Columnar battery and power supply device

Abstract

The utility model discloses a columnar battery and a power supply device, the columnar battery comprises a metal shell, a roll core, a cover cap and a sealing ring, the roll core is arranged in the metal shell, the cover cap is arranged at one end of the metal shell, the sealing ring is arranged around the cover cap and is clamped between the cover cap and the inner wall of the metal shell, the columnar battery further comprises at least one reference electrode, and the reference electrode is arranged in the metal shell. The first end of the reference electrode is clamped between the positive plate and the negative plate of the roll core and is separated from the positive plate and the negative plate through a diaphragm; the second end of the reference electrode is led out of the metal shell from the position between the sealing ring and the inner wall of the metal shell, and the reference electrode and the metal shell are arranged in an insulated mode. According to the technical scheme, the reference electrode is arranged without punching, so that the problem of additional sealing design caused by punching is avoided, and the manufacturing difficulty and cost are greatly reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a columnar battery and a power supply device. Background Art

[0002] At present, there are certain difficulties and deficiencies in the electrochemical measurement and characterization of lithium-ion batteries on electrodes. The three-electrode test system is mainly used to characterize the electrochemical performance of batteries such as cycling, rate charge and discharge, high and low temperature charge and discharge, etc. People usually introduce a reference electrode into the battery to monitor the potential changes between the positive and negative electrodes and the reference electrode during the charge and discharge process to evaluate the electrochemical performance of the battery. At present, the three-electrode manufacturing method of existing cylindrical batteries is usually to punch a hole at the top of the metal shell to lead the reference electrode out of the hole. However, this method of leading out the reference electrode by punching a hole requires additional sealing design for the punching position due to the addition of a hole, which greatly increases the manufacturing difficulty and cost. Utility Model Content

[0003] The utility model provides a columnar battery, aiming to reduce the manufacturing difficulty and cost of a three-electrode cylindrical battery.

[0004] To achieve the above-mentioned purpose, the cylindrical battery proposed in the utility model includes a metal shell, a winding core, a cap and a sealing ring, the winding core is installed in the metal shell, the cap is arranged at one end of the metal shell, the sealing ring is arranged around the cap and clamped between the cap and the inner wall of the metal shell, the cylindrical battery also includes at least one reference electrode, the first end of the reference electrode is clamped between the positive electrode sheet and the negative electrode sheet of the winding core, and is separated from the positive electrode sheet and the negative electrode sheet by a diaphragm; the second end of the reference electrode is led out from between the sealing ring and the inner wall of the metal shell to the outside of the metal shell, and the reference electrode and the metal shell are insulated.

[0005] In some embodiments, a via is formed between the outer wall of the sealing ring and the inner wall of the metal shell, the via corresponds one-to-one to the reference electrode, the second end of the reference electrode is led out of the metal shell through the via, and the reference electrode is interference fit with the via.

[0006] In some embodiments, a first groove is provided on the outer peripheral wall of the sealing ring, and the first groove passes through from one end of the sealing ring to the other end, and the via hole is formed by the first groove and the inner wall of the metal shell.

[0007] In some embodiments, the inner wall of the metal shell is configured with a second groove, and the through hole is formed by the second groove and the outer peripheral wall of the sealing ring.

[0008] In some embodiments, the reference electrode includes an exposed section and a coated section, the coated section is coated with an insulating layer, the exposed section is entirely sandwiched between the positive electrode sheet and the negative electrode sheet, and the coated section is led out from between the sealing ring and the inner wall of the metal shell to the outside of the metal shell.

[0009] In some embodiments, the insulating layer includes two pieces of green glue, which are respectively located on both sides of the coating section and are pasted and fixed toward each other; or, the insulating layer includes a piece of green glue, which is bonded and wound on the coating section.

[0010] In some embodiments, the exposed segment is a metal segment treated with concentrated sulfuric acid and vacuum dried; and / or,

[0011] The exposed section is located in the axial center section of the winding core.

[0012] In some embodiments, the reference electrode is a metal wire, a metal line, or a metal sheet.

[0013] In some embodiments, the portion of the reference electrode located between the sealing ring and the inner wall of the metal shell is flat.

[0014] The utility model also provides a power supply device, comprising at least one of the above-mentioned cylindrical batteries.

