Cylindrical lithium battery capable of being simply packaged

Abstract

The utility model discloses a cylindrical lithium battery capable of being simply packaged, which relates to the field of lithium battery preparation and comprises a positive electrode combined cap, a winding battery cell and a battery shell, the winding battery cell is arranged in the battery shell, a positive electrode of the winding battery cell is connected with the positive electrode combined cap, and a negative electrode of the winding battery cell is connected with the battery shell. And the battery shell and the positive electrode combined cap are sealed in a mechanical pressing manner. Compared with the prior art, the utility model has the advantages that: (1) the packaging process is simplified, and the production efficiency is improved; (2) the sealing performance of the battery is ensured, and the risk of electrolyte leakage is reduced; (3) the battery is simple in structure and easy to realize automatic mass production; (4) the safety and the reliability of the battery are improved; and (5) the production cost is reduced, and the market competitiveness is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of lithium battery preparation, specifically to a cylindrical lithium battery of simple and easy packaging. BACKGROUND

[0002] In the field of lithium battery preparation, cylindrical lithium batteries are widely used in various portable devices and energy storage systems due to their high energy density, long cycle life, and good safety. In the traditional preparation process of cylindrical lithium batteries, the battery cell and the electronic functional board, such as the protection board, are usually processed separately. After the battery cell is processed, a secondary PACK assembly is performed to connect the battery cell and the electronic functional board. This preparation method not only increases the production process, reduces the production efficiency, but also increases the production cost.

[0003] Currently, some patents have attempted to solve this problem. For example, patent CN201520275458.8 proposes a lithium battery with an integrated positive electrode structure, which integrates the battery cell and electronic components together. However, the packaging process is still relatively complex, and the sealed battery still needs to be improved in terms of sealing and stability.

[0004] In addition, the existing cylindrical lithium battery has the following shortcomings in the packaging process: (1) complex packaging process, low production efficiency; (2) poor sealing of the packaged battery, with the risk of electrolyte leakage; (3) complex battery structure, not conducive to automated mass production. UTILITY MODEL CONTENT

[0005] To solve the problems in the prior art, the utility model provides a cylindrical lithium battery that can be simply packaged. The utility model aims to optimize the battery structure, realize the integrated packaging of the battery cell and the electronic functional board, simplify the packaging process, improve the production efficiency, and ensure the sealing and stability of the battery.

[0006] To solve the above technical problems, the utility model provides a technical scheme: a cylindrical lithium battery that can be simply packaged, including a positive electrode combined cap, a wound battery cell, and a battery shell. The wound battery cell is arranged in the battery shell, the positive electrode of the wound battery cell is connected with the positive electrode combined cap, and the negative electrode of the wound battery cell is connected with the battery shell. After the battery is filled with liquid, the battery shell and the positive electrode combined cap are sealed by mechanical pressing.

[0007] The battery shell is a nickel-plated steel shell, and one end of the battery shell is mechanically processed with a groove during battery production. The groove is used to fix the relative position of the wound battery cell in the battery shell to support the positive electrode combined cap.

[0008] The positive electrode combined cap is composed of an electronic functional board, an aluminum bowl, and a sealing ring. The aluminum bowl is assembled in the sealing ring, and the electronic functional board is fastened on top of the aluminum bowl in the sealing ring.

[0009] The electronic function board is composed of a positive current collecting cap, a negative ring-shaped pad, a gas vent, a positive ring-shaped pad, and a PCB board. A positive current collecting cap is arranged at the center of the front surface of the PCB board as a positive electrode for inputting or outputting the current of the battery. A negative ring-shaped pad with a width of 0.5-2 mm is arranged around the front surface of the PCB board, and is used for welding with the negative electrode of the battery shell. A positive ring-shaped pad with a width of 0.5-2 mm is arranged around the back surface of the PCB board, and is used for connecting after being pressed with the aluminum small bowl to realize the positive electrode current lead of the battery. One or more gas vents with a diameter of 0.1-1 mm are arranged on the electronic function board, and the gas vent is used to discharge the gas in the battery when the battery is in thermal runaway, so as to avoid the risk of explosion of the battery.

