A button-type lithium manganese battery

Abstract

The application discloses a button type lithium-manganese battery, which comprises a positive electrode, a negative electrode, a diaphragm and a sealing ring; the positive electrode comprises a positive electrode cup shell, a positive electrode active cake arranged in the positive electrode cup shell and a current collecting grid; the negative electrode comprises a negative electrode cup cover and a negative electrode active cake arranged in the negative electrode cup cover; the sealing ring is arranged between the negative electrode cup cover and the positive electrode cup shell to connect the two; the diaphragm is arranged between the negative electrode active cake and the positive electrode active cake; wherein the positive electrode active cake comprises a sleeve cup and a positive electrode active substance which is press-formed in the sleeve cup; the sleeve cup is provided with a bottom wall and a protruding part arranged on the bottom wall and facing the positive electrode active substance, and the protruding part is inserted into the positive electrode active substance when the positive electrode active substance is press-formed in the sleeve cup. The application can realize uniform pressure relief when the positive electrode active substance is press-formed in the sleeve cup, so that the positive electrode active substance remains flat after absorbing electrolyte to realize plane close contact, thereby increasing the current density, realizing the stability of the voltage power supply and increasing the output power.

Description

Technical Field

[0001] This invention relates to the field of batteries, and more specifically to a button-type lithium manganese battery. Background Technology

[0002] In today's rapidly evolving world of science and technology, electronic products are developing at a breakneck pace. The operation and use of these electronic products must be driven by electrical energy conversion. Typically, lithium manganese batteries are used as the power source in electronic products. Lithium manganese batteries have the advantages of relatively stable voltage output, no charge-discharge effect, and protection against radio wave interference, making them a promising choice for applications.

[0003] With the advancement of modernization, battery products also need to adapt to the development of current electronic products. They not only need to be lightweight, portable, and easy to replace, but also need to meet the requirements of high power output without radio interference. In addition, some electronic products require a stable voltage power supply, especially the driving power supply for collecting databases at the back end of high-end medical instruments, where the requirements for voltage stability and high power output are particularly stringent.

[0004] However, in existing lithium-manganese batteries, the positive electrode active cake is prone to bending after absorbing electrolyte, resulting in reduced current density, lower output power, and fluctuations. Therefore, it is desirable to improve existing lithium-manganese batteries to achieve stable voltage supply and increased output power to meet the needs of modern electronic applications. Summary of the Invention

[0005] The main objective of this invention is to provide a coin cell lithium manganese battery with a stable voltage power supply and high output power.

[0006] To achieve the above-mentioned main objectives, the present invention provides a button-type lithium manganese battery, comprising a positive electrode, a negative electrode, a separator, and a sealing ring;

[0007] The positive electrode includes a positive electrode cup shell, a positive electrode active cake disposed inside the positive electrode cup shell, and a current collector located between the positive electrode cup shell and the positive electrode active cake;

[0008] The negative electrode includes a negative electrode cup cap and a negative electrode active cake disposed in the negative electrode cup cap;

[0009] The sealing ring is located between the negative electrode cup cap and the positive electrode cup shell to make a circumferential connection between the two; the diaphragm is located between the negative electrode active cake and the positive electrode active cake;

[0010] The positive electrode active cake includes a sleeve cup and a positive electrode active material compressed and formed in the sleeve cup; the sleeve cup has a bottom wall and protrusions disposed on the bottom wall facing the positive electrode active material, and the protrusions are inserted into the positive electrode active material when the positive electrode active material is compressed and formed into the sleeve cup.

[0011] According to one specific embodiment of the present invention, the protruding part has a conical structure with a smaller upper end and a larger lower end.

[0012] According to a specific embodiment of the present invention, the height of the protrusion is set to 1 / 5 to 1 / 2 of the total height of the positive electrode active cake.

[0013] According to one specific embodiment of the present invention, the bottom wall also has a through hole, into which the positive electrode active material is filled when it is pressed into the sleeve cup.

