Three-electrode cell and battery

Abstract

The utility model discloses a three-electrode cell and a battery, the three-electrode cell comprises a reference electrode and a negative plate, and the reference electrode comprises a copper wire and a lithium plate coated on the peripheral side of the copper wire; the reference electrode is positioned on the negative plate. According to the three-electrode battery cell disclosed by the utility model, the three-electrode battery cell comprises a reference electrode and a negative plate, and the reference electrode is positioned on the negative plate and is used for collecting potential change of the negative plate in a charging and discharging process; the reference electrode is directly compounded with the lithium sheet by adopting the copper wire, so that the steps of soaking the copper wire and plating the copper wire with lithium can be omitted, the manufacturing process is simplified, the manufacturing cost of the reference electrode can be reduced, and the success rate of testing the potential change of the negative plate by the reference electrode is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery technology field especially is related to a three electrode electric core and battery. BACKGROUND

[0002] In the related art, the three electrode electric core is an important component for evaluating fast charging limit current and charging pulse current (HPPC), and the three electrode manufacturing needs to use concentrated sulfuric acid to soak copper wire in advance. There are certain safety hazards and high cost in the soaking process. The soaked copper wire becomes thin and soft, and there is a risk of breakage in the subsequent manufacturing process. In the subsequent preparation, lithium needs to be plated on the copper wire, and the failure rate of this process is high. There is a risk of lithium falling in the later stage, which affects the test progress. SUMMARY

[0003] The utility model aims at at least one of the technical problems existing in the prior art. To this end, one purpose of the utility model is to provide a three electrode electric core. The reference electrode is directly composed of copper wire and lithium sheet, which can save the steps of soaking copper wire and plating lithium on copper wire, simplify the manufacturing process, reduce the manufacturing cost of the reference electrode, and improve the success rate of testing the potential change of the negative plate of the reference electrode.

[0004] The utility model further provides a battery with the above-mentioned three electrode electric core.

[0005] The utility model further provides a power consumption equipment with the above-mentioned battery.

[0006] According to the three electrode electric core of the first aspect of the utility model, the reference electrode includes copper wire and lithium sheet wrapped around the outer periphery of the copper wire. The reference electrode is located on the negative plate.

[0007] According to the three electrode electric core of the utility model, the three electrode electric core includes a reference electrode and a negative plate. The reference electrode is located on the negative plate and is used to collect the potential change of the negative plate during charging and discharging. The reference electrode is directly composed of copper wire and lithium sheet, which can save the steps of soaking copper wire and plating lithium on copper wire, simplify the manufacturing process, reduce the manufacturing cost of the reference electrode, and improve the success rate of testing the potential change of the negative plate of the reference electrode.

[0008] According to some embodiments of the utility model, the negative plate includes a central region, and the central region is provided with the reference electrode.

[0009] According to some embodiments of the utility model, the three electrode electric core further includes a negative tab connected to one end of the negative plate. The negative plate includes a body region and a transition region. The transition region is located at one end of the body region close to the negative tab. The thickness of the transition region is less than that of the body region. The transition region is provided with the reference electrode.

[0010] According to some embodiments of the present application, the three-electrode battery further comprises: a cover plate, wherein an explosion-proof valve is arranged on the cover plate, a through hole is arranged on the explosion-proof valve, and the copper wire is arranged in the through hole.

[0011] According to some embodiments of the present application, the diameter D of the through hole satisfies: 1mm≤D≤3mm.

[0012] According to some embodiments of the present application, the cover plate further comprises an explosion-proof valve patch arranged opposite to the explosion-proof valve, the explosion-proof valve patch is located on the side of the explosion-proof valve away from the negative plate, the copper wire is wound between the explosion-proof valve and the explosion-proof valve patch, the explosion-proof valve patch has a communication hole in communication with the through hole, and the copper wire is arranged in the communication hole.

[0013] According to some embodiments of the present application, the width A of the lithium sheet satisfies: 1mm≤A≤3mm, and the length B of the lithium sheet satisfies: 1mm≤B≤3mm.

