An anti-seepage liquid columnar battery

Abstract

The present invention provides a leak-proof liquid columnar battery, which includes a columnar battery housing. The battery housing has an inner cavity, and a columnar fitting is provided at the bottom of the inner cavity. The columnar fitting divides the inner cavity into two mutually independent and sealed sub-cavities. One of the sub-cavities is filled with a battery cell as a battery cell installation cavity, and the other sub-cavity is used as a spare cavity. A first pressure relief valve is provided at the top of the battery housing. When the first pressure relief valve is opened, it communicates the battery cell installation cavity with the outside; a second pressure relief valve is provided on the columnar fitting. When the second pressure relief valve is opened, it communicates the spare cavity with the battery cell installation cavity; the pressure relief threshold of the second pressure relief valve < the pressure relief threshold of the first pressure relief valve. The leak-proof liquid columnar battery of the present invention can improve the problem of liquid leakage during pressure relief of the battery, and moreover, can also solve the problems of high production cost, low efficiency, and inability to quickly meet customized requirements of differential batteries in the prior art.

Description

Technical Field

[0001] The present invention relates to the field of batteries, and particularly to a liquid-proof cylindrical battery. Background Art

[0002] Existing cylindrical batteries usually only have an explosion-proof structure at the sealing component. When the battery is in normal use, misused, or over-discharged, the substances inside the battery generate gas, resulting in an increase in the internal pressure. When the internal pressure of the battery exceeds the pressure resistance value of the explosion-proof structure, the explosion-proof structure will rupture and the contents will overflow. The overflow mainly is the electrolyte inside the battery. When the electrolyte is a strong alkaline substance such as high-concentration potassium hydroxide, the overflow will corrode the battery compartment and skin. When the electrolyte is an organic electrolyte, it contains toxic substances, which not only corrode and pollute the external environment but also cause serious harm to the human body. The patent with the authorization announcement number CN101694881B discloses a safe cylindrical lithium-manganese dioxide battery, including a cylindrical battery case. The center position of the top wall of the battery case protrudes outward to form a positive terminal. An air chamber communicating with the inner cavity of the battery case is formed inside the positive terminal. A self-activating explosion-proof pressure relief device is provided at the top of the battery case. The self-activating explosion-proof pressure relief device includes an annular deformation groove formed by the inward depression of the top wall of the battery case. The bottom of the deformation groove is a weak part. The bottom of the battery case is connected with a sealing component, and the sealing component includes a sealing insulating plastic. When the air pressure inside the battery and in the air chamber is too high and the temperature is too high, while the weak part of the deformation groove is pressed and ruptured, the sealing insulating plastic melts to form a pressure relief hole, realizing simultaneous pressure relief at both ends of the battery and avoiding the possibility of battery explosion. Although the above patent has good instantaneous pressure relief and explosion-proof capabilities, the rupture of the two pressure relief valves will cause the electrolytes inside the battery to spray out instantaneously from both ends of the battery at the same time, and the scope of corrosion and pollution is instead larger and wider.

[0003] Moreover, existing cylindrical batteries also have the following defects: Currently, the performance of batteries generally can meet the needs of customers for high-performance batteries. However, there are differences in the performance requirements of batteries in different usage scenarios, and there are also differences in the performance and price requirements of different customers for batteries. Therefore, batteries of the same model need multiple batteries with different performance and price differences (performance differences lead to price differences) to meet the different needs of customers respectively. Since the performance differences of batteries are mainly achieved by differences in formulations, materials, etc. The battery formulations and materials corresponding to different battery performances require a long time to be verified from research to application, which is time-consuming, laborious, has a high R & D cost, and low efficiency. And when the customized needs of customers exceed the multiple differentiated products in the original reserve, new differentiated products need to be developed again, and the customized needs cannot be quickly met. Summary of the Invention

[0004] The present invention aims to provide a leak-proof liquid cylindrical battery, which can improve the problem of liquid leakage during pressure relief of the battery. Moreover, it can also solve the problems of high production cost, low efficiency, and inability to quickly meet customized requirements existing in the prior art.

