Battery monomer

Abstract

The utility model provides a single battery. The single battery comprises a shell, a positive pole, a negative pole and an electrode assembly, the positive pole and the negative pole are insulated and fixed at the top of the shell; one part of the positive pole and one part of the negative pole extend out of the shell, the extending part is provided with a mounting part for mounting a heat transfer tube, and the other part of the positive pole and the other part of the negative pole extend into the shell and are connected with an electrode assembly arranged in the shell; and sealing unpacking pieces are arranged at the top and the bottom of the shell. According to the utility model, when the single batteries are adopted to form the battery module, the two sealing unpacking pieces of each single battery are opened, and the two channels are respectively connected with the single batteries, so that the single batteries in the battery module are in a unified electrolyte system and a unified pressure system at the same time; therefore, the consumption of each battery monomer in the battery module can be always kept consistent, and the air pressure can also be kept consistent, so that the performance of the battery module can be greatly improved.

Description

Technical Field

[0001] The utility model relates to the field of batteries, in particular to a battery monomer. Background Art

[0002] Currently, multiple battery cells are connected in parallel or in series to form a battery module or battery pack.

[0003] When existing battery modules are assembled into strings, although each battery cell is sorted by capacity, there are still certain differences in the initial capacity of each battery cell. After the battery module has been running for a period of time, the electrolyte consumption of each battery cell is different, resulting in a continuous gap in the capacity and capacity retention rate of each battery cell, which will reduce the cycle life of the battery module. At the same time, the gas production of each battery cell is also different, the internal pressure of each battery cell is also different, and the expansion degree of the battery cell shell is different, which will further affect the performance of the battery module. Utility Model Content

[0004] In order to solve the problem that the cycle life of the battery module is affected due to poor consistency of the battery cells in the existing battery module, the utility model provides a battery cell.

[0005] The battery cell comprises a housing, a positive electrode column, a negative electrode column and an electrode assembly;

[0006] The positive electrode column and the negative electrode column are insulated and fixed on the top of the shell; a part of the positive electrode column and the negative electrode column extends out of the shell, and the extended part is provided with a mounting portion for mounting a heat transfer tube, and the other part of the positive electrode column and the negative electrode column extends into the shell and is connected to the electrode assembly arranged in the shell; there is electrolyte in the shell; a first sealed opening piece is arranged on the top of the shell; and a second sealed opening piece is arranged on the bottom of the shell.

[0007] The utility model adopts battery cells to form a battery module. Since the battery cells are provided with a first sealed opening piece and a second sealed opening piece, when the battery module is formed, the first sealed opening piece and the second sealed opening piece of each battery cell are opened, and air holes and liquid holes are formed on the battery cells. After the air holes and liquid holes of each battery cell are respectively connected by two channels, each battery cell in the battery module is in a unified electrolyte system and also in a unified pressure system. Therefore, the consumption of each battery cell in the battery module can always be kept consistent, and the air pressure can also be kept consistent, thereby greatly improving the performance of the battery module.

[0008] In addition, the battery cell pole of the utility model is provided with a mounting portion for mounting a heat transfer tube. When a battery module is formed, the heat transfer tube cooperates with each battery cell pole, so that the pole part where the heat of the battery cell is most concentrated can be cooled, thereby improving the safety of the battery module.

[0009] Furthermore, the first sealed package opening component and the second sealed package opening component are both dissolving mechanisms that can be dissolved in electrolyte.

[0010] Furthermore, the first sealing and opening package component is a sealing mechanism that can be opened by external force, and the second sealing and opening package component is a dissolving mechanism that can be dissolved in electrolyte.

[0011] Furthermore, the first sealing and opening package component is a dissolving mechanism that can be dissolved in the electrolyte, and the second sealing and opening package component is a sealing mechanism that can be opened by external force.

[0012] Furthermore, the dissolving mechanism comprises an isolation layer arranged toward the inside of the shell and a dissolving layer arranged toward the outside of the shell and made of electrolyte additive material.

