Pellet for injecting electrolyte and method for injecting electrolyte

Abstract

The pellet according to an embodiment of the present invention is a pellet for injecting an electrolytic solution configured to connect an electrolytic solution supply device that supplies the electrolytic solution and an opening formed on one side of a housing of a battery, and includes a hopper having a hollow structure, a hopper coupling portion coupled to the hopper, and a battery sealing portion configured to seal the opening portion, and the battery sealing portion may include a seal member configured to be in close contact with an inner surface of the housing of the battery.

Description

[Technical field]

[0001] The present invention relates to a pellet for electrolyte injection and a method for injecting electrolyte.

[0002] This application claims priority to Korean Patent Application No. 10-2022-0087614, filed on July 15, 2022, the entire contents of which are incorporated herein by reference in their entirety in the specification and drawings. [Background technology]

[0003] An electrolyte may be contained inside the secondary battery together with the electrode assembly. In manufacturing the secondary battery, a hole may be formed again for injecting the electrolyte after sealing of the housing constituting the secondary battery, or the electrolyte may be injected before sealing the housing, and then the housing may be sealed.

[0004] Regardless of which of these methods is used, it is necessary to prevent the electrolyte from leaking out of the secondary battery during the electrolyte injection process, and in order to prevent electrolyte leakage, it is necessary to tightly seal the connection between the electrolyte injection device and the secondary battery.

[0005] For example, in the case of a cylindrical secondary battery, an electrode assembly may be inserted through an opening on one side of a housing, and then electrolyte injection may be performed by inserting one side of a pellet configured to connect a device for supplying electrolyte to the secondary battery into the opening of the housing of the secondary battery, and supplying electrolyte using an electrolyte supply device connected to the other side of the pellet.

[0006] In this case, the end of the pellet inserted inside the opening of the housing may be in close contact with the bead portion formed on the housing. The inner surface of the bead portion formed by pushing inward around the housing may not form a completely flat surface, or other components may be located on the bead portion. Therefore, even if the end of the pellet is in close contact with the bead portion, the sealing at the connection point between the pellet and the secondary battery may be incomplete.

[0007] On the other hand, by forming the outer diameter or width of the end of the pellet to be substantially equal to the inner diameter or width of the housing, the pellet can be in close contact with the inner surface of the side wall of the housing to realize the sealing of the connection point. However, if the size of the end of the pellet is increased to strengthen the seal, the process of inserting the pellet into the secondary battery will inevitably become difficult. If the size of the end of the pellet is decreased to make it easier to insert the pellet, the seal will inevitably be weakened.

[0008] Therefore, the development of a pellet for injecting electrolyte having a structure capable of solving such problems is desired.

Summary of the Invention

Problems to be Solved by the Invention

[0009] The present invention has been made in view of the above problems, and its object is to provide a pellet that can not only facilitate the process of inserting the pellet for injecting electrolyte into the battery, but also strengthen the sealing performance at the connection point between the pellet and the battery.

[0010] However, the technical problems to be solved by the present invention are not limited to the above-mentioned problems at all, and other problems not mentioned should be clearly understood by those skilled in the art from the description of the invention described below.

Means for Solving the Problems

[0011] A pellet according to an embodiment of the present invention for solving the above-described problems is a pellet for injecting an electrolytic solution configured to connect an electrolytic solution supply device that supplies an electrolytic solution and an opening formed on one side of a housing of a battery, and includes a hopper having a hollow structure, a hopper coupling portion coupled to the hopper, and a battery sealing portion configured to seal the opening portion, and the battery sealing portion may include a seal member configured to be in close contact with an inner surface of the housing of the battery.

[0012] The seal member may have a hollow structure such that an internal space thereof communicates with an internal space of the hopper.

[0013] The battery sealing portion may be configured such that as it is pressed in a direction toward the battery, an end portion thereof is deformed outward and is in close contact with an inner surface of the housing of the battery.

[0014] The battery sealing portion may be configured such that an inner diameter or an inner width thereof increases as it advances in a direction away from the hopper.

[0015] The battery sealing portion may be configured such that its thickness decreases as it advances in a direction away from the hopper.

[0016] The battery sealing portion may be configured such that as it is pressed in a direction toward the battery, an end portion thereof slides outward on a beading portion provided on the housing of the battery and is in close contact with an inner surface of the housing above the beading portion.

[0017] The seal member may include a core protection portion configured to reduce a cross-sectional area of an internal space of the seal member through which the electrolytic solution passes.

[0018] The core protection portion may be configured to cross an internal space of the seal member.

[0019] The core protection part may be configured to pass through the central part of the internal space of the seal member.

