High-capacity cylindrical lithium-manganese battery

Abstract

The utility model discloses a high-capacity cylindrical lithium-manganese battery, and particularly relates to the technical field of lithium-manganese batteries, the high-capacity cylindrical lithium-manganese battery comprises a shell, a positive plate, a negative plate and a diaphragm are arranged in the shell, a positive assembly is arranged at an opening at the top end of the shell, and a strip-shaped PTC (Positive Temperature Coefficient) is arranged in the shell. An upper positive electrode current collector at the top and a lower positive electrode current collector at the bottom are arranged in the shell, and the strip-shaped PTC is clamped between the upper positive electrode current collector and the lower positive electrode current collector. According to the utility model, the gap is formed in the upper positive current collector and provides a space for the expansion of the strip-shaped PTC, so that the looseness of the upper positive current collector and the lower positive current collector caused by the expansion of the strip-shaped PTC can be effectively avoided, and the width of the gap is greater than that of the lower positive current collector, so that the lower positive current collector cannot be in direct contact with the upper positive current collector; therefore, the circuit of the battery can be kept in a cut-off state, and the phenomenon that the strip-shaped PTC is out of action and overdischarge continues to be generated is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium manganese batteries, and particularly relates to a high-capacity cylindrical lithium manganese battery. Background Art

[0002] The lithium manganese battery is also a manganese dioxide battery. The positive electrode is made of manganese dioxide, and the negative electrode is made of lithium. It has the characteristics of good low-rate and medium-rate discharge performance, low price, safety and practicality. Therefore, it has a very wide range of applications in the prior art.

[0003] In the actual use process, if the lithium manganese battery is not used correctly, it may cause over-discharge of the battery and lead to internal short circuit of the battery, and then the battery temperature rises, burns or even explodes. To avoid this problem, a PTC is provided in the lithium manganese battery in the prior art. The PTC expands at high temperature and can timely short-circuit the inside of the battery, thus avoiding danger, such as a new cylindrical lithium manganese battery with the publication number of CN203562472U.

[0004] However, since the PTC is sandwiched between the upper and lower positive current collectors, it may squeeze the positive current collector and cause it to loosen during the heat expansion process. And the upper positive current collector is directly above the lower positive current collector. Once the positive current collector loosens or the PTC falls off, the upper and lower positive current collectors may directly contact, resulting in the PTC losing its function and continuing to cause short circuit. Summary of the Utility Model

[0005] The purpose of the present utility model is to provide a high-capacity cylindrical lithium manganese battery. By providing a notch on the upper positive current collector, the notch provides space for the expansion of the strip-shaped PTC, which can effectively prevent the strip-shaped PTC from expanding and causing the lower positive current collector and the upper positive current collector to loosen.

[0006] To achieve the above purpose, the present utility model provides the following technical solution: A high-capacity cylindrical lithium manganese battery, including a housing. Inside the housing, there are a positive electrode sheet, a negative electrode sheet and a separator. At the opening at the top of the housing, there is a positive electrode assembly. Inside the housing, there is a strip-shaped PTC.

[0007] Inside the housing, there are an upper positive current collector at the top and a lower positive current collector at the bottom. The strip-shaped PTC is sandwiched between the upper positive current collector and the lower positive current collector. The strip-shaped PTC will expand after being heated, and the expanded strip-shaped PTC can cut off the circuit inside the battery. The bottom end of the lower positive current collector is connected to the positive electrode sheet, and the top end of the upper positive current collector is connected to the positive electrode assembly. A notch is provided on the upper positive current collector. The width of the lower positive current collector is smaller than the width of the notch, and the lower positive current collector is located directly below the notch.

[0008] Further, the positive electrode sheet and the negative electrode sheet are separated by a separator and wound into a cylindrical battery cell. A negative electrode current collector is fixedly provided at the bottom end inside the outer shell. The top end of the negative electrode current collector is connected to the negative electrode sheet, and the negative electrode current collector is located at the bottom of the cylindrical battery cell.

[0009] Further, the positive electrode assembly includes an explosion-proof film. A positive electrode cap is fixedly provided at the top end of the explosion-proof film, and the top end of the positive electrode cap extends to the top of the outer shell.

[0010] The bottom end of the explosion-proof film is fixedly provided with an explosion-proof film chassis, and the top end of the upper positive electrode current collector is connected to the bottom end of the explosion-proof film chassis.

