Apparatus for charging and discharging battery cells and method of charging and discharging battery cells using the apparatus

Abstract

The present technology relates to an apparatus for charging and discharging a battery cell, which is capable of suppressing a bump phenomenon of a plateau region of the battery cell during a formation process of the battery cell, and a method of charging and discharging the battery cell using the same.

Description

TECHNICAL FIELD

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2020-0165330, filed on December 1, 2020, and the entire contents of which are incorporated herein by reference.

[0002] The present application relates to an apparatus for charging and discharging a battery cell and a method of charging and discharging a battery cell using the same. BACKGROUND

[0003] Generally, a secondary battery can be classified into a cylindrical type, a prismatic type, a pouch type, etc. according to its shape. Here, since the pouch type secondary battery is formed by using a pouch outer material composed of a multi-layer film including a metal layer (a foil) and a synthetic resin layer coated on the upper and lower surfaces of the metal layer, the weight of the battery can be significantly reduced compared to the cylindrical or prismatic type using a metal can, which enables the battery to be lightweight and changed into various forms.

[0004] In such a pouch type secondary battery, an electrode assembly is placed in a stacked form. An electrode tab and an electrode lead are connected to the electrode assembly, and the electrode lead protrudes from the outer material of the pouch. Such an electrode lead is electrically connected to an external device through a contact, and power is supplied from the external device.

[0005] The pouch type secondary battery (hereinafter referred to as "battery cell") is manufactured through a process of assembling cells and a process of activating the battery, and in the battery activation step, the battery cell is mounted on a charging and discharging apparatus, and charging and discharging are performed as a necessary condition for activation. As described above, the process of performing predetermined charging / discharging using the charging and discharging apparatus for activating the battery cell is called a formation process.

[0006] In order to perform such a formation process of the battery cell, the battery cell should be properly mounted on the charging and discharging apparatus. That is, the electrode lead of the battery cell needs to be placed to contact the conductive part of the charging and discharging apparatus so that the electrode lead of the battery cell and the conductive part of the charging and discharging apparatus are electrically connected, and the electrically connected state should be maintained while charging and discharging are performed.

[0007] For this purpose, the charging and discharging apparatus of the secondary battery generally includes a plurality of pressing plates for fixing the battery cell. In a state in which each battery cell is inserted between two pressing plates, charging is performed by applying a current through the electrode lead of the battery cell while pressure is applied from both sides.

[0008] Similarly, by pushing the battery cell using the pressing plate, an increase in the thickness of the battery cell due to gas generation during the charging and discharging processes can be suppressed. At this time, the generated gas is collected in the airbag unit and then removed after the formation process. Here, the airbag unit is a portion of the pouch outer material that extends in a direction perpendicular to the electrode lead in the cell body portion that is pressed during the formation process, and can be cut later in the pouch outer material.

[0009] In addition, when the formation process is performed using a charging and discharging device according to the conventional art, the body portion of the battery cell that forms the thickness of the battery cell can be pressed by the pressing plate during the charging and discharging processes, but the cell platform region that is a sealed portion of the pouch case is not pressed by the pressing plate due to the step with the cell body portion.

[0010] As such, the internal pressure of the pouch case increases due to the gas generated during the charging and discharging processes, and the adhesive layer of the platform region of the battery cell is broken.

[0011] Figure 1 is a photograph showing a pouch-type battery cell that has undergone a formation process according to the conventional art, and Figure 2 is a schematic diagram showing a platform region of a pouch-type battery cell that has undergone a formation process according to the conventional art.

[0012] Reference Figures 1 to 2 Due to the internal adhesive layer of the cell platform region 1b being broken, a bulging phenomenon can occur in the pouch-type battery cell 1 that has undergone a formation process according to the conventional art. In addition, the pouch case can be composed of an outer insulation layer and an internal adhesive layer made of a polymer material, and a metal layer interposed between the outer insulation layer and the internal adhesive layer. Here, since the metal layer of the cell platform region 1b is exposed due to the above phenomenon, an insulation voltage defect is caused.