[0020] The core protection part may be positioned so as to at least partially overlap with the winding center hole of the electrode assembly housed in the battery.

[0021] A method for injecting an electrolytic solution according to an embodiment of the present invention for solving the above-described problems is a method for injecting an electrolytic solution into a battery through an opening formed on one side of a housing of the battery, the method including: an insertion step of inserting a pellet for injecting the electrolytic solution into the opening; a placement step of placing a seal member provided on the pellet on a beading part provided on the housing; a close contact step of pressing the seal member toward the beading part so that an end portion of the seal member slides on the beading part and is in close contact with an inner surface of the housing above the beading part; and an injection step of injecting the electrolytic solution into the housing through the pellet.

[0022] The close contact step may be a step of pressing the seal member in a state where an end portion of the seal member is in contact with the beading part so that the end portion of the seal member is deformed outward, thereby bringing the seal member into close contact with the inner surface of the housing.

[0023] In the method for injecting an electrolytic solution of the present invention, the battery may include a current collector electrically connected to an electrode assembly housed in the housing, and the current collector may be positioned on the beading part.

[0024] In the method for injecting an electrolytic solution of the present invention, the current collector may be provided on the beading part discontinuously along the circumferential direction of the housing.

[0025] The liquid injection step may include a step of dispersing the liquid injection pressure of the electrolytic solution toward the winding center hole of the electrode assembly housed in the housing by using a core protection part configured to pass through the center part of the internal space of the seal member.

Advantages of the Invention

[0026] According to one aspect of the present invention, it is possible to achieve both the ease of the step of inserting the pellet for electrolytic solution injection into the battery and the strengthening of the sealing performance at the connection portion between the pellet and the battery.

[0027] In addition to these, the present invention can have various other effects. Regarding this, it will be described in the column of each implementation configuration, or the description will be omitted for effects that can be easily analogized by those skilled in the art.

[0028] The drawings attached to this specification illustrate the desirable embodiments of the present invention and are for the purpose of further understanding the technical idea of the present invention together with the content of the invention. Therefore, the present invention is not construed as being limited only to the matters described in the drawings.

Brief Description of the Drawings

[0029]

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Figure 10

Embodiments for Carrying Out the Invention

[0030] The terms and words used in this specification and the claims are not to be construed as being limited to the ordinary or dictionary meanings. The inventor interprets them in accordance with the meaning and concept corresponding to the technical idea of the present invention in accordance with the principle that the inventor can appropriately define the concept of the terms in order to explain the invention in the best way.

[0031] Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are only preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, there may be various equivalents and modifications that can replace them at the time of this application.

[0032] In the drawings, the size of each component or a specific part constituting the component is exaggerated, omitted, or schematically shown for ease of explanation and clarity. Therefore, the size of each component does not fully reflect the actual size. When it is recognized that a specific description of the known technology related to the present invention may obscure the gist of the present invention, the detailed description thereof is omitted.

[0033] For reference, in this specification, the terms indicating directions are relative terms that are based on the components shown in the attached drawings and can be changed according to the posture and position of the actual components.

[0034] On the one hand, in this specification, directional terms such as up, down, left, right, front, and back are used, but these terms are merely used for ease of explanation and it is obvious to those skilled in the art of the present invention that they may vary depending on the position of the object in question, the position of the observer, etc.

[0035] Referring to FIGS. 1 to 3, a pellet 1 according to an embodiment of the present invention will be described.

[0036] FIG. 1 is a diagram showing a state where a pellet according to an embodiment of the present invention is connected to a battery. FIG. 2 is a perspective view showing a seal member according to an embodiment of the present invention. FIG. 3 is a cross-sectional view showing a seal member according to an embodiment of the present invention.

[0037] Referring to FIGS. 1 to 3, the pellet 1 according to an embodiment of the present invention can be a pellet for injecting an electrolytic solution configured to connect an electrolytic solution supply device that supplies an electrolytic solution and an opening formed on one side of a housing 120 of a battery 100. In an embodiment of the present invention, the battery 100 to which the electrolytic solution is to be injected can be, for example, a cylindrical battery.

[0038] The pellet 1 may include a hopper 10 and a seal member 20. The hopper 10 may have a hollow structure so that the electrolytic solution supplied by the electrolytic solution supply device can pass through. That is, the hopper 10 can function as a connector that connects the electrolytic solution supply device and the battery 100 when injecting the electrolytic solution. The hopper 10 may include a metal material to ensure rigidity. However, the material of the hopper 10 is not limited thereto, and any material that maintains appropriate rigidity and has chemical resistance to the electrolytic solution passing through the inside can be applied to the hopper 10.

