Battery cell
By setting a positive electrode at the top and/or bottom of the lithium-ion battery stack and placing a reference electrode on the outer surface of the positive electrode, the problem of rapid capacity loss of the negative electrode is solved, stable potential monitoring of the lithium-ion battery is achieved, and lithium plating and safety hazards are avoided.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-17
- Publication Date
- 2026-03-31
AI Technical Summary
During the charging and discharging process of lithium-ion batteries, the capacity loss rate of the negative electrode is higher than that of the positive electrode, which leads to the precipitation of lithium ions and may cause safety issues. In addition, the existing reference electrode has low stability and cannot effectively monitor changes in battery potential.
The top and/or bottom electrodes of the stack are set as positive electrodes, and the reference electrode is placed on the outer surface of the positive electrode to avoid the loss of lithium ions in the middle region of the positive electrode by the reference electrode, thereby achieving stable monitoring of the positive and negative electrode potentials.
It effectively avoids negative electrode capacity loss, stably monitors potential changes during lithium battery charging and discharging, and prevents lithium plating and other safety issues.
Smart Images
Figure CN224067686U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to battery structure technical field, specifically, relate to a kind of electric core. BACKGROUND
[0002] With the increasing of lithium ion battery charge-discharge times, the positive and negative electrode materials will have different degrees of capacity loss, wherein if the capacity loss rate of negative electrode is higher than that of positive electrode, lithium ion may be deposited and precipitated differently in negative electrode, commonly known as lithium precipitation. The occurrence of lithium precipitation phenomenon may eventually cause internal short circuit of lithium battery, thereby triggering battery safety problems. In order to avoid the occurrence of such phenomenon, the current common method is to introduce reference electrode to monitor the potential of positive and negative electrodes. When the lithium potential of negative electrode is higher than 0V, lithium precipitation phenomenon will not occur. However, the current reference electrode still has the problems of low stability and loss of part of battery active lithium.
[0003] Therefore, the utility model is provided. UTILITY MODEL CONTENT
[0004] The utility model aims to provide an electric core to solve or improve the above technical problems.
[0005] The utility model can be realized as follows:
[0006] In a first aspect, the utility model provides an electric core, which includes a laminated body and a reference electrode;
[0007] The laminated body is obtained by interleaving and stacking positive and negative electrode sheets, and the electrode sheet at the top and / or bottom of the laminated body is a positive electrode sheet;
[0008] The reference electrode is arranged on the outer surface of the outermost positive electrode sheet of the laminated body.
[0009] In an optional embodiment, the electrode sheet at the top of the laminated body is a positive electrode sheet, and the electrode sheet at the bottom of the laminated body is a negative electrode sheet;
[0010] The reference electrode is arranged on the upper surface of the electrode sheet at the top of the laminated body.
[0011] In an optional embodiment, the electrode sheet at the top of the laminated body is a negative electrode sheet, and the electrode sheet at the bottom of the laminated body is a positive electrode sheet;
[0012] The reference electrode is arranged on the lower surface of the electrode sheet at the bottom of the laminated body.
[0013] In an optional embodiment, the electrode sheet at the top and the electrode sheet at the bottom of the laminated body are both positive electrode sheets;
[0014] The reference electrode is arranged on the upper surface of the electrode sheet at the top and / or the lower surface of the electrode sheet at the bottom.
[0015] In an optional embodiment, the reference electrode comprises a reference tab and a tab jelly, the tab jelly separates the reference tab into a first tab area and a second tab area, wherein the first tab area and the tab jelly do not overlap with the stack body, and the surface of the second tab area is provided with a diaphragm and the second tab area at least partially overlaps with the stack body.
[0016] In an optional embodiment, the number of reference electrodes is multiple, and the multiple reference electrodes are arranged at different positions on the outer surface of the same positive electrode tab.
[0017] In an optional embodiment, each positive electrode tab is provided with one positive electrode tab.
[0018] In an optional embodiment, each negative electrode tab is provided with one negative electrode tab.
[0019] In an optional embodiment, the battery cell further comprises a first external tab and a second external tab.
[0020] All the positive electrode tabs are connected to the first external tab at the same time, and all the negative electrode tabs are connected to the second external tab at the same time.