[0013] Therefore, since a serious problem can occur in the operation of such a battery cell, there is a need for a charging and discharging device and method that can suppress a bulging phenomenon of the platform region of a cell. SUMMARY

[0014] TECHNICAL PROBLEM

[0015] It is believed that the present invention solves at least some of the above problems. For example, an aspect of the present invention provides a device for charging and discharging a battery cell and a method of charging and discharging a battery cell using the device, which can suppress a bulging phenomenon of a platform region of a battery cell during a formation process of the battery cell.

[0016] TECHNICAL SOLUTION

[0017] The present invention provides an apparatus for charging and discharging a battery cell, which is capable of suppressing a bump phenomenon of a plateau region of the battery cell. In one example, the apparatus for charging and discharging a battery cell according to the present invention includes: first and second plates having a battery cell therebetween and pressing both surfaces of the battery cell; first and second holders connected to the first and second plates, respectively, and protruding at portions facing each other to contact a lead region of the battery cell; and first and second pressing pads at inner sides of the first and second holders to contact a plateau region of the battery cell.

[0018] In a specific example, an elastic pressing member is interposed between the first pressing pad and the first plate and between the second pressing pad and the second plate. In this way, the first and second pressing pads press the plateau region of the battery cell.

[0019] In one example, the elastic pressing member is a coil spring, a leaf spring, or rubber.

[0020] In one example, the first and second holders protrude to have a height greater than that in a state in which the first and second pressing pads are restored by the elastic pressing member.

[0021] In another example, the first and second holders have a relief or a grid of concaves on a surface contacting the lead region of the battery cell.

[0022] In yet another example, an additional elastic pressing member is interposed in at least one of a space between the first holder and the first plate and a space between the second holder and the second plate.

[0023] Further, the first and second pressing pads can have a strip shape having a size corresponding to 80% or more of a width and a length of the plateau region of the battery cell.

[0024] In a specific example, the first holder is connected to each of both ends of the first plate and is arranged perpendicular to the first plate, and the second holder is connected to each of both ends of the second plate and is arranged perpendicular to the second plate.

[0025] Further, the first pressing pad is mounted on both sides of the first plate by the elastic pressing member, respectively, and is mounted at an inner side of the first holder. Further, the second pressing pad is mounted on both sides of the second plate by the elastic pressing member, respectively, and is mounted at an inner side of the second holder.

[0026] In one example, the first plate and the second plate are made of an insulating material. Also, the first holder and the second holder are made of an electrically conductive material.

[0027] In one example, the first holder and the second holder have current terminals for current application that contact and are electrically connected to the lead region of the battery cell, and the first holder and the second holder have voltage terminals for voltage detection that contact and are electrically connected to the lead region of the battery cell.

[0028] Also, the present application provides a method of charging and discharging a battery cell using the above-described device for charging and discharging a battery cell.

[0029] Advantageous Effects

[0030] The device for charging and discharging a battery cell according to the present application and the method of charging and discharging a battery cell using the device, by including the first pressing pad and the second pressing pad that press the plateau region of the battery cell, are capable of suppressing the bulging phenomenon of the plateau region of the battery cell during the formation process of the battery cell. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 is a photograph showing a pouch-type battery cell that has undergone a formation process according to a conventional art.

[0032] Figure 2 is a schematic diagram showing the plateau region of a pouch-type battery cell that has undergone a formation process according to a conventional art.

[0033] Figure 3 is a schematic diagram showing a device for charging and discharging a battery cell according to one embodiment of the present application.

[0034] Figure 4 is a close-up view of a surface of a holder in a device for charging and discharging a battery cell according to one embodiment of the present application.

[0035] Figure 5 is a diagram schematically showing a portion to which a pressing pad is applied when a battery cell is charged and discharged using a device for charging and discharging a battery cell according to one embodiment.

[0036] Figure 6 is a schematic diagram showing a device for charging and discharging a battery cell according to one embodiment of the present application. DETAILED DESCRIPTION

[0037] Because the inventive concept allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present application to particular forms disclosed, and it is understood that all changes, equivalents, and substitutes included in the spirit and scope of the present application are included.

[0038] In this application, it is understood that terms such as "include" or "have" are intended to indicate existence of described features, numbers, steps, operations, components, parts, or combinations thereof, and these terms are not intended to preclude presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. Also, when a part such as a layer, a film, a region, a plate, or the like is referred to as "on" another part, it can be directly on the other part, or intervening another part can be present therebetween. On the other hand, when a part such as a layer, a film, a region, a plate, or the like is referred to as "under" another part, it can be directly under the other part, or intervening another part can be present therebetween. In addition, "disposed on" in this application can include both a case disposed at a bottom and a case disposed at a top.

