Wound button cell and electroacoustic device

Abstract

In order to overcome the problem in the prior art that a magnetic field generated by a wound button cell interferes with an electrical appliance such as a portable electroacoustic device, the present invention provides a wound button cell and an electroacoustic device. The button cell consists of a casing, a cover body, and a jelly roll; the casing and the cover body are assembled to form a closed cavity, and the jelly roll is placed in the closed cavity; at least part of the cover body and / or at least part of the casing are / is provided as a corrosion-resistant magnetic shielding portion; and the corrosion-resistant magnetic shielding portion is made of a metal material having relative magnetic permeability greater than or equal to 50 and a chromium element content greater than 10 wt%, and the metal material is provided as a first metal material. The wound button cell provided by the present invention can greatly reduce the impact of a magnetic field generated by the jelly roll on the exterior of the button cell while ensuring that the casing has good corrosion resistance, and cannot cause an increase in the overall dimensions of the button cell or a reduction in the internal space, thereby achieving significant advantages.

Description

A wound button battery and an electroacoustic device

[0001] This application claims priority to Chinese Patent Application No. 202411868800.5, filed on December 18, 2024, entitled “A Winded Button Battery and Electroacoustic Device”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This invention belongs to the field of battery manufacturing technology, specifically relating to a wound button battery and an electroacoustic device using the button battery. Background Technology

[0003] Button batteries are cylindrical batteries whose height is less than their diameter. Jelly rolls are manufactured by winding the core, which allows the electrodes to be made very thin. This enables lithium batteries, which use organic electrolytes with poor ionic conductivity, to have better rate performance, and they are widely used in electronic devices such as Bluetooth headsets.

[0004] Because the winding structure creates a certain inductance, it interferes with the magnetic field of electrical appliances. For example, the current pulse when Bluetooth headphones transmit signals may cause the winding core to generate a strong alternating magnetic field. This magnetic field interacts with the electromagnetic induction sound-generating device of the electroacoustic device, producing so-called background noise, which affects the sound effect of the electroacoustic device.

[0005] An existing button cell battery includes a casing and an electrode assembly. The casing contains a sealed cavity, and the electrode assembly is disposed within this cavity, which is filled with electrolyte. The electrode assembly comprises a separator, a positive electrode, another separator, and a negative electrode, stacked sequentially. A connecting metal plate is fixedly connected to the electrode assembly, with its other end fixedly connected to the casing. This stacked structure eliminates the inductive characteristics of a wound structure and prevents strong alternating magnetic fields generated by current pulses. However, the production efficiency of a stacked structure is very low; moreover, the electrical connection between the positive and negative electrodes requires a significant amount of space, which, for a small-diameter button cell battery, would drastically reduce the battery's design capacity and render it impractical. Summary of the Invention

[0006] To address the problem of magnetic field interference in electrical appliances caused by wound button batteries in existing technologies, a wound button battery and an electroacoustic device are provided. Attached Figure Description

[0007] Figure 1 is a schematic diagram of the first type of wound button battery structure provided by the present invention;

[0008] Figure 2 is a partial structural schematic diagram of the first type of wound button battery structure provided by the present invention;

[0009] Figure 3 is a partial structural schematic diagram of a portable electroacoustic device using the first type of wound button battery structure provided by the present invention.

[0010] Figure 4 is a partial structural schematic diagram of another portable electroacoustic device using the first type of wound button battery structure provided by the present invention.

[0011] Figure 5 is a cross-sectional structural diagram of the second type of wound button battery provided by the present invention;

[0012] Figure 6 is a partial structural schematic diagram of a portable electroacoustic device using the second type of wound button battery structure provided by the present invention.

[0013] Figure 7 is a partial structural schematic diagram of another portable electroacoustic device using the second type of wound button battery structure provided by the present invention. Detailed Implementation

[0014] To make the technical problems solved, the technical solutions, and the beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0015] In the description of this invention, it should be understood that the terms "longitudinal," "radial," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0016] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0017] Referring to Figures 1, 2, and 5, the present invention provides a wound button battery, including a housing 1, a cover 2, and a winding core 3. The housing 1 and the cover 2 are assembled to form a sealed cavity 4, and the winding core 3 is placed in the sealed cavity 4.

