Pellets for electrolyte injection 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 injecting an electrolytic solution and a method for injecting an electrolytic solution.

[0002] This application claims priority based on Korean Patent Application No. 10-2022-0087614 filed on July 15, 2022, and all of the content disclosed in the specification and drawings of the application is incorporated into this application.

Background Art

[0003] An electrolytic solution can be accommodated inside a secondary battery together with an electrode assembly. When manufacturing a secondary battery, after temporarily completing the sealing of the housing constituting the secondary battery, holes may be formed again for injecting the electrolytic solution, or the electrolytic solution may be injected before the housing is sealed and then the housing may be sealed.

[0004] In any of these methods, it is necessary to prevent the electrolytic solution from leaking outside the secondary battery during the injection process of the electrolytic solution. In order to prevent leakage of the electrolytic solution, the connection part between the device for injection and the secondary battery needs to be tightly sealed.

[0005]

[0006] For example, in the case of a cylindrical secondary battery, after inserting the electrode assembly through an open part on one side of the housing, the electrolytic solution may be injected. By inserting one side of a pellet configured to connect a device for supplying the electrolytic solution and the secondary battery into the open part of the housing of the secondary battery and using an electrolytic solution supply device connected to the other side of the pellet to supply the electrolytic solution, the injection of the electrolytic solution can be performed.​In this case, the end of the pellet inserted into the opening of the housing may be in close contact with the beading formed in the housing. The inner surface of the beading, formed by pushing the housing inward, may not be perfectly flat, and other components may be located on top of the beading. Therefore, even if the end of the pellet is in close contact with the beading, the seal at the connection point between the pellet and the secondary battery may be incomplete.

[0007] On the other hand, a seal at the connection point can also be achieved by shaping the pellet so that its outer diameter or width is substantially equal to the inner diameter or width of the housing, thereby ensuring that the pellet is in close contact with the inner surface of the housing's side wall. However, increasing the size of the pellet's end to strengthen the seal inevitably makes the process of inserting the pellet into the secondary battery difficult, while decreasing the size of the pellet's end to facilitate insertion inevitably weakens the seal.

[0008] Therefore, the development of pellets for electrolyte injection with a structure that can resolve these problems is desirable. [Overview of the project] [Problems that the invention aims to solve]

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

[0010] However, the technical problems that this invention aims to solve are not limited in any way to those described above, and other problems not mentioned should be clearly understood by those skilled in the art from the description of the invention below. [Means for solving the problem]

[0011] A pellet according to one embodiment of the present invention for solving the above-mentioned problems is a pellet for electrolyte injection configured to connect an electrolyte supply device that supplies electrolyte and an open portion formed on one side of the 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 open portion, wherein the battery sealing portion may include a sealing member configured to be in close contact with the inner surface of the housing of the battery.

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

[0013] The battery sealing portion may be configured such that, when pressed toward the battery, its ends are deformed outward and come into close contact with the inner surface of the battery housing.

[0014] The battery sealing portion may be configured such that its inner diameter or inner width increases as it moves away from the hopper.

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

[0016] The battery sealing portion may be configured such that, as it is pressed toward the battery, its end slides toward the outside of the battery on a beading portion provided on the battery housing, and comes into close contact with the inner surface of the housing above the beading portion.

[0017] The sealing member may include a core protection portion configured to reduce the cross-sectional area of ​​the internal space of the sealing member through which the electrolyte passes.

[0018] The core protection portion may be configured to traverse the internal space of the sealing member.

[0019] The core protection portion may be configured to pass through the center of the internal space of the sealing member.

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

[0021] An electrolyte injection method according to one embodiment of the present invention for solving the above-mentioned problems is an electrolyte injection method for injecting electrolyte into a battery through an opening formed on one side of the battery housing, and may include: an insertion step of inserting an electrolyte injection pellet into the opening; a placement step of placing a sealing member provided on the pellet on a beading portion provided on the housing; a contact step of pressing the sealing member toward the beading portion so that the end of the sealing member slides on the beading portion and comes into close contact with the inner surface of the housing above the beading portion; and an injection step of injecting electrolyte into the inside of the housing through the pellet.

[0022] The aforementioned contact step may be a step of pressing the sealing member against the inner surface of the housing while the end of the sealing member is in contact with the beading portion, so that the end of the sealing member deforms outward, thereby bringing the sealing member into close contact with the inner surface of the housing.

[0023] In the electrolyte injection method 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 located above the beading portion.