[0014] Furthermore, the hole includes a central hole and edge holes, with multiple edge holes distributed or arranged in pairs relative to the central hole array.

[0015] Furthermore, the flow collection network completely covers the central aperture.

[0016] According to a specific embodiment of the present invention, the upper surface of the bottom wall facing the positive electrode active material is provided with a recessed pattern area, and the positive electrode active material fills the recessed pattern area when the positive electrode active material is pressed into the sleeve cup.

[0017] Furthermore, the pattern shape of the recessed pattern area includes one or more of the following: square, rectangle, triangle, or circle.

[0018] According to a specific embodiment of the present invention, the diaphragm is a bowl-shaped diaphragm with an opening at the bottom; wherein, the lower edge of the diaphragm intersects with the sealing ring, and the intersection length between the lower edge of the diaphragm and the sealing ring is set to be not less than 0.5 mm.

[0019] According to a specific embodiment of the present invention, the positive electrode active cake is prepared by the following method: the positive electrode active material is pressed and shaped in a sleeve cup using a top pressing mold and a bottom pressing mold; wherein, the bottom pressing mold is provided with a protruding pin portion on the bottom wall facing the sleeve cup, and when the positive electrode active material is pressed and shaped into the sleeve cup, the protruding pin portion acts on the bottom wall of the sleeve cup to deform the bottom wall of the sleeve cup to form a protruding burr portion facing the positive electrode active material, and at the same time, the protruding burr portion is inserted into the positive electrode active material.

[0020] The present invention has the following beneficial effects:

[0021] The positive electrode active cake of this invention includes a sleeve cup and a positive electrode active material pressed and formed in the sleeve cup. The bottom wall of the sleeve cup is provided with protrusions. When the positive electrode active material is pressed and formed into the sleeve cup, the protrusions are inserted into the positive electrode active material. This not only better fixes the positive electrode active material, but also increases the current collection and energy enrichment effect when the chemical energy of the positive electrode active material is converted into electrical energy. At the same time, the presence of the protrusions can also achieve uniform force dissipation during the pressing and forming of the positive electrode active material into the sleeve cup, so that the positive electrode active material can remain flat after absorbing the electrolyte and achieve a tight plane, thereby increasing the current density while stabilizing the voltage power supply and increasing the output power.

[0022] To more clearly illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0023] Figure 1 This is a structural diagram of an embodiment of the button-type lithium manganese battery of the present invention;

[0024] Figure 2 This is a structural diagram of the negative electrode cup cover in an embodiment of the button-type lithium manganese battery of the present invention;

[0025] Figure 3 This is a structural diagram of the sealing ring in an embodiment of the button-type lithium manganese battery of the present invention;

[0026] Figure 4 This is a structural diagram of the positive electrode cup shell in an embodiment of the button-type lithium manganese battery of the present invention;

[0027] Figure 5 This is a structural diagram of the current collector network in an embodiment of the button lithium manganese battery of the present invention;

[0028] Figure 6 This is a structural diagram of the positive electrode active cake in an embodiment of the button lithium manganese battery of the present invention;

[0029] Figure 7 This is a top view of the sleeve cup in an embodiment of the button lithium manganese battery of the present invention;

[0030] Figure 8 This is a vertical sectional view of the sleeve cup in an embodiment of the button-type lithium manganese battery of the present invention. Detailed Implementation

[0031] Many specific details are set forth in the following description to provide a thorough understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below. The following embodiments are described with the negative electrode side above and the positive electrode side below.