[0013] Furthermore, the sealing mechanism opened by external force is a magnet; the magnet includes an iron sheet and a protective layer covering the outside of the iron sheet.

[0014] Furthermore, the outer shell portion corresponding to the sealing mechanism opened by the external force is a weak area of ​​the outer shell.

[0015] Furthermore, the mounting portion is a groove or a through hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a three-dimensional structural diagram of a battery cell;

[0018] Figure 2 Schematic diagram of the structure of a battery cell Figure 1 ;

[0019] Figure 3 Schematic diagram of the structure of a battery cell Figure 2 ;

[0020] Figure 4 is a schematic diagram of the dissolution mechanism;

[0021] Figure 5 It is a schematic diagram of the structure of a pull-ring type package opening piece;

[0022] Figure 6 It is a schematic diagram of the structure of a U-shaped package opening piece;

[0023] Figure 7 It is a schematic diagram of unpacking by using U-shaped unpacking;

[0024] Figure 8 It is a schematic diagram of the structure of the magnet unpacking component.

[0025] The figure is labeled as follows:

[0026] 100-battery cell, 1-housing, 11-cylinder, 12-upper cover, 13-lower cover, 2-positive pole, 3-negative pole, 4-installation portion, 5-first sealing opening piece, 6-second sealing opening piece, 7-dissolving mechanism, 71-isolating layer, 72-dissolving layer, 8-sealing mechanism opened by external force, 81-sealing sheet, 82-pull ring, 83-U-shaped connecting sheet, 84-folding edge, 85-push rod, 86-magnet opening piece. DETAILED DESCRIPTION

[0027] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the utility model, but not all of them. Based on the embodiments of the utility model, all other embodiments obtained by ordinary persons in the field without creative work should fall within the scope of protection of the utility model.

[0028] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0029] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "top, bottom" etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first, second, third, fourth, etc." are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0030] like Figure 1 As shown, this embodiment provides a battery cell 100 including a housing 1, a positive electrode column 2, a negative electrode column 3 and an electrode assembly; the electrode assembly is composed of a positive electrode, a separator and a negative electrode arranged in sequence and assembled by a lamination or winding process;

[0031] The positive electrode column 2 and the negative electrode column 3 are insulated and fixed on the top of the shell; a part of the positive electrode column 2 and the negative electrode column 3 extends out of the shell, and a mounting portion 4 for mounting a heat transfer tube is provided on the extended portion, and another part of the positive electrode column 2 and the negative electrode column 3 extends into the shell 1, the part of the positive electrode column 2 extending into the shell is connected to the positive electrode of the electrode assembly, and the part of the negative electrode column 3 extending into the shell is connected to the negative electrode of the electrode assembly, and the shell 1 contains electrolyte;

[0032] A first sealing opening piece 5 is arranged at the top of the shell 1 ; a second sealing opening piece 6 is arranged at the bottom of the shell 1 .

[0033] See also Figure 2 and Figure 3 As shown, the first sealed package opening member 5 and the second sealed package opening member 6 have various forms:

[0034] Form 1: Both the first sealed opening package member 5 and the second sealed opening package member 6 are dissolving mechanisms 7 that can be dissolved in the electrolyte.

[0035] Form 2: Both the first sealing package opening member 5 and the second sealing package opening member 6 are sealing mechanisms 8 that are opened by external force.

[0036] Form three: the first sealing and opening package component 5 is a sealing mechanism 8 that can be opened by external force, and the second sealing and opening package component 6 is a dissolving mechanism 7 that can be dissolved in the electrolyte.

[0037] Form 4: The first sealing and opening package component 5 is a dissolving mechanism 7 that can be dissolved in the electrolyte, and the second sealing and opening package component 6 is a sealing mechanism 8 that can be opened by external force.

[0038] The dissolving mechanism 7 has the following forms:

[0039] 1. The dissolving mechanism 7 is a dissolving film that can be dissolved in the electrolyte. The dissolving film is made of materials such as polystyrene (PS), polymethyl methacrylate (PMMA), thermoplastic polyurethane elastomer rubber (TPU), polyacrylate resin copolymer (SMMA), and engineering plastics (ASA).