[0039] The seal member 20 may include a hopper coupling portion 21 coupled to the hopper 10 and a battery seal portion 22 configured to seal the open portion of the housing 120. The hopper coupling portion 21 may have a shape corresponding to one end of the hopper 10. The battery seal portion 22 may be configured to be in close contact with the inner surface of the housing 120 of the battery 100. The seal member 20 may include a material having flexibility so that electrolyte does not leak from the coupling location between the hopper 10 and the seal member 20 and the contact location between the seal member 20 and the battery 100.

[0040] The seal member 20 may include, for example, a rubber material. The seal member 20 may have a hollow structure such that its internal space communicates with the internal space of the hopper 10. The seal member 20 may be substantially cylindrical with a central portion being hollow.

[0041] The battery seal portion 22 according to an embodiment of the present invention may be configured such that as it is pressed in the direction toward the battery 100, its end portion is deformed outward and is in close contact with the inner surface of the housing 120.

[0042] For example, the battery seal portion 22 may be configured such that its inner diameter or inner width increases as it advances in the direction away from the hopper 10. The battery seal portion 22 may be configured such that its thickness decreases as it advances in the direction away from the hopper 10.

[0043] When such an inner diameter increasing structure of the battery seal portion 22 and / or a thickness decreasing structure of the battery seal portion 22 is applied, as the seal member 20 is pressed toward the battery 100, the end portion of the battery seal portion 22 can be firmly in close contact with the inner surface of the housing 120 of the battery 100 while being flexibly deformed. Therefore, the risk of electrolyte leakage in the process of injecting electrolyte into the battery 100 can be wiped out or reduced.

[0044] On the one hand, the pellet 1 may further include an additional seal member 30 configured to connect the electrolyte supply devices of the hopper 10. The additional seal member 30 can prevent the leakage of the electrolyte from the connection point between the electrolyte supply device and the hopper 10.

[0045] Next, with reference to FIGS. 4 and 5, a description will be given of the shape change accompanying the pressing of the seal member 20 according to the embodiment of the present invention in the direction toward the battery 100.

[0046] FIG. 4 is a diagram showing a connection structure between the seal member and the battery according to the embodiment of the present invention. FIG. 5 is a partially enlarged view of FIG. 4.

[0047] Referring to FIGS. 4 and 5, as the battery sealing portion 22 is pressed in the direction toward the battery 100, its end portion can be configured to slide outward of the battery 100 on the beading portion 121 provided on the housing 120 of the battery 100 and to be in close contact with the inner surface of the housing 120 above the beading portion 121.

[0048] The inner surface of the beading portion 121 formed by pressing inward around the housing 120 of the battery 100 may not form a completely flat surface, or other components may be located on the beading portion 121. Therefore, even if the end portion of the battery sealing portion 22 is brought into close contact with the beading portion 121, there is a possibility that the sealing at the contact interface between the battery sealing portion 22 and the beading portion 121 becomes incomplete. Therefore, as described above, when the end portion of the battery sealing portion 22 is configured to slide outward of the battery 100 on the beading portion 121 and to be in close contact with the inner surface of the housing 120 above the beading portion 121, the sealing performance can be further improved.

[0049] On the one hand, when the pellet 1 is pressed toward the battery 100, such movement shown by the battery sealing portion 22 can be obtained, for example, by the inner diameter increasing structure of the battery sealing portion 22 and / or the thickness decreasing structure of the battery sealing portion 22 as described above. On the other hand, the angle formed by the inner surface of the end portion of the battery sealing portion 22 with the vertical direction (the direction parallel to the Z-axis) can be, for example, approximately 10° to 30°. The angle formed by the outer surface of the end portion of the battery sealing portion 22 with the vertical direction (the direction parallel to the Z-axis) can be, for example, approximately 40° to 60°. Such angle conditions are the angle conditions in the state before the battery sealing portion 22 is pressed and deformed.

[0050] Next, with reference to FIGS. 6 to 8, the advantages when the battery sealing portion 22 according to the embodiment of the present invention is adhered onto the inner surface of the side wall of the housing 120 will be described in more detail.

[0051] FIG. 6 is a diagram showing a connection structure between a seal member and a battery according to an embodiment of the present invention, and shows a case where a current collector plate is provided on the battery. FIG. 7 is a partially enlarged view of FIG. 6. FIG. 8 is a plan view showing a battery provided with a current collector plate.