[0032] The coin cell lithium manganese battery of the embodiment, such as Figure 1 As shown, the electrode includes a positive electrode 10, a negative electrode 20, a separator 30, and a sealing ring 40. The positive electrode 10 includes a positive electrode cup shell 11, a positive electrode active cake 12, and a current collector 13. The positive electrode active cake 12 is disposed inside the positive electrode cup shell 11, and the current collector 13 is located between the positive electrode cup shell 11 and the positive electrode active cake 12. The negative electrode 20 includes a negative electrode cup cover 21 and a negative electrode active cake 22 disposed in the negative electrode cup cover 21. The sealing ring 40 is located between the negative electrode cup cover 21 and the positive electrode cup shell 11 to form a circumferential connection between the two. The separator 30 is located between the negative electrode active cake 22 and the positive electrode active cake 12.

[0033] The negative electrode cup cap 21 is preferably made of 304 stainless steel sheet, 316 stainless steel sheet, 430 stainless steel sheet, or a new type of gradient annealed rust-proof iron sheet. Preferably, the sheet thickness of the negative electrode 20 cup cap is generally between 0.10 and 0.50 mm, preferably between 0.25 and 0.30 mm. The outer diameter and height of the negative electrode 20 cup cap are determined according to the designed outer diameter of the battery. To increase hardness and rust prevention, the surface of the sheet material used to manufacture the negative electrode 20 cup cap is preferably treated with surface treatment, such as chemical electroplating and physical vapor deposition. The anti-corrosion layer on the surface of the negative electrode cup cap 21 can be a nickel layer, titanium layer, silver layer, or gold layer. Alternatively, a thin anti-corrosion layer can be composite-rolled into a clip. The composite rolling can be done by heating the sheet material and rolling it together with a rolling machine, or by directly rolling and forming the composite without heating. Then, the sheet material is punched and cut into round pieces by forming hardware molds, then pushed into the forming molds, and the upper and lower molds fit together to form the final product. Figure 2 The negative electrode cup lid 21 is shown.

[0034] Specifically, the negative electrode cup cover 21 has a top wall 211, a folded outer peripheral wall 212, and a transition connecting wall 213, which connects the top wall 211 and the folded outer peripheral wall 212. The top wall 211 is planar, and the folded outer peripheral wall 212 has a U-shaped fold, including an outer folded outer wall 2121 and an inner folded inner wall 2122, which overlap. Preferably, the transition connecting wall 213 is an arc-shaped wall with two continuous transition R-angle connection positions 214, which connect to the top wall 211 and the folded outer peripheral wall 212, respectively.

[0035] Furthermore, the top wall 211 of the negative electrode cup cover 21 is constricted; wherein, the outer edge diameter of the top wall 211 is generally recessed by less than 1.0 mm compared to the diameter of the outer peripheral wall 212 of the folded edge. Preferably, the recessed distance of the outer edge diameter of the top wall 211 compared to the outer peripheral wall 212 of the folded edge is 1.5-3 times the thickness of the negative electrode cup cover 21, specifically, for example, 2 times. That is, when the thickness of the negative electrode cup cover 21 (specifically, the thickness of the sheet material used to make the negative electrode cup cover 21) is 0.3 mm, the recessed distance of the outer edge diameter of the top wall 211 is 0.6 mm.

[0036] The sealing ring 40 is preferably made of a corrosion-resistant material resistant to acids, alkalis, and organic solvents, such as modified polypropylene, polyphenylene sulfide, polyetheretherketone, etc., into a strong corrosion-resistant plastic; specifically, the sealing ring 40 is formed by hot injection molding; such as Figure 3 As shown, the longitudinal section of the sealing ring 40 is U-shaped, having a bottom 41 and sealing inner wall 42 and sealing outer wall 43 located on opposite sides of the bottom 41. A groove 44 is formed between the sealing inner wall 42 and the sealing outer wall 43, which is used to accommodate the folded outer peripheral wall 212. The inner surface of the sealing outer wall 43 is in contact with the folded outer outer wall 2121 of the folded outer peripheral wall 212. Furthermore, the bottom of the groove 44 has a recess 45 adjacent to the sealing outer wall 43. The width of the recess 45 is the same as the width of the folded outer peripheral wall 212 to cooperate with the folded outer peripheral wall 212 and provide guidance for the installation of the sealing ring 40.

