence between the two, nor should they be construed as indicating or implying relative importance. Furthermore, in the description of this utility model, unless otherwise specified, "plurality" means two or more.

[0029] Example: Combination Figure 1-4 As shown, embodiment 1 discloses a cover plate for sealing a lithium-ion battery, comprising:

[0030] The cover body 1 is provided with a liquid injection hole 11. After the battery is assembled, electrolyte is injected into the battery housing 3 through the liquid injection hole 11 for absorption by the battery cell. The cover body 1 is also provided with a terminal 12, which is used to connect the positive / negative poles of the battery cell in the battery housing 3.

[0031] A flow guide 2 is provided on the inner side of the cover body 1. The flow guide 2 has a flow channel 24, and the flow channel 24 is connected to the injection hole 11. A plurality of outlets 21 are provided on the side of the flow guide 2 facing away from the cover body 1. When the battery is assembled and injected, the electrolyte enters the flow channel 24 of the flow guide 2 through the injection hole 11, and then flows out from each of the outlets 21 into the battery housing 3 through the flow channel 24. This enables the electrolyte to flow directly into various positions of the battery cell, so that the electrolyte can fully infiltrate the electrode pores before being filled, which is conducive to the electrolyte fully infiltrating the electrode pores, accelerating the infiltration of the battery cell, and improving the injection efficiency.

[0032] In the present application, the flow guide 2 includes two first grooves 22 spaced apart from each other. The first grooves 22 extend along the first direction. A second groove 23 is connected between the two first grooves. The first groove 22 and the second groove 23 are connected, and the second groove 23 is close to the center of the first groove 22. The open sides of the first groove 22 and the second groove 23 are connected to the cover body 1, and a liquid flow channel is formed between the cover body 1 and the first groove 22 and the second groove 2. The liquid injection hole 11 is located at the center of the second groove 23. A first outlet group is provided on the first groove 22, and the outlets in the first outlet group are spaced apart along the first direction, which is the length direction of the cover body 1. The size of the outlets 21 in the first outlet group increases from the center of the first groove 22 to both ends, and the spacing between the outlets 21 decreases from the center of the first groove 22 to both ends. A second outlet group is provided on the second groove 23, and the outlets in the second outlet group are spaced apart perpendicular to the first direction. The sizes of the outlets 21 in the second outlet group gradually increase from the center of the second groove 23 toward both ends, and the spacing between the outlets 21 gradually decreases from the center of the second groove 23 toward both ends. That is, the outlets 21 near the center of the first groove 22 or the second groove 23 are the smallest, and the density of the outlets 21 at the center of the first groove 22 or the second groove 23 is the lowest.

[0033] During injection, electrolyte first flows out of the outlets 21 near the injection hole 11. If the flow rate of the outlets 21 near the injection hole 11 is large, a large amount of electrolyte will flow directly out of the outlets 21 near the injection hole 11, resulting in a slower rate of electrolyte filling the flow channel 24. Conversely, reducing the size and density of the outlets 21 near the injection hole 11 can reduce the amount of electrolyte flowing out of the outlets 21 near the injection hole 11, allowing the electrolyte to fill the flow channel 24 of the flow guide 2 more quickly, thereby allowing the electrolyte to flow out of each outlet 21 more quickly.

[0034] Compared to traditional lithium-ion batteries, which inject electrolyte through the injection hole on the cover plate, the electrolyte flows into the battery housing 3 under the action of gravity. After the electrolyte is deposited on the bottom of the housing, it infiltrates the battery cell from bottom to top through capillary force. This makes it difficult for the electrolyte to infiltrate the battery cell within a limited time, resulting in low injection efficiency. The present application directly delivers the electrolyte to different positions of the battery cell through the guide member 2, which is conducive to the electrolyte fully infiltrating the pores of the electrode, accelerating the infiltration of the battery cell, increasing the cycle life of the battery cell, and improving the injection efficiency.

[0035] In order to ensure the sealing performance of the cover plate as a whole 1, the cover plate body 1 and the flow guide 2 are integrally formed.

[0036] Optionally, the flow guide 2 may be provided with more first grooves 22 and second grooves 23 to make the electrolyte injection more uniform.

[0037] Optionally, the first groove 22 and the second groove 23 can be replaced by a tube body with an inner cavity, and the inner cavity of the tank body serves as the flow channel.

[0038] The guide member 2 can also be a whole box body, the inner cavity of the box body is the flow channel, one side of the box body is fixedly connected to the cover body 1, so that the injection hole 11 is connected to the inner cavity of the box body, and several outlets 21 are set on the side of the box body away from the cover body 1.

[0039] The second embodiment discloses a lithium-ion battery, which uses the above-mentioned cover plate to seal the battery cell in the battery housing 3 .

[0040] The present invention uses specific embodiments to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A cover plate for sealing a lithium-ion battery, characterized in that: include: A cover plate body, wherein the cover plate body is provided with a liquid injection hole; The flow guide is arranged on the inner side of the cover body, and the flow guide has a flow channel extending along the first direction, the flow channel is connected to the injection hole, and the flow guide is provided with multiple outlets, which are dispersed on the side of the flow guide away from the cover body.

2. The cover plate according to claim 1, wherein: The flow guide comprises a groove extending in at least one direction, an open side of the groove is connected to the cover plate body, and a liquid flow channel is formed between the groove and the cover plate body.

3. The cover plate according to claim 1, wherein: The flow guide includes at least two first tubes extending along the first direction, at least one second tube is connected between the at least two first tubes, the inner cavities of the first tube and the second tube are connected, and the inner cavities of the first tube and the second tube are the flow channel.

4. The cover plate according to any one of claims 1 to 3, characterized in that: The flow guide is provided with at least two outlets distributed along the first direction, and at least two outlets distributed perpendicular to the first direction.

5. The cover plate according to claim 4, wherein: The size of the outlet increases gradually from the center of the guide member to the surrounding areas.

6. The cover plate according to claim 5, wherein: The interval between two adjacent outlets decreases gradually from the center of the guide member to the surrounding areas.

7. The cover plate according to claim 1, wherein: The cover plate body and the flow guide are integrally formed.

8. A lithium ion battery, characterized in that: The lithium-ion battery uses the cover plate according to any one of claims 1 to 7 to seal the battery cell in the battery casing.

Images