[0024] In the electrolyte injection method of the present invention, the current collector may be provided discontinuously on the beading portion 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, and for these, they will be described in the column of each implementation configuration, or for effects that can be easily analogized by those skilled in the art, such descriptions will be omitted.

[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 to be construed as being limited only to the matters described in the drawings.

Brief Description of the Drawings

[0029] [Figure 1] It is a diagram showing a state where a pellet according to an embodiment of the present invention is connected to a battery. [Figure 2] It is a perspective view showing a seal member according to an embodiment of the present invention. [Figure 3] It is a cross-sectional view showing a seal member according to an embodiment of the present invention. [Figure 4] It is a diagram showing a connection structure between a seal member and a battery according to an embodiment of the present invention. [Figure 5] It is a partial enlarged view of FIG. 4. [Figure 6] It is a diagram showing a connection structure between a seal member and a battery according to an embodiment of the present invention, showing a case where a current collector plate is provided on the battery. [Figure 7] It is a partial enlarged view of FIG. 6. [Figure 8] This is a plan view showing a battery equipped with a current collector plate. [Figure 9] This is a perspective view showing a sealing member according to an embodiment of the present invention, wherein a core protection portion is added to the sealing member shown in Figure 3. [Figure 10] This is a plan view showing the sealing member shown in Figure 9. [Modes for carrying out the invention]

[0030] The terms and words used in this specification and in the claims are not to be interpreted in their ordinary or dictionary sense, but rather in a sense and concept corresponding to the technical idea of ​​the present invention, in accordance with the principle that inventors can appropriately define the concepts of terms themselves in order to best describe the invention.

[0031] Therefore, the embodiments described herein and the configurations shown in the drawings represent only preferred embodiments of the present invention and do not represent the entire technical concept of the invention. It should be understood that there are various equivalents and modifications that can be substituted for these embodiments at the time of filing this application.

[0032] In the figures, the size of each component or specific part of a component is sometimes exaggerated, omitted, or shown schematically for ease of explanation and clarity. Therefore, the size of each component does not fully reflect its actual size. Detailed explanations of known technologies related to the present invention are omitted if it is deemed that such explanations would ambiguously obscure the gist of the present invention.

[0033] For reference, in this specification, terms indicating direction are relative terms based on the components shown in the attached drawings, and can be modified depending on the orientation and position of the actual components.

[0034] On the other hand, while directional terms such as up, down, left, right, front, and back have been used in this specification, these terms are merely used for ease of explanation, and it will be obvious to those skilled in the art that they may vary depending on the position of the object in question, the observer's position, etc.

[0035] A pellet 1 according to one embodiment of the present invention will be described with reference to Figures 1 to 3.

[0036] Figure 1 shows a pellet connected to a battery according to one embodiment of the present invention. Figure 2 is a perspective view showing a sealing member according to an embodiment of the present invention. Figure 3 is a cross-sectional view showing a sealing member according to an embodiment of the present invention.

[0037] Referring to Figures 1 to 3, a pellet 1 according to one embodiment of the present invention may be a pellet for electrolyte injection configured to connect an electrolyte supply device that supplies electrolyte to an open portion formed on one side of the housing 120 of the battery 100. In the embodiment of the present invention, the battery 100 to which the electrolyte is injected may be, for example, a cylindrical battery.

[0038] The pellet 1 may include a hopper 10 and a sealing member 20. The hopper 10 may have a hollow structure to allow the electrolyte supplied by the electrolyte supply device to pass through. That is, the hopper 10 can function as a connector connecting the electrolyte supply device and the battery 100 when the electrolyte is injected. The hopper 10 may include a metal material to ensure rigidity. However, the material of the hopper 10 is not limited to this, and any material that maintains appropriate rigidity and has chemical resistance to the electrolyte passing through it can be used for the hopper 10.

[0039] The sealing member 20 may include a hopper coupling portion 21 that is coupled to the hopper 10 and a battery sealing 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 sealing portion 22 may be configured to be in close contact with the inner surface of the housing 120 of the battery 100. The sealing member 20 may include a flexible material to prevent electrolyte leakage from the coupling portion between the hopper 10 and the sealing member 20 and from the contact portion between the sealing member 20 and the battery 100.

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

[0041] According to an embodiment of the present invention, the battery sealing portion 22 may be configured such that, when pressed toward the battery 100, its end is deformed outward and comes into close contact with the inner surface of the housing 120.

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

[0043] When such an inner diameter increase structure and / or thickness reduction structure for the battery seal portion 22 is applied, as the sealing member 20 is pressed toward the battery 100, the end of the battery seal portion 22 can be flexibly deformed and firmly adhere to the inner surface of the housing 120 of the battery 100. Therefore, the risk of electrolyte leakage during the process of injecting electrolyte into the battery 100 can be eliminated or reduced.