[0040] 2. If Figure 4 As shown, the dissolving mechanism 7 is a composite structure consisting of an isolation layer 71 insoluble in the electrolyte and a dissolving layer 72 soluble in the electrolyte, wherein the isolation membrane is made of polyethylene film or polypropylene film; the dissolving membrane is made of polystyrene (PS), polymethyl methacrylate (PMMA), thermoplastic polyurethane elastomer rubber (TPU), polyacrylate resin copolymer (SMMA), engineering plastic (ASA) and other materials.

[0041] 3. The dissolving mechanism 7 is a composite structure consisting of an isolation layer 71 insoluble in the electrolyte and a dissolving layer 72 soluble in the electrolyte and made of an electrolyte additive, wherein the isolation layer is made of polyethylene film or polypropylene film; and the dissolving layer is made of materials such as propylene sulfate, ethylene carbonate, or diphenyl carbonate.

[0042] Among them, propylene sulfate, as an electrolyte additive, can improve the low-temperature performance of the electrolyte and prevent PC molecules from being embedded in the graphite electrode;

[0043] As an electrolyte additive, ethylene carbonate has the following functions:

[0044] 1. Transferring ions in battery reactions: In a battery, when the positive electrode and the negative electrode react, the ions need to move in the battery to complete the reaction. Ethylene carbonate acts as an electrolyte to transfer ions and promote the reaction.

[0045] 2. Maintain charge balance: In the battery reaction, the positive and negative electrodes will consume or release charge. The charge needs to be balanced, otherwise it will affect the battery performance and life. Ethylene carbonate can maintain the charge balance in the battery by transferring ions to ensure the normal operation of the battery.

[0046] 3. Improve battery performance: improve battery conductivity, and enhance battery stability and safety.

[0047] As an electrolyte additive, diphenyl carbonate has good redox stability and thermal stability, can provide high conductivity and extend battery life.

[0048] Therefore, in actual use, any one of the above three substances can be selected as the material to make the column according to the needs, and then the performance of the battery can be improved and enhanced from different aspects.

[0049] The sealing mechanism 8 opened by external force has several forms:

[0050] 1. If Figure 5 As shown, a pull-ring type package opening piece is provided, including a sealing sheet 81 and a pull ring 82; this form is similar to the pull-ring structure of a can; when opening the package, a tool such as a traction rope can be used to open the battery cell.

[0051] 2. If Figure 6 and Figure 7 A U-shaped opening piece is provided; the opening piece includes a U-shaped connecting piece 83 and folded edges 84 arranged on both sides of the U-shaped connecting piece and folded outward; the U-shaped connecting piece 83 is fixed to the cover body, and under the action of external force, the opening piece and the weak area are separated from the cover body to form an opening in the battery cover. When opening the package, the push rod 85 can be used to open the battery cell.

[0052] 3. If Figure 8 As shown, a magnetic opening piece 86 is provided; the magnetic opening piece 86 comprises an iron sheet and a protective layer covering the iron sheet; when opening the package, a permanent magnet or an electromagnet can be used to attract the magnet to realize the opening of the battery cell.

[0053] In order to enable the sealing mechanism 8 opened by external force to fall off smoothly from the battery cell shell, in the present embodiment, the shell portion corresponding to the sealing mechanism 8 opened by external force is a weak area of ​​the shell 1, and the weak area is an area with a thickness less than that of the shell, which is generally formed by stamping or milling, or the weak area is an area encircled by a circle of annular grooves.