[0018] Optionally, the positive electrode of the core 3 is connected to one of the housing 1 and the cover 2, and the negative electrode of the core 3 is connected to the other of the housing 1 and the cover 2;

[0019] At least a portion of the cover 2 and / or at least a portion of the shell 1 are configured as corrosion-resistant magnetic shielding parts 7; the corrosion-resistant magnetic shielding parts 7 are made of a first metal material with a relative magnetic permeability ≥50 and chromium content >10wt%;

[0020] The first metallic material is austenitic and ferritic duplex stainless steel.

[0021] On the one hand, since at least a portion of the cover 2 and / or the shell 1 uses a metal material with a relative magnetic permeability ≥50, this material can shield and consume the magnetic field generated by the current flowing through the core 3, thereby reducing the interference of the magnetic field inside the wound button battery on the portable sound-generating device. Moreover, this method of shielding and consuming the magnetic field does not increase the volume of the battery and has good application value.

[0022] On the other hand, the first metal material of the cover 2 and the shell 1 in this application has a high relative magnetic permeability and good corrosion resistance, thereby avoiding the corrosion problem of the electrolyte in the wound button battery on the magnetic shielding part.

[0023] In summary, this application has significant advantages in reducing the interference of the internal magnetic field of the battery cell to the external environment and improving the corrosion resistance of the magnetic shielding.

[0024] Specifically, the wound button battery of this application is suitable for portable sound-generating devices or other electrical devices that may be affected by the magnetic field of the winding core 3 of the wound button battery.

[0025] Specifically, the core 3 is formed by winding a positive electrode sheet, a negative electrode sheet, and a separator;

[0026] Specifically, the amount of chromium added to the corrosion-resistant magnetic shielding part 7 includes, but is not limited to, 11wt%, 15wt%, 19wt%, 20wt%, 25wt%, or 30wt%. Sufficiently high chromium content helps to generate a good passivation film to prevent corrosion of the metal material.

[0027] Specifically, the relative magnetic permeability of the metal material used to prepare at least a portion of the cover 2 and / or the shell 1 includes, but is not limited to, 60, 100, 150, 200, 300, 350, 400, 450, 500 or 1000; sufficiently high magnetic permeability is beneficial for shielding the magnetic field generated by the core.

[0028] Referring to FIG3, in some embodiments, the cover 2 includes an electrode terminal 22, a metal substrate 21, and a first insulating ring 23 for sealingly connecting the electrode terminal 22 and the metal substrate 21, wherein the metal substrate 21 is welded to the housing 1; the metal substrate 21 and / or the electrode terminal 22 and / or the housing 1 are configured as the corrosion-resistant magnetic shielding part 7.

[0029] Specifically, the metal substrate 21 and / or the electrode terminal 22 and / or the housing 1 are configured as the corrosion-resistant magnetic shielding part 7, which is beneficial to improving the magnetic shielding performance and corrosion resistance of the wound button battery.

[0030] Specifically, the material of the first insulating ring 23 includes, but is not limited to, polymer insulating materials such as PP, PE, PBT, and epoxy resin, or inorganic insulating materials such as ceramics, or mixtures thereof.

[0031] In some embodiments, the electrode terminal 22 is configured as the corrosion-resistant magnetic shielding part 7, and the metal substrate 21 and the housing 1 are made of a second metal material; the projected area of ​​the electrode terminal 22 on the plane normal to the axis of the winding core 3 is ≥ 40% of the cross-sectional area of ​​the button cell on the plane normal.

[0032] Specifically, when the electrode terminal 22 is used alone as the corrosion-resistant magnetic shielding part 7, the projected area of ​​the electrode terminal 22 on the normal plane of the core 3 axis is greater than or equal to 40% of the cross-sectional area of ​​the button cell on the normal plane, which can have a good magnetic shielding effect.

[0033] Referring to Figure 5, in some embodiments, the cover 2 includes a cylindrical cover;

[0034] The wound button battery also includes a second insulating ring 5 for sealing the side of the cylindrical cover and the housing 1; the cover 2 and / or the housing 1 are configured as the corrosion-resistant magnetic shielding part 7.

[0035] Specifically, in another embodiment of this application, the second insulating ring 5 serves to seal and connect the side of the cylindrical cover and the housing 1 in the wound button battery. The material of the second insulating ring 5 can be the same as that of the first insulating ring 23.