[0021] In an optional embodiment, the number of positive electrode tabs is 1-40.
[0022] The beneficial effects of the present application include:
[0023] In the present application, the top and / or bottom tabs of the stack body are set as positive electrode tabs, and the reference electrode is arranged on the outer surface of the positive electrode tab, so that the loss of lithium ions contained in the positive electrode tabs in the middle region of the stack body during use can be avoided, and the capacity loss can be avoided. In other words, the battery cell provided by the present application can stably monitor the positive and negative potential changes of the lithium battery during the charge and discharge cycle, avoid the capacity loss rate of the negative electrode being higher than that of the positive electrode, and thus avoid the occurrence of lithium precipitation and other safety problems. BRIEF DESCRIPTION OF DRAWINGS
[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.
[0025] Figure 1 The first stacking diagram of the positive electrode tab and the negative electrode tab in the battery cell provided by the present application;
[0026] Figure 2 The second stacking diagram of the positive electrode tab and the negative electrode tab in the battery cell provided by the present application;
[0027] Figure 3 This is a schematic diagram of a third type of stacking of the positive and negative electrode plates in the battery cell provided in this embodiment;
[0028] Figure 4 This is a schematic diagram of the structure of the reference electrode in the battery cell provided in this embodiment before the separator is installed;
[0029] Figure 5 This is a schematic diagram of the structure of the reference electrode in the battery cell after the diaphragm is installed, as provided in this embodiment.
[0030] Figure 6 This is a diagram showing the first possible placement of the reference electrode in the battery cell provided in this embodiment;
[0031] Figure 7 This is a diagram showing a second possible placement of the reference electrode in the battery cell provided in this embodiment;
[0032] Figure 8 This is a diagram showing the third possible placement of the reference electrode in the battery cell provided in this embodiment;
[0033] Figure 9 This is a diagram showing the fourth possible placement of the reference electrode in the battery cell provided in this embodiment;
[0034] Figure 10 This is a schematic diagram of the three-electrode stack in Application Example 1 from a first-view perspective;
[0035] Figure 11 This is a schematic diagram of the three-electrode stack in Application Example 1 from a second perspective.
[0036] Figure 12 This is a graph showing the potential change of the negative electrode during charge-discharge cycles in Application Example 1.
[0037] Figure 13 This is a schematic diagram of the three-electrode stack in Application Example 2 from a first-view perspective;
[0038] Figure 14 This is a schematic diagram of the three-electrode stack in Application Example 2 from a second perspective.
[0039] Figure 15 This is a graph showing the potential change of the negative electrode during charge-discharge cycles in Application Example 2.
[0040] Figure 16 This is a schematic diagram of the three-electrode stack in Comparative Example 1 from a first-view perspective;
[0041] Figure 17 This is a schematic diagram of the three-electrode stack in Comparative Example 1 from a second perspective.
[0042] Figure 18The graph shows the potential change of the negative electrode during charge-discharge cycles in Comparative Example 1.
[0043] Icons: 11-Positive electrode; 12-Positive electrode tab; 21-Negative electrode; 22-Negative electrode tab; 30-Reference electrode; 31-Reference electrode; 311-First electrode region; 312-Second electrode region; 32-Electrode tab adhesive; 33-Separator; 41-Positive electrode tab of laminated body; 42-Negative electrode tab of laminated body. Detailed Implementation
[0044] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0045] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
[0046] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0047] In the description of this utility model, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the utility model product is usually placed during use, they are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.
[0048] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.
[0049] It should be noted that, where there is no conflict, the features in the embodiments of this utility model can be combined with each other.
[0050] Example
[0051] This utility model provides a battery cell, which includes a stacked body and a reference electrode 30;
[0052] Please refer to the above as well. Figures 1 to 3 The laminate is formed by alternating positive electrode 11 and negative electrode 21, and the electrode at the top and / or bottom of the laminate is the positive electrode 11;
[0053] The reference electrode 30 is disposed on the outer surface of the outermost positive electrode 11 of the stack.