[0005] A leak-proof liquid cylindrical battery, comprising a cylindrical battery housing, the battery housing having an inner cavity, a cylindrical fitting provided at the bottom of the inner cavity, the cylindrical fitting dividing the inner cavity into two mutually independent and sealed sub-cavities, one of the sub-cavities containing a battery cell as a battery cell installation cavity, and the other sub-cavity serving as a spare cavity. A first pressure relief valve is provided at the top of the battery housing, and when the first pressure relief valve is opened, it communicates the battery cell installation cavity with the outside; a second pressure relief valve is provided on the cylindrical fitting, and when the second pressure relief valve is opened, it communicates the spare cavity with the battery cell installation cavity; the pressure relief threshold of the second pressure relief valve < the pressure relief threshold of the first pressure relief valve.

[0006] The leak-proof liquid cylindrical battery of the present invention has the following technical effects:

[0007] (1) By adding the cylindrical fitting in the inner cavity of the battery housing, the purpose of reducing the accommodation space of the battery cell can be achieved through the cylindrical fitting. The battery cell is usually composed of positive and negative electrode materials and a separator. By controlling the volume of the cylindrical fitting, the inner cavity space of the battery can be reasonably allocated, the amount of the positive and negative materials of the battery can be flexibly controlled, and the purpose of differentiating the battery capacity can be achieved by the different reduction amounts of the positive and negative electrode materials of the battery. Based on the existing mature product solutions (without adjusting the original battery formula and materials), the performance of the battery can be controlled and adjusted, which is beneficial to quickly meet the customized requirements of customers, with simple processes, short battery verification cycles, low costs, and high efficiency;

[0008] (2) The internal space of the battery is reasonably and compactly allocated, and problems such as low utilization rate of battery performance, large degradation rate, and poor anti-vibration and drop performance caused by too large accommodation space of the battery cell will not occur;

[0009] (3) Meanwhile, in the present invention, the cylindrical fitting is provided to divide the inner cavity into two independent and sealed battery cell installation cavities and a spare cavity. The cylindrical fitting is provided with a second pressure relief valve, and when the second pressure relief valve is opened, it can communicate the spare cavity with the battery cell installation cavity. During the normal use of the battery, the gas production inside the battery will gradually increase. The main reasons are as follows: The reactive substances inside the battery are corroded to generate gas. For example, when an alkaline battery is short-circuited or over-discharged, the negative reactive substance inside the battery becomes more active, and the negative reactive substance is likely to react with the electrolyte to generate gas substances; when an alkaline battery is misused, electrolysis of water occurs inside the battery during the charging process, generating hydrogen and oxygen. The gas production inside the battery will first cause the pressure in the battery cell installation cavity to increase. When the pressure in the battery cell installation cavity is greater than the pressure relief threshold of the second pressure relief valve, the second pressure relief valve opens for pressure relief. The spare cavity comes into play, and the gas in the battery cell installation cavity enters the spare cavity, so that the pressure in the battery cell installation cavity is relieved. And under the action of the pressure difference, most of the free electrolyte in the battery cell installation cavity will also flow into the spare cavity together with the gas, and the amount of electrolyte in contact with the battery cell decreases, which is beneficial to reducing the gas production reaction inside the battery; as the internal reaction of the battery continues, the gas volume in the battery cell installation cavity and the spare cavity continues to increase, and the pressure rises again. When it rises to be greater than the pressure relief threshold of the first pressure relief valve, the first pressure relief valve opens for pressure relief. However, since the free electrolyte inside the battery has flowed into the spare cavity, the liquid flowing out of the battery will be greatly reduced, which can effectively improve the leakage phenomenon and the pollution caused by the leakage;

[0010] (4) The spare cavity brought by the cylindrical fitting of the present invention expands the gas storage space inside the battery, thereby improving the leak-proof liquid ability of the battery;

[0011] (5) If the second pressure relief valve is not provided on the cylindrical fitting, during the process of the pressure in the battery cell installation cavity rising continuously, the gas and liquid in the battery cell installation cavity can only slowly penetrate and flow into the spare cavity through the gap generated between the cylindrical fitting and the battery housing when forced by the internal pressure. This pressure relief method is relatively fluctuating and uncontrollable. However, in the present invention, by providing the second pressure relief valve on the cylindrical fitting and setting the pressure relief threshold of the second pressure relief valve < the pressure relief threshold of the first pressure relief valve, the second pressure relief valve is actively opened for pressure relief once before the pressure in the battery cell installation cavity reaches the pressure relief threshold of the first pressure relief valve, and then the first pressure relief valve is used for secondary pressure relief, so that the internal pressure of the battery can be released in two stages, and the pressure relief is more controllable, thereby avoiding liquid leakage caused by internal gas expansion when the battery is abnormal.