[0037] The positive electrode cup shell 11 is preferably made of 304 stainless steel sheet, 316 stainless steel sheet, 430 stainless steel sheet, or a new type of gradient annealed rust-proof iron sheet. Preferably, the sheet thickness of the positive electrode cup shell 11 is generally between 0.10 and 0.50 mm, and more preferably between 0.25 and 0.30 mm. The outer diameter and height of the positive electrode cup shell 11 are determined according to the designed outer diameter of the battery. To increase hardness and rust prevention, the surface of the sheet material used to prepare the positive electrode cup shell 11 can preferably be surface treated, such as chemical electroplating and physical vapor deposition. The anti-corrosion layer on the surface of the positive electrode cup shell 11 can be a nickel layer, titanium layer, silver layer, or gold layer. Alternatively, a thin anti-corrosion layer can be composite-rolled into a clip. The composite rolling can be done by heating the sheet and rolling it together with a rolling machine, or by directly rolling and forming the composite without heating. Then, the sheet is punched and cut into a round piece by a forming hardware mold, then pushed into the forming mold, and the upper and lower molds fit together to form and remove the piece, thus obtaining the desired shape. Figure 4 The positive electrode cup shell 11 is shown.

[0038] Specifically, the positive electrode cup shell 11 has a cup bottom 111 and a cup outer wall 112; the cup bottom 111 is flat, and the cup outer wall 112 is slightly flared before sealing; wherein, when the sealing ring 40 is installed in the positive electrode cup shell 11, the top of the cup outer wall 112 is preferably flush with the top of the sealing outer wall 43.

[0039] The current collector mesh 13 is preferably made of 304 stainless steel sheet, 316 stainless steel sheet, 430 stainless steel sheet, or a new type of graded annealed rust-proof iron sheet; to increase hardness and rust prevention, the surface of the sheet material used to prepare the current collector mesh 13 is preferably treated with surface treatment, such as chemical electroplating and physical vapor deposition; the anti-corrosion layer on the surface of the current collector mesh 13 can be a nickel layer, titanium layer, silver layer, or gold layer, or it can be made by bonding and rolling thin anti-corrosion layers together. The bonding and rolling can be done by heating the sheet material and bonding it together with a rolling machine, or by directly bonding and rolling it together without heating; then, it can be cut to obtain the desired shape. Figure 5 The shown is a current-collecting mesh 13 with a plurality of current-collecting mesh openings 131, wherein the shape of the current-collecting mesh openings 131 can be rhomboid, square, or triangular, etc. In an optional embodiment, the current-collecting mesh 13 can also be obtained by weaving, which will not be elaborated here.

[0040] The exemplary preparation process of the button lithium manganese battery in the embodiment is as follows: First, a circular and flat negative electrode active cake 22 is placed in the negative electrode cup cover 21 and attached to the inner surface of the top wall 211 of the negative electrode cup cover 21; then, a separator 30 is placed in the negative electrode cup cover 21 and attached to the negative electrode active cake 22; wherein, the separator 30 is preferably a bowl-shaped separator 30 with an opening at the bottom.

[0041] Next, electrolyte is added to the diaphragm 30; after the addition is completed, the positive electrode active cake 12 is placed on the diaphragm 30 and adhered to the diaphragm 30; wherein, the positive electrode active cake 12 can be pre-soaked in saturated electrolyte or electrolyte can be added directly to the positive electrode active cake 12.

[0042] Then, place the current collector 13 on the center of the surface of the positive electrode active cake 12 away from the diaphragm 30; at the same time, place the sealing ring 40 on the outer peripheral wall 212 of the folded edge of the negative electrode cup cover 21 and keep the lower edge of the diaphragm 30 in contact with the sealing ring 40 to prevent the positive electrode active cake 10 from contacting the inner surface of the negative electrode cup cover 21 and causing an internal short circuit; wherein, the intersection length between the lower edge of the diaphragm 30 and the sealing ring 40 is preferably set to not less than 0.5 mm, for example, the intersection length is 1 mm to 3 mm, specifically, for example, 1.5 mm.

