Secondary battery
By setting a liquid storage bag on the roll core and setting a protrusion on the inner wall of the shell, the problem of electrolyte overflow is solved, and the stability of battery performance and energy density is improved.
Patent Information
- Application Number
- CN202422239891.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-12
- Publication Date
- 2025-08-01
- Estimated Expiration
- 2034-09-12
AI Technical Summary
During the process of injecting liquid in a buckle battery, the electrolyte is prone to overflow with the gas, resulting in a decrease in the battery's liquid retention capacity and affecting the battery's performance.
A liquid storage bag is set on the roll core and a protrusion is set on the inner wall of the shell to puncture the liquid storage bag during charging and discharging, release the electrolyte in the liquid storage bag, and replenish the battery electrolyte.
It avoids the loss of electrolyte during the vacuum stage, ensures stable battery performance, and improves the energy density and service life of the battery.
Smart Images
Figure CN223181366U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of batteries, in particular to a secondary battery. Background Art
[0002] With the rapid development of wireless communication technology and portable electronic devices, electronic devices such as TWS earphones and smart bracelets are widely welcomed by consumers due to their portability and comfort. To meet consumers' high requirements for wearing comfort and portability, the miniaturization and light weight of electronic devices and their supporting button cells have become particularly crucial. However, the reduction of the available space inside the electronic device and the increasing demand of users for battery endurance have formed a prominent contradiction.
[0003] In traditional technologies, in order to improve the energy density of the battery without increasing the volume of the electronic device, the method of increasing the active material inside the electrode is usually adopted. However, different from soft-pack batteries, button cells lack air bags, and during the liquid injection process, effective infiltration of the electrolyte must be achieved by repeatedly evacuating the air, which easily causes the electrolyte to overflow with the gas, reducing the liquid retention capacity of the battery and thus leading to a decline in battery performance. Summary of the Utility Model
[0004] Embodiments of the utility model provide a secondary battery to solve the problem of electrolyte loss during the vacuum pumping stage and avoid affecting battery performance.
[0005] Specifically, the utility model provides a secondary battery, including a housing, a wound core, a liquid storage bag, and a protrusion. The wound core is arranged inside the housing and is spaced from the side wall of the housing; the liquid storage bag is arranged on the wound core and is used for containing electrolyte; the protrusion is arranged on the inner wall of the housing and is opposite to the liquid storage bag for puncturing the liquid storage bag.
[0006] Optionally, the liquid storage bag is adhesively bonded to the wound core along the circumferential direction of the wound core.
[0007] Optionally, the ratio of the length of the liquid storage bag to the circumference of the wound core is 0.5 - 0.8.
[0008] Optionally, the difference between the height of the wound core and the height of the liquid storage bag is 1 mm - 2 mm.
[0009] Optionally, the length of the protrusion is 0.01 mm - 0.05 mm.
[0010] Optionally, the interval between the liquid storage bag and the inner wall of the housing is 0.08 mm - 0.14 mm.
[0011] Optionally, the end of the protrusion away from the inner wall of the housing is set as a tip.
[0012] Optionally, the number of the protrusions is one;
[0013] Alternatively, the number of the protrusions is plural, and the plural protrusions are uniformly arranged on the inner wall of the housing along the circumferential direction of the housing.
[0014] Optionally, when the electrolyte is accommodated in the liquid storage bag, the thickness of the liquid storage bag is 100 μm - 200 μm.
[0015] Optionally, the liquid storage bag is adhered to the core by a PET tape.
[0016] The beneficial effects of the present utility model are as follows:
[0017] In the secondary battery provided by the present utility model, since the liquid storage bag is arranged on the core, part of the electrolyte is stored in the liquid storage bag and will not be lost during the vacuum pumping stage; moreover, a protrusion for puncturing the liquid storage bag is arranged on the inner wall of the housing, so that in the later application, when the core expands during charge and discharge, the liquid storage bag moves towards the direction close to the protrusion until it contacts the protrusion and is punctured by the protrusion, releasing the electrolyte in the liquid storage bag to supplement the electrolyte for the secondary battery and avoiding the decline of battery performance. Description of the Drawings
[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required to be used in the description of the embodiments of the present utility model will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present utility model, and those of ordinary skill in the art can also obtain other drawings according to these drawings without creative efforts.
