Laminated symmetrical battery assembly structure
By designing conductive components, damage to the membrane is avoided by wiping, and the electrochemical reaction area overlaps, the problem of inaccurate cell impedance testing in stacked symmetrical battery assembly is solved, improving testing accuracy and safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-17
- Publication Date
- 2026-03-24
AI Technical Summary
During the assembly of stacked symmetrical cells, wiping the membrane to remove active materials can cause irreversible damage, affecting the accuracy of cell impedance test results.
The device employs a conductive component design, including a first conductive sheet and a second conductive sheet. The tabs are welded onto the conductive sheets to avoid wiping the film, ensuring that the films are aligned and that the electrochemical reaction areas overlap. The device is then encapsulated in an aluminum-plastic film for testing.
It improves the accuracy of cell impedance test results for stacked symmetrical batteries, avoids membrane damage, and enhances the safety of battery assembly.
Smart Images
Figure CN224036595U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present disclosure relates to the field of electrochemical devices, in particular to a laminated symmetrical battery assembly structure. BACKGROUND
[0002] Symmetrical battery is an important means for evaluating material impedance, providing data support for rapid material system screening, and through obtaining positive or negative material impedance, providing support for analyzing the contribution proportion of positive and negative electrodes in the full battery. The symmetrical battery can be assembled separately for positive and negative electrodes for differentiation. The symmetrical battery is usually laminated or button type. The internal resistance of the laminated battery is smaller than that of the button battery, and the relative electrochemical analysis result is accurate.
[0003] However, the assembly of the laminated symmetrical battery is usually two identical membrane sheets, with a separator film in the middle, an electrolyte outside, and an aluminum plastic film packaging. The tabs are welded on the empty foil area of the membrane sheet. Before welding the tabs, it is necessary to ensure that there is an empty foil on the membrane sheet. However, when analyzing the local electrical performance of the battery, there is usually no empty foil on the membrane sheet. Therefore, it is necessary to wipe off the active material on the membrane sheet to expose the empty foil. The positive electrode membrane sheet usually uses NMP wiping to remove the active material, and the negative electrode membrane sheet usually uses deionized water to remove the active material. However, these substances will inevitably enter the membrane sheet during the wiping process, causing irreversible damage. For example, water can damage the SEI film on the negative electrode membrane sheet, and NMP can affect the discharge specific capacity and median voltage of the positive electrode membrane sheet, thereby reducing the cycle performance of the laminated symmetrical battery, and further leading to inaccurate battery impedance test results. CONTENT OF THE UTILITY MODEL
[0004] The purpose of the present disclosure is to overcome the deficiencies in the prior art and provide a laminated symmetrical battery assembly structure that does not require wiping of the membrane sheet while improving the accuracy of the battery impedance test results.
[0005] The purpose of the present disclosure is achieved by the following technical solutions:
[0006] A laminated symmetrical battery assembly structure is provided in an aluminum plastic film. The laminated symmetrical battery assembly structure includes a symmetrical battery body, the symmetrical battery body includes a first membrane sheet, a separator film and a second membrane sheet which are sequentially laminated, and the first membrane sheet is aligned with the second membrane sheet.
[0007] The laminated symmetrical battery assembly structure further includes a conductive assembly, the conductive assembly includes a first conductive sheet, a second conductive sheet, a first tab and a second tab, the first conductive sheet is attached to the second conductive sheet on the side of the first membrane sheet away from the separator film, the second conductive sheet is attached to the second membrane sheet on the side of the second membrane sheet away from the separator film, the first tab is welded on the first conductive sheet, the second tab is welded on the second conductive sheet, and the first tab and the second tab are located on the outside of the aluminum plastic film.
[0008] In one of the embodiments, the projection area of the first diaphragm overlaps with the projection area of the second diaphragm.
[0009] In one of the embodiments, the symmetrical cell body further comprises an insulating sheet, which is arranged between the first diaphragm and the isolation diaphragm, and the insulating sheet is provided with a hollow window.