[0043] Finally, the above-mentioned assembly is fitted into the positive electrode cup shell 11 and tightly assembled. In a dry environment with a low dew point below -45°C, the opening of the positive electrode cup shell 11 is radially recessed and molded using a molding die to fix the parts and achieve a tight seal (during this process, the outer wall 112 of the positive electrode cup shell 11 and the sealing outer wall 43 of the sealing ring 40 deform and press against the transition connecting wall 213 of the negative electrode cup cover 21), thus obtaining the button lithium manganese battery of the embodiment.

[0044] In this embodiment, the negative electrode active cake 22 is an effective active material for negative electrode energy, such as battery-grade high-purity lithium, or lithium-aluminum alloy or lithium-magnesium alloy that improves lithium forming. The separator 30 is a thin sheet that separates the positive and negative electrode active materials, and is made of a material that can withstand the corrosion of organic solvents, such as polypropylene, polyphenylene sulfide, polyetheretherketone, polytetrafluoroethylene, glass fiber, etc. The positive electrode active cake 12 is an effective active material for positive electrode energy, and its main components are, for example, a mixture of manganese dioxide, conductive agent and binder. The manganese dioxide can be modified phase change β-electrolytic manganese dioxide or direct phase change chemical β-manganese dioxide.

[0045] Furthermore, the negative electrode active cake 22 is in close contact with the negative electrode cup cover 21, and the positive electrode active cake 12 is in close contact with the positive electrode cup shell 11 through the current collector 13. The other internal components are in close contact with each other, and the electrolyte wets each positive and negative electrode and the diaphragm 30, so that an electrochemical electrolytic cell is formed inside. When the external positive and negative electrodes are turned on, the internal ions are converted to output high power energy through the ion movement of electromotive force.

[0046] The positive electrode active cake 12 in the embodiment is an assembly, which includes a sleeve cup 121 and a positive electrode active material 122 compressed and formed in the sleeve cup 121. The sleeve cup 121 has good conductivity and structural stability, which can protect the positive electrode active material 122 from bursting during the discharge process.

[0047] The sleeve cup 121 is preferably made of 304 stainless steel sheet, 316 stainless steel sheet, 430 stainless steel sheet or new type of gradient annealed rust-proof iron sheet; to increase hardness and rust prevention, the surface of the sheet material used to prepare the sleeve cup 121 can preferably be surface treated, such as chemical electroplating and physical vapor phase sputtering treatment; the anti-corrosion layer set on the surface of the sleeve cup 121 can be a nickel layer, titanium layer, silver layer, gold layer, or a thin anti-corrosion layer can be composite rolled into a clip. The composite rolling can be done by heating the sheet material and forming it through a rolling machine, or it can be directly rolled and formed without heating; then, the sheet material is punched and cut into a round piece by forming hardware mold, then pushed into the forming mold, and the upper and lower molds fit together to form and remove the piece.

[0048] The existing technology for pressing the positive electrode active material 122 and the sleeve cup 121 typically involves placing the disc-shaped positive electrode active material 122 directly into the sleeve cup 121 and pressing them together tightly using a mold and a punch. However, the sleeve cup 121 has a large internal space, and during the pressing process, the positive electrode active material 122 is prone to uneven stress distribution, resulting in uneven stress release. This leads to uneven density at different locations of the positive electrode active material 122, especially at the edges adjacent to the bottom wall 111 of the sleeve cup 121, where the phenomenon is more pronounced. After the positive electrode active material 122 absorbs the electrolyte, the resulting positive electrode active cake 12 is prone to poor flatness or even slight bending, which reduces the tightness of the fit between the positive electrode active material 122 and the sleeve cup 121, resulting in a decrease in current density and ultimately affecting the output voltage and power.