[0010] One or two positive electrode ears are led out from the positive electrode of the wound battery cell, and the positive electrode ear is welded with the aluminum small bowl by laser or ultrasonic welding. One or two negative electrode ears are led out from the negative electrode of the wound battery cell, and the negative electrode ear is resistance-welded with the bottom of the battery shell.

[0011] Further, the wall thickness of the battery shell is selected to be 0.15-0.5 mm.

[0012] Further, the aluminum small bowl is a small bowl-shaped structure formed by stamping an aluminum plate, and the annular platform of the aluminum small bowl has a thickness of 0.3-1.5 mm and a width of 0.5-2.5 mm. The aluminum small bowl is provided with a pressure relief valve at the bottom, and the pressure relief valve adopts a cross or circular ring structure. The pressure relief pressure of the pressure relief valve is set to 0.1-5 MPa.

[0013] Further, the sealing ring is made of one of PP, PE or PEFT, and a ring or two rings of circular bosses are arranged at the middle part of the contact surface between the lower edge of the sealing ring and the annular platform of the aluminum small bowl. The height of the circular boss is 0.1-0.5 mm, and the circular boss is used to improve the combination tightness of the aluminum small bowl and the sealing ring, and prevent the electrolyte from leaking out of the gap.

[0014] Further, the upper edge of the sealing ring is provided with an inward boss with a thickness of 0.2-0.8 mm, and the boss is used to hold the aluminum small bowl and the electronic function board.

[0015] Further, the electronic function board is composed of several electrical elements such as a PCB board, a functional IC chip, a chip capacitor, a chip resistor, a chip LED, a chip inductor, a MOS tube, a positive current collecting cap or a current collecting nail, and the electronic function board has the functions of protection, voltage reduction or voltage increase for the battery. The surface of the electronic function board is treated with three-proofing.

[0016] Further, the positive current collecting cap can be replaced with a positive current collecting nail for assembly.

[0017] Further, the inner wall of the battery shell and the sealing ring of the positive electrode combined cover cap are in interference fit, and the sealing ring is pressed on the rolling groove of the battery shell.

[0018] Further, the battery shell and the positive electrode combined cap are mechanically pressed to deform the mouth of the battery shell and realize battery sealing.

[0019] Further, the sealing ring is used to realize sealing and isolation of the positive and negative electrodes of the battery, and the sealed battery product has a sealing test pressure of ≥0.6 MPa in a free state.

[0020] Compared with the prior art, the utility model has the advantages that: (1) the packaging process is simplified, and the production efficiency is improved; (2) the sealing property of the battery is ensured, and the risk of electrolyte leakage is reduced; (3) the battery structure is simple, and automation mass production is easy to realize; (4) the safety and reliability of the battery are improved; (5) the production cost is reduced, and the market competitiveness is improved. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a cross-sectional structure schematic view of the utility model.

[0022] Figure 2 is an explosion view of the utility model.

[0023] Figure 3 is an external structure schematic view of the positive electrode combined cap.

[0024] Figure 4 is an explosion view of the positive electrode combined cap.

[0025] As shown in the figure: 1, the positive electrode combined cap, 11, the electronic function board, 111, the positive electrode current collecting cap, 112, the negative electrode annular pad, 113, the air vent, 114, the positive electrode annular pad, 115, the PCB board, 12, the aluminum small bowl, 121, the explosion-proof valve, 13, the sealing ring, 131, the circular boss, 2, the wound battery core, 21, the positive electrode lug, 22, the negative electrode lug, 3, the battery shell. DETAILED DESCRIPTION

[0026] The utility model will be further described in detail in combination with the drawings.

[0027] Example one

[0028] As shown in Figure 1 , Figure 2 , Figure 3 and Figure 4 , the core components of the device include:

[0029] (1) the positive electrode combined cap 1

[0030] The positive electrode combined cover cap 1 is composed of three parts: an electronic function board 11, an aluminum small bowl 12, and a sealing ring 13. The electronic function board 11 is a PCB board 115 that integrates positive electrode current collector caps 111, negative electrode ring pads 112, air vent holes 113, positive electrode ring pads 114, and other functional areas. The aluminum small bowl 12 is a small bowl-shaped structure formed by stamping, with a pressure relief valve 121 in the center of the bottom. The sealing ring 13 is located between the aluminum small bowl 12 and the battery shell 3, used for sealing.

