CN219843017U

CN219843017U - Battery for test

Info

Publication number: CN219843017U
Application number: CN202320366034.7U
Authority: CN
Inventors: 区彩霞; 吴小娟; 贾晨晓
Original assignee: Eve Energy Co Ltd
Current assignee: Eve Energy Co Ltd
Priority date: 2023-03-01
Filing date: 2023-03-01
Publication date: 2023-10-17
Anticipated expiration: 2033-03-01

Abstract

The utility model discloses a battery for testing, comprising: a housing having a bottom surface in a height direction and two side surfaces in a length direction; the battery cell is placed in the shell, a third lug is arranged on the battery cell, and the third lug, the positive pole lug and the negative pole lug on the battery cell are arranged on different sides of the battery cell; and the third pole is arranged on the bottom surface or one of the side surfaces and is connected with the third pole ear. The battery for testing can conveniently test the lithium precipitation condition of the battery, and avoid the condition of damaging the explosion-proof valve.

Description

Battery for test

Technical Field

The utility model relates to the technical field of batteries, in particular to a battery for testing.

Background

The lithium ion battery has the advantages of high energy density, quick charge and discharge, long cycle life, no pollution and the like, and is widely applied to the fields of portable electronic equipment, communication, energy storage and electric automobiles. With the technical development of lithium ion batteries, the performance requirements of various industries are higher and higher, so that the development test and evaluation of the electrochemical performance of new electrode materials and battery systems of the batteries are required.

When the battery is charged at low temperature or high rate, there may be a problem that lithium ions cannot be timely intercalated between graphite layers after reaching the negative electrode, and lithium precipitation occurs, i.e., a polarization phenomenon caused by limited kinetics. Therefore, in order to better study various electrochemical performances of the battery, reference electrodes are often introduced, and the potentials of the positive electrode and the negative electrode relative to the reference electrodes and the potential changes thereof under different test working conditions are tested respectively.

In the prior art, when lithium precipitation condition test is performed when a battery is charged, after preparation of the battery is completed, a copper wire is connected to a negative electrode plate and directly penetrates out of an explosion-proof valve on a cover plate to be electrically connected with test equipment, so that the test mode can cause damage of the explosion-proof valve.

Disclosure of Invention

To solve at least one of the problems in the prior art, according to one aspect of the present utility model, there is provided a battery for testing, comprising: a housing having a bottom surface in a height direction and two side surfaces in a length direction; the battery cell is arranged in the shell, a third lug is arranged on the battery cell, and the third lug, the positive electrode lug and the negative electrode lug on the battery cell are arranged on different sides of the battery cell; and the third pole is arranged on the bottom surface or one of the side surfaces and is connected with the third pole ear.

Like this, through setting up the third post on the casing to set up the third ear on the electric core, and the third ear set up in with anodal utmost point ear and negative pole utmost point ear locate the different sides of electric core, after accomplishing the connection of third ear and third post, for example welded connection, can regard as the reference electrode, cooperate anodal post and negative pole post to test, thereby avoided setting up the reference electrode in the apron, lead to destroying the condition of explosion-proof valve.

In some embodiments, the third pole is disposed on one of the sides.

In some embodiments, the third ear and the third pole are welded.

In some embodiments, the third electrode tab includes a first conductive region, a coating region, and a second connection region, the first conductive region being connected to the negative electrode tab, the coating region being coated with an insulating material, the second connection region being connected to the third electrode tab.

In some embodiments, the material of the third pole is lithium, platinum, or copper.

In some embodiments, the material of the third pole is copper.

In some embodiments, the third ear has a thickness of between 0.15 and 0.25 mm.

In some embodiments, the third ear has a length of between 1.8cm and 2.2 cm.