[0010] In one of the embodiments, the projection area of the first conductive sheet is greater than or equal to the projection area of the first diaphragm.
[0011] The projection area of the second conductive sheet is greater than or equal to the projection area of the second diaphragm.
[0012] In one of the embodiments, the projection area of the isolation diaphragm is greater than the projection area of the hollow window.
[0013] In one of the embodiments, the projection area of the insulating sheet is greater than the projection area of the first conductive sheet.
[0014] The projection area of the insulating sheet is greater than the projection area of the second conductive sheet.
[0015] In one of the embodiments, the first diaphragm comprises a first foil layer, a first active substance layer and a second active substance layer, the first active substance layer is bonded to one side of the first foil layer, and the second active substance layer is bonded to the other side of the first foil layer.
[0016] In one of the embodiments, the second diaphragm comprises a second foil layer, a third active substance layer and a fourth active substance layer, the third active substance layer is bonded to one side of the second foil layer, and the fourth active substance layer is bonded to the other side of the second foil layer.
[0017] In one of the embodiments, the first conductive sheet is provided with a first tab mounting area, and the first tab is welded on the first tab mounting area.
[0018] In one of the embodiments, the second conductive sheet is provided with a second tab mounting area, and the second tab is welded on the second tab mounting area.
[0019] Compared with the prior art, the present disclosure has at least the following advantages:
[0020] By incorporating a first conductive sheet and a second conductive sheet, with the first tab positioned on the first conductive sheet and the second tab on the second conductive sheet, wiping the first and second films is unnecessary, thus avoiding irreversible damage to the first and second films caused by NMP and water. Furthermore, by aligning the first and second films, the electrochemical reaction areas of the first and second films overlap during cell impedance testing after the stacked symmetrical battery assembly structure is encapsulated in the aluminum-plastic film, thereby effectively improving the accuracy of cell impedance test results for the stacked symmetrical battery. Attached Figure Description
[0021] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this disclosure and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0022] Figure 1 This is a schematic diagram of the stacked symmetrical battery assembly structure after it is encapsulated in an aluminum-plastic film in one embodiment.
[0023] Figure 2 for Figure 1 A schematic diagram of the exploded structure of the stacked symmetrical battery assembly shown.
[0024] Figure 3 for Figure 1 A cross-sectional view of the stacked symmetrical battery assembly structure shown.
[0025] Figure 4 for Figure 2 A partial structural diagram of the stacked symmetrical battery assembly structure shown.
[0026] Figure 5 for Figure 2 A partial structural diagram of the stacked symmetrical battery assembly structure shown. Detailed Implementation
[0027] To facilitate understanding of this disclosure, a more complete description will be given below with reference to the accompanying drawings, which illustrate preferred embodiments of the present disclosure. However, this disclosure can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure.
[0028] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.
[0029] Unless otherwise defined, 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 disclosure belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0030] This disclosure provides a stacked symmetrical battery assembly structure disposed within an aluminum-plastic film. The stacked symmetrical battery assembly structure includes symmetrical battery cells, each comprising a first film, a separator film, and a second film stacked sequentially, with the first film and the second film aligned. The stacked symmetrical battery assembly structure further includes a conductive component, comprising a first conductive sheet, a second conductive sheet, a first tab, and a second tab. The first conductive sheet is bonded to the side of the first film opposite to the separator film, and the second conductive sheet is bonded to the side of the second film opposite to the separator film. The first tab is welded to the first conductive sheet, and the second tab is welded to the second conductive sheet. Both the first tab and the second tab are located on the outer side of the aluminum-plastic film.