[0011] Further, a sealing rubber ring is fixedly provided on the inner wall of the outer shell. The outer ends of the positive electrode cap and the explosion-proof film are clamped into the inside of the explosion-proof film chassis, and the outer end of the explosion-proof film chassis is connected to the sealing rubber ring. The opening end of the outer shell is sealed by the sealing rubber ring, the positive electrode cap, the explosion-proof film and the explosion-proof film chassis.

[0012] Further, a shielding assembly is provided at the top end of the positive electrode cap. The shielding assembly includes an insulating plate located at the top end of the positive electrode cap. An elastic rubber sheet is embedded on the insulating plate, and a sealing groove is formed on the rubber sheet. The protruding part of the positive electrode cap can pass through the rubber sheet through the sealing groove.

[0013] The bottom end of the insulating plate is fixedly provided with a corrugated pipe and a spring fixedly connected to the positive electrode cap. The spring is arranged inside the corrugated pipe, and the protruding part of the positive electrode cap is located inside the spring. The elastic force of the spring can control the position of the insulating plate.

[0014] Further, an insulating shell is fixedly provided at the outer end of the outer shell. A plurality of heat dissipation grooves for heat dissipation are formed on the inner wall of the insulating shell. The heat dissipation grooves make a heat dissipation gap exist between the outer end of the outer shell and the insulating shell, and a plurality of flat end faces are provided at the outer end of the insulating shell.

[0015] In the above technical solution, the technical effects and advantages provided by the present utility model are as follows: 1. By providing a notch on the upper positive electrode current collector, the notch provides space for the expansion of the strip-shaped PTC, and can effectively prevent the strip-shaped PTC from expanding and causing the lower positive electrode current collector and the upper positive electrode current collector to become loose.

[0016] 2. Since the width of the notch is greater than the width of the lower positive electrode current collector, even if the lower positive electrode current collector and the upper positive electrode current collector become loose, or the strip-shaped PTC falls off, the lower positive electrode current collector cannot directly contact the upper positive electrode current collector due to the existence of the notch. In this way, the circuit of the battery can be maintained in a cut-off state, and the over-discharge phenomenon caused by the strip-shaped PTC losing its function can be avoided. Description of the Drawings

[0017] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present utility model. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is a top view structure diagram of the present utility model.

[0019] Figure 2 It is a bottom view structure diagram of the present utility model.

[0020] Figure 3 It is the Figure 1 enlarged view of part A in the present utility model.

[0021] Figure 4 It is a cross-sectional view of the outer shell of the present utility model.

[0022] Figure 5 It is the Figure 4 enlarged view of part B in the present utility model.

[0023] Figure 6 It is a structural diagram of the positive electrode fluid of the present utility model.

[0024] Figure 7 It is a structural diagram of the interior of the shielding component of the present utility model.

[0025] Explanation of reference numerals: 1. Outer shell; 101. Positive electrode plate; 102. Negative electrode plate; 103. Separator; 2. Shielding component; 201. Insulating plate; 202. Bellows; 203. Spring; 204. Rubber sheet; 205. Sealing groove; 3. Insulating shell; 4. Flat end face; 5. Heat dissipation groove; 6. Negative electrode current collector; 7. Lower positive electrode current collector; 8. Strip-shaped PTC; 9. Upper positive electrode current collector; 10. Sealing rubber ring; 11. Positive electrode cap; 12. Explosion-proof film; 13. Explosion-proof film chassis; 14. Notch. Detailed implementation manners

[0026] To enable those skilled in the art to better understand the technical solutions of the present utility model, the following will further introduce the present utility model in detail in conjunction with the drawings.

[0027] The present utility model provides a high-capacity cylindrical lithium manganese battery as Figure 1-7 shown, including an outer shell 1. Inside the outer shell 1, there are a positive electrode plate 101, a negative electrode plate 102, and a separator 103. At the top opening of the outer shell 1, there is a positive electrode assembly, and inside the outer shell 1, there is a strip-shaped PTC 8.

[0028] Inside the housing 1, there are an upper positive current collector 9 at the top and a lower positive current collector 7 at the bottom. The strip-shaped PTC 8 is sandwiched between the upper positive current collector 9 and the lower positive current collector 7. The strip-shaped PTC 8 will expand when heated, and the expanded strip-shaped PTC 8 can cut off the circuit inside the battery. The bottom end of the lower positive current collector 7 is connected to the positive electrode plate 101, and the top end of the upper positive current collector 9 is connected to the positive electrode assembly. A notch 14 is formed on the upper positive current collector 9. The width of the lower positive current collector 7 is smaller than the width of the notch 14, and the lower positive current collector 7 is located directly below the notch 14.

