Lithium ion battery and application structure thereof

Abstract

The utility model relates to the field of lithium ion batteries, in particular to a lithium ion battery and an application structure of the lithium ion battery. Comprising a shell and a cover body arranged on the shell, and a battery roll core and electrolyte are arranged in the shell; the shell comprises a first shell and a second shell; the two ends of the first shell are open, one end of the first shell is provided with an annular inclined part which extends downwards and inclines inwards, and the cover body is arranged at the end, away from the inclined part, of the first shell; one end of the second shell is closed and the other end is open; the open end of the second shell is connected with the inclined part; wherein the opening diameter of the first shell is larger than that of the second shell. The lithium ion battery disclosed by the utility model is simple in structure, high in assembly efficiency and high in safety, and the yield of the lithium ion battery is improved.

Description

Technical Field

[0001] The utility model relates to the field of lithium ion batteries, in particular to a lithium ion battery and an application structure of the lithium ion battery. Background Art

[0002] With the continuous development of the wearable device market, wearable devices of various sizes and functions have put forward different requirements for energy storage devices. Steel-shell lithium-ion batteries with smaller size and higher energy density are increasingly widely used in wearable devices.

[0003] Currently, the steel-shell lithium-ion battery shells on the market are generally assembled or open at one end, and the open end needs to be matched with an end cover or another shell, and connected and sealed by welding or riveting.

[0004] Steel shells are generally seamed or seamless shells, and are made of commonly used iron-based alloys, such as stainless steel, carbon steel, etc. The plates are formed by bending, welding and stretching; if necessary, surface treatments such as electroplating and passivation are performed. Steel shells are currently widely used in the electronics industry, especially the lithium-ion battery industry, but the existing structure is generally a cylindrical opening mode, and the existing structure has deficiencies in production / manufacturing:

[0005] (1) The outer diameter of the battery core is close to the inner wall of the shell, and the battery core is approximately an ellipse. When inserting the battery core into the shell, there is a risk of interference with the shell opening and scratching the product, which may damage the battery core. At the same time, it may lead to failure of shell insertion, high defective rate and slow assembly efficiency.

[0006] (2) After the battery core is put into the shell, the core diaphragm will be hot-pressed for subsequent liquid injection and lid closing. Because the outer diameter of the battery core is close to the inner wall of the shell, in order to prevent the shell from being pressed during hot pressing, the outer diameter of the pressing head can only be reduced. This will cause the outermost diaphragm of the core to not be flattened, that is, the height of the outer diaphragm will affect the assembly of the cover and the shell. For example, the excess diaphragm that is not completely hot-pressed and flat is pressed at the joint between the shell opening and the end cover, or is attached to the inner wall of the shell top. During the circumferential seam welding, there will be a risk of cold welding, welding holes, or scalding or rupture of the inner wall diaphragm, resulting in a high defective rate.

[0007] (3) The existing shell space is limited. After injection, excess electrolyte overflows. There is no extra space to store the electrolyte. Multiple injections are required to ensure that the electrolyte soaks the core. When the end cover and the existing shell are matched, the core will be squeezed to cause excess electrolyte to overflow, resulting in explosion welding due to light refraction in the circumferential seam weld, which reduces production safety. Utility Model Content

[0008] The technical problem to be solved by the utility model is: in order to solve the technical problems of high defective rate, slow assembly efficiency and low safety of the existing lithium ion battery shell, the utility model provides a lithium ion battery with a simple structure, improved yield rate of the lithium ion battery, fast assembly efficiency and high safety.

[0009] The technical solution adopted by the utility model to solve the technical problem is: a lithium ion battery, comprising a shell and a cover body arranged on the shell, comprising: a battery coil core and an electrolyte are arranged in the shell;

[0010] The housing comprises a first housing and a second housing;

[0011] The first shell has openings at both ends, and one end of the first shell has a ring-shaped inclined portion extending downward and inclined inward, and the cover is disposed at one end of the first shell away from the inclined portion;

[0012] One end of the second shell is closed and the other end is open, and the open end of the second shell is connected to the inclined portion;

[0013] Wherein, the opening diameter of the first shell is larger than the opening diameter of the second shell.