[0031] The electronic function board 11 is responsible for the functions of current input / output, protection, voltage reduction / boosting, etc. of the battery, while providing a negative electrode welding surface with the battery shell 3. The aluminum small bowl 12 serves as a positive electrode current collector and is welded with the positive electrode tab 21 of the battery cell. The pressure relief valve 121 releases gas when the internal pressure of the battery is abnormal, preventing the battery from exploding. The sealing ring 13 ensures the sealing of the battery interior. The aluminum small bowl 12 is assembled inside the sealing ring 13, and the electronic function board 11 is buckled on top of the aluminum small bowl 12 inside the sealing ring 13, fixed by mechanical compression.

[0032] (2) Wound battery cell 2

[0033] The wound battery cell 2 is composed of positive electrode material, negative electrode material, separator, and electrolyte, in a cylindrical shape, with positive and negative electrodes leading out positive electrode tab 21 and negative electrode tab 22 respectively. The wound battery cell 2 is the energy storage unit of the battery, generating electrical energy through chemical reactions between the positive and negative electrodes. The positive electrode tab 21 is connected to the aluminum small bowl 12 through laser or ultrasonic welding, and the negative electrode tab 22 is connected to the bottom of the battery shell 3 through resistance welding.

[0034] (3) Battery shell 3

[0035] The battery shell 3 is a nickel-plated steel shell with a rolling groove at one end, used to fix the wound battery cell 2 and support the positive electrode combined cover cap 1. The battery shell 3 serves as the external protective structure of the battery, providing mechanical strength and safety. The rolling groove is used for positioning and fixing the battery cell, and also serves as the stress point during mechanical compression. The battery shell 3 and the positive electrode combined cover cap 1 are sealed by mechanical compression, and the mouth of the battery shell 3 deforms and closes during the compression process, contacting the negative electrode ring pad 112 of the electronic function board 11 and being welded by soldering.

[0036] Example Two

[0037] As shown in Figure 1 , Figure 2 , Figure 3 and Figure 4 , the working mode of the device is as follows:

[0038] (1) Assembly: First, the wound cell 2 is placed into the battery case 3, and the negative tab 22 is welded to the bottom of the battery case 3. Then, the opening end of the case 3 is grooved. Next, the sealing ring 13 and the aluminum bowl 12 are assembled together, and the positive tab 21 is welded to the aluminum bowl 12. Finally, the electronic functional board 11 is buckled into the sealing ring 13, forming the positive combined cap 1.

[0039] (2) Liquid injection and sealing: After injecting electrolyte into the battery case 3, the positive combined cap 1 is installed at the opening end of the battery case 3. Through mechanical pressing equipment, the opening end of the battery case 3 is pressed to deform and close, and at the same time, the sealing ring 13 is tightly pressed on the grooved case 3, realizing the sealing of the battery.

[0040] (3) Welding and testing: During the pressing process, the opening end of the battery case 3 deforms and closes after contacting the negative ring-shaped pad 112 of the electronic functional board 11, and the two are connected together by soldering. Finally, the performance and sealing of the battery are tested to ensure the quality and safety of the battery.

[0041] (4) Use: During normal use, the battery is connected to the external circuit through the positive current collecting cap 111 or current collecting pin, realizing the output of electric energy. When the internal pressure of the battery is abnormal, the explosion-proof valve 121 will automatically open to release the internal gas and prevent the battery from exploding.

[0042] Example Three

[0043] As shown in Figure 1 , Figure 2 , Figure 3 and Figure 4 , the working principle of the device is that the wound cell 2 serves as the energy storage unit of the battery, and the positive and negative materials inside it exchange ions through the electrolyte to generate electric energy. The positive combined cap 1 serves as the positive output end of the battery and is connected to the positive tab 21 of the wound cell 2 through laser or ultrasonic welding, ensuring effective transmission of current. The negative tab 22 is connected to the bottom of the battery case 3 through resistance welding, forming the negative electrode of the battery.

[0044] The battery case 3 not only provides mechanical support and protection for the battery, but also serves as the negative electrode conductor of the battery. Through mechanical pressing, the sealing ring 13 between the battery case 3 and the positive combined cap 1 is tightly pressed, forming a sealed structure to prevent electrolyte leakage. At the same time, the opening end of the battery case 3 deforms and closes during the pressing process, contacting the negative ring-shaped pad 112 on the electronic functional board 11 and being further welded by soldering, further enhancing the sealing and conductivity of the battery.