[0012] Preferably, the cylindrical fitting is a plastic part, which has low cost, is easy to manufacture, and is not likely to scratch the battery housing during installation.

[0013] Preferably, the outer peripheral wall of the cylindrical fitting is adapted to the inner wall of the battery housing, so that the degree of reduction of the accommodation space for the battery cell is determined by the height of the cylindrical fitting, making it easy to adjust and control the accommodation space for the battery cell and the amount of positive and negative electrode materials used. Further, one end of the cylindrical fitting facing away from the battery cell is open, and the mouth edge portion of the cylindrical fitting is sealingly fitted to the inner wall of the battery housing. The inner wall of the cylindrical fitting and the inner wall of the battery housing together enclose the spare cavity. The cylindrical fitting has a simple structure and is easy to manufacture.

[0014] The battery housing is composed of a positive electrode steel shell in a cylindrical shape with only the top end open and a negative electrode current collector installed at the open end of the positive electrode steel shell to seal the open end of the positive electrode steel shell; the negative electrode current collector includes a sealing ring, a negative electrode cover, and a copper needle, and the first pressure relief valve is provided on the sealing ring; the cylindrical fitting is located at the bottom end of the battery cell, and the bottom end of the cylindrical fitting is fitted to the inner wall of the closed end of the positive electrode steel shell. Compared with the top end of the battery cell where the cylindrical fitting is located, the internal structure of the closed end of the positive electrode steel shell is much simpler, and the assembly of the cylindrical fitting is easier. The assembly of the cylindrical fitting will not affect the explosion-proof and air-release effect of the first pressure relief valve of the negative electrode current collector, nor will it affect the connection structure between the negative electrode current collector and the battery cell. Further, a positive electrode terminal is formed by the inner wall center position of the closed end of the positive electrode steel shell being recessed outward, and the spare cavity is connected to the internal space of the positive electrode terminal. At this time, the spare cavity and the internal space of the positive electrode terminal are connected to form a larger gas storage space. The battery cell is composed of a separator tube coaxially sleeved inside the positive electrode steel shell, negative electrode zinc paste (i.e., the negative electrode material) filled in the inner cavity of the separator tube, and a positive electrode ring (i.e., the positive electrode material) embedded in the annular cavity between the separator tube and the positive electrode steel shell. The copper needle of the negative electrode current collector is inserted into the negative electrode zinc paste. Further, the bottom end of the separator tube is closed to form a separator tube bottom surface, and the separator tube bottom surface is fitted to the top surface of the cylindrical fitting. By supporting the separator tube bottom surface with the cylindrical fitting, the bottom of the separator tube is generally closed by heat shrinkage. When the heat shrinkage is poor, zinc powder particles in the negative electrode zinc paste inside the separator tube are likely to leak out from the bottom of the separator tube. In the present invention, the separator tube bottom surface is fitted to the top surface of the cylindrical fitting, which can prevent zinc powder particles from leaking out from the bottom of the separator tube and causing a short circuit. Furthermore, an embedding groove for the bottom of the separator tube is provided on the top surface of the cylindrical fitting, and the outer surface of the bottom of the separator tube and the inner surface of the embedding groove for the separator tube are in contact with each other, providing the best short-circuit prevention effect for protecting the bottom of the separator tube. In the specific implementation process, the second pressure relief valve is the weak part of the cylindrical fitting, and the weak part is in a cross shape, a dot shape, a fan shape, or a circular ring shape. Description of the Drawings

[0015] Figure 1 is a schematic cross-sectional structure view of the anti-seepage liquid cylindrical battery of the present invention;

[0016] Figure 2 is a bottom view of the cylindrical fitting when the second pressure relief valve of the present invention is in a cross shape;

[0017] Figure 3 is a bottom view of the cylindrical fitting when the second pressure relief valve of the present invention is in a fan shape. Embodiment

[0018] The specific embodiments of the anti-seepage liquid cylindrical battery of the present invention will be specifically described below in conjunction with the accompanying drawings:

[0019] Taking an alkaline zinc-manganese dry battery as an example.