[0031] Please see Figures 1 to 3 To better understand the stacked symmetrical battery assembly structure 10 of this disclosure, the following further explanation of the stacked symmetrical battery assembly structure 10 is provided:
[0032] The laminated symmetrical battery assembly structure 10 of one embodiment is arranged in the aluminum plastic film 20, and the laminated symmetrical battery assembly structure 10 comprises a symmetrical battery core body 100, the symmetrical battery core body 100 comprises a first film piece 110, a separation film piece 120 and a second film piece 130 which are sequentially laminated, and the first film piece 110 is arranged in alignment with the second film piece 130. The laminated symmetrical battery assembly structure 10 further comprises a conductive assembly 200, the conductive assembly 200 comprises a first conductive piece 210, a second conductive piece 220, a first tab 230 and a second tab 240, the first conductive piece 210 is attached to the second conductive piece 220 on the side of the first film piece 110 and the second film piece 130 away from the separation film piece 120, the first tab 230 is welded on the first conductive piece 210, the second tab 240 is welded on the second conductive piece 220, and the first tab 230 and the second tab 240 are both located outside the aluminum plastic film 20.
[0033] In the embodiment, by arranging the first conductive piece 210 and the second conductive piece 220, and arranging the first tab 230 on the first conductive piece 210 and the second tab 240 on the second conductive piece 220, the first film piece 110 and the second film piece 130 do not need to be wiped, so that the irreversible damage of the first film piece 110 and the second film piece 130 caused by NMP and water is avoided, and the electrochemical reaction area of the first film piece 110 and the second film piece 130 is overlapped when the laminated symmetrical battery assembly structure 10 is encapsulated in the aluminum plastic film 20 and the battery core impedance test is performed, so that the accuracy of the battery core impedance test result of the laminated symmetrical battery is effectively improved.
[0034] It should be noted that the first film piece 110 and the second film piece 130 are both positive film pieces or negative film pieces, and can be any region of the battery core film for analyzing abnormal regions of the battery core.
[0035] It should be noted that the first conductive piece 210 and the second conductive piece 220 are metal copper pieces or metal aluminum pieces
[0036] For example, Figure 2 and Figure 3As shown in the drawings, in one of the embodiments, the projection area of the first diaphragm 110 overlaps with the projection area of the second diaphragm 130. It can be understood that the projection area of the first diaphragm 110 overlaps with the projection area of the second diaphragm 130, that is, the size of the first diaphragm 110 overlaps with the size of the second diaphragm 130, and by aligning the first diaphragm 110 and the second diaphragm 130, the electrochemical reaction area of the first diaphragm 110 and the second diaphragm 130 is overlapped, so as to improve the accuracy of the impedance test results of the first diaphragm 110 and the second diaphragm 130, and further improve the accuracy of the impedance test results of the cell of the laminated symmetrical battery.
[0037] As shown in the drawings, Figure 2 and Figure 3 As shown in the drawings, in one of the embodiments, the symmetrical battery cell body 100 further comprises an insulating sheet 140, which is arranged between the first diaphragm 110 and the isolation diaphragm 120, and the insulating sheet 140 is provided with a hollow window 1402. It should be noted that since the laminated symmetrical battery is assembled in a laminated manner, the first diaphragm 110 and the second diaphragm 130 are prone to deviation when the laminated stack is assembled into a battery package structure and the aluminum plastic film 20 is encapsulated, thereby causing the accuracy of the cell impedance test results to decrease. Therefore, in the present embodiment, the insulating sheet 140 is arranged between the first diaphragm 110 and the isolation diaphragm 120, and the hollow window 1402 is provided on the insulating sheet 140, so that the ions can only pass through the hollow window 1402, that is, the area of the hollow window 1402 is controlled to control the effective reaction area corresponding to the first diaphragm 110 and the second diaphragm 130, so as to ensure that the effective reaction area of the first diaphragm 110 and the second diaphragm 130 is overlapped, thereby improving the accuracy of the cell impedance test results of the laminated symmetrical battery.