Drawings

Fig. 1 is a schematic structural diagram of a test battery according to an embodiment of the present utility model;

FIG. 2 is an exploded view of the test cell of FIG. 1;

FIG. 3 is a schematic view of a winding core according to an embodiment of the present utility model;

FIG. 4 is an exploded view of the winding core of FIG. 3;

FIG. 5 is a schematic view of another embodiment of a winding core;

FIG. 6 is an exploded view of the winding core of FIG. 5;

fig. 7 is a schematic structural view of the third ear in fig. 2.

Wherein the reference numerals have the following meanings:

100-test battery, 10-shell, 11-large face, 12-side face, 13-bottom face, 14-cover plate, 15-positive pole, 16-negative pole, 17-mounting hole, 20-electric core, 21-winding core, 211-diaphragm, 212-negative pole piece, 213-positive pole piece, 22-positive pole lug, 23-negative pole lug, 24-third lug, 241-first conductive area, 242-coating area, 243-second conductive area and 30-third pole.

Detailed Description

For a better understanding and implementation, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the drawings in the embodiments of the present utility model.

In the description of the present utility model, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, merely to facilitate description of the present utility model and simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used herein in the description of the utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model.

The utility model is described in further detail below with reference to the accompanying drawings.

When the charging performance of the battery is tested, the battery voltage tested is the difference between the positive electrode potential and the negative electrode potential. When the voltage of the lithium battery is changed under the condition of passing current, the potential difference between the positive electrode and the negative electrode is obtained, but the real-time potential change condition of the positive electrode and the negative electrode cannot be obtained. In order to monitor the real-time change of the positive electrode and negative electrode potential of the lithium battery under the condition of passing current, so as to enhance the understanding of the performance characteristics and the performance change of the lithium battery, a third electrode, namely a reference electrode, needs to be introduced into the lithium battery.

Referring to fig. 1 to 7, a test battery 100 according to an embodiment of the utility model includes a housing 10, a battery cell 20, and a third pole 30.

Referring to fig. 1 and 2, the housing 10 has a bottom 13 along a height direction and two side 12 along a length direction; the battery cell 20 is placed in the shell 10, a third lug 24 is arranged on the battery cell 20, the third lug 24, a positive electrode lug 22 and a negative electrode lug 23 on the battery cell 20 are arranged on different sides of the battery cell 20, and the third lug 24 is connected with a negative electrode pole piece 212 of the battery cell 20; the third pole 30 is disposed on the bottom surface 13 or one of the side surfaces 12 of the housing 10, and is connected to the third pole 24.

Above-mentioned battery 100 for test sets up the third post 30 through on casing 10 to set up the third ear 24 on electric core 20, and the third ear 24 set up in with anodal utmost point ear 22 and negative pole utmost point ear 23 locate electric core 20 different sides, after accomplishing the connection of third ear 24 and third post 30, for example welded connection, can regard as the reference electrode, cooperate anodal post 15 and negative pole post 16 to test, thereby avoided setting up the reference electrode in apron 14, lead to destroying the condition of explosion-proof valve.

Referring to fig. 1 and 2, a square battery is taken as an example in the present embodiment. That is, the battery 100 for testing further includes a cover plate 14 in a conventional structure, the cover plate 14 is provided with a positive electrode post 15 and a negative electrode post 16, the positive electrode post 15 is connected with a positive electrode tab 22, the negative electrode post 16 is connected with a negative electrode tab 23, and the cover plate 14 is covered on the housing 10. The case 10 has a top end and a bottom surface 13 having openings in a height direction, and a cover plate 14 is provided to cover the top end of the case 10, then covers the openings, and then connects the top cover and the case 10, thereby realizing the installation of the conventional battery.

The housing 10 further includes two large surfaces 11 in the thickness direction, and the two side surfaces 12 in the length direction, and the bottom surface 13 is the surface opposite to the cover plate 14.