[0014] According to some embodiments of the present application, the copper wire is fixed on the negative plate.

[0015] According to the battery of the second aspect of the present application, the battery comprises the three-electrode battery according to the first aspect of the present application.

[0016] According to the battery of the present application, by arranging the three-electrode battery, one reference electrode is used to collect the potential change of the negative plate in the charging and discharging process, and one reference electrode is used to monitor the lithium precipitation potential of the transition zone of the negative plate, the reference electrode is directly compounded with the lithium sheet by using the copper wire, the manufacturing process is simplified, the manufacturing cost of the reference electrode is reduced, the success rate of testing the potential change of the negative plate by the reference electrode is improved, and the performance of the battery is improved.

[0017] According to the battery of the present application, the battery is a blade lithium ion battery.

[0018] The additional aspects and advantages of the present application will be partially given in the following description, partially will become obvious from the following description, or will be understood by the practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0019] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, in which:

[0020] Figure 1 is a schematic view of the cooperation of the reference electrode and the negative plate according to some embodiments of the present application.

[0021] REFERENCE NUMERALS

[0022] 10, reference electrode; 11, copper wire; 12, lithium sheet;

[0023] 20, negative electrode sheet; 21, body region; 22, transition region; 23, negative electrode tab;

[0024] 30, cover plate; 31, explosion-proof valve; 311, through hole;

[0025] 40, insulating sticker. DETAILED DESCRIPTION

[0026] The embodiments of the present application are described in detail below, examples of which are shown in the drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by reference to the drawings are exemplary only, and are used only for explaining the present application, and cannot be understood as a limitation of the present application.

[0027] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application. In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features limited by "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0028] In the description of the present application, it should be noted that, unless otherwise specifically defined and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0029] Reference is made below to Figure 1 A three-electrode battery cell according to an embodiment of the present application is described.

[0030] According to the three-electrode battery cell of the first aspect of the present application, the three-electrode battery cell comprises a reference electrode 10, and further comprises a positive electrode and a negative electrode, the reference electrode 10 can be used to directly measure the potential difference between the positive electrode, the negative electrode and the electrolyte, can be used to measure the electrochemical reaction process inside the three-electrode battery cell, especially the potential change of each electrode in the charging and discharging process, which can help researchers to optimize the design parameters of the battery, such as the selection of electrode material, electrolyte formula and separator material; through the accurate measurement of the potential change, the overall performance of the battery is improved.

[0031] The reference electrode 10 is located on the negative electrode sheet 20 and is used to monitor the potential change of the negative electrode sheet 20 in the charging and discharging process, the lithium sheet 12 of the reference electrode 10 is used to collect the potential signal of the negative electrode sheet 20 in the charging and discharging process, and the copper wire 11 conducts the collected potential signal to the electrochemical workstation.

[0032] The negative electrode sheet 20 will have complex electrochemical reactions in the charging and discharging process of the battery cell, and the electrochemical reactions directly affect the performance and life of the battery. By placing the reference electrode 10 on the negative electrode sheet 20, the potential change of the negative electrode sheet 20 can be directly measured, so that the electrochemical behavior of the negative electrode sheet 20 can be more accurately understood.

[0033] The reference electrode 10 comprises a copper wire 11 and a lithium sheet 12, the lithium sheet 12 is wrapped on the outer circumferential side of the copper wire 11, the direct combination of the copper wire 11 and the lithium sheet 12 can save the steps of soaking the copper wire 11 and plating lithium on the copper wire 11, simplify the manufacturing process, reduce the manufacturing cost of the reference electrode 10, and after the combination of the copper wire 11 and the lithium sheet 12, the lithium sheet 12 is not easy to fall off from the copper wire 11, thereby improving the success rate of the reference electrode 10 in testing the potential change.