[0015] According to the technical solution of the utility model, the reference electrode of the cylindrical battery is led out from between the sealing ring and the inner wall of the metal shell to the outside of the metal shell. When the cylindrical battery is sealed, the metal shell will be pressed by two sealing molds to press the sealing ring. Therefore, the reference electrode will be sealed and clamped by the sealing ring and the inner wall of the metal shell, thereby ensuring the sealing of the cylindrical battery. Compared with the prior art, the reference electrode of the technical solution of the utility model does not require punching, thus avoiding the problem of additional sealing design caused by punching, and greatly reducing the manufacturing difficulty and cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a partial cross-sectional and perspective structural schematic diagram of a cylindrical battery in one embodiment of the utility model;

[0017] Figure 2 This is a schematic diagram of the structure when a reference electrode is provided on the winding core in one embodiment of the utility model;

[0018] Figure 3 This is a perspective structural diagram of a winding core in one embodiment of the utility model;

[0019] Figure 4 This is a schematic structural diagram of a cylindrical battery in an embodiment of the utility model when it is not sealed;

[0020] Figure 5 A top view of a sealing ring in one embodiment of the utility model;

[0021] Figure 6 It is an axial cross-sectional view of a sealing ring in one embodiment of the utility model. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0024] It should also be noted that when an element is referred to as being "fixed on" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element at the same time. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0025] In addition, the descriptions of "first", "second", etc. in the present utility model are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0026] The utility model provides a columnar battery, such as a cylindrical battery.

[0027] See also Figures 1 to 3In this embodiment, the cylindrical battery includes a metal shell 10, a winding core 20, a cap 30, a sealing ring 40 and at least one reference electrode 50. The winding core 20 is installed in the metal shell 10, and the winding core 20 is wound together by the negative electrode sheet, the separator 21 and the positive electrode sheet; the cap 30 is arranged at one end of the metal shell 10, and the positive electrode tab 221 (i.e., the cathode tab) of the positive electrode sheet of the winding core 20 is conductively connected to the cap 30, that is, the cap 30 is the positive electrode of the cylindrical battery; the negative electrode tab 231 (i.e., the anode tab) of the negative electrode sheet of the winding core 20 is conductively connected to the metal shell 10, and the metal shell 10 is the negative electrode of the cylindrical battery. The sealing ring 40 is arranged around the cap 30 and clamped between the cap 30 and the inner wall of the metal shell 10 to seal the open end of the metal shell 10 (i.e., the end where the cap 30 is set); the first end of the reference electrode 50 is clamped between the positive electrode sheet and the negative electrode sheet of the winding core 20, and the part of the reference electrode 50 clamped in the winding core 20 is separated from the positive electrode sheet and the negative electrode sheet by the diaphragm 21, that is, it is not short-circuited with the positive electrode sheet and the negative electrode sheet; the second end of the reference electrode 50 is led out from between the sealing ring 40 and the inner wall of the metal shell 10 to the outside of the metal shell 10, and the reference electrode 50 and the metal shell 10 are insulated to avoid short-circuiting between the reference electrode 50 and the negative electrode sheet.

[0028] The insulation between the reference electrode 50 and the metal shell 10 may be provided by providing an insulating material layer on the outer layer of the reference electrode 50, or by coating an insulating material on the inner wall of the metal shell 10 corresponding to the reference electrode 50, etc.

[0029] In this embodiment, a cylindrical battery is provided with one reference electrode 50 as an example; of course, in other embodiments, multiple reference electrodes 50 may be provided, so that when one of the reference electrodes 50 fails due to fracture or other fault problems, other reference electrodes 50 that have not failed may be used to continue measurement.

[0030] In some embodiments, the reference electrode 50 may be a metal wire, a metal line or a metal sheet, etc. The metal housing 10 may be a steel shell or a housing made of other metal materials. In some embodiments, the second end of the reference electrode 50 may also be connected to a nickel sheet.

[0031] Of course, the cylindrical battery also includes existing structures such as insulating sheets and explosion-proof valves provided at both ends of the winding core 20. These existing structures can refer to the conventional cylindrical battery structure and will not be described in detail here.

[0032] The technical solution of the cylindrical battery of this embodiment adopts a setting mode in which the reference electrode 50 is led out from between the sealing ring 40 and the inner wall of the metal shell 10 to the outside of the metal shell 10. When the cylindrical battery is sealed, the metal shell 10 will be pressed by two sealing molds to press the sealing ring 40. Therefore, the reference electrode 50 will be sealed and clamped by the sealing ring 40 and the inner wall of the metal shell 10, which can ensure the sealing of the cylindrical battery. Compared with the prior art, the setting of the reference electrode 50 of the solution of this embodiment does not require drilling, which avoids the problem of additional sealing design caused by drilling, and greatly reduces the manufacturing difficulty and cost.