[0029] A strip-shaped PTC 8 is arranged between the lower positive current collector 7 and the upper positive current collector 9. When over-discharge occurs inside the battery, the positive electrode plate 101 and the negative electrode plate 102 inside the housing 1 will heat up. After the strip-shaped PTC 8 senses the temperature rise, it will expand. The resistance of the expanded strip-shaped PTC 8 will increase sharply, causing the circuit inside the battery to break, thereby avoiding further heating of the battery and preventing the battery from catching fire or exploding. Since a notch 14 is formed on the upper positive current collector 9, the notch 14 provides space for the expansion of the strip-shaped PTC 8, effectively preventing the strip-shaped PTC 8 from expanding and causing the lower positive current collector 7 and the upper positive current collector 9 to become loose. Moreover, the width of the notch 14 is greater than the width of the lower positive current collector 7. Even if the lower positive current collector 7 and the upper positive current collector 9 become loose, or the strip-shaped PTC 8 falls off, the lower positive current collector 7 will not be able to directly contact the upper positive current collector 9 due to the existence of the notch 14, thus maintaining the circuit of the battery in a cut-off state and preventing the strip-shaped PTC 8 from losing its function and continuing to cause over-discharge.

[0030] To further improve the safety of the battery, as Figure 4 shown, the positive electrode plate 101 and the negative electrode plate 102 are separated by a separator 103 and wound into a cylindrical battery core. A negative current collector 6 is fixedly arranged at the bottom end inside the housing 1. The top end of the negative current collector 6 is connected to the negative electrode plate 102, and the negative current collector 6 is located at the bottom of the cylindrical battery core.

[0031] The positive electrode assembly includes an explosion-proof film 12. The top end of the explosion-proof film 12 is fixedly provided with a positive electrode cap 11, and the top end of the positive electrode cap 11 extends to the top of the housing 1.

[0032] The bottom end of the explosion-proof film 12 is fixedly provided with an explosion-proof film chassis 13, and the top end of the upper positive current collector 9 is connected to the bottom end of the explosion-proof film chassis 13.

[0033] A sealing rubber ring 10 is fixedly arranged on the inner wall of the housing 1. The outer ends of the positive electrode cap 11 and the explosion-proof film 12 are clamped into the interior of the explosion-proof film chassis 13. The outer end of the explosion-proof film chassis 13 is connected to the sealing rubber ring 10. The opening end of the housing 1 is sealed by the sealing rubber ring 10, the positive electrode cap 11, the explosion-proof film 12 and the explosion-proof film chassis 13.

[0034] When the temperature inside the housing 1 rises sharply due to over-discharge, the pressure inside the housing 1 will also increase rapidly. When the air pressure exceeds the set value, the explosion-proof film 12 will crack, so that the expanded gas is discharged outward through the crack, thereby releasing the pressure inside the housing 1 and avoiding explosion.

[0035] In the idle state, it is necessary to protect the positive electrode cap 11 and reduce the wear of the positive electrode cap 11. As shown in, Figure 4 、 7 a shielding assembly 2 is arranged at the top of the positive electrode cap 11. The shielding assembly 2 includes an insulating plate 201 located at the top of the positive electrode cap 11. An elastic rubber sheet 204 is inlaid on the insulating plate 201. A sealing groove 205 is formed on the rubber sheet 204. The protruding part of the positive electrode cap 11 can pass through the rubber sheet 204 through the sealing groove 205.

[0036] A corrugated pipe 202 and a spring 203 fixedly connected to the positive electrode cap 11 are fixedly arranged at the bottom end of the insulating plate 201. The spring 203 is arranged inside the corrugated pipe 202. The protruding part of the positive electrode cap 11 is located inside the spring 203. The elastic force of the spring 203 can control the position of the insulating plate 201.

[0037] In the idle state, the elastic force of the spring 203 pushes the insulating plate 201 upward, so that the insulating plate 201 is located at the top of the positive electrode cap 11. In this way, the protruding part of the positive electrode cap 11 is wrapped by the shielding assembly 2. Therefore, during idle time, the oxidation and wear of the positive electrode cap 11 are reduced. When the battery needs to be used, press the insulating plate 201 downward. The insulating plate 201 moves downward accordingly, and the corrugated pipe 202 and the spring 203 are compressed accordingly. The positive electrode cap 11 passes through the rubber sheet 204 through the sealing groove 205, and the positive electrode cap 11 is exposed for use.