[0054] It should be noted that the stacking sequence of conventional electrode stacks is usually "negative-positive-negative...negative-positive-negative", meaning that the top and bottom electrodes of the stack are both negative electrodes 21. This stack configuration restricts the reference electrode 30 to the middle region of the stack. When the reference electrode 30 is placed in the middle region, it will lose lithium ions contained in the positive electrode 11 during use, resulting in capacity loss. Furthermore, as the number of battery charge-discharge cycles increases, the capacity loss rate of the negative electrode will be higher than that of the positive electrode, leading to lithium ion deposition at the negative electrode. This makes it impossible to stably detect voltage changes between the positive and negative electrodes during long-term battery charge-discharge cycles.
[0055] In this embodiment, by setting the top and / or bottom electrodes of the stack as positive electrodes 11 and placing the reference electrode 30 on the outer surface of the positive electrode 11, it is possible to avoid the loss of lithium ions contained in the positive electrode 11 in the middle region of the stack by the reference electrode 30 during use, which would lead to capacity loss. In other words, the cell provided in this embodiment can stably monitor the changes in the positive and negative electrode potentials of the lithium battery during the charge and discharge cycle, and avoid the capacity loss rate of the negative electrode being higher than that of the positive electrode, thereby avoiding the occurrence of lithium plating and other safety problems.
[0056] In some optional embodiments, the number of positive electrode sheets 11 in this embodiment can be from 1 to 40, such as 1, 2, 5, 10, 15, 20, 25, 30, 35, or 40 sheets, or other values within the range of 1 to 40 sheets. In some other embodiments, the number of positive electrode sheets 11 can be set to more than 40 sheets according to actual needs. The number of negative electrode sheets 21 is set according to different stacking methods.
[0057] In some alternative embodiments, the electrode at the top of the stack is called the "top electrode," and the electrode at the bottom of the stack is called the "bottom electrode." The top electrode is the positive electrode 11, and the bottom electrode is the negative electrode 21 (in other words, the stacking order from bottom to top is "negative-positive-negative...positive-negative-positive"), as shown below. Figure 1 (as shown);
[0058] The reference electrode 30 is disposed on the upper surface of the top electrode.
[0059] In some alternative embodiments, the electrode at the top of the stack is called the "top electrode" and the electrode at the bottom of the stack is called the "bottom electrode," wherein the top electrode is the negative electrode 21 and the bottom electrode is the positive electrode 11 (in other words, the stacking order from bottom to top is "positive-negative-positive...positive-negative"), as shown below. Figure 2 (as shown);
[0060] The reference electrode 30 is disposed on the lower surface of the bottom electrode.
[0061] In some alternative embodiments, the electrode at the top of the stack is called the "top electrode" and the electrode at the bottom of the stack is called the "bottom electrode," wherein both the top and bottom electrodes are positive electrodes 11 (in other words, the stacking order from bottom to top is "positive-negative-positive...positive-negative-positive"), such as... Figure 3 (as shown);
[0062] The reference electrode 30 is disposed on the upper surface of the top electrode and / or the lower surface of the bottom electrode. In other words, when both the top electrode and the bottom electrode are positive electrodes 11, the reference electrode 30 may be disposed only on the upper surface of the top electrode or the lower surface of the bottom electrode, or the reference electrode 30 may be disposed on both the upper surface of the top electrode and the lower surface of the bottom electrode.
[0063] In this embodiment, please refer to Figure 4 and Figure 5 The reference electrode 30 includes a reference electrode 31 and a tab adhesive 32. The tab adhesive 32 separates the reference electrode 31 into a first electrode region 311 and a second electrode region 312. The first electrode region 311 and the tab adhesive 32 do not overlap with the stacked body. The surface of the second electrode region 312 is provided with a diaphragm 33 and the second electrode region 312 overlaps with the stacked body at least partially.
[0064] The number of layers of the aforementioned diaphragm 33 can be set to 1, 2, 3 or more layers according to actual needs.
[0065] In this embodiment, the number of reference electrodes 30 can be only one or more, such as two, three or more. When there are multiple reference electrodes 30, the multiple reference electrodes 30 are disposed at different positions on the outer surface of the same positive electrode 11.
[0066] In this embodiment, each positive electrode 11 is provided with one positive electrode tab 12. Each negative electrode 21 is provided with one negative electrode tab 22. All the positive electrode tabs 12 together form a stacked positive electrode tab 41, and all the negative electrode tabs 22 together form a stacked negative electrode tab 42.