[0019] Figure 1 is a schematic cross-sectional view of a secondary battery in an embodiment of the present utility model;
[0020] Figure 2 is a schematic cross-sectional view of a secondary battery in an embodiment of the present utility model;
[0021] Figure 3 is a schematic structural view of a liquid storage bag in a secondary battery in an embodiment of the present utility model.
[0022] In the figure: 100, housing; 200, core; 300, liquid storage bag; 400, protrusion;
[0023] H1, height of the core; H2, height of the liquid storage bag; L, length of the protrusion; W, interval; A, thickness of the liquid storage bag. Detailed Embodiments
[0024] In order to make the technical problems, technical solutions and beneficial effects solved by the present utility model clearer and more understandable, the present utility model 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 only used to explain the present utility model and are not used to limit the present utility model.
[0025] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "radial", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is 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 should not be construed as a limitation to the present utility model. In the description of the present utility model, unless otherwise specified, the meaning of "a plurality of" is two or more.
[0026] In the description of the present utility model, 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 directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.
[0027] Figure 1 is a schematic cross-sectional view of a secondary battery in an embodiment of the present utility model, as Figure 1 shown, and with reference to Figures 2 to 3 , the embodiment of the present utility model provides a secondary battery, including a housing 100, a winding core 200, a liquid storage bag 300, and a protrusion 400. The winding core 200 is disposed in the housing 100 and is spaced apart from the side wall of the housing 100; the liquid storage bag 300 is disposed on the winding core 200, and the liquid storage bag 300 is used to accommodate electrolyte; the protrusion 400 is disposed on the inner wall of the housing 100 and is disposed opposite to the liquid storage bag 300 for puncturing the liquid storage bag 300.
[0028] In this embodiment, since the liquid storage bag 300 is provided on the core 200, part of the electrolyte is stored in the liquid storage bag 300 and will not be lost during the vacuum pumping stage. Moreover, a protrusion 400 for puncturing the liquid storage bag 300 is provided on the inner wall of the housing 100. So that in the later application, when the core 200 expands during charge and discharge, the liquid storage bag 300 moves towards the direction close to the protrusion 400 until it contacts the protrusion 400 and is punctured by the protrusion 400, releasing the electrolyte in the liquid storage bag 300 to supplement the electrolyte for the secondary battery and avoiding the decline of battery performance.
[0029] In an embodiment of the present utility model, the liquid storage bag 300 is made of a PP film or a film that does not react with the electrolyte. The liquid storage bag 300 is adhered to the core 200 by a PET tape, which can not only fix the liquid storage bag 300 on the core 200, but also prevent the core 200 from becoming loose.
[0030] Furthermore, the liquid storage bag 300 is adhered to the core 200 along the circumferential direction of the core 200, and the ratio of the length of the liquid storage bag 300 to the circumference of the core 200 is 0.5 - 0.8. If the ratio is too small, the liquid storage bag 300 is too short and the amount of electrolyte stored inside is small; if the ratio is too large, the liquid storage bag 300 is too long, the battery core is tightly wrapped, the expansion is affected, and it is not easy to be punctured; if the liquid storage bag 300 exceeds one circle, the PET tape will stick to the outside of the liquid storage bag 300, which is likely to cause the liquid storage bag 300 to be damaged in advance during the assembly process.
[0031] In an embodiment of the present utility model, the difference between the height H1 of the core 200 and the height H2 of the liquid storage bag 300 is 1 mm - 2 mm. That is to say, the height H1 of the liquid storage bag 300 is lower than the height H2 of the core 200, which can avoid affecting the height of the core 200 and further avoid affecting the energy density of the secondary battery.