The battery in this embodiment is tested in a standing manner at the time of testing. Referring to fig. 1 and 2, in order to correspond to the placement posture of the battery during the test, the battery is convenient to stand during the test, the third pole 30 in the present embodiment is disposed on one of the side surfaces 12, i.e. one of the two side surfaces 12 of the housing 10, so that the bottom surface 13 can be in a flat state during the test, and the battery is convenient to stand vertically for the test. In other embodiments, the third pole 30 may also be disposed on the bottom surface 13 of the battery according to the testing conditions of the battery, for example, when the battery may be tested in a horizontally placed posture.

Referring to fig. 2 to 4, when the third pole 30 is disposed on one side 12 of the housing 10, the battery cell 20 is illustrated as being wound to form the battery cell 20, and the battery cell 20 includes a winding core 21, and a positive electrode tab 22 and a negative electrode tab 23 disposed on the winding core 21. Specifically, when the battery core 20 is manufactured, after the forming of the winding core 21 is completed, the positive electrode tab 22 and the negative electrode tab 23 are connected at one end of the winding core 21 in the width direction, for example, connected in a welding manner, the third electrode tab 24 is connected at the tail end of the winding core 21 in the winding direction, for example, connected in a welding manner, so that three tab arrangements on the winding core 21 are completed, the winding core 21 is placed in the housing 10, the positive electrode tab 22 is correspondingly connected with the Yu Zhengji column 15, the negative electrode tab 23 is connected with the negative electrode column 16, for example, connected in a welding manner, and the mounting hole 17 is provided at the side 12 of the housing 10, so that the third electrode tab 24 is connected with the third electrode column 30 through the mounting hole 17, for example, connected in a welding manner, so that the whole battery 100 for testing is manufactured.

Referring to fig. 5 and 6, when the third pole 30 is disposed on the bottom 13 of the casing 10, taking the winding core 21 as an example, after the winding core 21 is formed, one end of the winding core 21 in the width direction is connected with the positive pole tab 22 and the negative pole tab 23, for example, in a welded manner, one end of the winding core 21 in the width direction is connected with the third pole tab 24, for example, in a welded manner, so that the three pole tabs on the winding core 21 are disposed, the winding core 21 is disposed in the casing 10, the positive pole tab 22 is correspondingly connected with the Yu Zhengji pole 15, the negative pole tab 23 is connected with the negative pole 16, for example, in a welded manner, and the bottom 13 of the casing 10 is provided with the mounting hole 17, so that the third pole tab 24 is connected with the third pole through the mounting hole 17, for example, in a welded manner, so that the whole test battery 100 is prepared.

Therefore, when the third pole 30 is disposed on the side 12 or the bottom 13 of the housing 10, the third pole 24 is connected to the third pole 30 by welding, for example, laser welding, so as to improve the connection stability of the third pole 30 and the third pole 24.

It will be appreciated that when the third tab 24 is disposed within the winding core 21, the third tab 24 is connected to the negative pole piece 212 in the winding core 21.

Specifically, referring to fig. 7, the test battery 100 in the present embodiment is used to simulate the lithium precipitation of the battery under different fast-charge conditions, and when the battery is in a charged state, lithium ions on the positive electrode plate 213 are precipitated and run through the separator 211 to the negative electrode plate 212 to be combined with electrons. When the third tab 24 is connected to the negative electrode tab 212, since the winding core 21 includes the diaphragm 211, the negative electrode tab 212, the diaphragm 211 and the positive electrode tab 213, both surfaces of the negative electrode tab 212 are the diaphragm 211, when the battery is charged, in order to avoid the lithium from precipitating on the third tab 24 and affecting the test accuracy, the third tab 24 in this embodiment includes the first conductive area 241, the coating area 242 and the second conductive area 243, the first conductive area 241 is connected to the negative electrode tab 212, the surface of the coating area 242 is coated with the insulating material, and the second conductive area 243 is connected to the third tab 30, so that the first conductive area 241 without the insulating material is used to connect the negative electrode tab 212, the coating area 242 with the insulating material on the surface is used to extend the length of the entire third tab 24, and the second conductive area 243 without the insulating material is used to connect the third tab 30, thereby achieving the effect of insulating by the coating area 242 and avoiding the influence on the test result due to the lithium precipitation on the surface.