[0034] For example, when the lithium raw material is in a molten state, the copper wire 11 is embedded in the lithium raw material, and when the lithium raw material solidifies into a lithium sheet 12, the copper wire 11 can be fixed in the lithium sheet 12, the process of soaking the copper wire 11 in concentrated sulfuric acid and plating lithium on the copper wire 11 can be saved, the structural strength of the copper wire 11 itself can be improved, and the manufacturing cost of the reference electrode 10 can be reduced. The lithium raw material in a molten state can be completely wrapped on the outer circumferential side of the copper wire 11, so that after the lithium raw material solidifies into a lithium sheet 12, the lithium sheet 12 can completely wrap the copper wire 11, that is, the lithium sheet 12 has a certain thickness, and the thickness of the lithium sheet 12 is greater than the thickness of the copper wire 11, and the thickness of the copper wire 11 is between 10 μm-1000 μm.

[0035] According to the three-electrode battery cell, the reference electrode 10 is directly combined with the lithium sheet 12 through the copper wire 11, the steps of soaking the copper wire 11 and plating lithium on the copper wire 11 can be omitted, the manufacturing process is simplified, the manufacturing cost of the reference electrode 10 can be reduced, and the success rate of testing the potential change of the negative plate 20 by the reference electrode 10 is improved.

[0036] According to some embodiments of the utility model, refer to Figure 1 , the negative plate 20 includes a center area, the center area is provided with the reference electrode 10, and the center area of the negative plate 20 is the center position of the negative plate 20 in length and width. On the one hand, the center area of the negative plate 20 is the area with the most uniform potential distribution on the negative plate 20, and placing the reference electrode 10 in the center area can improve the accuracy of measurement and ensure that the measured potential change can truly reflect the overall electrochemical behavior of the negative plate 20. On the other hand, placing the reference electrode 10 in the center area can reduce the risk of contact between the reference electrode 10 and the positive plate, thereby reducing the risk of short circuit of the three-electrode battery cell. In addition, the edge area of the negative plate 20 can be more easily affected by factors such as electrolyte flow and current density change, resulting in uneven distribution of potential. Placing the reference electrode 10 in the center area can reduce the influence of these edge effects and ensure that the measured potential is more uniform and more representative.

[0037] According to some embodiments of the utility model, refer to Figure 1 , the three-electrode battery cell further includes: a negative tab 23 connected to one end of the negative plate 20, the negative plate 20 includes a body area 21 and a transition area 22, the transition area 22 is located at one end of the body area 21 close to the negative tab 23, and the thickness of the transition area 22 is less than the thickness of the body area 21. The negative plate 20 includes a negative plate 20 body and an active material coated on the negative plate 20 body, and the active material can be one of carbon black, conductive graphite, carbon nanotubes (CNTs) or graphene. The thickness of the active material coated on the transition area 22 is lower than the thickness of the active material coated on the body area 21, and the transition area 22 is provided with the reference electrode 10.

[0038] The transition area 22 of the negative plate 20 is prone to lithium deposition, and placing the reference electrode 10 in the transition area 22 can also monitor the lithium deposition potential of the negative plate 20 and comprehensively evaluate the limiting current of the negative plate 20.

[0039] According to some embodiments of the utility model, refer to Figure 1The three-electrode battery further comprises a cover plate 30, the cover plate 30 is provided with an explosion-proof valve 31, the explosion-proof valve 31 is provided with a through hole 311, the copper wire 11 is arranged in the through hole 311, and the copper wire 11 can be led out of the three-electrode battery, so that the copper wire 11 is convenient to be connected with an external electrochemical workstation. Specifically, the thickness of the explosion-proof valve 31 is thinner than the thickness of the cover plate 30, the through hole 311 can be easily machined on the explosion-proof valve 31, and it is not necessary to adopt a drill to drill a hole, so that the operation is simple and convenient.