[0038] As shown in the drawings, Figure 2 and Figure 3 As shown in the drawings, in one of the embodiments, the projection area of the first conductive sheet 210 is greater than or equal to the projection area of the first diaphragm 110. The projection area of the second conductive sheet 220 is greater than or equal to the projection area of the second diaphragm 130. It can be understood that the projection area of the first conductive sheet 210 is greater than or equal to the projection area of the first diaphragm 110, so that the conductive surface can cover the first diaphragm 110. Similarly, the projection area of the second conductive sheet 220 is greater than or equal to the projection area of the second diaphragm 130, so that the conductive surface can cover the second diaphragm 130. Further, by externally connecting the first conductive sheet 210 and the second conductive sheet 220, an electrochemical reaction occurs on the first diaphragm 110 and the second diaphragm 130, so as to perform impedance test on the first diaphragm 110 and the second diaphragm 130.
[0039] As shown in the drawings, Figure 2 and Figure 3As shown in the drawings, in one embodiment, the projection area of the isolation diaphragm 120 is greater than the projection area of the hollow window 1402. It can be understood that the projection area of the isolation diaphragm 120 is greater than the projection area of the hollow window 1402, which can avoid the short circuit caused by the contact between the first diaphragm 110 and the second diaphragm 130, and improve the safety of the laminated symmetrical battery assembly structure 10.
[0040] As shown in the drawings, Figure 2 and Figure 3 As shown in the drawings, in one embodiment, the projection area of the insulation sheet 140 is greater than the projection area of the first conductive sheet 210. The projection area of the insulation sheet 140 is greater than the projection area of the second conductive sheet 220. It can be understood that the projection area of the insulation sheet 140 is greater than the projection area of the first conductive sheet 210 and the projection area of the second conductive sheet 220, respectively, and because the projection area of the first conductive sheet 210 is greater than or equal to the projection area of the first diaphragm 110, and the projection area of the second conductive sheet 220 is greater than or equal to the projection area of the second diaphragm 130, the projection area of the insulation sheet 140 is greater than the projection area of the first conductive sheet 210, the first diaphragm 110, the second conductive sheet 220 and the second diaphragm 130, respectively, thereby avoiding the short circuit caused by the contact between the first diaphragm 110 and the second diaphragm 130, and further improving the safety of the laminated symmetrical battery assembly structure 10.
[0041] As shown in the drawings, Figure 3 As shown in the drawings, in one embodiment, the first diaphragm 110 includes a first foil layer 1110, a first active material layer 1120 and a second active material layer 1130, the first active material layer 1120 is bonded to one side of the first foil layer 1110, and the second active material layer 1130 is bonded to the other side of the first foil layer 1110. It can be understood that since the first diaphragm 110 is detached from any area of the positive or negative pole piece of the battery cell, regardless of the positive or negative pole, both sides of the first foil layer 1110 are coated with the first active material layer 1120 and the second active material layer 1130.
[0042] As shown in the drawings, Figure 3 As shown in the drawings, in one embodiment, the second diaphragm 130 includes a second foil layer 1310, a third active material layer 1320 and a fourth active material layer 1330, the third active material layer 1320 is bonded to one side of the second foil layer 1310, and the fourth active material layer 1330 is bonded to the other side of the second foil layer 1310. It can be understood that since the second diaphragm 130 is detached from any area of the positive or negative pole piece of the battery cell, regardless of the positive or negative pole, both sides of the second foil layer 1310 are coated with the third active material layer 1320 and the fourth active material layer 1330.
[0043] As Figure 1 , Figure 2 and Figure 4 shown, in one embodiment, the first conductive sheet 210 is provided with a first tab mounting area 2102, and the first tab 230 is welded on the first tab mounting area 2102. It should be noted that by leaving the first tab mounting area 2102 on the first conductive sheet 210, the first tab 230 is welded on the first conductive sheet 210, and the first diaphragm 110 is electrically connected to the external circuit through the first tab 230 and the first conductive sheet 210, without the need for additional wiping of the first diaphragm 110, improving the accuracy of the cell impedance test results of the stacked symmetrical battery.