[0036] Specifically, the cover 2 and / or the housing 1 are configured as corrosion-resistant magnetic shielding parts 7, which are then assembled into the wound button battery to provide magnetic shielding and / or improve corrosion resistance.

[0037] In some embodiments, the cover 2 is configured as the corrosion-resistant magnetic shielding part 7, and the housing 1 is made of a second metal material.

[0038] In some embodiments, both the housing 1 and the cover 2 are configured as the corrosion-resistant magnetic shielding part 7.

[0039] Specifically, the second metal material is different from the first metal material. It can be a material with good corrosion resistance but no magnetic shielding function, such as 022Cr19Ni10 austenitic stainless steel.

[0040] In some embodiments, the operating voltage of the wound button battery is >4.4V.

[0041] In wound button batteries, austenitic and ferritic duplex stainless steel is used as the primary metal material, which can exhibit excellent corrosion resistance at a working voltage of 4.4V.

[0042] In some embodiments, the operating voltage of the wound button battery is ≥4.5V.

[0043] Furthermore, the wound button cell prepared using the first metallic material described in this application can achieve an operating voltage of 4.5V or higher without corrosion.

[0044] Another embodiment of the present invention provides a portable electroacoustic device, including an electromagnetic induction sound-generating device 6 and a wound button battery of the present invention, the wound button battery being used to power the electroacoustic device.

[0045] At least a portion of the cover and / or at least a portion of the casing of the wound button battery is a first metallic material with a relative magnetic permeability ≥50, which shields and dissipates the magnetic field generated by the current flowing through the winding core, thereby reducing the interference of the internal magnetic field of the wound button battery on the sound-generating device.

[0046] Referring to Figures 3, 4, 6, and 7, in some embodiments, the corrosion-resistant magnetic shielding part 7 is spaced between the electromagnetic induction sound-generating device 6 and the core 3.

[0047] Specifically, in the combination of the electromagnetic induction sound-generating device 6 and the wound button battery, by placing the corrosion-resistant magnetic shielding part 7 between the electromagnetic induction sound-generating device 6 and the winding core 3, it helps to better reduce the interference of the magnetic field generated by the current inside the winding core on the electromagnetic induction sound-generating device 6, thereby improving the overall sound quality.

[0048] The present invention will be further described below through specific embodiments.

[0049] Example 1

[0050] This embodiment illustrates a wound button battery disclosed in this invention, comprising:

[0051] The shell 1 and the metal substrate 21 are made of 022Cr19Ni5Mo3Si2N austenitic-ferritic duplex stainless steel (chromium content 19wt%) with a relative magnetic permeability of 60, with a thickness of 0.1mm. The outer diameter of the shell 1 is 12mm and the height is 5.6mm. The metal substrate 21 is a hollow disk with an outer diameter of 12mm and an opening diameter of 5mm.

[0052] The electrode terminal 22 is made of aluminum with a relative permeability of 1 by stamping. The terminal part is 0.35 mm thick and 4 mm in diameter, and the base part of the electrode terminal is 0.12 mm thick and 9 mm in diameter.

[0053] The metal substrate 21 and the electrode terminal 22 are connected as one unit by a first insulating ring 23 with a thickness of 0.05 mm;

[0054] A 90mAh capacity winding core 3, consisting of a positive electrode, a negative electrode, and a separator, is assembled into a housing 1. The positive electrode tab of the winding core is connected to the electrode terminal 22, and the negative electrode tab is connected to the housing 1.

[0055] Electrolyte is injected, and the housing 1 and metal substrate 21 are sealed by laser welding;

[0056] It is transformed into a battery.

[0057] Example 2

[0058] This embodiment illustrates a wound button battery disclosed in this invention, comprising:

[0059] The shell 1 and the metal substrate 21 are made of 022Cr19Ni5Mo3Si2N austenitic-ferritic duplex stainless steel (19wt% chromium content, 20% ferrite content) with a relative magnetic permeability of 60, with a thickness of 0.1mm, an outer diameter of 12mm, and a height of 5.6mm; the metal substrate is a hollow disk with an outer diameter of 12mm and an opening diameter of 5mm.