[0040] According to some embodiments of the present application, referring to Figure 1 The diameter D of the through hole 311 satisfies 1mm≤D≤3mm, and the diameter of the through hole 311 in this range can facilitate the copper wire 11 to be led out of the through hole 311. If the diameter of the through hole 311 is greater than 3mm, the area of the through hole 311 occupies a large proportion of the area of the explosion-proof valve 31, and the gas in the battery monomer is easy to leak from the through hole 311, which is not conducive to the safety of the three-electrode battery; if the diameter of the through hole 311 is less than 1mm, the diameter of the through hole 311 is too small, which may cause the copper wire 11 to be unable to be led out of the through hole 311. For example, the diameter of the through hole 311 can be 1mm, 2mm, 2.5mm or 3mm, etc.

[0041] In a specific example, the three-electrode battery is provided with two reference electrodes 10, one reference electrode 10 is arranged in the center area of the negative plate 20, and is used to collect the potential change of the negative plate 20 in the charging and discharging process, and the other reference electrode 10 is arranged in the transition area 22 of the negative plate 20, and is used to monitor the lithium precipitation potential of the transition area 22 of the negative plate 20; the copper wire 11 of the two reference electrodes 10 can be led out of one through hole 311.

[0042] According to some embodiments of the present application, referring to Figure 1 The cover plate 30 is further provided with an explosion-proof valve patch, the explosion-proof valve patch is arranged opposite to the explosion-proof valve 31, the explosion-proof valve patch is located on the side of the explosion-proof valve 31 away from the negative plate 20, and the explosion-proof valve patch is used to protect the explosion-proof valve 31 and prevent external structural parts from impacting the explosion-proof valve 31, thereby improving the safety of the explosion-proof valve 31.

[0043] The copper wire 11 is wound between the explosion-proof valve 31 and the explosion-proof valve patch, and the excess copper wire 11 is placed between the explosion-proof valve 31 and the explosion-proof valve patch after winding, so as to protect the copper wire 11 and reduce the risk of breakage of the copper wire 11 in the manufacturing process. The explosion-proof valve patch has a communication hole in communication with the through hole 311, the copper wire 11 is arranged in the communication hole, and the copper wire 11 is led out from the inner side of the explosion-proof valve patch through the communication hole.

[0044] According to some embodiments of the present application, referring to Figure 1The width A of the lithium sheet 12 satisfies 1mm≤A≤3mm, and the length B of the lithium sheet 12 satisfies 1mm≤B≤3mm. The width and the length of the lithium sheet 12 are arranged in the range, so that the lithium sheet 12 can better collect the potential change of the negative electrode sheet 20. For example, the width of the lithium sheet 12 can be 1mm, 2mm, 2.5mm or 3mm, etc., and the length of the lithium sheet 12 can be 1mm, 2mm, 2.5mm or 3mm, etc. Preferably, the width of the lithium sheet 12 is 2mm, and the length of the lithium sheet 12 is 2mm.

[0045] According to some embodiments of the utility model, referring to Figure 1 The copper wire 11 is fixed on the negative electrode sheet 20, and the copper wire 11 is led out from the lithium sheet 12 to the outside of the three-electrode battery cell. The copper wire 11 is fixed on the negative electrode sheet 20, so that the position of the copper wire 11 can be avoided from being dislocated. For example, the copper wire 11 can be fixed on the negative electrode sheet 20 by using the insulating adhesive tape 40.

[0046] The battery according to the second aspect of the utility model comprises the three-electrode battery cell according to the first aspect of the utility model.

[0047] The battery according to the utility model has the advantages that by arranging the three-electrode battery cell, one reference electrode 10 is used to collect the potential change of the negative electrode sheet 20 in the charging and discharging process, and one reference electrode 10 is used to monitor the lithium precipitation potential of the transition zone 22 of the negative electrode sheet 20. The reference electrode 10 is directly compounded with the lithium sheet 12 by using the copper wire 11, so that the manufacturing process is simplified, the manufacturing cost of the reference electrode 10 is reduced, the success rate of the reference electrode 10 in testing the potential change of the negative electrode sheet 20 is improved, and the performance of the battery is improved.