[0039] The present application relates to an apparatus for charging and discharging a battery cell and a method of charging and discharging a battery cell using the same.

[0040] When a formation process is performed using a charging and discharging apparatus according to a conventional technique, a body portion of a battery cell forming a thickness of the battery cell can be pressed by a pressing plate during a charging and discharging process, but a cell platform region, which is a sealed portion of a pouch case, is not pressed by the pressing plate due to a step with the cell body portion. In this way, an internal pressure of the pouch case increases due to gas generated during the charging and discharging process, and a bonding layer of the platform region of the battery cell is broken. In addition, the pouch case can be composed of an outer insulation layer and an inner bonding layer made of a polymer material, and a metal layer interposed between the outer insulation layer and the inner bonding layer. Here, since the metal layer of the cell platform region is exposed due to the above phenomenon, an insulation voltage defect is caused.

[0041] In this way, the present application provides an apparatus for charging and discharging a battery cell and a method of charging and discharging a battery cell using the same, which is capable of suppressing a bulging phenomenon of a platform region of a battery cell during a formation process of the battery cell. Specifically, the apparatus for charging and discharging a battery cell and the method of charging and discharging a battery cell using the same according to the present application, by including a first pressing pad and a second pressing pad that press a platform region of a battery cell, are capable of suppressing a bulging phenomenon of a platform region of a battery cell during a formation process of the battery cell.

[0042] Hereinafter, a device for charging and discharging a battery cell according to the present application and a method of charging and discharging a battery cell using the same will be described in detail.

[0043] In one example, a device for charging and discharging a battery cell according to the present application includes a first plate and a second plate having a battery cell therebetween and squeezing two surfaces of the battery cell, a first holder and a second holder connected to the first plate and the second plate, respectively, and protruding at portions facing each other to contact a tab area of the battery cell, and a first squeezing pad and a second squeezing pad at inner sides of the first holder and the second holder to contact a platform area of the battery cell. In a specific example, an elastic squeezing member is interposed between the first squeezing pad and the first plate and between the second squeezing pad and the second plate. As such, the first squeezing pad and the second squeezing pad can squeeze the platform area of the battery cell.

[0044] Generally, in a formation process, a battery cell can be bulged due to gas generation or expansion of positive and negative electrode plates. At this time, the first plate and the second plate prevent the bulging by squeezing the battery cell during the formation process. Specifically, in the device for charging and discharging a battery cell according to the present application, the first plate and the second plate are arranged at regular intervals and are configured to be movable so that the intervals can be increased or decreased. That is, the battery cell is arranged between the first plate and the second plate, and the first plate and the second plate are moved in a direction of squeezing the two surfaces of the battery cell, thereby squeezing the battery cell.

[0045] Further, the first plate and the second plate are connected in a manner allowing translational motion along a shaft extending in one side, a gear is connected to one end of the shaft, and a driving motor can be connected to the gear. Here, any mechanical combination can be used as long as it has a driving mechanism capable of moving the first plate and the second plate in a direction of squeezing the battery cell.

[0046] The battery cell is a pouch-type unit cell, and an electrode assembly having a positive electrode / separator / negative electrode structure is embedded in an outer material of a laminate sheet in a state of being connected to electrode tabs formed on an outer side of the outer material. The electrode tabs can be led to an outer side of the sheet and can extend in the same or opposite directions to each other.

[0047] For convenience of explanation, the drawings of the present application merely show a pouch-type battery cell having a pair of electrode tabs drawn out in opposite directions, but the battery cell applied to the battery module according to the present application is not particularly limited thereto, and a pair of electrode tabs can be drawn out in the same direction. Here, the pouch-type battery cell can include an airbag unit.

[0048] In one example, the first plate and the second plate can be made of a metal material having high mechanical rigidity, so that the first plate and the second plate are not deformed under high heat and high pressure. For example, aluminum or stainless steel can be used. However, the material of the extruded plate is not limited to a metal material, and the extruded plate can also be made of a reinforced plastic, a reinforced ceramic, or tempered glass.