[0038] To improve the stability of the battery, as shown in, Figure 1 、 2 、3, an insulating shell 3 is fixedly arranged at the outer end of the housing 1. A plurality of heat dissipation grooves 5 for heat dissipation are formed on the inner wall of the insulating shell 3. The heat dissipation grooves 5 make there be a heat dissipation gap between the outer end of the housing 1 and the insulating shell 3. A plurality of flat end faces 4 are arranged at the outer end of the insulating shell 3.

[0039] An insulating shell 3 is wrapped around the outer end of the outer shell 1, which can play a certain protective role for the outer shell 1. Moreover, heat dissipation grooves 5 are provided on the flat end face 4. The heat dissipation grooves 5 are located between the insulating shell 3 and the outer shell 1, providing space for the heat dissipation of the outer shell 1. And a flat end face 4 with a flat surface is ground on the originally arc-shaped outer vertical surface of the insulating shell 3. When the battery is laid down, the flat end face 4 can limit the rolling of the insulating shell 3, thereby improving the stability of the battery.

[0040] Only some exemplary embodiments of the present invention have been described by way of illustration above. Without doubt, for those of ordinary skill in the art, the described embodiments can be modified in various different ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A high-capacity cylindrical lithium manganese battery, comprising a housing (1), inside which there are provided a positive electrode plate (101), a negative electrode plate (102) and a separator (103), and at the open top of the housing (1) there is provided a positive electrode assembly, characterized in that: Inside the said housing (1), there is a strip-shaped PTC (8); inside the housing (1), there are an upper positive current collector (9) at the top and a lower positive current collector (7) at the bottom. The strip-shaped PTC (8) is sandwiched between the upper positive current collector (9) and the lower positive current collector (7). The bottom end of the lower positive current collector (7) is connected to the positive electrode plate (101), the top end of the upper positive current collector (9) is connected to the positive electrode assembly. There is a notch (14) on the upper positive current collector (9). The width of the lower positive current collector (7) is smaller than the width of the notch (14) and the lower positive current collector (7) is located directly below the notch (14).

2. A high-capacity cylindrical lithium manganese battery according to claim 1, characterized in that: The positive electrode plate (101) and the negative electrode plate (102) are separated by a separator (103) and wound into a cylindrical battery cell. At the bottom end inside the housing (1), there is a fixed negative current collector (6). The top end of the negative current collector (6) is connected to the negative electrode plate (102). The negative current collector (6) is located at the bottom of the cylindrical battery cell.

3. A high-capacity cylindrical lithium manganese battery according to claim 1, characterized in that: The positive electrode assembly includes an explosion-proof film (12). At the top end of the explosion-proof film (12), there is a fixed positive electrode cap (11). The top end of the positive electrode cap (11) extends to the top of the housing (1). At the bottom end of the explosion-proof film (12), there is a fixed explosion-proof film chassis (13). The top end of the upper positive current collector (9) is connected to the bottom end of the explosion-proof film chassis (13).

4. A high-capacity cylindrical lithium manganese battery according to claim 3, characterized in that: On the inner wall of the housing (1), there is a fixed sealing rubber ring (10). The outer ends of the positive electrode cap (11) and the explosion-proof film (12) are snapped into the inside of the explosion-proof film chassis (13). The outer end of the explosion-proof film chassis (13) is connected to the sealing rubber ring (10).

5. A high-capacity cylindrical lithium manganese battery according to claim 3, characterized in that: At the top end of the positive electrode cap (11), there is a shielding assembly (2). The shielding assembly (2) includes an insulating plate (201) at the top end of the positive electrode cap (11). An elastic rubber sheet (204) is inlaid on the insulating plate (201). There is a sealing groove (205) on the rubber sheet (204). At the bottom end of the insulating plate (201), there are a corrugated pipe (202) and a spring (203) fixedly connected to the positive electrode cap (11). The spring (203) is arranged inside the corrugated pipe (202). The protruding part of the positive electrode cap (11) is located inside the spring (203).

6. A high-capacity cylindrical lithium manganese battery according to claim 1, characterized in that: On the outer end of the housing (1), there is a fixed insulating shell (3). On the inner wall of the insulating shell (3), there are a plurality of heat dissipation grooves (5) for heat dissipation. On the outer end of the insulating shell (3), there are a plurality of flat end faces (4).

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