[0044] As Figure 1 , Figure 2 and Figure 5 shown, in one embodiment, the second conductive sheet 220 is provided with a second tab mounting area 2202, and the second tab 240 is welded on the second tab mounting area 2202. It should be noted that by leaving the second tab mounting area 2202 on the second conductive sheet 220, the second tab 240 is welded on the second conductive sheet 220, and the second diaphragm 130 is electrically connected to the external circuit through the second tab 240 and the second conductive sheet 220, without the need for additional wiping of the second diaphragm 130, improving the accuracy of the cell impedance test results.
[0045] Compared with the prior art, the present disclosure has at least the following advantages:
[0046] By providing a first conductive sheet and a second conductive sheet, and arranging the first tab on the first conductive sheet and the second tab on the second conductive sheet, wiping of the first diaphragm and the second diaphragm is not required, avoiding the irreversible damage to the first diaphragm and the second diaphragm caused by NMP and water, and by aligning the first diaphragm and the second diaphragm, the electrochemical reaction area of the first diaphragm and the second diaphragm overlaps when the stacked symmetrical battery assembly structure is encapsulated in the aluminum-plastic film and subjected to cell impedance testing, thereby effectively improving the accuracy of the cell impedance test results of the stacked symmetrical battery.
[0047] The above-described embodiments only express several embodiments of the present disclosure, which are described in detail and specifically, but should not be construed as limiting the scope of the disclosed patent. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present disclosure, a number of modifications and improvements can be made, which are within the scope of the present disclosure. Therefore, the protection scope of the present disclosure patent should be subject to the appended claims.
Claims
1. A stacked symmetrical battery assembly structure provided in an aluminum-plastic film, the stacked symmetrical battery assembly structure comprising a symmetrical cell body, the symmetrical cell body comprising a first film sheet, a separator film sheet, and a second film sheet sequentially laminated, the first film sheet and the second film sheet being provided in alignment, characterized in that, The conductive assembly also includes a first conductive sheet and a second conductive sheet. The conductive assembly includes a first conductive sheet, a second conductive sheet, a first tab and a second tab, the first conductive sheet is attached to one side of the second conductive sheet away from the isolation film, the first tab is welded on the first conductive sheet, the second tab is welded on the second conductive sheet, and the first tab and the second tab are both located outside the aluminum plastic film.
2. The laminated symmetric battery assembly structure according to claim 1, wherein The projection area of the first film sheet overlaps the projection area of the second film sheet.
3. The structure of claim 1, wherein The symmetrical battery body also includes an insulating sheet, the insulating sheet is arranged between the first film sheet and the isolation film, and the insulating sheet is provided with a hollow window.
4. The structure of claim 1, wherein The projection area of the first conductive sheet is greater than or equal to the projection area of the first film sheet. The projection area of the second conductive sheet is greater than or equal to the projection area of the second film sheet.
5. The structure of claim 3, wherein The projection area of the isolation film is greater than the projection area of the hollow window.
6. The structure of claim 3, wherein The projection area of the insulating sheet is greater than the projection area of the first conductive sheet. The projection area of the insulating sheet is greater than the projection area of the second conductive sheet.
7. The structure of claim 1, wherein The first film sheet includes a first foil layer, a first active material layer and a second active material layer, the first active material layer is attached to one side of the first foil layer, and the second active material layer is attached to the other side of the first foil layer.
8. The structure of claim 1, wherein The second film sheet includes a second foil layer, a third active material layer and a fourth active material layer, the third active material layer is attached to one side of the second foil layer, and the fourth active material layer is attached to the other side of the second foil layer.
9. The structure of claim 1, wherein The first conductive sheet is provided with a first tab mounting area, and the first tab is welded on the first tab mounting area.
10. The structure of claim 1, wherein The second conductive sheet is provided with a second tab mounting area, and the second tab is welded on the second tab mounting area.