[0049] In one example, the battery cell including the air cell unit in the inactive state is transferred by a pickup device and then inserted into the space between the first plate and the second plate.

[0050] In one example, the first holder and the second holder contact the lead region of the battery cell, thereby applying a current to the battery cell and detecting a voltage. Here, the lead region of the battery cell refers to the electrode lead. In particular, since the first holder and the second holder are connected to the first plate and the second plate, respectively, the first holder and the second holder are configured to be integrally moved when the first plate and the second plate move. In a specific example, the first holder and the second holder have a structure connected to the first plate and the second plate and protruding at a portion facing each other to contact the lead region of the battery cell. The first holder can have a structure connected to each of both ends of the first plate and arranged perpendicular to the first plate, and the second holder can have a structure connected to each of both ends of the second plate and arranged perpendicular to the second plate. At this time, the first holder and the second holder can be arranged in a region facing each other and easily fix the lead region of the battery cell.

[0051] In one example, the first holder and the second holder have a current terminal for current application that contacts and is electrically connected to the lead region of the battery cell, and the first holder and the second holder have a voltage terminal for voltage detection that contacts and is electrically connected to the lead region of the battery cell. The first holder and the second holder can themselves be composed of the current terminal and the voltage terminal. At this time, the first holder and the second holder can be made of an electrically conductive member. For example, the first holder and the second holder can be made of aluminum, copper, or nickel, for example, nickel or copper having excellent electrical conductivity, or an alloy of copper and nickel. However, the present application is not limited thereto.

[0052] In another example, the first holder and the second holder can further include a current terminal and a voltage terminal as described above. In particular, the current terminal and the voltage terminal are configured to electrically contact the lead region of the battery cell when the first plate and the second plate extrude the battery cell. In addition, a cable for supplying a current terminal can be connected to the current terminal and the voltage terminal.

[0053] In another example, the first holder and the second holder have a grid of protrusions or depressions on a surface that contacts the tab area of the battery cell. Specifically, the fixing force of the first holder and the second holder on the tab area of the battery cell can be enhanced by forming a grid on the surface of the first holder and the second holder. In the present invention, the grid means a grid or a checkered pattern, and is a general term indicating a form in which two or more parallel patterns cross each other. In a specific example, the average depth of depression or the average height of protrusion of the grid of protrusions or depressions formed on the surface of the first holder and the second holder is in the range of 0.001 mm to 1 mm. For example, the average depth of depression or the height of protrusion of the grid is in the range of 0.001 mm to 0.1 mm, 0.001 mm to 0.01 mm, 0.01 mm to 0.1 mm, or 0.01 mm to 0.05 mm. In the present invention, by forming a very low level of depression or protrusion pattern, it is possible to enhance the fixing force with the tab area while not deteriorating the mechanical properties of the tab area.

[0054] In one example, the device for charging and discharging a battery cell according to the present invention includes first and second pressing pads at the inner side of the first and second holders and contacting the platform area of the battery cell. The first and second pressing pads are used to suppress the bulging phenomenon of the platform area of the battery cell during the formation process of the battery cell and to prevent pouch deformation in the platform area of the battery cell. Further, elastic pressing members are interposed between the first pressing pad and the first plate and between the second pressing pad and the second plate. In a specific example, the first pressing pad is mounted on both sides of the first plate by the elastic pressing members and at the inner side of the first holder, respectively. Further, the second pressing pad is mounted on both sides of the second plate by the elastic pressing members and at the inner side of the second holder, respectively.

[0055] In one example, the elastic pressing member is a coil spring, a leaf spring, or rubber. For example, the elastic pressing member can be a coil spring. The coil spring is a spring having a force resisting compression and refers to a compression spring.

[0056] In one example, since the first and second pressing pads are connected to the first and second plates and the elastic pressing members, respectively, the first and second pressing pads can be integrally moved when the first and second plates are moved. That is, when the first and second plates press the body area of the battery cell, the first and second pressing pads press the platform area of the battery cell. At this time, the first and second pressing pads are elastically pushed into the elastic pressing members, and the impact when contacting the platform area of the battery cell can be absorbed, and the contact state can be stably maintained due to the application of the elastic restoring force of the elastic pressing members.