[0014] Further, specifically, the wall thickness of the first shell and the second shell are both 0.1 mm to 0.5 mm.

[0015] Further, specifically, the height of the first shell is one third of the height of the shell.

[0016] Further, specifically, the materials of the first shell, the inclined portion and the second shell are all metal materials.

[0017] Further, specifically, the cover body and the first shell are connected by welding.

[0018] A lithium ion battery application structure comprises the lithium ion battery as described above and an electronic product.

[0019] The beneficial effects of the utility model are:

[0020] (1) The lithium-ion battery of the utility model has a simple structure. The opening diameter of the first shell is larger than the opening diameter of the second shell, so that there is a gap between the battery core and the inner wall of the first shell. When the battery core is inserted into the shell, the risk of crushing and scratching the battery core is reduced, and the yield rate is improved. In addition, due to the large shell diameter, the difficulty of inserting the battery core into the shell is reduced, and the assembly efficiency is improved.

[0021] (2) The opening diameter of the first shell is larger than the opening diameter of the second shell, and the inner cavity of the first shell is larger than the inner cavity of the second shell, which reduces the risk of damaging the shell during the hot pressing process. At the same time, the outer diameter of the hot pressing head can be increased, so that the diaphragm on the upper surface of the battery roll core can be completely covered during hot pressing, and the diaphragm can be flattened at the same time, which is convenient for the assembly of the cover body and the shell, and avoids the excess diaphragm that is not completely hot-pressed and flattened being pressed on the matching part between the shell opening and the end cover, or being attached to the inner wall of the top of the shell, which will cause the risk of cold welding, welding holes or scalding or breaking of the inner wall diaphragm during girth welding, and reduces the influence of the diaphragm on the girth welding, further improving the yield rate.

[0022] (3) The inner cavity of the first shell can store electrolyte overflowed due to hot pressing during the assembly process, and the circumferential weld can be welded without explosion due to light refraction, which is highly safe and reduces the number of electrolyte injections and vacuum pumping times, further improving assembly efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0024] Figure 1 It is a structural schematic diagram of the optimal embodiment of the utility model.

[0025] Figure 2 It is a schematic cross-sectional view of the assembly of the shell and the cover of the optimal embodiment of the utility model.

[0026] Figure 3 It is a schematic diagram of the explosion of the optimal embodiment of the utility model.

[0027] In the figure, 1 is a shell; 2 is a cover; 3 is a battery roll core; 11 is a first shell; 12 is a second shell; 13 is an inclined portion. DETAILED DESCRIPTION

[0028] Now the utility model is further described in detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the utility model in a schematic manner, and therefore only show the components related to the utility model.

[0029] In the description of the present utility model, it is necessary to understand that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.

[0030] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] like Figures 1 to 3 As shown, it is the optimal embodiment of the utility model, a lithium ion battery, including a shell 1 and a cover body 2 arranged on the shell 1, including: a battery roll core 3 and an electrolyte are arranged in the shell 1; the shell 1 includes a first shell 11 and a second shell 12; the first shell 11 is open at both ends, and one end of the first shell 11 has a ring-shaped inclined portion 13 extending downward and inclined inward, and the cover body 2 is arranged at one end of the first shell 11 and away from the inclined portion 13; the second shell 12 has one end closed and the other end open, and the open end of the second shell 12 is connected to the inclined portion 13; wherein the opening diameter of the first shell 11 is larger than the opening diameter of the second shell 12, in other words, the inner cavity space of the first shell 11 is larger than the inner cavity space of the second shell 12.

[0032] In the embodiment, the wall thickness of the first shell 11 and the second shell 12 are both 0.1 mm to 0.5 mm;

[0033] In the embodiment, the height of the first shell 11 is one third of the height of the shell 1, and the second shell 12 occupies a larger inner cavity of the entire shell 1 than the first shell 11, ensuring that the battery roll core located in the second shell 12 will not loosen, thereby playing the role of fixing the battery roll core.