[0060] The electrode terminal 22 is also made of 022Cr19Ni5Mo3Si2N austenitic-ferritic duplex stainless steel with a relative permeability of 60 (chromium content 19wt%, ferrite ratio 20%), with a thickness of 0.1mm. The terminal part protrudes 0.23mm, the diameter of the protruding part is 4mm, and the diameter of the base part is 8mm.

[0061] The metal substrate 21 and the electrode terminal 22 are connected as one unit by a first insulating ring 23 with a thickness of 0.05 mm;

[0062] A 90mAh capacity winding core 3, consisting of a positive electrode, a negative electrode, and a separator, is assembled into a housing 1. The positive electrode tab of the winding core is connected to the electrode terminal 22, and the negative electrode tab is connected to the housing 1.

[0063] Electrolyte is injected, and the metal substrate 21 of the shell 1 and the cover is laser-welded to complete the sealing.

[0064] It is transformed into a battery.

[0065] Example 3

[0066] This embodiment illustrates a wound button battery disclosed in this invention, comprising:

[0067] The shell 1 and the metal substrate 21 are made of 022Cr19Ni10 austenitic stainless steel with a relative permeability of 1, and a thickness of 0.1mm. The outer diameter of the shell 1 is 12mm and the height is 5.6mm. The metal substrate 21 is a hollow disk with an outer diameter of 12mm and an opening diameter of 5mm.

[0068] The electrode terminal 22 is made of 022Cr19Ni5Mo3Si2N austenitic-ferritic duplex stainless steel with a relative magnetic permeability of 60 (chromium content 19wt%, ferrite ratio 20%), with a thickness of 0.1mm. The terminal part protrudes 0.23mm with a diameter of 4mm, and the base part has a diameter of 10mm.

[0069] The projected area of ​​electrode terminal 22 in the plane normal to the core axis is 69% of the cross-sectional area of ​​the button cell in the plane normal.

[0070] The metal substrate 21 and the electrode terminal 22 are connected as one unit by a first insulating ring 23 with a thickness of 0.05 mm;

[0071] A 90mAh capacity winding core 3, consisting of a positive electrode, a negative electrode, and a separator, is assembled into a housing 1. The positive electrode tab of the winding core 3 is connected to the electrode terminal 22, and the negative electrode tab is connected to the housing 1.

[0072] Electrolyte is injected, and the metal substrate 21 of the shell 1 and the cover is laser-welded to complete the sealing.

[0073] It is transformed into a battery.

[0074] Example 4

[0075] This embodiment illustrates a wound button battery disclosed in this invention, comprising:

[0076] The shell 1 and the metal substrate 21 are made of 022Cr19Ni10 austenitic stainless steel (relative magnetic permeability 1) by stamping, with a thickness of 0.1mm, an outer diameter of 12mm, and a height of 5.6mm; the metal substrate is a hollow disk with an outer diameter of 12mm and an opening diameter of 5mm.

[0077] The electrode terminal 22 is made of 022Cr19Ni5Mo3Si2N austenitic-ferritic duplex stainless steel (chromium content 19wt%, ferrite content 50%, relative permeability = 150) by stamping, with a thickness of 0.1mm. The terminal part protrudes 0.23mm, the diameter of the protruding part is 4mm, and the diameter of the base part is 9mm.

[0078] The projected area of ​​electrode terminal 22 in the plane normal to the core axis is 56% of the cross-sectional area of ​​the button cell in the plane normal.

[0079] The metal substrate 21 and the electrode terminal 22 are connected as one unit by a first insulating ring 23 with a thickness of 0.05 mm;

[0080] A 90mAh capacity winding core 3, consisting of a positive electrode, a negative electrode, and a separator, is assembled into a housing 1. The positive electrode tab of the winding core 3 is connected to the electrode terminal 22, and the negative electrode tab is connected to the housing 1.

[0081] Electrolyte is injected, and the metal substrate 21 of the shell 1 and the cover is laser-welded to complete the sealing.

[0082] It is transformed into a battery.

[0083] Example 5

[0084] This embodiment illustrates a wound button battery disclosed in this invention, comprising:

[0085] As shown in Figure 4, the shell 1 is made of 022Cr19Ni10 austenitic stainless steel (relative magnetic permeability 1) by stamping, with a thickness of 0.15mm, an outer diameter of 12mm, and a height of 5.2mm.