[0020] As Figure 1 shown, an anti-seepage liquid cylindrical battery includes a cylindrical battery housing 10, the battery housing 10 has an inner cavity, a cylindrical fitting 30 is provided at the bottom of the inner cavity, the cylindrical fitting 30 divides the inner cavity into two mutually independent and sealed sub-cavities, one of the sub-cavities is filled with a battery core 20 as a battery core installation cavity 11, and the other sub-cavity is used as a spare cavity 31. A first pressure relief valve 40 is provided at the top of the battery housing 10, and when the first pressure relief valve 40 is opened, it communicates the battery core installation cavity 11 with the outside; a second pressure relief valve 50 is provided on the cylindrical fitting 30, and when the second pressure relief valve 50 is opened, it communicates the battery core installation cavity 11 with the spare cavity 31; the pressure relief threshold of the second pressure relief valve 50 < the pressure relief threshold of the first pressure relief valve 40;

[0021] The battery housing 10 is composed of a positive electrode steel shell 101 in a cylindrical shape with only the top open and a negative electrode current collector 102 installed at the open end of the positive electrode steel shell 101 to seal the open end of the positive electrode steel shell 101; the negative electrode current collector 102 includes a sealing ring 1021, a negative electrode cover 1022 and a copper needle 1023, and the first pressure relief valve 40 is provided on the sealing ring 1021;

[0022] The battery core 20 is composed of an isolation tube 21 coaxially sleeved inside the positive electrode steel shell 101, a negative electrode zinc paste 22 (i.e., the negative electrode material) filled in the inner cavity of the isolation tube 21, and a positive electrode ring 23 (i.e., the positive electrode material) embedded in the annular cavity between the isolation tube 21 and the positive electrode steel shell 101. The copper needle of the negative electrode current collector 102 is inserted into the negative electrode zinc paste 22.

[0023] When the first pressure relief valve 40 of the anti-leakage cylindrical battery of the present invention is opened to release pressure, the liquid flowing out of the battery will be greatly reduced, which can effectively improve the leakage phenomenon and the pollution caused by the leakage; and improve the battery's ability to resist leakage. The present invention also sets the pressure relief threshold of the second pressure relief valve 50 to be less than the pressure relief threshold of the first pressure relief valve 40, so that the internal pressure of the battery can be released twice, and the pressure relief is more controllable, thereby avoiding leakage caused by internal gas expansion when the battery is abnormal. At the same time, under the conditions of the same positive electrode material and negative electrode material content, adding a columnar accessory can make the interior of the battery more compact and effectively reduce the internal resistance of the battery. At the same time, the purpose of battery capacity differentiation can be achieved by controlling the volume of the columnar accessory 30, with a simple process, a short battery verification cycle, low cost, and high efficiency, which is conducive to quickly meeting customers' customized needs.

[0024] Preferably, the columnar accessory 30 is a hard part, which is not easy to deform and has a good space-occupying effect. Further preferably, the columnar accessory 30 is a plastic part, which is low in cost, easy to manufacture, and not easy to scratch the battery shell during installation.

[0025] Preferably, Figure 1 As shown, the outer wall of the cylindrical accessory 30 is adapted to the inner wall of the battery housing 10, so that the reduction degree of the accommodation space of the battery cell 20 is determined by the height of the cylindrical accessory 30, and it is easy to adjust and control the amount of battery cells and positive and negative electrode materials. Figure 1 As shown, the end of the cylindrical accessory 30 away from the battery cell 20 is open, the edge 32 of the cylindrical accessory 30 is sealed and fitted with the inner wall of the battery housing 10, and the inner wall of the cylindrical accessory 30 and the inner wall of the battery housing 10 together enclose the spare cavity 31. The cylindrical accessory 30 has a simple structure and is easy to manufacture. Of course, the shape of the cylindrical accessory 30 is not limited to the cylindrical shape shown in the drawings, and it can also be other common shapes, such as square, polygonal and other common shapes.