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

[0045] Next, with reference to Figures 4 and 5, the change in shape that occurs when the sealing member 20 according to an embodiment of the present invention is pressed toward the battery 100 will be described.

[0046] Figure 4 shows a connection structure between a sealing member and a battery according to an embodiment of the present invention. Figure 5 is a partially enlarged view of Figure 4.

[0047] Referring to Figures 4 and 5, the battery sealing portion 22 may be configured such that, as it is pressed toward the battery 100, its end slides toward the outside of the battery 100 on the beading portion 121 provided on the housing 120 of the battery 100, and comes into 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 pushing the battery 100 inward around the housing 120, may not be a perfectly flat surface, and other components may be located on the beading portion 121. Therefore, even if the end of the battery seal portion 22 is in close contact with the beading portion 121, the seal at the contact interface between the battery seal portion 22 and the beading portion 121 may be incomplete. Thus, as described above, the seal can be further improved if the end of the battery seal portion 22 is configured to slide outward on the beading portion 121 toward the outside of the battery 100 and to be in close contact with the inner surface of the housing 120 above the beading portion 121.

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

[0050] Next, with reference to Figures 6 to 8, the advantages of the case in which the battery sealing portion 22 according to the embodiment of the present invention is in close contact with the inner surface of the side wall of the housing 120 will be described in more detail.

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

[0052] Referring to Figures 6 and 7, a pellet 1 according to an embodiment of the present invention is applicable to a battery 100 comprising, for example, a current collector 130 located on the beading portion 121 of a housing 120. The battery 100 may include an electrode assembly 110, a housing 120 housing the electrode assembly 110, and a current collector 130 electrically connected to the electrode assembly 110 and configured to be connected on the beading portion 121 of the housing 120. The current collector 130 may be coupled, for example, to a blank 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 substantially in the center of the current collector 130. The current collector hole 130a may be formed in a position corresponding to the winding center hole of the electrode assembly 110.

[0053] When the current collector 130 is placed on the beading portion 121 of the housing 120, the current collector 130 may create irregularities on the upper surface of the beading portion 121. Furthermore, when the current collector 130 is welded onto the beading portion 121, the weld bead may further reduce the flatness of the upper surface of the beading portion 121.

[0054] Referring to Figure 8, the current collector 130 may be discontinuously arranged on the beading portion 121 along the circumferential direction of the housing 120. If 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 low, if the battery sealing portion 22 is to be in close contact with the beading portion 121 in an attempt to seal the connection point between the pellet 1 and the battery 100, there is a risk that the sealing performance will be reduced, which may cause electrolyte leakage during the electrolyte injection process. Therefore, as in one embodiment of the present invention, when the end of the battery sealing portion 22 is configured to be in close contact with the inner wall surface of the side wall of the housing 120 above the beading portion 121, an even greater sealing performance can be ensured.

[0056] Next, referring to Figures 9 and 10 in conjunction with Figure 1, we will describe a sealing member 20 having a different structure from that shown in Figure 2.

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

[0058] Referring to Figures 9 and 10 in conjunction with Figure 1, the sealing 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 sealing member 20 through which the electrolyte passes. For example, the core protection portion 23 may be configured to traverse the internal space of the sealing member 20. For example, the core protection portion 23 may be configured to pass through approximately the center of the internal space of the sealing member 20. The core protection portion 23 may be positioned to at least partially overlap 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 substantially the center of the internal space of the sealing member 20. The core protection portion 23 may include a core cover 23b located substantially in the center of the internal space of the sealing 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] With this configuration of the sealing member 20, a decrease in flow rate and / or flow velocity can occur when the electrolyte passing through the pellet 1 flows into the winding central hole formed in the core of the electrode assembly 110. Alternatively, depending on the size and position of the bridge 23a and / or core cover 23b of the core protection part 23, it is possible to prevent the electrolyte from flowing directly into the winding central hole of the electrode assembly 110. Therefore, it is possible to prevent or minimize damage to the separator, which is configured to surround the inner wall surface of the winding central hole of the electrode assembly 110, due to the injection pressure of the electrolyte.

[0061] Next, a method for injecting an electrolyte according to one embodiment of the present invention will be described. In describing the method for injecting an electrolyte according to an embodiment of the present invention, Figures 1 to 10 of this application will be referenced in general.