[0057] In another example, the first and second clamps protrude to have a height greater than that in a state in which the first and second pressing pads are restored by the elastic pressing member. In a specific example, the first and second clamps protrude to have a height greater than that in a state in which the first and second pressing pads are restored by the elastic pressing member by about 10% or more. For example, when the height in a state in which the first and second pressing pads are restored by the elastic pressing member is 20 mm, the height of the protruding structure of the first and second clamps becomes 22 mm. This is to prevent the first and second clamps from being separated from the lead region of the battery cell when a bulging phenomenon occurs in the platform region during a formation process of the battery cell.

[0058] The first and second pressing pads can have a strip shape having a size corresponding to 80% or more of the width and length of the platform region of the battery cell. For example, the width and length of the first and second pressing pads can correspond to the width and length of the platform region of the battery cell. This is to effectively perform pressing by increasing the area in which the first and second pressing pads directly contact the platform region of the battery cell. Also, as a portion that directly contacts the platform region of the battery cell, the first and second pressing pads can be made of an epoxy material.

[0059] Also, the first and second pressing pads can be integrally formed with the first and second clamps, respectively, but not form a step in the lead region and the platform region of the battery cell, which is not desirable. Also, a bulging phenomenon can occur in the platform region. As such, in the case in which the first and second pressing pads are integrally formed with the first and second clamps, respectively, the first and second clamps can be separated from the lead region of the battery cell.

[0060] In another example, also in the apparatus for charging and discharging a battery cell according to the present application, the elastic pressing members are interposed between the first pressing plate and the first plate and between the second pressing plate and the second plate. For example, in the apparatus for charging and discharging a battery cell according to the present application, the elastic pressing members are interposed between the second clamps and the second plate.

[0061] In a specific example, when the first and second plates press the battery cell, the second clamps connected to the elastic pressing members are elastically pushed in, and when contacting the lead region of the battery cell, an impact can be absorbed, and a contact state can be stably maintained due to the application of the elastic restoring force of the elastic pressing members. Also, the elastic coefficient of the elastic pressing members placed between the second clamps and the second plate can be different from the elastic coefficient of the elastic pressing members placed between the pressing pads and the plates.

[0062] With this configuration, the device for charging and discharging a battery cell according to the present application can easily fix the lead wire region and suppress the bulging phenomenon of the tab region of the battery cell during the formation process of the battery cell.

[0063] Further, the present application provides a method for forming a battery cell using the above-described device for forming a battery cell. In a specific example, the method of forming a battery cell according to the present application can be performed after interposing the battery cell in the device for charging and discharging a battery cell. The method of charging and discharging a battery cell according to the present application, by including the first and second pressing pads that press the tab region of the battery cell, can suppress the bulging phenomenon of the tab region of the battery cell during the formation process of the battery cell. For example, the pressure range of the first and second pressing pads can be in the range from 5 mm to 15 mm, and the battery cell can be pressed to about 10 mm on average.

[0064] Hereinafter, various forms of a device for charging and discharging a battery cell that can suppress the bulging phenomenon of the tab region of the battery cell during the formation process of the battery cell will be described with reference to the accompanying drawings.

[0065] (First Embodiment)

[0066] Figure 3 is a schematic view showing a device for charging and discharging a battery cell according to one embodiment of the present application, Figure 4 is an enlarged view of a surface of a holder in a device for charging and discharging a battery cell according to one embodiment of the present application, and Figure 5 is a view schematically showing a portion to which a pressing pad is applied when charging and discharging a battery cell using a device for charging and discharging a battery cell according to one embodiment.

[0067] Reference Figures 3 to 5, the device 100 for charging and discharging a battery cell includes: first and second plates 111 and 112 having a battery cell therebetween and pressing both surfaces of the battery cell; first and second holders 121 and 122 connected to the first and second plates 111 and 112, respectively, and protruding at portions facing each other to contact a lead region la of the battery cell 1; and first and second pressing pads 131 and 132 located at inner sides of the first and second holders 121 and 122 to contact a platform region lb of the battery cell 1. In particular, in the device 100 for charging and discharging a battery cell according to the present application, elastic pressing members 140 are interposed between the first pressing pad 131 and the first plate 111 and between the second pressing pad 132 and the second plate 112. In this way, the first and second pressing pads 131 and 132 can easily press the platform region lb of the battery cell 1.