[0032] As Figure 2 shown, in an embodiment of the present utility model, the length L of the protrusion 400 is 0.01 mm - 0.05 mm, so as to facilitate puncturing the liquid storage bag 300 when the core 200 expands. Furthermore, one end of the protrusion 400 away from the inner wall of the housing 100 is provided as a tip to reduce the difficulty of the protrusion 400 puncturing the liquid storage bag 300.
[0033] In an embodiment of the present utility model, the interval W between the liquid storage bag 300 and the inner wall of the housing 100 is 0.08 mm - 0.14 mm, so that the liquid storage bag 300 maintains a certain distance from the protrusion 400 in the initial state to avoid the protrusion 400 puncturing the liquid storage bag 300 during the assembly process.
[0034] In one embodiment of the present invention, there is one protrusion 400, and the protrusion 400 corresponds to the middle of the liquid storage bag 300, so that the electrolyte at both ends of the liquid storage bag 300 can flow out quickly after being punctured. Alternatively, there are multiple protrusions 400, and the multiple protrusions 400 are evenly arranged along the circumference of the housing 100 on the inner wall of the housing 100, so that the electrolyte in all parts of the liquid storage bag 300 can flow out quickly, while also avoiding the situation where a single protrusion 400 may not be able to puncture the liquid storage bag 300 in time.
[0035] like Figure 3 As shown, in one embodiment of the present invention, when the electrolyte is contained in the liquid storage bag 300, the thickness A of the liquid storage bag 300 is 100 μm-200 μm. If the liquid storage bag 300 is too thin, the amount of electrolyte stored therein is small; if the liquid storage bag 300 is too thick, the amount of electrolyte stored therein is large, resulting in some electrolyte being wasted and occupying space in the winding core 200, resulting in a reduction in the volume of the winding core 200 and affecting the energy density of the secondary battery.
[0036] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention, and should all be included in the scope of protection of the present invention.
Claims
1. A secondary battery, characterized in that, It includes a housing (100), a winding core (200), a liquid storage bag (300), and a protrusion (400). The winding core (200) is disposed inside the housing (100) and is spaced from the side wall of the housing (100); the liquid storage bag (300) is disposed on the winding core (200), and the liquid storage bag (300) is used to contain electrolyte; the protrusion (400) is disposed on the inner wall of the housing (100) and is opposite to the liquid storage bag (300) for piercing the liquid storage bag (300).
2. The secondary battery according to claim 1, wherein the liquid storage bag (300) is adhesively bonded to the winding core (200) along the circumferential direction of the winding core (200).
3. The secondary battery according to claim 2, wherein the ratio of the length of the liquid storage bag (300) to the circumference of the winding core (200) is 0.5 - 0.
8.
4. The secondary battery according to claim 2, wherein the difference between the height of the winding core (200) and the height of the liquid storage bag (300) is 1 mm - 2 mm.
5. The secondary battery according to claim 1, wherein the length of the protrusion (400) is 0.01 mm - 0.05 mm.
6. The secondary battery according to claim 5, wherein the interval between the liquid storage bag (300) and the inner wall of the housing (100) is 0.08 mm - 0.14 mm.
7. The secondary battery according to claim 1, wherein one end of the protrusion (400) away from the inner wall of the housing (100) is provided as a tip.
8. The secondary battery according to claim 1, wherein the number of the protrusions (400) is one; or, the number of the protrusions (400) is multiple, and the multiple protrusions (400) are uniformly disposed on the inner wall of the housing (100) along the circumferential direction of the housing (100).
9. The secondary battery according to claim 1, wherein when the electrolyte is contained in the liquid storage bag (300), the thickness of the liquid storage bag (300) is 100 μm - 200 μm.
10. The secondary battery according to claim 1, wherein the liquid storage bag (300) is adhesively bonded to the winding core (200) through a PET tape.