[0026] Preferably, Figure 1 As shown, the cylindrical fitting 30 is located at the bottom end of the battery cell 20, and the bottom end of the cylindrical fitting 30 fits with the inner wall of the closed end of the positive electrode steel shell 101. Compared with the cylindrical fitting 30 located at the top end of the battery cell 20, the internal structure of the closed end of the positive electrode steel shell 101 is much simpler, and the assembly of the cylindrical fitting 30 is easier. The assembly of the cylindrical fitting 30 will not affect the explosion-proof and air-release effect of the first pressure relief valve 40 of the negative electrode collector 102, nor will it affect the connection structure between the negative electrode collector 102 and the battery cell 20. In the specific implementation process, as Figure 1As shown, the first pressure relief valve 40 is the weak part of the sealing ring 1021, and the strength of the weak part is lower than that of other parts of the main plane of the sealing ring 1021 (for example: realized by the wall thickness of the weak part being thinner than that of other parts of the main plane of the sealing ring 1021). Further, as Figure 1 shown, a positive terminal 110 is formed by inward depression at the center position of the inner wall at one end of the closed positive steel shell 101. The spare cavity 31 is communicated with the internal space 1101 of the positive terminal 110. At this time, the spare cavity 31 and the internal space 1101 of the positive terminal 110 are communicated to form a larger gas storage space. The bottom end of the isolation tube 21 is closed to form the bottom surface of the isolation tube. The bottom surface of the isolation tube is attached to the top surface of the cylindrical fitting 30. The bottom of the isolation tube is supported by the cylindrical fitting 30. Generally, the bottom of the isolation tube is closed by heat shrinkage. When the heat shrinkage is not good, the zinc powder particles in the negative zinc paste 22 inside the isolation tube 21 are likely to leak out from the bottom of the isolation tube 21. In the present invention, the bottom surface of the isolation tube is attached to the top surface of the cylindrical fitting 30, which can avoid the leakage of zinc powder particles from the bottom of the isolation tube 21 and cause a short circuit. Further, as Figure 1 shown, an isolation tube embedding groove 33 for embedding the bottom of the isolation tube 21 is provided on the top surface of the cylindrical fitting 30, and the outer surface of the bottom of the isolation tube 21 and the inner surface of the isolation tube embedding groove 33 are attached to each other, and the effect of protecting the bottom of the isolation tube 21 from short circuit is the best. The second pressure relief valve 50 can be, but is not limited to, provided at the center position on the inner side of the top wall of the cylindrical fitting 30. In the specific implementation process, the second pressure relief valve 50 is the weak part of the cylindrical fitting 30, and the strength of the weak part is lower than that of other parts of the main plane of the cylindrical fitting 30 (for example: realized by the wall thickness of the weak part being thinner than that of other parts of the main plane of the cylindrical fitting 30), and the weak part is in common shapes such as a cross shape, a dot shape, a fan shape, a circular ring shape, etc. (in combination with Figures 1 to 3 ).

[0027] The pressure relief threshold of the first pressure relief valve 40 of the present invention refers to: when the pressure in the battery cell installation cavity exceeds a certain predetermined value, the first pressure relief valve 40 can crack, and this predetermined value is the pressure relief threshold of the first pressure relief valve 40.

[0028] The pressure relief threshold of the second pressure relief valve 50 of the present invention refers to: when the pressure in the battery cell installation cavity exceeds a certain predetermined value, the second pressure relief valve 50 can crack, and this predetermined value is the pressure relief threshold of the second pressure relief valve 50.

[0029] When the first pressure relief valve 40 is a weak part of the sealing ring 1021 and the second pressure relief valve 50 is a weak part of the cylindrical fitting 30, under the condition that the inventors have determined the materials of the sealing ring 1021 and the cylindrical fitting 30, and the structural conditions such as the shapes and sizes of the first pressure relief valve 40 and the second pressure relief valve 50, by adjusting the wall thickness of the sealing ring 1021 at the first pressure relief valve 40 and the wall thickness of the cylindrical fitting 30 at the second pressure relief valve 50, the pressure relief threshold of the second pressure relief valve 50 < the pressure relief threshold of the first pressure relief valve 40 is achieved, so that the battery ruptures first at the second pressure relief valve 50 before the first pressure relief valve during use. For example: when the materials of the sealing ring 1021 and the cylindrical fitting 30 are the same, and the structural conditions such as the shapes and sizes of the first pressure relief valve 40 and the second pressure relief valve 50 are the same, since the external pressure of the first pressure relief valve 40 comes from the atmospheric pressure, if the internal vacuum is not pumped during battery assembly, the internal pressure of the second pressure relief valve 50 is also basically equal to the atmospheric pressure. As long as the wall thickness of the sealing ring 1021 at the first pressure relief valve 40 is adjusted to be less than the wall thickness of the cylindrical fitting 30 at the second pressure relief valve 50, it can be achieved that: the pressure relief threshold of the second pressure relief valve 50 < the pressure relief threshold of the first pressure relief valve 40, and the second pressure relief valve 50 ruptures before the first pressure relief valve during battery use.