[0033] The first end of the reference electrode 50 is clamped between the positive electrode sheet and the negative electrode sheet of the winding core 20 by unwinding the winding core 20 (reference electrode 50). Figure 2 ), put the first end of the reference electrode 50 in and separate the reference electrode 50 from the positive and negative electrode sheets by using the diaphragm 21, and then rewind the winding core 20; or, during the winding process of the winding core 20, when the winding core 20 is rolled to a certain size, put the first end of the reference electrode 50 and the corresponding diaphragm 21 in the winding core 20, and continue to complete the winding. In addition, after the winding core 20 is loaded into the metal shell 10 and before the cylindrical battery is sealed, the second end of the reference electrode 50 can be extended to the outside of the open end of the metal shell 10, so that when the cylindrical battery is sealed, the reference electrode 50 is sandwiched between the sealing ring 40 and the inner wall of the metal shell 10.

[0034] In some embodiments, a via is formed between the outer wall of the sealing ring 40 and the inner wall of the metal shell 10, and the via corresponds one-to-one to the reference electrode 50, that is, when there is one reference electrode 50, there is one via, and when there are multiple reference electrodes 50, there are corresponding multiple vias; the second end of the reference electrode 50 is led out of the metal shell 10 through the hole, and the reference electrode 50 and the via are interference fit. Since during the sealing process of the cylindrical battery, the reference electrode 50 may be squeezed and broken when the two sealing molds press the steel shell and the sealing ring 40 against each other, this embodiment provides an embedding area for the reference electrode 50 by adding a through hole between the outer wall of the sealing ring 40 and the inner wall of the metal shell 10. In this way, when the two sealing molds press the steel shell and the sealing ring 40 against each other, the reference electrode 50 is embedded in the through hole, which reduces the squeezing effect on the reference electrode 50 and effectively avoids the reference electrode 50 from being squeezed and broken. In addition, the reference electrode 50 and the through hole have an interference fit, that is, during the sealing process, under the squeezing effect, the sealing ring 40 will tightly wrap the reference electrode 50, which can effectively ensure the sealing.

[0035] The through hole may be a vertical hole extending along the axial direction of the sealing ring 40 , or an inclined hole arranged at a certain angle to the axial direction of the sealing ring 40 , or a hole extending in a zigzag manner.

[0036] Reference Figure 5 and Figure 6 In some embodiments, a first groove 41 is provided on the outer peripheral wall of the sealing ring 40, and the first groove 41 runs through from one end of the sealing ring 40 to the other end, and a through hole is formed by the first groove 41 and the inner wall of the metal shell 10, that is, the reference electrode 50 is squeezed by the inner wall of the metal shell 10 to be inserted into the first groove 41. The first groove 41 may be a through groove arranged along the axial direction of the sealing ring 40, or a through groove arranged at a certain angle to the axial direction of the sealing ring 40, or a through groove extending in a zigzag manner.

[0037] In some other embodiments, the via hole may also be: a second groove is constructed on the inner wall of the metal shell 10 , and the via hole is formed by the second groove and the outer peripheral wall of the sealing ring 40 .

[0038] In some embodiments, the portion of the reference electrode 50 between the sealing ring 40 and the inner wall of the metal shell 10 is flat (eg, sheet-shaped), which can better ensure the sealing effect between the metal shell 10 and the sealing ring 40 .

[0039] Reference Figures 1 to 4 In some embodiments, the reference electrode 50 includes an exposed section 51 and a coated section 52, the coated section 52 is coated with an insulating layer, the exposed section 51 is entirely sandwiched between the positive electrode sheet and the negative electrode sheet, and the coated section 52 is led out from between the sealing ring 40 and the inner wall of the metal shell 10 to the outside of the metal shell 10. Since the coated section 52 is coated with the insulating layer, insulation is achieved between the coated section 52 and the inner wall of the metal shell 10.

[0040] In some embodiments, a portion or a small section of the coated segment 52 close to the exposed segment 51 can also be clamped in the core 20 (between the positive and negative electrodes) to prevent the exposed segment 51 from moving from the end of the core 20 to the outside of the core 20 after the cylindrical battery has been used for a long time, causing the reference electrode 50 to fail or other safety failures.

[0041] In some embodiments, the exposed section 51 is located in the axial center section of the winding core 20 to ensure stable operation of the reference electrode 50. Even if the cylindrical battery is used for a long time and the electrolyte at the end of the winding core 20 is reduced, the data of the cylindrical battery can be measured more accurately.