[0048] The battery according to the utility model has the advantages that by arranging the three-electrode battery cell, one reference electrode 10 is used to collect the potential change of the negative electrode sheet 20 in the charging and discharging process, and one reference electrode 10 is used to monitor the lithium precipitation potential of the transition zone 22 of the negative electrode sheet 20. The reference electrode 10 is directly compounded with the lithium sheet 12 by using the copper wire 11, so that the manufacturing process is simplified, the manufacturing cost of the reference electrode 10 is reduced, the success rate of the reference electrode 10 in testing the potential change of the negative electrode sheet 20 is improved, and the performance of the battery is improved. Figure 1 The battery according to the utility model has the advantages that by arranging the three-electrode battery cell, one reference electrode 10 is used to collect the potential change of the negative electrode sheet 20 in the charging and discharging process, and one reference electrode 10 is used to monitor the lithium precipitation potential of the transition zone 22 of the negative electrode sheet 20. The reference electrode 10 is directly compounded with the lithium sheet 12 by using the copper wire 11, so that the manufacturing process is simplified, the manufacturing cost of the reference electrode 10 is reduced, the success rate of the reference electrode 10 in testing the potential change of the negative electrode sheet 20 is improved, and the performance of the battery is improved.

[0049] The electrical equipment according to the second aspect of the utility model comprises the battery according to the second aspect of the utility model.

[0050] The electrical equipment according to the utility model has the advantages that by arranging the battery, the reference electrode 10 is directly compounded with the lithium sheet 12 by using the copper wire 11, so that the manufacturing process is simplified, the manufacturing cost of the reference electrode 10 is reduced, the success rate of the reference electrode 10 in testing the potential change of the negative electrode sheet 20 is improved, and the performance of the battery is improved.

[0051] In the description of the specification, the description of the terms "some embodiments", "optionally", "further", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present application. In the description of the specification, the illustrative description of the above terms does not necessarily mean the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0052] Although the embodiments of the present application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and purposes of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A three-electrode cell, characterized in that, The application relates to a lithium ion battery, comprising: a reference electrode, the reference electrode comprising a copper wire and a lithium sheet wrapped around the copper wire; a negative electrode sheet, the reference electrode being arranged on the negative electrode sheet.

2. The three-electrode cell of claim 1, wherein, The negative electrode sheet comprises a central region, and the central region is provided with the reference electrode.

3. The three-electrode cell of claim 1, wherein, Further comprising: a negative electrode tab, the negative electrode tab being connected to one end of the negative electrode sheet, the negative electrode sheet comprising a body region and a transition region, the transition region being arranged at one end of the body region close to the negative electrode tab, the thickness of the transition region being smaller than the thickness of the body region, and the transition region being provided with the reference electrode.

4. The three-electrode cell of claim 1, wherein, Further comprising: a cover plate, the cover plate being provided with an explosion-proof valve, the explosion-proof valve being provided with a through hole, and the copper wire being arranged in the through hole.

5. The three-electrode cell of claim 4, wherein, The diameter of the through hole is D, and 1mm<=D<=3mm.

6. The three-electrode cell of claim 4, wherein, The cover plate is further provided with an explosion-proof valve patch arranged opposite to the explosion-proof valve, the explosion-proof valve patch being arranged on the side of the explosion-proof valve away from the negative electrode sheet, the copper wire being wound between the explosion-proof valve and the explosion-proof valve patch, the explosion-proof valve patch being provided with a communication hole in communication with the through hole, and the copper wire being arranged in the communication hole.

7. The three-electrode cell of claim 1, wherein, The width of the lithium sheet is A, and 1mm<=A<=3mm; and the length of the lithium sheet is B, and 1mm<=B<=3mm.

8. The three-electrode cell of claim 1, wherein, The copper wire is fixed on the negative electrode sheet.

9. A battery, characterized by The application further relates to a three-electrode battery cell, comprising: the three-electrode battery cell according to any one of claims 1-8.

10. The battery of claim 9, wherein, The battery is a blade lithium ion battery.

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