[0067] For example, the reference electrode 30 may be disposed on the same side of the positive tab 41 or the negative tab 42 of the laminate (e.g.,Figure 6 (As shown), it can also be located on the opposite side of the positive tab 41 or the negative tab 42 of the laminate (e.g. Figure 7 As shown), it can also be located on the left side of the positive tab 41 or the negative tab 42 of the laminate (as shown). Figure 8 (as shown) or on the right (as shown) Figure 9 (As shown).
[0068] In this embodiment, the battery cell also includes a first external electrode and a second external electrode;
[0069] All positive electrode tabs 12 are simultaneously connected to the first external electrode tab, and all negative electrode tabs 22 are simultaneously connected to the second external electrode tab.
[0070] Specifically, all the positive electrode tabs 12 together form a stacked positive electrode tab 41 to connect with the first external electrode tab, and all the negative electrode tabs 22 together form a stacked negative electrode tab 42 to connect with the second external electrode tab.
[0071] Furthermore, the cell also includes an electrolyte, which is used to form ion channels, thereby ensuring that there are enough lithium ions migrating between the positive electrode 11 and the negative electrode 21 during the charging and discharging process, so as to achieve reversible cycling.
[0072] In some implementations, the battery cell can be manufactured in the following manner:
[0073] S1: Follow the traditional lithium battery manufacturing method to carry out processes such as positive and negative electrode homogenization, coating, rolling, and die cutting.
[0074] S2: The die-cut positive electrode sheet 11 with positive electrode tab 12 and negative electrode sheet 21 with negative electrode tab 22 are stacked to obtain a stacked body. At least one of the bottom electrode sheet and the top electrode sheet of the stacked body is a positive electrode sheet 11.
[0075] S3: Take a copper tab and wrap it with a diaphragm 33 one or two times (one or two layers of diaphragm 33 are set outside the copper tab) so that the copper below the tab adhesive 32 is completely wrapped in the middle of the diaphragm 33, thus obtaining the reference electrode 30.
[0076] S4: Place the reference electrode 30 on the outside of the positive electrode 11 at the top or bottom of the stack body, wherein the tab adhesive 32 part does not overlap with the stack body. The reference electrode 30 can be set on the same side of the positive electrode tab 12 or the negative electrode tab 22 in the stack body, or on the opposite side of the positive electrode tab 12 or the negative electrode tab 22 in the stack body, or on the left or right side of the positive electrode tab 12 or the negative electrode tab 22 in the stack body, to obtain a three-electrode stack body;
[0077] S5: The three-electrode stack is welded, packaged, injected with electrolyte, and impregnated according to the traditional lithium battery manufacturing method to obtain a three-electrode cell.
[0078] As an example, the activation process of the reference electrode 30 in the above-mentioned three-electrode cell can be referred to as follows: in the battery charger, connect the positive electrode of the three-electrode cell to the positive electrode of the charger, connect the reference electrode 30 of the three-electrode cell to the negative electrode of the charger, and charge with a charging current of 20μA to 500μA for 1h to 20h.
[0079] Furthermore, after the activated three-electrode cell is subjected to normal charge-discharge cycles, the positive terminal of the charge-discharge machine is connected to the positive terminal of the cell, the negative terminal of the charge-discharge machine is connected to the negative terminal of the cell, and the auxiliary channel of the charge-discharge machine is connected to the reference electrode 30, so that the potential change of the negative terminal during the charge-discharge cycle can be monitored synchronously.
[0080] Application Example 1
[0081] S1: Lithium nickel cobalt manganese oxide, conductive agent SP, and binder PVDF are added in a mass ratio of 96:2:2 to perform positive electrode slurry homogenization, coating, rolling, and die cutting to obtain a positive electrode sheet 11 with positive electrode tab 12; silicon carbide, conductive agent CNT, binder CMC, and binder PAA are added in a mass ratio of 96:2:1:1 to perform negative electrode slurry homogenization, coating, rolling, and die cutting to obtain a negative electrode sheet 21 with negative electrode tab 22.
[0082] S2: Stack the above 5 positive electrode plates 11 and 4 negative electrode plates 21 in the manner of "positive-negative-positive-negative-positive-negative-positive-negative-positive" to obtain a stacked body (positive electrode tab 12 and negative electrode tab 22 are located on the same side).