[0054] In addition, the battery cell housing has two structural forms, see Figures 1 to 3 As shown:

[0055] The first type of housing 1 includes a cylinder 11 and an upper cover plate 12; the cylinder 11 is an open structure at the upper end and a closed structure at the lower end; when assembling the battery cell, the positive and negative poles of the upper cover plate 12 are first connected to the positive and negative poles of the electrode assembly, and then the upper cover plate 12 and the electrode assembly are placed as a whole from the upper open end of the cylinder 11 into the cylinder 11, and finally the upper cover plate 12 and the open end of the cylinder 11 are welded;

[0056] The second type of shell includes a cylinder 11, an upper cover plate 12 and a lower cover plate 13; the cylinder 11 is a structure with open upper and lower ends; when assembling a semi-finished battery cell, first weld the lower cover plate 13 to the lower open end of the cylinder 11, then connect the positive and negative poles of the upper cover plate 12 to the positive and negative poles of the electrode assembly, then place the upper cover plate 12 and the electrode assembly as a whole into the cylinder 11 from the upper open end of the cylinder 11, and finally weld the upper cover plate 12 to the upper open end of the cylinder 11.

[0057] It should be emphasized that the outer shell of the battery cell is made of aluminum material, that is, the cylinder 11, the upper cover plate 12, and the lower cover plate 13 are all made of aluminum material.

[0058] Furthermore, the first sealing opening piece 5 and the second sealing opening piece 6 are both arranged on the upper cover plate 12 and the lower cover plate 13 in advance before assembling the battery cells.

[0059] The installation part of the heat transfer tube in the utility model has two forms:

[0060] Method 1: A through hole is opened on the pole, and the through hole is arranged perpendicular to the axial direction of the pole; the diameter of the through hole needs to ensure that the heat transfer tube can be tightly clamped therein, ensuring the installation stability while ensuring the heat transfer effect between the heat transfer tube and the pole.

[0061] Method 2: A groove is opened on the top or side wall of the pole; the width of the groove needs to ensure that the heat transfer tube is tightly clamped therein to ensure installation stability while ensuring the heat transfer effect between the heat transfer tube and the pole.

[0062] The processing of the groove is easier and the accuracy is easier to ensure. When the heat transfer tube is made of metal materials such as copper tubes or heat pipes, it is easier to ensure that the heat transfer tube is in close contact with the groove wall than the through hole (that is, the heat transfer tube can be squeezed into the groove from the groove opening through external tooling, and the two can be in close contact).

Claims

1. A battery cell, characterized in that: It includes a housing, a positive electrode column, a negative electrode column and an electrode assembly; The positive pole and the negative pole are insulated and fixed on the top of the shell; a part of the positive pole and the negative pole extends out of the shell, and a mounting portion for mounting a heat transfer tube is provided on the extended portion, and another part of the positive pole and the negative pole extends into the shell and is connected to the electrode assembly arranged in the shell; the shell contains an electrolyte; A first sealing opening piece is arranged on the top of the shell; and a second sealing opening piece is arranged on the bottom of the shell.

2. A battery cell according to claim 1, characterized in that: The first sealed package opening component and the second sealed package opening component are both dissolving mechanisms that can be dissolved in the electrolyte.

3. A battery cell according to claim 1, characterized in that: The first sealing and opening package component is a sealing mechanism that can be opened by external force, and the second sealing and opening package component is a dissolving mechanism that can be dissolved in the electrolyte.

4. A battery cell according to claim 1, characterized in that: The first sealing and opening package component is a dissolving mechanism that can be dissolved in the electrolyte, and the second sealing and opening package component is a sealing mechanism that can be opened by external force.

5. A battery cell according to any one of claims 2 to 4, characterized in that: The dissolving mechanism comprises an isolation layer arranged toward the inside of the shell and a dissolving layer arranged toward the outside of the shell and made of electrolyte additive material.

6. A battery cell according to claim 3 or 4, characterized in that: The sealing mechanism opened by external force is a magnet; the magnet comprises an iron sheet and a protective layer covering the outside of the iron sheet.

7. A battery cell according to claim 3 or 4, characterized in that: The portion of the outer shell corresponding to the sealing mechanism opened by external force is a weak area of ​​the outer shell.

8. A battery cell according to claim 1, characterized in that: The mounting portion is a groove or a through hole.

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