[0045] The electronic function board 11 integrates the functions of battery protection, voltage reduction or increase, etc. It is realized by functional IC chips, patch capacitors, patch resistors and other elements on the PCB board 115. When the battery is working, the electronic function board 11 monitors the voltage, current and other parameters of the battery to ensure that the battery operates within a safe range. If the battery has abnormal conditions such as overcharging, overdischarging or high temperature, the electronic function board 11 will automatically cut off the circuit to protect the battery from damage.

[0046] In addition, the air vent 113 on the positive electrode combined cap 1 can quickly discharge the high-pressure gas inside the battery when the battery has a thermal runaway, avoiding the risk of battery explosion.

[0047] Example Four

[0048] As shown in Figure 1 , Figure 2 , Figure 3 and Figure 4 , the device can be implemented according to the following steps:

[0049] (1) Prepare materials: First, prepare the materials needed for the winding cell 2, the battery shell 3, the positive electrode combined cap 1 and its components, the electronic function board 11, the aluminum small bowl 12, the sealing ring 13, etc.

[0050] (2) Cell assembly: Place the winding cell 2 into the battery shell 3, ensuring that the positive and negative electrode tabs 21, 22 of the cell extend out of the designated positions of the shell.

[0051] (3) Positive electrode combined cap assembly: Assemble the aluminum small bowl 12 inside the sealing ring 13, ensuring that the explosion-proof valve 121 faces the inside of the battery. Then, attach the electronic function board 11 to the sealing ring 13, ensuring that the positive electrode annular pad 114 is in close contact with the aluminum small bowl 12.

[0052] (4) Welding: Use laser or ultrasonic welding equipment to weld the positive electrode tab 21 and the aluminum small bowl 12 together. At the same time, use resistance welding equipment to weld the negative electrode tab 22 and the bottom of the battery shell 3.

[0053] (5) Liquid injection and sealing: After injecting an appropriate amount of electrolyte into the battery shell 3, install the positive electrode combined cap 1 at the open end of the battery shell 3. Use a mechanical pressing device to press the mouth of the battery shell 3, causing the mouth to deform and close, while ensuring that the sealing ring 13 is tightly pressed onto the rolling groove of the battery shell 3, forming a sealed structure.

[0054] (6) Welding of the negative electrode: During the pressing process, the mouth of the battery shell 3 deforms and closes after contacting the negative electrode annular pad 112 of the electronic function board 11, and the two are connected together by soldering, further enhancing the sealing and conductivity of the battery.

[0055] (7) Test and quality inspection: the assembled battery is tested for performance and sealing to ensure that the quality and safety of the battery meet the design requirements.

[0056] (8) Packaging and delivery: the battery that passes the test is packaged, and product manuals and warranty cards and other documents are attached, ready for delivery and sale.

[0057] The above shows and describes the basic principle and main features of the utility model and the advantages of the utility model, and the skilled person in the art should understand that the utility model is not limited by the above examples, and the above examples and descriptions in the specification are only to illustrate the principle of the utility model, and various changes and improvements can be made to the utility model without departing from the spirit and scope of the utility model, and these changes and improvements all fall within the scope of the utility model claimed. The scope of protection of the utility model is defined by the appended claims and their equivalents.