[0086] The cylindrical cover 2 is made of 022Cr19Ni5Mo3Si2N austenitic-ferritic duplex stainless steel (chromium content 19wt%, ferrite content 50%, relative magnetic permeability = 150) by stamping, with a thickness of 0.15mm, an outer diameter of 11.5mm, and a height of 5.2mm.

[0087] A 90mAh capacity winding core 3, consisting of a positive electrode, a negative electrode, and a separator, is assembled into a housing 1. The positive electrode tab of the winding core 3 is connected to the cover 2, and the negative electrode tab is connected to the housing 1.

[0088] Electrolyte is injected, and the cover 2 and the shell 1 are combined together between the second insulating ring 5. The shell is sealed to the cover by mechanically rolling the edge of the shell.

[0089] It is transformed into a battery.

[0090] Example 6

[0091] This embodiment illustrates a wound button battery disclosed in this invention, comprising:

[0092] As shown in Figure 4, the shell 1 is made of 022Cr19Ni5Mo3Si2N austenitic-ferritic duplex stainless steel (chromium content 19wt%, ferrite content 50%, relative magnetic permeability = 150) by stamping, with a thickness of 0.15mm, an outer diameter of 12mm, and a height of 5.2mm.

[0093] The cylindrical cover 2 is made of 022Cr19Ni10 austenitic stainless steel (relative magnetic permeability 1) by stamping, with a thickness of 0.15mm, an outer diameter of 11.5mm, and a height of 5.2mm;

[0094] A 90mAh capacity winding core 3, consisting of a positive electrode, a negative electrode, and a separator, is assembled into a housing 1. The positive electrode tab of the winding core 3 is connected to the cover 2, and the negative electrode tab is connected to the housing 1.

[0095] Electrolyte is injected, and the cover 2 and the shell 1 are combined together between the second insulating ring 5. The shell is sealed to the cover by mechanically rolling the edge of the shell.

[0096] It is transformed into a battery.

[0097] Comparative Example 1

[0098] This comparative example is used to illustrate a wound button battery disclosed in this invention, comprising:

[0099] The shell 1 and the metal substrate 21 are made of 022Cr19Ni10 austenitic stainless steel (relative magnetic permeability 1) by stamping, with a thickness of 0.1mm. The outer diameter of the shell 1 is 12mm and the height is 5.6mm. The metal substrate 21 is a hollow disk with an outer diameter of 12mm and an opening diameter of 5mm.

[0100] The electrode terminal 22 is made of aluminum with a relative permeability of 1 by stamping. The terminal part is 0.35 mm thick and 4 mm in diameter, and the base part of the electrode terminal is 0.12 mm thick and 9 mm in diameter.

[0101] The metal substrate 21 and the electrode terminal 22 are connected as one unit by a first insulating ring 23 with a thickness of 0.05 mm;

[0102] A 90mAh capacity winding core 3, consisting of a positive electrode, a negative electrode, and a separator, is assembled into a housing 1. The positive electrode tab of the winding core 3 is connected to the electrode terminal 22, and the negative electrode tab is connected to the housing 1.

[0103] Electrolyte is injected, and the metal substrate 21 of the shell 1 and the cover is laser-welded to complete the sealing.

[0104] It is transformed into a battery.

[0105] Comparative Example 2

[0106] This comparative example is used to illustrate a wound button battery disclosed in this invention, comprising:

[0107] As shown in Figure 4, the shell 1 is made of 022Cr19Ni10 austenitic stainless steel (relative magnetic permeability 1) by stamping, with a thickness of 0.15mm, an outer diameter of 12mm, and a height of 5.2mm.

[0108] The cylindrical cover 2 is also made of 022Cr19Ni10 austenitic stainless steel (relative magnetic permeability 1) by stamping, with a thickness of 0.15mm, an outer diameter of 11.5mm, and a height of 5.2mm;

[0109] A 90mAh capacity winding core 3, consisting of a positive electrode, a negative electrode, and a separator, is assembled into a housing 1. The positive electrode tab of the winding core 3 is connected to the cover 2, and the negative electrode tab is connected to the housing 1.