[0052] Referring to FIGS. 6 and 7, the pellet 1 according to the embodiment of the present invention can be applied, for example, to the battery 100 including a current collector 130 located on the beading portion 121 of the housing 120. The battery 100 may include an electrode assembly 110, a housing 120 that houses the electrode assembly 110, and a current collector 130 that is electrically connected to the electrode assembly 110 and is configured to be connected on the beading portion 121 of the housing 120. The current collector 130 can be coupled, for example, to the plain portion 111 provided on one surface of the electrode assembly 110. The current collector 130 may include a current collector hole 130a. The current collector hole 130a may be formed at a substantially central portion of the current collector 130. The current collector hole 130a may be formed at a position corresponding to the winding center hole of the electrode assembly 110.

[0053] When the current collector 130 is disposed on the beading portion 121 of the housing 120, unevenness may be formed on the upper surface of the beading portion 121 by the current collector 130. Further, when the current collector 130 is welded onto the beading portion 121, the flatness of the upper surface of the beading portion 121 may be further reduced by the weld bead.

[0054] Referring to FIG. 8, the current collector 130 may be discontinuously disposed, for example, on the beading portion 121 along the circumferential direction of the housing 120. When the battery 100 has such a structure, the flatness on the beading portion 121 may be further reduced.

[0055] Thus, when the flatness of the upper surface of the beading portion 121 is formed low, if an attempt is made to achieve sealing at the connection location between the pellet 1 and the battery 100 by the method of closely adhering the battery sealing portion 22 onto the beading portion 121, there is a risk that the sealing performance will deteriorate, and as a result, there is a risk that the electrolytic solution will leak during the liquid injection process. Therefore, when configured such that the end portion of the battery sealing portion 22 is closely adhered onto the surface of the inner wall of the side wall of the housing 120 above the beading portion 121, as in one embodiment of the present invention, it is possible to ensure even more improved sealing performance.

[0056] Next, with reference to FIGS. 9 and 10 in conjunction with FIG. 1, a seal member 20 having a structure different from that shown in FIG. 2 will be described.

[0057] FIG. 9 is a perspective view showing a seal member according to an embodiment of the present invention, and shows a structure in which a core protection portion is added to the seal member shown in FIG. 3. FIG. 10 is a plan view showing the seal member shown in FIG. 9.

[0058] Referring to FIGS. 9 and 10 in connection with FIG. 1, the seal member 20 may include a core protection portion 23. The core protection portion 23 may be configured to reduce the cross-sectional area of the internal space of the seal member 20 through which the electrolytic solution passes. For example, the core protection portion 23 may be configured to cross the internal space of the seal member 20. For example, the core protection portion 23 may be configured to pass through a substantially central portion of the internal space of the seal member 20. The core protection portion 23 may be positioned so as to at least partially overlap with the winding center hole of the electrode assembly 110 housed in the battery 100.

[0059] The core protection portion 23 may include a plurality of bridges 23a extending substantially radially outward from a substantially central portion of the internal space of the seal member 20. The core protection portion 23 may include a core cover 23b positioned at a substantially central portion of the internal space of the seal member 20. The core cover 23b may be configured to at least partially cover the winding center hole formed in the core of the electrode assembly 110 of the battery 100. The core cover 23b may be supported by the bridges 23a.

[0060] According to such a configuration of the seal member 20, when the electrolytic solution passing through the pellet 1 flows into the winding center hole formed in the core of the electrode assembly 110, a decrease in the flow rate and / or the flow velocity can occur. Alternatively, depending on the size and arrangement position of the bridges 23a and / or the core cover 23b of the core protection portion 23, it is possible to prevent the electrolytic solution from directly flowing into the winding center hole of the electrode assembly 110. Therefore, it is possible to prevent or minimize damage to the separator configured to wrap the inner wall surface of the winding center hole of the electrode assembly 110 due to the injection pressure of the electrolytic solution.

[0061] Next, a method for injecting an electrolytic solution according to an embodiment of the present invention will be described. When describing the method for injecting an electrolytic solution according to an embodiment of the present invention, FIGS. 1 to 10 of the present application will be referred to as a whole.

[0062] The method for injecting an electrolytic solution according to an embodiment of the present invention relates to a method for injecting an electrolytic solution into a battery 100 through an opening formed on one side of a housing 120 of the battery 100, and may include an insertion step, a placement step, a close contact step, and an injection step.

[0063] The insertion step may be a step of inserting a pellet 1 for injecting an electrolytic solution into the opening of the housing 120. The placement step may be a step of placing a seal member 20 provided on the pellet 1 on a beading portion 121 provided on the housing 120. The close contact step may be a step of pressing the seal member 20 toward the beading portion 121 so that an end portion of the seal member 20 slides on the beading portion 121 and is in close contact with an inner surface of the housing 120 above the beading portion 121. The injection step may be a step of injecting an electrolytic solution into the housing 120 through the pellet 1.