Claims

1. A cylindrical lithium battery which can be easily packaged, comprising a positive electrode combined cap (1), a wound cell (2), and a battery case (3), characterized in that: The winding cell (2) is arranged in the battery shell (3), the positive electrode of the winding cell (2) is connected with the positive electrode combined cover cap (1), the negative electrode of the winding cell (2) is connected with the battery shell (3), and the battery shell (3) and the positive electrode combined cover cap (1) are sealed by mechanical pressing after the battery is injected with liquid; The battery shell (3) is a nickel-plated steel shell, one end of the battery shell (3) is mechanically processed with a rolling groove during the battery production process, the rolling groove is used to fix the relative position of the winding cell (2) in the battery shell (3) to support the positive electrode combined cover cap (1). The positive electrode combined cover cap (1) is composed of an electronic function plate (11), an aluminum small bowl (12) and a sealing ring (13), the aluminum small bowl (12) is assembled in the sealing ring (13), and the electronic function plate (11) is buckled on the upper surface of the aluminum small bowl (12) in the sealing ring (13). The electronic function plate (11) is composed of a positive electrode current collecting cap (111), a negative electrode annular pad (112), a gas vent (113), a positive electrode annular pad (114) and a PCB plate (115), the positive electrode current collecting cap (111) is arranged at the center of the front surface of the PCB plate (115) as the positive electrode of the battery current input or output, the negative electrode annular pad (112) with a width of 0.5-2 mm is arranged around the front surface of the PCB plate (115) and is used for welding with the negative electrode of the battery shell (3), the positive electrode annular pad (114) with a width of 0.5-2 mm is arranged around the back surface of the PCB plate (115) and is used for connecting after pressing with the aluminum small bowl (12) to realize the battery positive electrode drainage, one or more gas vents (113) with a diameter of 0.1-1 mm are arranged on the electronic function plate (11), the gas vent (113) is used for discharging the battery internal gas when the battery is in thermal runaway to avoid the risk of battery explosion. The winding cell (2) is arranged in the battery shell (3), the positive electrode of the winding cell (2) is connected with the positive electrode combined cover cap (1), the negative electrode of the winding cell (2) is connected with the battery shell (3), and the battery shell (3) and the positive electrode combined cover cap (1) are sealed by mechanical pressing after the battery is injected with liquid; 2. The cylindrical lithium battery of simple packaging according to claim 1, characterized in that: The wall thickness of the battery shell (3) is selected to be 0.15-0.5 mm.

3. The cylindrical lithium battery of claim 1, wherein: The aluminum small bowl (12) is a small bowl-shaped structure formed by stamping an aluminum plate, the annular platform of the aluminum small bowl (12) has a thickness of 0.3-1.5 mm and a width of 0.5-2.5 mm, the bottom of the aluminum small bowl (12) is provided with a pressure relief valve (121), the pressure relief valve (121) adopts a cross or circular ring structure, and the pressure relief pressure of the pressure relief valve (121) is set to 0.1-5 MPa.

4. The cylindrical lithium battery of claim 1, wherein: The sealing ring (13) is made of one of PP, PE or PEFT, and a ring or two rings of circular bosses (131) are arranged at the middle part of the contact surface between the sealing ring (13) and the annular platform of the aluminum small bowl (12), the height of the circular boss (131) is 0.1-0.5 mm, and the circular boss (131) is used to improve the combination tightness of the aluminum small bowl and the sealing ring (13) to prevent the electrolyte from leaking out of the gap.

5. The cylindrical lithium battery of claim 1, wherein: The upper edge of the sealing ring (13) is provided with an inward boss, the boss thickness is 0.2-0.8mm, and the boss is used for buckling the aluminum bowl (12) and the electronic function board (11).

6. The cylindrical lithium battery of simple packaging according to claim 1, characterized in that: The electronic function board (11) is composed of several electrical elements such as PCB board (115), functional IC chip, patch capacitor, patch resistor, patch LED, patch inductor, MOS tube, positive current collecting cap (111) or current collecting nail, and the electronic function board (11) has the functions of protecting, reducing or increasing the voltage of the battery; the surface of the electronic function board (11) is treated by three-proofing.

7. The cylindrical lithium battery of claim 1, wherein: The positive current collecting cap (111) can be replaced by the positive current collecting nail for assembly.

8. The cylindrical lithium battery of claim 1, wherein: The inner wall of the battery shell (3) and the sealing ring (13) of the positive electrode combined cover cap (1) are in interference fit, and the sealing ring (13) is pressed on the rolling groove of the battery shell (3).

9. The cylindrical lithium battery of claim 1, wherein: The battery shell (3) and the positive electrode combined cover cap (1) are mechanically pressed to make the mouth of the battery shell (3) deform and close, realize the sealing of the battery, and the upper edge of the battery shell (3) after closing is in contact with the negative ring-shaped pad (112) on the electronic function board (11) and is welded by soldering.

10. The cylindrical lithium battery of simple packaging according to claim 1, wherein: The sealing ring (13) is used to realize sealing and isolation of the positive and negative electrodes of the battery, and the sealed battery product is free in state, and the sealing test pressure is greater than or equal to 0.6MPa.

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