[0110] Electrolyte is injected, and the cover 2 and the shell 1 are combined together between the second insulating ring 5. The shell is sealed to the cover by mechanically rolling the edge of the shell.

[0111] It is transformed into a battery.

[0112] Comparative Example 3

[0113] This comparative example is used to illustrate a wound button battery disclosed in this invention, comprising:

[0114] The shell 1 and the metal substrate 21 are made of 022Cr19Ni10 austenitic stainless steel (relative magnetic permeability 1) by stamping, with a thickness of 0.1mm. The outer diameter of the shell 1 is 12mm and the height is 5.6mm. The metal substrate 21 is a hollow disk with an outer diameter of 12mm and an opening diameter of 5mm.

[0115] The electrode terminal 22 is made of permalloy Ni45-Fe55 (chromium content 0, relative permeability 4000) by stamping, with a thickness of 0.1mm. The terminal part protrudes by 0.23mm, the diameter of the protruding part is 4mm, and the diameter of the base part is 8mm.

[0116] The projected area of ​​electrode terminal 22 in the plane normal to the core axis is 44% of the cross-sectional area of ​​the button cell in the plane normal.

[0117] The metal substrate 21 and the electrode terminal 22 are connected as one unit by a first insulating ring 23 with a thickness of 0.05 mm;

[0118] A 90mAh capacity winding core 3, consisting of a positive electrode, a negative electrode, and a separator, is placed into the housing 1. The positive electrode tab of the winding core 3 is connected to the electrode terminal 22, and the negative electrode tab is connected to the housing 1.

[0119] Electrolyte is injected, and the metal substrate 21 of the shell 1 and the cover is laser-welded to complete the sealing.

[0120] It is transformed into a battery.

[0121] Comparative Example 4

[0122] This comparative example is used to illustrate a wound button battery disclosed in this invention, comprising:

[0123] As shown in Figure 4, the shell 1 is made of permalloy Ni45-Fe55 with 0% chromium content and a relative permeability of 4000 by stamping. It has a thickness of 0.15 mm, an outer diameter of 12 mm, and a height of 5.2 mm.

[0124] The cylindrical cover 2 is also made of permalloy Ni45-Fe55 with 0% chromium content and a relative permeability of 4000 by stamping. It has a thickness of 0.15 mm, an outer diameter of 11.5 mm, and a height of 5.2 mm.

[0125] A 90mAh capacity winding core 3, consisting of a positive electrode, a negative electrode, and a separator, is assembled into a housing 1. The positive electrode tab of the winding core 3 is connected to the cover 2, and the negative electrode tab is connected to the housing 1.

[0126] Electrolyte is injected, and the cover 2 and the shell 1 are combined together between the second insulating ring 5. The shell is sealed to the cover by mechanically rolling the edge of the shell.

[0127] It is transformed into a battery.

[0128] Performance testing

[0129] The following performance tests were performed on Examples 1-6 and Comparative Examples 1-4 prepared above:

[0130] Corrosion resistance test

[0131] Electrochemical corrosion resistance: The completed battery was charged at 25 degrees Celsius with 90mA 4.40V CCCV 2mA cutoff and discharged at 90mA 3.0V cutoff for 3 cycles; the battery was disassembled in a dry room and the inside of the casing 1 and the cover 2 were observed for corrosion and discoloration.

[0132] Magnetic shielding effect test

[0133] Aluminum wires were soldered to the positive and negative terminals of a button cell. The cell was charged with a 90mA 4.40V 2mA cut-off CCCV. Then it was placed in a zero magnetic space and discharged with a 200mA 0.01-second pulse current, one pulse per second. The peak magnetic field strength (absolute value) was measured vertically above / below the center of the top / bottom of the cell using a fluxgate gaussmeter with a sensitivity of 0.1mGs.

[0134] The test results are entered into Table 1.

[0135] Table 1

[0136] As can be seen from the test results in Table 1, the overall electrochemical corrosion resistance and magnetic shielding effect of Examples 1-6 are superior to those of Comparative Examples 1-4. Among them, compared with Comparative Examples 1-2, the magnetic field strength of Examples 1-6 is reduced by 30% or more on the side with the corrosion-resistant magnetic shielding part, and the magnetic shielding effect is significantly better than that of the prior art Comparative Examples 1-2. Compared with Comparative Examples 3-4, the inner surface of the metal parts of the casing of Comparative Examples 3-4 turns black after charging and discharging, that is, it is corroded by the electrolyte, which shows that it is not suitable as a lithium-ion battery casing.