In this embodiment, the material of the third pole 30 is lithium, platinum or copper, specifically, in order to save cost and increase service life, in a specific embodiment, the material of the third pole 30 is copper, which is more resistant to use than lithium material, lithium is easy to oxidize and consume, and platinum is expensive, so that the third pole 30 in this embodiment is made of copper material.

The thickness of the third tab 24 in this embodiment is between 0.15mm and 0.25mm, so that a smaller thickness is required, and when the third tab 24 is welded to the negative electrode sheet 212, the winding core 21 generates a larger bulge at the position where the third tab 24 is welded, and meanwhile, the smaller thickness is adopted, so that the winding forming of the whole winding core 21 is not affected. For example, in some embodiments, the third ear 24 may be provided with a thickness of 0.15mm, 0.18mm, 0.20mm, 0.22mm, 0.25mm, and the like, without limitation.

The third tab 24 in this embodiment needs to be connected between the negative electrode pole 212 and the third electrode pole 30, and the length of the third tab 24 in this embodiment is between 1.8cm and 2.2cm, so that the third tab 24 and the negative electrode pole 212 can have a proper welding length, and can have a proper welding with the third electrode pole 30. For example, in some embodiments, the third ear 24 may be provided with a thickness of 1.8cm, 2.0cm, 2.2cm, etc., without limitation.

As can be seen from the above, in this embodiment, by disposing the third electrode lug 24 on the battery cell 20, disposing the third electrode post 30 on the housing 10, the third electrode lug 24 and the third electrode post 30 are welded to serve as reference electrodes, and the positive electrode post 15 and the negative electrode post 16 are matched to test the lithium precipitation condition of the battery cell 20 during quick charging when externally connecting with a testing device. In the test process, if Li+ removed from the positive electrode is not timely embedded into the negative electrode, a part of excess Li+ is reduced on the surface of the negative electrode, a reference electrode is introduced to monitor the actual potential of the negative electrode of the battery in the charging process, and if the minimum potential of the negative electrode reaches 0V or below, the lithium precipitation risk can be judged; meanwhile, the higher the SOC of the battery corresponding to the negative electrode reaching 0V, or the higher the lowest potential of the negative electrode, the better the material rate performance is indicated.

The technical means disclosed by the scheme of the utility model is not limited to the technical means disclosed by the embodiment, and also comprises the technical scheme formed by any combination of the technical features. It should be noted that modifications and adaptations to the utility model may occur to one skilled in the art without departing from the principles of the present utility model and are intended to be within the scope of the present utility model.

Claims

1. A battery for testing, comprising:

a housing having a bottom surface in a height direction and two side surfaces in a length direction;

the battery cell is arranged in the shell, a third lug is arranged on the battery cell, and the third lug, the positive electrode lug and the negative electrode lug on the battery cell are arranged on different sides of the battery cell;

the third pole is arranged on the bottom surface or one of the side surfaces and is connected with the third pole lug, the third pole lug comprises a first conductive area, a coating area and a second connection area, the first conductive area is connected with the negative pole piece, the coating area is coated with insulating materials, and the second connection area is connected with the third pole.

2. The battery of claim 1, wherein the third pole is disposed on one of the sides.

3. The battery for testing of claim 1, wherein the third tab and the third post are welded.

4. The battery according to claim 1, wherein the third electrode is made of lithium, platinum or copper.

5. The battery of claim 4, wherein the third pole is copper.

6. The battery according to claim 4 or 5, wherein the thickness of the third tab is between 0.15 and 0.25 mm.

7. The battery of claim 4 or 5, wherein the third tab has a length of between 1.8cm and 2.2 cm.