[0030] Of course, the technical solution of the present invention is not only applicable to alkaline zinc-manganese dry batteries, but also applicable to other various types of cylindrical batteries.

[0031] The specific structures of the battery case 10, the battery core 20 and the negative current collector 102 of the present invention are all conventional structures of existing alkaline zinc-manganese dry batteries.

[0032] For those of ordinary skill in the art to which the present invention pertains, without departing from the concept of the present invention, several simple deductions or substitutions can still be made, and all should be regarded as belonging to the protection scope of the present invention.

Claims

1. An anti-seepage liquid columnar battery, comprising a columnar battery housing having an inner cavity, characterized in that: A columnar fitting is provided at the bottom of the inner cavity, and the columnar fitting divides the inner cavity into two mutually independent and sealed sub-cavities. One of the sub-cavities is filled with a battery cell as a battery cell installation cavity, and the other sub-cavity is used as a spare cavity. A first pressure relief valve is provided at the top end of the battery housing, and when the first pressure relief valve is opened, it communicates the battery cell installation cavity with the outside; a second pressure relief valve is provided on the columnar fitting, and when the second pressure relief valve is opened, it communicates the spare cavity with the battery cell installation cavity; the pressure relief threshold of the second pressure relief valve < the pressure relief threshold of the first pressure relief valve; the outer peripheral wall of the columnar fitting is adapted to the inner wall of the battery housing; the end of the columnar fitting facing away from the battery cell is open, and the mouth edge portion of the columnar fitting is in sealing fit with the inner wall of the battery housing, and the inner wall of the columnar fitting and the inner wall of the battery housing together enclose the spare cavity.

2. The anti-seepage liquid columnar battery according to claim 1, characterized in that: The columnar fitting is a plastic part.

3. The anti-seepage liquid columnar battery according to claim 1, characterized in that: The battery housing is composed of a positive electrode steel shell in a cylindrical shape with only the top end open and a negative electrode current collector installed at the open end of the positive electrode steel shell to seal the open end of the positive electrode steel shell; the negative electrode current collector includes a sealing ring, a negative electrode cover and a copper needle, and the first pressure relief valve is provided on the sealing ring; the columnar fitting is located at the bottom end of the battery cell, and the bottom end of the columnar fitting is in contact with the inner wall of the closed end of the positive electrode steel shell.

4. The anti-seepage liquid columnar battery according to claim 3, characterized in that: A positive electrode terminal is formed by the inner wall center position of the closed end of the positive electrode steel shell being recessed outward, and the spare cavity is communicated with the internal space of the positive electrode terminal.

5. The anti-seepage liquid columnar battery according to claim 3, characterized in that: The battery cell is composed of an isolation tube coaxially sleeved in the positive electrode steel shell, a negative electrode zinc paste filled in the inner cavity of the isolation tube, and a positive electrode ring embedded in an annular cavity between the isolation tube and the positive electrode steel shell. The copper needle of the negative electrode current collector is inserted into the negative electrode zinc paste; the bottom end of the isolation tube is closed to form an isolation tube bottom surface, and the isolation tube bottom surface is in contact with the top surface of the columnar fitting.

6. The anti-seepage liquid columnar battery according to claim 5, wherein: An isolation tube embedding groove for embedding the bottom of the isolation tube is provided on the top surface of the columnar fitting, and the outer surface of the bottom of the isolation tube is in contact with the inner surface of the isolation tube embedding groove.

7. The anti-seepage liquid columnar battery according to claim 1, wherein: The second pressure relief valve is a weak part of the columnar fitting, and the weak part is in a cross shape or a dot shape or a fan shape or a circular ring shape.

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