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EP-4016723-B1 - ELECTROLYTE INJECTION DEVICE AND ELECTROLYTE INJECTION METHOD USING THE SAME

EP4016723B1EP 4016723 B1EP4016723 B1EP 4016723B1EP-4016723-B1

Inventors

  • KIM, WON NYEON
  • KWON, SOON KWAN
  • LEE, BYEONG KYU
  • JUNG, SU TAEK

Dates

Publication Date
20260513
Application Date
20201111

Claims (8)

  1. An electrolyte injection device comprising: a base portion (210) configured to receive a preliminary battery cell (201) on an upper surface thereof; a movable pressing jig (220) attached to the base portion (210); and an electrolyte injection pipe (230) configured to inject an electrolyte into the preliminary battery cell, wherein the movable pressing jig (220) comprises a portion (321) configured to press the preliminary battery cell (201) in a direction perpendicular to an upper surface (204) and a lower surface (205) of an electrode assembly receiving portion (203) of the preliminary battery cell (201), wherein the movable pressing jig (220) comprises a pressing portion (321) configured to press the preliminary battery cell (201), and a support portion (322) configured to support the pressing portion (321), and wherein the pressing portion (321) has a surface (324) facing the preliminary battery cell (201), said surface (324) is a plane inclined with respect to an outer surface of the preliminary battery cell (201).
  2. The electrolyte injection device according to claim 1, wherein, in a state in which the movable pressing jig (220) presses the preliminary battery cell (201), the pressing portion (321) is in close contact with the preliminary battery cell (201) to press the preliminary battery cell (201), and the support portion (322)is spaced apart from the preliminary battery cell (201).
  3. The electrolyte injection device according to claim 1, wherein the movable pressing jig (220) is constituted by a plurality of unit movable pressing jigs (220A), and wherein the plurality of unit movable pressing jigs (220A) are disposed to be spaced apart from neighboring unit movable pressing jigs (220A) such that the electrolyte moves into the preliminary battery cell (201).
  4. The electrolyte injection device according to claim 1, wherein the electrolyte injection pipe (230) is configured to spray the electrolyte toward a portion of an outer periphery of the electrode assembly in which the movable pressing jig (220) is not disposed.
  5. An electrolyte injection method for manufacturing a battery cell using the electrolyte injection device according to any one of claims 1 to 5, the electrolyte injection method comprising: moving a movable pressing jig (220) in a first direction so as to increase a distance between the movable pressing jigs (220) in order to secure a position on which a preliminary battery cell (201) is disposed; positioning the preliminary battery cell (201) on a base portion (210); pressing the preliminary battery cell (201) by moving the movable pressing jig (220) in a second direction so as to narrow the distance between the movable pressing jigs (220); and injecting an electrolyte into the preliminary battery cell (201).
  6. The electrolyte injection method according to claim 5, wherein the movable pressing jig (220) comprises three or more pairs of unit movable pressing jigs (220A) facing each other with the preliminary battery cell (201) interposed therebetween.
  7. The electrolyte injection method according to claim 5, further comprising separating the preliminary battery cell (201) from the base portion (210) by moving again the movable pressing jig (220) in the first direction after the step of injecting the electrolyte.
  8. The electrolyte injection method according to claim 5, wherein, in the step of injecting the electrolyte, the electrolyte injection pipe (230) sprays the electrolyte toward a portion in which the movable pressing jig (220) does not press a battery cell.

Description

[Technical Field] This application claims the benefit of priority to Korean Patent Application No. 2019-0152102 filed on November 25, 2019. The present invention relates to an electrolyte injection device and an electrolyte injection method using the same, and more particularly to an electrolyte injection device including a structure capable of pressing and fixing a preliminary battery cell in order to prevent folding of a separator of an electrode assembly in the process of injecting an electrolyte for manufacturing a battery cell and an electrolyte injection method using the same. [Background Art] A lithium secondary battery, which is reusable and has high energy density, has attracted attention as a new energy source having environmentally friendly characteristics, since the lithium secondary battery is capable of remarkably reducing the use of fossil fuels and generates no byproducts as the result of using energy. The lithium secondary battery may be classified as a pouch-shaped battery cell made of a laminate sheet, a cylindrical battery cell made of a metal can, or a prismatic battery cell based on the kind and shape of a sheathing material. An electrode assembly is classified as a jelly-roll type electrode assembly, a stacked type electrode assembly, or a stacked/folded type or laminated/stacked type electrode assembly based on the shape thereof. The pouch-shaped lithium secondary battery is manufactured by receiving an electrode assembly and an electrolyte in a pouch-shaped battery case made of a laminate sheet, and then sealing an outer periphery of the battery case by a heating and pressing method. In connection therewith, FIG. 1 shows a part of a process of injecting an electrolyte into a conventional pouch-shaped battery cell, and FIG. 2 is a plan view showing a state in which an electrolyte injection pipe is omitted in FIG. 1. Referring to FIGS. 1 and 2, an electrolyte injection device includes a base portion 110, a jig 120, and an electrolyte injection pipe 130, and the jig 120 has a structure in which the jig 120 is fixed to the base portion 110 and is in a state that cannot be moved. Two pairs of jigs 120 facing each other based on a space in which a preliminary battery cell 101 is accommodated are fixedly disposed on the base portion 110, and an x-direction distance d2 between the jigs 120 is greater than a thickness d1 of the preliminary battery cell 110. Therefore, it is possible to easily insert and remove the preliminary battery cell 110 between the jigs. As described above, the jig is not in close contact with the preliminary battery cell but is located with spacing apart therefrom, and thus the jig is used as a cradle for the preliminary battery cell. In general, important considerations in the electrolyte injection process are the amount of electrolyte and the injection rate of the electrolyte. In order to increase the production rate, as the injection rate of the electrolyte is increased, the force exerted by the electrolyte to an electrode assembly is also increasing. Thus, a phenomenon in which an interface between an electrode and a separator is peeled off or a separator is folded into an electrode is increasing. Moreover, as shown in FIGS. 1 and 2, when the jig of the electrolyte injection device is disposed to be spaced apart from a pouch-shaped battery cell, the possibility of occurrence of the above problems is further increased. Therefore, there is a high necessity for a technology to prevent a phenomenon in which a separator is folded or an interface between an electrode and a separator is peeled off in the process of injecting an electrolyte into a pouch-shaped battery cell. Documents EP 3 457 464 A1 and KR 2016 0086196 A both relate to the injection of electrolyte in pouch-type battery cells. [Disclosure] [Technical Problem] The present invention has been made in view of the above problems, and it is an object of the present invention to provide an electrolyte injection device including a movable pressing jig including a portion for fixing and pressing a battery cell, and an electrolyte injection method using the same, in order to prevent an interface between an electrode and a separator from being peeled off or a separator from being folded during the electrolyte injection process. [Technical Solution] The subject matter of the present invention is solely defined in the appended claims. In order to accomplish the above object, an electrolyte injection device according to the present invention is defined in the appended claims. A device according to the present disclosure includes a base portion on which a preliminary battery cell is disposed on an upper surface thereof, a movable pressing jig attached to the base portion, and an electrolyte injection pipe configured to inject an electrolyte into the preliminary battery cell, wherein the movable pressing jig includes a portion configured to press the preliminary battery cell in a direction perpendicular to an upper surfac