[0083] S3: Take a copper tab and wrap it twice with the diaphragm 33 so that the copper below the tab adhesive 32 is completely wrapped in the middle of the diaphragm 33, thus obtaining the reference electrode 30.
[0084] S4: Place the reference electrode 30 on top of the stack and on the opposite side of the positive electrode tab 12 and the negative electrode tab 22 to obtain a three-electrode stack (e.g., Figure 10 and Figure 11 (As shown).
[0085] S5: The three-electrode stack is welded, packaged, injected with electrolyte, and impregnated according to the traditional lithium battery manufacturing method to obtain a three-electrode cell.
[0086] S6: Activate the reference electrode 30 of the three-electrode cell. The activation process is as follows: Connect the positive electrode of the three-electrode cell to the positive electrode of the charge / discharge machine in the battery charge / discharge machine, connect the reference electrode 30 of the three-electrode cell to the negative electrode of the charge / discharge machine, and charge with a charging current of 50μA for 10 hours.
[0087] The activated three-electrode cell was subjected to normal charge-discharge cycles. The positive terminal of the charge-discharge machine was connected to the positive terminal of the cell, and the negative terminal of the charge-discharge machine was connected to the negative terminal of the cell. The auxiliary channel of the charge-discharge machine was connected to the reference electrode 30. The potential change of the negative terminal during the charge-discharge cycles was monitored synchronously. The results are as follows: Figure 12 As shown.
[0088] Application Example 2
[0089] S1: Lithium nickel cobalt manganese oxide, conductive agent SP, and binder PVDF are added in a mass ratio of 96:2:2 to perform positive electrode slurry homogenization, coating, rolling, and die cutting to obtain a positive electrode sheet 11 with positive electrode tab 12; silicon carbide, conductive agent CNT, binder CMC, and binder PAA are added in a mass ratio of 96:2:1:1 to perform negative electrode slurry homogenization, coating, rolling, and die cutting to obtain a negative electrode sheet 21 with negative electrode tab 22.
[0090] S2: Stack the above 4 positive electrode plates 11 and 4 negative electrode plates 21 in the manner of "positive-negative-positive-negative-positive-negative-positive-negative" to obtain a stacked body (positive electrode tab 12 and negative electrode tab 22 are located on the same side).
[0091] S3: Take a copper tab and wrap it twice with the diaphragm 33 so that the copper below the tab adhesive 32 is completely wrapped in the middle of the diaphragm 33, thus obtaining the reference electrode 30.
[0092] S4: Place the reference electrode 30 at the bottom of the stack and to the right of the positive electrode tab 12 and the negative electrode tab 22 to obtain a three-electrode stack (e.g., Figure 13 and Figure 14 (As shown).
[0093] S5: The three-electrode stack is welded, packaged, injected with electrolyte, and impregnated according to the traditional lithium battery manufacturing method to obtain a three-electrode cell.
[0094] S6: Activate the reference electrode 30 of the three-electrode cell. The activation process is as follows: Connect the positive electrode of the three-electrode cell to the positive electrode of the charge / discharge machine in the battery charge / discharge machine, connect the reference electrode 30 of the three-electrode cell to the negative electrode of the charge / discharge machine, and charge with a charging current of 100μA for 5 hours.
[0095] The activated three-electrode cell was subjected to normal charge-discharge cycles. The positive terminal of the charge-discharge machine was connected to the positive terminal of the cell, and the negative terminal of the charge-discharge machine was connected to the negative terminal of the cell. The auxiliary channel of the charge-discharge machine was connected to the reference electrode 30. The potential change of the negative terminal during the charge-discharge cycles was monitored synchronously. The results are as follows: Figure 15 As shown.
[0096] Comparative Example 1
[0097] S1: Lithium nickel cobalt manganese oxide, conductive agent SP, and binder PVDF are added in a mass ratio of 96:2:2 to perform positive electrode slurry homogenization, coating, rolling, and die cutting to obtain a positive electrode sheet 11 with positive electrode tab 12; silicon carbide, conductive agent CNT, binder CMC, and binder PAA are added in a mass ratio of 96:2:1:1 to perform negative electrode slurry homogenization, coating, rolling, and die cutting to obtain a negative electrode sheet 21 with negative electrode tab 22.