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

[0063] The insertion step may be a step of inserting the pellet 1 for electrolyte injection into the open portion of the housing 120. The placement step may be a step of placing the sealing member 20 provided on the pellet 1 onto the beading portion 121 provided on the housing 120. The contact step may be a step of pressing the sealing member 20 toward the beading portion 121 so that the end of the sealing member 20 slides on the beading portion 121 and comes into close contact with the inner surface of the housing 120 above the beading portion 121. The liquid injection step may be a step of injecting the electrolyte into the housing 120 via the pellet 1.

[0064] The aforementioned contact step may be a step in which the seal member 20 is pressed against the inner surface of the housing 120 with the end of the seal member 20 in contact with the beading portion 121, so that the end of the seal member 20 deforms outward, thereby making the seal member 20 adhere tightly to the inner surface of the housing 120.

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

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

[0067] Although the present invention has been described above with reference to limited embodiments and drawings, it goes without saying that the present invention is not limited thereto, and that various modifications and variations can be made by persons with ordinary skill in the art to which the present invention pertains, within the equivalent scope of the technical concept and claims of the present invention. [Explanation of symbols]

[0068] 1 pellet 10 hoppers 20 sealing member 21 Hopper connection 22 Battery sealing section 23 Core protection section 23a Bridge 23b Core Cover 100 batteries 111 Plain section 110 Electrode assembly 120 Housing 121 Beading section 130 Current collector 130a Current collector hole

Claims

1. A pellet for electrolyte injection, configured to connect an electrolyte supply device that supplies electrolyte to an open portion formed on one side of the battery housing, A hopper having a hollow structure, The battery sealing portion includes a hopper coupling portion coupled to the hopper and a battery sealing portion configured to seal the opening, the battery sealing portion includes a sealing member configured to be in close contact with the inner surface of the battery housing, In pellets, including, The aforementioned battery sealing portion is A pellet configured such that, when pressed toward the battery, its end is deformed outward so as to adhere closely to the inner surface of the battery housing.

2. The sealing member is The pellet according to claim 1, wherein the internal space has a hollow structure such that it communicates with the internal space of the hopper.

3. The aforementioned battery sealing portion is The pellet according to claim 1 or 2, configured such that its inner diameter or inner width increases as it moves away from the hopper.

4. The aforementioned battery sealing portion is The pellet according to claim 1 or 2, configured such that its thickness decreases as it moves away from the hopper.

5. The aforementioned battery sealing portion is The pellet according to claim 1 or 2, wherein, as it is pressed toward the battery, its end slides toward the outside of the battery on a beading portion provided on the battery housing, and is configured to be in close contact with the inner surface of the housing above the beading portion.

6. The sealing member is The pellet according to claim 1 or 2, comprising a core protection portion configured to reduce the cross-sectional area of ​​the internal space of the sealing member through which the electrolyte passes.

7. The core protection section is The pellet according to claim 6, configured to traverse the internal space of the sealing member.

8. The core protection section is The pellet according to claim 7, configured to pass through the center of the internal space of the sealing member.

9. The core protection section is The pellet according to claim 7, which is positioned so as to at least partially overlap with the winding central hole of the electrode assembly housed in the battery.

10. A method for injecting electrolyte into a battery, wherein the electrolyte is injected into the battery through an opening formed on one side of the battery housing, The insertion step involves inserting a pellet for electrolyte injection into the aforementioned open portion, A placement step involves placing the sealing member provided on the pellet onto the beading portion provided on the housing, A contact step in which the sealing member is pressed toward the beading portion so that the end of the sealing member slides on the beading portion and comes into close contact with the inner surface of the housing above the beading portion, An injection step in which an electrolyte solution is injected into the inside of the housing via the pellets, In a method for injecting an electrolyte solution, The aforementioned contact step is, A method for injecting an electrolyte, comprising the step of pressing the sealing member against the inner surface of the housing while the end of the sealing member is in contact with the beading portion, so that the end of the sealing member deforms outward, thereby making the sealing member adhere tightly to the inner surface of the housing.

11. The battery comprises an electrode assembly housed within the housing and a current collector electrically connected thereto. The method for injecting an electrolyte according to claim 10, wherein the current collector is located above the beading portion.

12. The aforementioned current collector is The method for injecting an electrolyte according to claim 11, wherein the beading portion is provided discontinuously along the circumferential direction of the housing.

13. The aforementioned liquid injection step is, The method for injecting an electrolyte according to claim 10, further comprising the step of dispersing the injection pressure of the electrolyte toward the winding center hole of the electrode assembly housed in the housing using a core protection portion configured to pass through the center of the internal space of the sealing member.

Images