[0049] To address the aforementioned problems, the sleeve cup 121 of the embodiment has a bottom wall 1211 and a protrusion 1212 disposed on the bottom wall 1211 and facing the positive electrode active material 122, such as... Figure 6 As shown, when the positive electrode active material 122 is pressed into the sleeve cup 121, the protrusion 1212 is inserted into the positive electrode active material 122. In this embodiment, a top pressing mold and a bottom pressing mold are used to press the positive electrode active material 122 into the sleeve cup 121. For example, the bottom pressing mold has a protruding pin on the bottom wall 1211 facing the sleeve cup 121. When the positive electrode active material 122 is pressed into the sleeve cup 121, the protruding pin acts on the bottom wall 1211 of the sleeve cup 121, causing the bottom wall 1211 of the sleeve cup 121 to deform and form the protrusion 1212 facing the positive electrode active material 122, thereby inserting the protrusion 1212 into the positive electrode active material 122. Specifically, the protrusion 1212 can be through-hole or closed. In an alternative embodiment, the protrusion 1212 may also be prefabricated directly on the bottom wall 1211, for example, by welding on the upper surface of the bottom wall 1211 facing the positive electrode active material 122.

[0050] The protruding portion 1212 is preferably a conical structure with a smaller upper end and a larger lower end, such as a frustum of a cone, a frustum of a triangular pyramid, or a frustum of a square pyramid. Further, the height of the protruding portion 1212 is set to 1 / 5 to 1 / 2 of the total height of the positive electrode active cake 12, and specifically, for example, 1 / 3 of the total height of the positive electrode active cake 12. The protruding portion 1212 can not only better fix the positive electrode active material 122, but also increase the current collection and energy enrichment effect when the chemical energy of the positive electrode active material 122 is converted into electrical energy. At the same time, the presence of the protruding portion 1212 can also achieve uniform force release when the positive electrode active material 122 is pressed into the sleeve cup 121, so that the positive electrode active material 122 remains flat after absorbing the electrolyte to achieve a tight plane, thereby increasing the current density while stabilizing the voltage power supply and increasing the output power.

[0051] In addition, the protrusion 1212 is inserted into the positive active material 122 during the forming stage of the positive active cake 12, which can maintain the stability of the positive active cake 12 structure. At the same time, the outer surface of the bottom 111 wall of the sleeve cup 121 in the positive active cake 12 remains flat, which is conducive to its fit with the current collector 13, thereby increasing the current density, so as to achieve the stability of the voltage power supply and the increase of the output power.

[0052] Furthermore, the protruding portion 1212 preferably has multiple edge protrusions, which are preferably distributed in a circumferential array. During the compression molding process, the multiple edge protrusions can directly promote uniform stress relief in the outer edge region of the positive electrode active material 122, which is beneficial to maintaining uniform density of the positive electrode active material 122 at various locations. In an optional embodiment, the protruding portion 1212 also has multiple central protrusions, which are formed as needed in the central region of the bottom wall 1211 to cooperate with the edge protrusions to achieve uniform stress relief of the positive electrode active material 122.

[0053] In this embodiment, the bottom wall 1211 also has a through hole. When the positive electrode active material 122 is pressed into the sleeve cup 121, the positive electrode active material 122 fills the hole to achieve force relief at the corresponding position. Specifically, the hole includes a central hole 1213 and edge holes 1214. There are multiple edge holes 1214, which are arranged in an array or in pairs relative to the central hole 1213. Figure 7 The eight arrays shown are configured with edge holes 1214.