[0034] In some embodiments, the height of the first shell is 1 mm to 5 mm, and the height of the first shell is set according to the overall height of the shell.

[0035] In the embodiment, the materials of the first shell 11, the inclined portion 13 and the second shell 12 are all metal materials, and the metal materials are iron-based alloys or aluminum alloys, including but not limited to stainless steel or carbon steel. The first shell 11, the inclined portion 13 and the second shell 12 are integrally formed by machining, stamping or cold heading.

[0036] In the embodiment, the cover body 2 and the first shell 11 are welded together, and the welding of the cover body 2 and the first shell 11 adopts but is not limited to ultrasonic welding, resistance welding, nanosecond welding and laser welding. In a specific embodiment, the cover body 2 and the first shell 11 are welded by laser annular seam.

[0037] A lithium-ion battery application structure includes the lithium-ion battery and an electronic product. The electronic product is a micro mobile wearable electronic product, including but not limited to TWS earphones, smart watches, smart glasses, and hearing aids.

[0038] In summary, the lithium-ion battery of the utility model has a simple structure. The opening diameter of the first shell 11 is larger than the opening diameter of the second shell 12, so that there is a gap between the battery core 3 and the inner wall of the first shell 11, which reduces the risk of crushing and scratching the battery core 3 when entering the shell, improves the yield rate, and because the shell entry diameter is large, the difficulty of entering the battery core 3 is reduced, and the assembly efficiency is improved; the opening diameter of the first shell 11 is larger than the opening diameter of the second shell 12, and the inner cavity of the first shell 11 is larger than the inner cavity of the second shell 12, which reduces the risk of crushing the shell 1 during the hot pressing process, and at the same time, the outer diameter of the hot pressing head can be increased, so that the battery core 3 can be completely pressed during hot pressing. The diaphragm fully covers the upper surface of the battery roll core 3 and can flatten the diaphragm at the same time, which is convenient for the assembly of the cover body 2 and the shell 1, and avoids the excess diaphragm that is not completely hot-pressed and flattened from being pressed on the opening of the shell 1 and the end cover, or attached to the top inner wall of the shell 1. The risk of cold welding, welding holes, or scalding or scalding of the inner wall diaphragm during circumferential welding is reduced, and the influence of the diaphragm on the circumferential welding is reduced, further improving the yield rate; the inner cavity of the first shell 11 can store the electrolyte overflowed due to hot pressing during the assembly process, and the circumferential welding can avoid explosion welding caused by light refraction, which has high safety, reduces the number of electrolyte injections and vacuum pumping times, and further improves the assembly efficiency.

[0039] Based on the above ideal embodiments of the utility model, the relevant staff can make various changes and modifications without departing from the technical concept of the utility model through the above description. The technical scope of the utility model is not limited to the content of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A lithium-ion battery, comprising a housing (1) and a cover (2) disposed on the housing (1), characterized in that: include: The housing (1) is provided with a battery coil core (3) and an electrolyte; The housing (1) comprises a first housing (11) and a second housing (12); The first shell (11) is open at both ends, and one end of the first shell (11) has a ring-shaped inclined portion (13) extending downward and tilting inward, and the cover (2) is arranged on one end of the first shell (11) away from the inclined portion (13); One end of the second shell (12) is closed and the other end is open, and the open end of the second shell (12) is connected to the inclined portion (13); Wherein, the opening diameter of the first shell (11) is larger than the opening diameter of the second shell (12).

2. The lithium-ion battery according to claim 1, characterized in that The wall thickness of the first shell (11) and the second shell (12) are both 0.1 mm to 0.5 mm.

3. The lithium ion battery according to claim 1 or 2, characterized in that: The height of the first shell (11) is one third of the height of the shell (1).

4. The lithium ion battery according to claim 1, characterized in that The first shell (11), the inclined portion (13) and the second shell (12) are all made of metal materials.

5. The lithium ion battery according to claim 4, characterized in that The cover body (2) and the first shell body (11) are connected by welding.

6. An application structure of a lithium ion battery, characterized in that: The invention comprises a lithium ion battery and an electronic product as claimed in any one of claims 1 to 5.

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