[0098] S2: Stack the above 4 positive electrode plates 11 and 5 negative electrode plates 21 in the manner of "negative-positive-negative-positive-negative-positive-negative" to obtain a stacked body (positive electrode tab 12 and negative electrode tab 22 are located on the same side).
[0099] S3: Take a copper tab and wrap it twice with the diaphragm 33 so that the copper below the tab adhesive 32 is completely wrapped in the middle of the diaphragm 33, thus obtaining the reference electrode 30.
[0100] S4: Place the reference electrode 30 inside the stacked body (from top to bottom, specifically between the second positive electrode 11 and the third negative electrode 21) and on the opposite side of the positive electrode tab 12 and the negative electrode tab 22 to obtain a three-electrode stacked body (e.g., Figure 16 and Figure 17 (As shown).
[0101] S5: The three-electrode stack is welded, packaged, injected with electrolyte, and impregnated according to the traditional lithium battery manufacturing method to obtain a three-electrode cell.
[0102] S6: Activate the reference electrode 30 of the three-electrode cell. The activation process is as follows: Connect the positive electrode of the three-electrode cell to the positive electrode of the charge / discharge machine in the battery charge / discharge machine, connect the reference electrode 30 of the three-electrode cell to the negative electrode of the charge / discharge machine, and charge with a charging current of 200μA for 5 hours.
[0103] The activated three-electrode cell was subjected to normal charge-discharge cycles. The positive terminal of the charge-discharge machine was connected to the positive terminal of the cell, and the negative terminal of the charge-discharge machine was connected to the negative terminal of the cell. The auxiliary channel of the charge-discharge machine was connected to the reference electrode 30. The potential change of the negative terminal during the charge-discharge cycles was monitored synchronously. The results are as follows: Figure 18 As shown.
[0104] Depend on Figure 12 , Figure 15 , Figure 18 The comparison shows that the reference electrode 30 prepared in Comparative Example 1 has poor stability during battery cycling, and its voltage decays rapidly, making it impossible to accurately detect the actual voltage of the negative electrode in the corresponding battery.
[0105] The above description is only a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model.
Claims
1. An electric cell, characterized by, The electrode assembly comprises a stack body and a reference electrode; The stack body is formed by interleaving positive electrode plates and negative electrode plates, and the top and / or bottom electrode plates of the stack body are positive electrode plates; The reference electrode is arranged on the outer surface of the outermost positive electrode plate of the stack body.
2. The electric cell of claim 1, wherein, The top electrode plate of the stack body is a positive electrode plate, and the bottom electrode plate of the stack body is a negative electrode plate; The reference electrode is arranged on the upper surface of the top electrode plate of the stack body.
3. The electric cell of claim 1, wherein, The top electrode plate of the stack body is a negative electrode plate, and the bottom electrode plate of the stack body is a positive electrode plate; The reference electrode is arranged on the lower surface of the bottom electrode plate of the stack body.
4. The electric cell of claim 1, wherein, The top and bottom electrode plates of the stack body are positive electrode plates; The reference electrode is arranged on the upper surface of the top electrode plate and / or the lower surface of the bottom electrode plate.
5. The battery cell of any one of claims 1 to 4, wherein, The reference electrode comprises a reference electrode plate and a tab adhesive, and the tab adhesive separates the reference electrode plate into a first electrode plate area and a second electrode plate area, wherein the first electrode plate area and the tab adhesive are both free of overlap with the stack body, and the surface of the second electrode plate area is provided with a diaphragm and the second electrode plate area at least partially overlaps with the stack body.
6. The electric cell of claim 5, wherein, The number of the reference electrodes is multiple, and multiple reference electrodes are arranged at different positions on the outer surface of the same positive electrode plate.
7. The electric cell of claim 1, wherein, Each positive electrode plate is provided with one positive electrode tab.
8. The electric cell of claim 7, wherein, Each negative electrode plate is provided with one negative electrode tab.
9. The electric cell of claim 8, wherein, The battery cell further comprises a first external tab and a second external tab. All the positive electrode tabs are connected to the first external tab at the same time, and all the negative electrode tabs are connected to the second external tab at the same time.
10. The electric cell of claim 1, wherein, The number of the positive electrode plates is 1-40.