[0054] The central hole 1213 is relatively large, preferably a circular hole, with a diameter preferably 1 / 10 to 2 / 5 of the diameter of the bottom wall 1211. Specifically, the diameter of the central hole 1213 is, for example, 1 / 4 of the diameter of the bottom wall 1211. The edge hole 1214 is relatively small, also preferably a circular hole, with a diameter preferably 2 / 5 to 3 / 5 of the diameter of the central hole 1213. Specifically, the diameter of the edge hole 1214 is, for example, 1 / 2 of the diameter of the central hole 1213. In other embodiments, the shapes of the central hole 1213 and the edge hole 1214 can also be other shapes, such as square, which will not be elaborated here. Preferably, the central hole 1213 is configured not to extend beyond the collecting mesh 13, meaning that the collecting mesh 13 can completely cover the central hole 1213 in the horizontal plane.

[0055] Furthermore, in this embodiment, the bottom wall 1211 has a recessed pattern region 1215 on its upper surface facing the positive electrode active material 122. When the positive electrode active material 122 is pressed into the sleeve cup 121, the positive electrode active material 122 fills the recessed pattern region 1215. The pattern shape of the recessed pattern region 1215 includes one or more of the following: square, rectangle, triangle, or circle. Figure 7 The diagram shows several arrays of square patterns; in other embodiments, other regular or irregular patterns can also be set as needed, which will not be elaborated here.

[0056] Although the present invention has been described above through embodiments, it should be understood that the above embodiments are only used to exemplarily describe possible implementations of the present invention and should not be construed as limiting the scope of protection of the present invention. That is, any substitutions or changes made by those skilled in the art in accordance with the present invention should also be covered by the scope of protection of the claims of the present invention.

Claims

1. A button lithium manganese battery, comprising a positive electrode, a negative electrode, a separator and a sealing ring; the positive electrode comprises a positive electrode cup shell, a positive electrode active cake arranged in the positive electrode cup shell and a current collector grid between the positive electrode cup shell and the positive electrode active cake; the negative electrode comprises a negative electrode cup cover and a negative electrode active cake arranged in the negative electrode cup cover; the sealing ring is located between the negative electrode cup cover and the positive electrode cup shell for the circumferential connection of the two; the separator is located between the negative electrode active cake and the positive electrode active cake; wherein the positive electrode active cake comprises a sleeve cup and a positive electrode active material compression molded in the sleeve cup; the sleeve cup has a bottom wall and a protruding part arranged on the bottom wall and towards the positive electrode active material, which is inserted into the positive electrode active material when the positive electrode active material is compression molded into the sleeve cup; the bottom wall is provided with a recessed pattern area towards the upper surface of the positive electrode active material, which is filled into the recessed pattern area when the positive electrode active material is compression molded into the sleeve cup; the bottom wall also has a through hole, which is filled into the hole when the positive electrode active material is compression molded into the sleeve cup; the hole comprises a center hole and a plurality of edge holes, which are arranged in an array or in pairs relative to the center hole; the current collector grid completely covers the center hole.

2. The button lithium manganese battery of claim 1, wherein: The protruding part has a tapered structure with a small upper end and a large lower end.

3. The button lithium manganese battery of claim 1, wherein: The height of the protruding part is set to 1 / 5-1 / 2 of the total height of the positive electrode active cake.

4. The button lithium manganese battery of claim 1, wherein: The pattern shape of the recessed pattern area comprises one or more of square, rectangle, triangle or circle.

5. The button lithium manganese battery of claim 1, wherein: The separator is a bowl-shaped separator with an open bottom; wherein the lower edge of the separator intersects with the sealing ring, and the intersection length of the lower edge of the separator and the sealing ring is set to not less than 0.5mm.

6. The button lithium manganese battery of claim 1, wherein: The positive electrode active cake is prepared by using a top compression mold and a bottom compression mold to compression mold the positive electrode active material in the sleeve cup; wherein the bottom compression mold is provided with a protruding needle part towards the bottom wall of the sleeve cup, which acts on the bottom wall of the sleeve cup when the positive electrode active material is compression molded into the sleeve cup to deform the bottom wall of the sleeve cup to form the protruding part towards the positive electrode active material, and at the same time, the protruding part is inserted into the positive electrode active material.

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