[0042] In some embodiments, the exposed section 51 can be a metal material section treated with concentrated sulfuric acid and vacuum dried. For example, a portion of the first end of the reference electrode 50 is immersed in pretreated concentrated sulfuric acid for 2 hours to remove the oxide layer and surface protective layer on the metal surface, and then baked for 2 hours under 80°C vacuum conditions to obtain a metal material section treated with concentrated sulfuric acid and vacuum dried (i.e., the exposed section 51). After obtaining the exposed section 51, it is then wrapped in the winding core 20. In this embodiment, the exposed section 51 is immersed in concentrated sulfuric acid to remove the oxide layer and protective layer, so that the data measured by the reference electrode 50 is more accurate.

[0043] In some embodiments, the insulating layer includes two pieces of green glue, which are respectively located on both sides of the coating section 52 and are pasted and fixed to each other; that is, the two pieces of green glue are pasted to form a coating layer to wrap the coating section 52 between the two pieces of green glue. This embodiment solves the insulation problem of the reference electrode 50 through a simple structure of two pieces of green glue pasted to each other, with low cost, simple processing and good reliability; in addition, only the thickness of the two pieces of green glue is added to the thickness of the reference electrode 50, and the impact on the energy density of the winding core 20 is very small.

[0044] In other embodiments, the insulating layer includes a piece of green glue, which is bonded and wound on the coating section 52. In this embodiment, a piece of green glue is wound on the coating section 52 to achieve surface insulation treatment of the coating section 52. Similarly, the insulation problem of the reference electrode 50 is solved with a simple green glue structure, which is low in cost, simple to handle, and has good reliability. Of course, in other embodiments, the reference electrode 50 can also adopt other insulation treatment solutions.

[0045] The utility model also proposes a power supply device, including at least one of the above-mentioned cylindrical batteries. The specific structure of the cylindrical battery refers to the above-mentioned embodiment. Since the power supply device adopts all the technical solutions of all the above-mentioned cylindrical battery embodiments, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here. For example, the power supply device can be a new energy vehicle battery, a power bank or a battery of an electronic device.

[0046] The above description is only a partial or preferred embodiment of the present invention. Neither the text nor the drawings can limit the scope of protection of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the overall concept of the present invention, or direct / indirect application in other related technical fields are included in the scope of protection of the present invention.

Claims

1. A cylindrical battery, comprising a metal shell, a winding core, a cap and a sealing ring, wherein the winding core is installed in the metal shell, the cap is arranged at one end of the metal shell, the sealing ring is arranged around the cap and clamped between the cap and the inner wall of the metal shell, characterized in that: It also includes at least one reference electrode, a first end of which is clamped between the positive electrode sheet and the negative electrode sheet of the winding core, and is separated from the positive electrode sheet and the negative electrode sheet by a diaphragm; a second end of the reference electrode is led out from between the sealing ring and the inner wall of the metal shell to the outside of the metal shell, and the reference electrode and the metal shell are insulated.

2. The cylindrical battery according to claim 1, characterized in that: A via is formed between the outer wall of the sealing ring and the inner wall of the metal shell, the via corresponds to the reference electrode one by one, the second end of the reference electrode is led out of the metal shell through the via, and the reference electrode is interference fit with the via.

3. The cylindrical battery according to claim 2, characterized in that: A first groove is provided on the outer peripheral wall of the sealing ring, and the first groove passes through from one end of the sealing ring to the other end. The through hole is formed by the first groove and the inner wall of the metal shell.

4. The cylindrical battery according to claim 2, characterized in that: The inner wall of the metal shell is configured with a second groove, and the through hole is formed by enclosing the second groove and the outer peripheral wall of the sealing ring.

5. The cylindrical battery according to any one of claims 1 to 4, characterized in that: The reference electrode includes an exposed section and a coated section, wherein the coated section is coated with an insulating layer, the exposed section is entirely sandwiched between the positive electrode sheet and the negative electrode sheet, and the coated section is led out from between the sealing ring and the inner wall of the metal shell to the outside of the metal shell.

6. The cylindrical battery according to claim 5, characterized in that: The insulating layer includes two pieces of green glue, which are respectively located on both sides of the coating section and are pasted and fixed toward each other; or, the insulating layer includes one piece of green glue, which is adhered and wound on the coating section.

7. The cylindrical battery according to claim 5, characterized in that: The exposed section is a metal section treated with concentrated sulfuric acid and vacuum dried; and / or, The exposed section is located in the axial center section of the winding core.

8. The cylindrical battery according to any one of claims 1 to 4, characterized in that: The reference electrode is a metal wire, a metal line or a metal sheet.

9. The cylindrical battery according to any one of claims 1 to 4, characterized in that: The portion of the reference electrode located between the sealing ring and the inner wall of the metal shell is flat.

10. A power supply device, characterized in that: The invention comprises at least one cylindrical battery according to any one of claims 1 to 9.

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