[0068] During formation, the battery cell can be bulged due to gas generation or expansion of the positive and negative electrode plates. At this time, the first and second plates 111 and 112 are pressing plates that prevent bulging by pressing the battery cell 1 during formation. Specifically, in the device 100 for charging and discharging a battery cell according to the present application, the first and second plates 111 and 112 are arranged at regular intervals and are configured to be movable so that the intervals can be increased or decreased. That is, the battery cell 1 is arranged between the first and second plates 111 and 112, and the first and second plates 111 and 112 are moved in the direction of pressing both surfaces of the battery cell 1, thereby pressing the battery cell 1.

[0069] Although not shown in the drawings, the first and second plates are connected in a manner allowing translational motion along an axis extending in one side, a gear is connected to one end of the axis, and a driving motor can be connected to the gear. Here, any mechanical combination can be used as long as it has a driving mechanism capable of moving the first and second plates 111 and 112 in the direction of pressing the battery cell 1.

[0070] On the other hand, the first and second plates 111 and 112 are made of a material having high rigidity so that the first and second plates 111 and 112 are not deformed due to high heat and high pressure. For example, the first and second plates 111 and 112 are made of reinforced plastic.

[0071] In addition, the first holder 121 and the second holder 122 contact the lead region la of the battery cell 1, thereby applying a current to the battery cell 1 and detecting a voltage. Here, the lead region la of the battery cell 1 refers to an electrode lead. In particular, since the first holder 121 and the second holder 122 are connected to the first plate 111 and the second plate 112, respectively, the first holder 121 and the second holder 122 are configured to be integrally moved when the first plate 111 and the second plate 112 are moved. The first holder 121 and the second holder 122 are connected to the first plate 111 and the second plate 112, respectively, and protrude at portions facing each other to contact the lead region la of the battery cell 1. Specifically, the first holder 121 is connected to each of both ends of the first plate 111 and is arranged perpendicular to the first plate 111. In addition, the second holder 122 is connected to each of both ends of the second plate 112 and is arranged perpendicular to the second plate 112.

[0072] The first holder 121 and the second holder 122 have a current terminal (not shown) for current application that contacts and is electrically connected to the lead region la of the battery cell 1, and the first holder 121 and the second holder 122 have a voltage terminal (not shown) for voltage detection that contacts and is electrically connected to the lead region la of the battery cell 1. The first holder 121 and the second holder 122 can be composed of the current terminal and the voltage terminal, but the first holder 121 and the second holder 122 can further include the current terminal and the voltage terminal as described above. In particular, the current terminal and the voltage terminal are configured to electrically contact the lead region la of the battery cell 1 when the first plate 111 and the second plate 112 press the battery cell 1. In addition, a cable (not shown) for supplying the current terminal is connected to the current terminal and the voltage terminal.

[0073] In addition, the first holder 121 and the second holder 122 have a convex or concave grid on a surface that contacts the lead region la of the battery cell 1. Specifically, by forming a grid (see FIG. 6) on the surface of the first holder 121 and the second holder 122, the fixing force of the first holder 121 and the second holder 122 on the lead region la of the battery cell 1 can be enhanced. Figure 4

[0074] ​Further, the device 100 for charging and discharging a battery cell according to the present application includes first and second pressing pads 131 and 132 located at the inner side of the first and second holders 121 and 122 to contact the platform region 1b of the battery cell 1. The first and second pressing pads 131 and 132 serve to suppress a bulging phenomenon of the platform region 1b of the battery cell 1 during a formation process of the battery cell 1, and to prevent pouch deformation in the platform region 1b of the battery cell 1. Further, elastic pressing members 140 are interposed between the first pressing pad 131 and the first plate 111 and between the second pressing pad 132 and the second plate 112. Specifically, the first pressing pad 131 is mounted on both sides of the first plate 111 by the elastic pressing members 140, respectively, and is mounted at the inner side of the first holder 121. Further, the second pressing pad 132 is mounted on both sides of the second plate 112 by the elastic pressing members 140, respectively, and is mounted at the inner side of the second holder 122. At this time, the elastic pressing members 140 can be coil springs.