[0137] Comparing Examples 1-2, when the casing, metal substrate, and electrode terminals of the wound button battery are all made of the first metal material, the magnetic shielding effect is good on both the positive and negative poles. Comparing Examples 2-4, when the first metal material is used only on the electrode terminals, while ensuring good magnetic shielding and corrosion resistance, the use of the first metal material is reduced, which helps to simplify the processing of the casing and metal substrate and reduce material costs. The test results of Examples 1-3 show that when the relative permeability of the first metal material is greater than or equal to 50, it has a good magnetic shielding effect.

[0138] In Comparative Examples 1 and 2, the shell, metal substrate, and electrode terminals are all made of a material with a relative magnetic permeability of 1. The magnetic fields on both the positive and negative sides are very strong, which can easily cause signal interference to the external structure. As shown in Comparative Examples 4 and 6, although permalloy as a magnetic shielding part also has a good magnetic shielding effect, it has serious problems in terms of resistance to electrolyte corrosion. In summary, the alloy used in this application has good magnetic shielding performance as well as good corrosion resistance.

[0139] Examples of electroacoustic devices with magnetic shielding

[0140] The button batteries in Examples 1-6 all adopt a structure in which the cover 2 is the positive electrode and the shell 1 is the negative electrode.

[0141] As shown in Figures 3 and 6, in embodiments 2-5 where the corrosion-resistant magnetic shielding part 7 is located on the positive pole side, the sound-generating device can be placed near the center position above the positive pole side (top cover);

[0142] As shown in Figures 4 and 7, in Embodiments 2-3 and 6, where the corrosion-resistant magnetic shielding part 7 is located on the negative pole side, the sound-generating device can be placed near the center of the lower part of the negative pole side (shell).

[0143] To further verify the corrosion resistance of the wound button cell made from the first metallic material (austenitic and ferritic duplex stainless steel) provided in this application under high voltage, a test was conducted at a voltage of 4.50V:

[0144] The test examples and comparative examples are set up as follows:

[0145] Comparative Example 5

[0146] This comparative example is used to illustrate a wound button battery disclosed in this invention, comprising:

[0147] The shell 1 and the metal substrate 21 are made of 022Cr19Ni10 austenitic stainless steel (relative magnetic permeability 1) by stamping, with a thickness of 0.1mm. The outer diameter of the shell 1 is 12mm and the height is 5.6mm. The metal substrate 21 is a hollow disk with an outer diameter of 12mm and an opening diameter of 5mm.

[0148] The electrode terminal 22 is made of 008Cr30Mo2 ferritic stainless steel (chromium content 30wt%, relative permeability = 500) by stamping, with a thickness of 0.1mm. The terminal part protrudes by 0.23mm, the diameter of the protruding part is 4mm, and the diameter of the base part is 8mm.

[0149] The projected area of ​​electrode terminal 22 in the plane normal to the core axis is 44% of the cross-sectional area of ​​the button cell in the plane normal.

[0150] The metal substrate 21 and the electrode terminal 22 are connected as one unit by a first insulating ring 23 with a thickness of 0.05 mm;

[0151] A 90mAh capacity winding core 3, consisting of a positive electrode, a negative electrode, and a separator, is assembled into a housing 1. The positive electrode tab of the winding core 3 is connected to the electrode terminal 22, and the negative electrode tab is connected to the housing 1.

[0152] Electrolyte is injected, and the metal substrate 21 of the shell 1 and the cover is laser-welded to complete the sealing.

[0153] It is transformed into a battery.

[0154] Comparative Example 6

[0155] This comparative example is used to illustrate a wound button battery disclosed in this invention, comprising:

[0156] The shell 1 is made of 008Cr30Mo2 ferritic stainless steel (chromium content 30wt%, relative magnetic permeability = 500, stamped), with a thickness of 0.15mm, an outer diameter of 12mm, and a height of 5.2mm;

[0157] The cylindrical cover 2 is also made of 008Cr30Mo2 ferritic stainless steel (chromium content 30wt%, relative magnetic permeability = 500) by stamping, with a thickness of 0.15mm, an outer diameter of 11.5mm, and a height of 5.2mm;

[0158] A 90mAh capacity core 3, consisting of a positive electrode, a negative electrode, and a separator, is placed into the housing 1. The positive electrode tab of the core 3 is connected to the cover 2, and the negative electrode tab is connected to the housing 1.