[0064] The close contact step may be a step of pressing the seal member 20 with an end portion of the seal member 20 in contact with the beading portion 121 so that the end portion of the seal member 20 is deformed outward, thereby bringing the seal member 20 into close contact with the inner surface of the housing 120.

[0065] In such a method for injecting an electrolytic solution according to an embodiment of the present invention, the battery 100 may include a current collector 130 configured to be electrically connected to an electrode assembly 110 housed in the housing 120. The current collector 130 may be located on the beading portion 121. The current collector 130 may be discontinuously provided on the beading portion 121 along the circumferential direction of the housing 120.

[0066] The injection step may be a step of dispersing the injection pressure of the electrolytic solution directed toward the winding center hole of the electrode assembly 110 housed in the housing 120 by using a core protection portion 23 configured to pass through the center portion of the internal space of the seal member 20.

[0067] As described above, the present invention has been explained by limited embodiments and drawings. However, the present invention is not limited thereto, and it goes without saying that various modifications and variations can be made within the scope equivalent to the technical idea of the present invention and the claims by those having ordinary knowledge in the technical field to which the present invention pertains.

Explanation of Signs

[0068] 1 pellet 10 hopper 20 seal member 21 hopper coupling part 22 battery sealing part 23 core protection part 23a bridge 23b core cover 100 battery 111 plain part 110 electrode assembly 120 housing 121 beading part 130 current collector 130a current collector hole

Claims

1. A pellet for injecting an electrolytic solution, configured to connect an electrolytic solution supply device that supplies an electrolytic solution and an opening formed on one side of a battery housing, including a hopper having a hollow structure, and including a hopper coupling portion coupled to the hopper and a battery sealing portion configured to seal the opening portion, wherein the battery sealing portion includes a seal member configured to be in close contact with an inner surface of the battery housing; The pellet including the above.

2. The seal member has a hollow structure such that its internal space communicates with the internal space of the hopper, and the pellet according to claim 1.

3. The battery sealing portion is configured such that as it is pressed in the direction toward the battery, an end portion thereof is deformed outward and is in close contact with an inner surface of the battery housing, and the pellet according to claim 1 or 2.

4. The battery sealing portion is configured such that an inner diameter or an inner width thereof increases as it advances in a direction away from the hopper, and the pellet according to claim 1 or 2.

5. The battery sealing portion is configured such that its thickness decreases as it advances in a direction away from the hopper, and the pellet according to claim 1 or 2.

6. The battery sealing portion is configured such that as it is pressed in the direction toward the battery, an end portion thereof slides outward on a beading portion provided on the battery housing and is in close contact with an inner surface of the housing above the beading portion, and the pellet according to claim 1 or 2.

7. The seal member includes a core protection portion configured to reduce a cross-sectional area of an internal space of the seal member through which the electrolytic solution passes, and the pellet according to claim 1 or 2.

8. The core protection portion is configured to cross an internal space of the seal member, and the pellet according to claim 7.

9. The core protection portion is configured to pass through a central portion of an internal space of the seal member, and the pellet according to claim 8.

10. The core protection portion is positioned to at least partially overlap a winding center hole of an electrode assembly housed in the battery, and the pellet according to claim 8.

11. A method for injecting an electrolytic solution into a battery through an opening formed on one side of a battery housing, comprising: an inserting step of inserting a pellet for injecting the electrolytic solution into the opening; a placing step of placing a sealing member provided on the pellet on a beading portion provided on the housing; a contacting step of pressing the sealing member toward the beading portion so that an end portion of the sealing member slides on the beading portion and comes into close contact with an inner surface of the housing above the beading portion; an injecting step of injecting the electrolytic solution into the housing through the pellet; The method for injecting an electrolytic solution includes the above steps.

12. The contacting step includes: pressing the sealing member with an end portion of the sealing member in contact with the beading portion so that the end portion of the sealing member is deformed outward, thereby bringing the sealing member into close contact with the inner surface of the housing. The method for injecting an electrolytic solution according to claim 11.

13. The battery includes a current collector electrically connected to an electrode assembly housed in the housing, The current collector is located above the beading portion. The method for injecting an electrolytic solution according to claim 11 or 12.

14. The current collector is: discontinuously provided above the beading portion along the circumferential direction of the housing. The method for injecting an electrolytic solution according to claim 13.

15. The injecting step includes: a step of dispersing the injection pressure of the electrolytic solution toward a winding center hole of the electrode assembly housed in the housing by using a core protection portion configured to pass through a central portion of an inner space of the sealing member. The method for injecting an electrolytic solution according to claim 11 or 12.

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