[0075] Since the first and second pressing pads 131 and 132 are connected to the first and second plates 111 and 112 and the elastic pressing members 140, respectively, the first and second pressing pads 131 and 132 can be integrally moved when the first and second plates 111 and 112 are moved. That is, when the first and second plates 111 and 112 press the body region 1c of the battery cell 1, the first and second pressing pads 131 and 132 press the platform region 1b of the battery cell 1. At this time, the first and second pressing pads 131 and 132 are elastically pushed into the elastic pressing members 140, and the impact can be absorbed when contacting the platform region 1b of the battery cell 1, and the contact state can be stably maintained due to the application of the elastic restoring force of the elastic pressing members 140.

[0076] Further, the first holder 121 and the second holder 122 are protruded to have a height greater than that in a state where the first pressing pad 131 and the second pressing pad 132 are restored by the elastic pressing member 140. Further, it is shown that the first holder 121 and the second holder 122 are protruded to have a height greater than that in a state where the first pressing pad 131 and the second pressing pad 132 are restored by the elastic pressing member 140, but the present application is not limited to this example. Specifically, the first holder 121 and the second holder 122 are protruded to have a height greater than that in a state where the first pressing pad 131 and the second pressing pad 132 are restored by the elastic pressing member 140 by about 10% or more. For example, when the height in a state where the first pressing pad 131 and the second pressing pad 132 are restored by the elastic pressing member 140 is 20 mm, the height of the protruding structure of the first holder and the second holder becomes 22 mm. This is to prevent the first holder 121 and the second holder 122 from being separated from the lead region la of the battery cell 1 when the bulging phenomenon occurs in the platform region lb during the formation process of the battery cell 1.

[0077] Further, the first pressing pad 131 and the second pressing pad 132 can have a bar shape having a size corresponding to 80% or more of the width and the length of the platform region lb of the battery cell 1. For example, the width and the length of the first pressing pad 131 and the second pressing pad 132 can correspond to the width and the length of the platform region lb of the battery cell 1. This is to effectively perform the pressurization by increasing the area of the platform region lb of the battery cell 1 directly contacted by the first pressing pad 131 and the second pressing pad 132. Further, as a portion (see Figure 5 ) directly contacting the platform region lb of the battery cell 1, the first pressing pad 131 and the second pressing pad 132 can be made of an epoxy resin material.

[0078] Further, the first pressing pad 131 and the second pressing pad 132 can be integrally formed with the first holder 121 and the second holder 122, respectively, but a step is not desired to be formed in the lead region la and the platform region lb of the battery cell 1. Further, the bulging phenomenon can occur in the platform region lb. Thus, in the case where the first pressing pad 131 and the second pressing pad 132 are integrally formed with the first holder and the second holder, respectively, the first holder and the second holder can be separated from the lead region la of the battery cell 1.

[0079] With such a configuration, the device 100 for charging and discharging the battery cell according to the present application can easily fix the lead region and suppress the bulging phenomenon of the platform region lb of the battery cell 1 during the formation process of the battery cell 1.

[0080] (Second Embodiment)

[0081] Figure 6 is a schematic diagram showing an apparatus for charging and discharging a battery cell according to one embodiment of the present application.

[0082] Referring to Figure 6 , the apparatus 200 for charging and discharging a battery cell includes a first plate 211 and a second plate 212 having a battery cell therebetween and pressing two surfaces of the battery cell, a first holder 221 and a second holder 222 connected to the first plate 211 and the second plate 212, respectively, and protruding at portions facing each other to contact a lead region la of the battery cell 1, and a first pressing pad 231 and a second pressing pad 232 located at inner sides of the first holder 221 and the second holder 222 to contact a platform region lb of the battery cell 1. In particular, in the apparatus 200 for charging and discharging a battery cell according to the present application, an elastic pressing member 240 is interposed between the first pressing pad 231 and the first plate 211 and between the second pressing pad 232 and the second plate 212. In this way, the first pressing pad 231 and the second pressing pad 232 can easily press the platform region lb of the battery cell 1.

[0083] Further, in the apparatus 200 for charging and discharging a battery cell according to the present application, an elastic pressing member 240' is interposed between the first holder 221 and the first plate 211 and between the second holder 222 and the second plate 212. For example, in the apparatus 200 for charging and discharging a battery cell according to the present application, the elastic pressing member 240' is interposed between the second holder 222 and the second plate 212.