[0159] Electrolyte is injected, and the cover 2 and the shell 1 are combined together between the second insulating ring 5. The shell is sealed to the cover by mechanically rolling the edge of the shell.

[0160] It is transformed into a battery.

[0161] Fill in Table 2 with the test results of Example 1 and Comparative Examples 5-6.

[0162] Table 2

[0163] As can be seen from the test results in Table 2, compared with Comparative Examples 5-6, the inner surface of the metal parts of the battery casing of Comparative Examples 5-6 turned black after charging and discharging at a high voltage of 4.50V. This indicates that the wound button battery made with the magnetic shielding part including the first metal material provided in this application has better corrosion resistance under high voltage.

[0164] Secondly, although the wound button batteries prepared in Comparative Examples 5-6 have good magnetic shielding performance, their corrosion resistance under high voltage is poor. However, when the first metal material of austenitic and ferritic duplex stainless steel provided in Example 1 of this application is applied to the wound button battery, it can simultaneously exert the characteristics of magnetic shielding and high voltage corrosion resistance.

[0165] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A winding button cell, comprising a shell (1), a cover (2) and a winding core (3), the shell (1) and the cover (2) are assembled to form a closed cavity (4), and the winding core (3) is placed in the closed cavity (4); characterized in that, At least a portion of the cover (2) and / or at least a portion of the shell (1) are provided as corrosion-resistant magnetic shielding parts (7); the corrosion-resistant magnetic shielding parts (7) are made of a first metallic material with a relative magnetic permeability ≥50 and a chromium content >10wt%; The first metallic material is austenitic and ferritic duplex stainless steel.

2. The wound button cell of claim 1, wherein, The cover (2) includes a metal substrate (21), an electrode terminal (22), and a first insulating ring (23) for sealing the connection between the metal substrate (21) and the electrode terminal (22). The metal substrate (21) is welded to the housing (1). The electrode terminal (22) and / or the metal substrate (21) and / or the housing (1) are configured as the corrosion-resistant magnetic shielding part (7).

3. The wound button cell of claim 2, wherein, The electrode terminal (22) is configured as the corrosion-resistant magnetic shielding part (7), and the metal substrate (21) and the housing (1) are made of a second metal material; the projected area of ​​the electrode terminal (22) on the plane normal to the axis of the core (3) is ≥ 40% of the cross-sectional area of ​​the wound button battery on the plane normal to the axis of the core (3).

4. The wound button cell of claim 2, wherein, The electrode terminal (22), the metal substrate (21), and the housing (1) are all configured as the corrosion-resistant magnetic shielding part (7).

5. The wound button cell of claim 1, wherein, The cover (2) is a cylindrical cover; The wound button battery also includes a second insulating ring (5) for sealing the side of the cylindrical cover (2) and the housing (1); the cover (2) and / or the housing (1) are configured as the corrosion-resistant magnetic shielding part (7).

6. The wound button cell of claim 5, wherein, The cover (2) is configured as the corrosion-resistant magnetic shielding part (7), and the shell (1) is made of a second metal material.

7. The wound button cell of claim 5, wherein, Both the shell (1) and the cover (2) are provided with corrosion-resistant magnetic shielding parts (7).

8. A wound button battery according to any one of claims 1-7, characterized in that, The operating voltage of the wound button battery is >4.4V.

9. A wound button battery according to claim 8, characterized in that, The working voltage of the wound button battery is ≥4.5V.

10. An electroacoustic device, characterized in that, It includes an electromagnetic induction sound-generating device (6) and a wound button battery as claimed in any one of claims 1-9, the wound button battery being used to power the electroacoustic device.

11. An electroacoustic device according to claim 10, characterized in that, The corrosion-resistant magnetic shielding part (7) is spaced between the electromagnetic induction sound-generating device (6) and the winding core (3) of the button battery.

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