[0084] Specifically, when the first plate 211 and the second plate 212 press the battery cell 1, the second holder 222 connected to the elastic pressing member 240' is elastically pushed in, and impact when contacting the lead region la of the battery cell 1 can be absorbed, and a contact state can be stably maintained due to application of an elastic restoring force of the elastic pressing member 240'. Further, an elastic coefficient of the elastic pressing member 240' interposed between the second holder 222 and the second plate 212 can be different from an elastic coefficient of the elastic pressing member 240 interposed between the first pressing pad 231 and the second pressing pad 232 and the first plate 211 and the second plate 212.

[0085] With this configuration, the apparatus 200 for charging and discharging a battery cell according to the present application can easily fix the lead region la and suppress a bulging phenomenon of the platform region lb of the battery cell 1 during a formation process of the battery cell 1.

[0086] Since the construction of the apparatus for charging and discharging a battery cell of the present application has been described above, detailed description of each component will be omitted here.

[0087] Although the preferred example of the present application has been described with reference to the accompanying drawings, it will be understood that various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application as set forth in the appended claims.

[0088] Therefore, the technical scope of the present application should not be limited to what has been described in the above detailed description, but should be defined by the claims.

[0089] Explanation of Reference Numerals

[0090] 1: Battery cell

[0091] 1a: Lead wire region

[0092] 1b: Platform region

[0093] 1c: Body region

[0094] 10, 100, 200: Apparatus for charging and discharging a battery cell

[0095] 111, 211: First plate

[0096] 112, 212: Second plate

[0097] 121, 221: First holder

[0098] 122, 222: Second holder

[0099] 131, 231: First pressing pad

[0100] 132, 232: Second pressing pad

[0101] 140, 240, 240': Elastic pressing member

Claims

1. An apparatus for charging and discharging a battery cell, the apparatus comprising: a first plate and a second plate having a battery cell therebetween, and the first plate and the second plate pressing both surfaces of the battery cell; a first holder and a second holder connected to the first plate and the second plate, respectively, and protruding at portions facing each other to contact a tab area of the battery cell; and a first pressing pad and a second pressing pad located at inner sides of the first and second holders to contact a platform area of the battery cell, wherein an elastic pressing member is interposed between the first pressing pad and the first plate and between the second pressing pad and the second plate, and wherein the first and second pressing pads press the platform area of the battery cell. The elastic pressing member is a coil spring, a leaf spring, or rubber.

2. The apparatus of claim 1, wherein, The first and second holders protrude to have a height greater than that in a state in which the first and second pressing pads are restored by the elastic pressing member.

3. The apparatus of claim 1, wherein, The first and second holders have a relief or a grid of recesses on a surface contacting the tab area of the battery cell.

4. The apparatus of claim 1, wherein, The depth of the recesses or the height of the protrusions of the grid formed on the first and second holders is averaged in a range of 0.001 mm to 1 mm.

5. The apparatus of claim 4, wherein, An additional elastic pressing member is interposed in at least one of a space between the first holder and the first plate and a space between the second holder and the second plate.

6. The apparatus of claim 1, wherein, The first and second pressing pads have a bar shape having a size corresponding to 80% or more of a width and a length of the platform area of the battery cell.

7. The apparatus of claim 1, wherein, The first holder is connected to each of both ends of the first plate and is disposed perpendicular to the first plate, and 8. The apparatus of claim 1, wherein, wherein the second holder is connected to each of both ends of the second plate and is disposed perpendicular to the second plate. The first pressing pad is respectively mounted on both sides of the first plate by the elastic pressing member and is mounted at an inner side of the first holder, 9. The apparatus of claim 8, wherein, wherein the second pressing pad is respectively mounted on both sides of the second plate by the elastic pressing member and is mounted at an inner side of the second holder. The first and second plates are made of an insulating material, and 10. The apparatus of claim 1, wherein, wherein the first and second holders are made of an electrically conductive material. The first and second holders have a current terminal for current application that contacts and is electrically connected to the tab area of the battery cell.

11. The apparatus of claim 1, wherein, The first and second holders have a voltage terminal for voltage detection that contacts and is electrically connected to the tab area of the battery cell.

12. The apparatus of claim 1, wherein, 13.A method of charging and discharging a battery cell using the apparatus of claim 1. ​

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