Battery cell pressurization and charging / discharging system

Abstract

The present invention relates to a battery cell pressurizing and charging / discharging system including an inner frame into which a battery cell is inserted, a plate that pressurizes the battery cell, a pressurizing block that is movable on the plate in the direction in which the plate extends and grips the battery cell, and an outer frame on which an inner tab that is disposed on the outer periphery of the inner frame and electrically connected to the pressurizing block by wiring is disposed.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0113937, filed on September 8, 2022, and incorporates all of the contents disclosed in the documents of that Korean patent application as part of this specification.

[0002] The present invention relates to a battery cell pressurizing and charging / discharging system, and more particularly to a battery cell pressurizing and charging / discharging system that can pressurize, charge, and discharge a battery cell without changing an internal frame even if the size of the battery cell is changed. [Background technology]

[0003] Recently, the demand for environmentally friendly alternative energy sources has been increasing due to the rising cost of energy sources caused by the depletion of fossil fuels and the worsening of environmental pollution. Accordingly, research into various power generation technologies, such as nuclear, wind, tidal, and solar power, has been progressing, and there has also been growing interest in power storage devices to use the generated energy more efficiently.

[0004] In particular, with the technological development and increasing demand for medium- to large-scale applications such as electric vehicles and energy storage systems (ESS), the demand for batteries as an energy source is rapidly increasing, and research into batteries that can meet various requirements is ongoing.

[0005] Typically, in terms of battery shape, there is a high demand for thin prismatic secondary batteries and pouch-type secondary batteries, and in terms of materials, there is a growing demand for lithium secondary batteries such as lithium ion batteries, lithium ion polymer batteries, and lithium all-solid-state batteries, which have advantages such as high energy density, discharge voltage, and output stability.

[0006] Such secondary batteries have an electrode assembly built into a battery case, which includes a positive electrode, a negative electrode, a separator disposed between them, and an electrolyte, and the positive and negative electrode tabs are welded to two electrode tabs and sealed so that they are exposed to the outside of the battery case. These electrode tabs are electrically connected to an external device through contacts, and the secondary battery can supply power to or receive power from an external device through the electrode tabs.

[0007] Meanwhile, a secondary battery may be manufactured by activating the battery after a step of housing the electrode assembly in a battery case and injecting an electrolyte solution into the battery case, where the activation step may include a step of mounting the secondary battery on a frame of a charging / discharging device and charging / discharging the secondary battery under pressure under conditions required for activation.

[0008] In this case, if the size of the electrode assembly is changed, a frame that matches the changed size must be reused, which results in a problem of wasted time and cost in manufacturing the secondary battery. Therefore, research is being conducted to solve this problem. Summary of the Invention [Problem to be solved by the invention]

[0009] SUMMARY OF THE INVENTION An object of the present invention is to provide a battery cell pressurizing and charging / discharging system that can perform pressurizing and charging / discharging using the same frame even if the size of the electrode assembly is changed.

[0010] Another object of the present invention is to provide a battery cell pressurizing and charging / discharging system that can use a charger / discharger for capacity inspection, without using a charger / discharger dedicated to charging / discharging. [Means for solving the problem]

[0011] In order to achieve the above-described object of the present invention, a battery cell pressurizing and charge / discharge system according to one embodiment of the present invention may include an inner frame into which a battery cell is inserted, a plate that pressurizes the battery cell, a pressurizing block that is movable on the plate in an extension direction of the plate and grips the battery cell, and an outer frame that is disposed on an outer periphery of the inner frame and has an inner tab that is electrically connected to the pressurizing block by a wiring.

[0012] In one embodiment, the pressure block may include a circuit board disposed in a portion that comes into contact with the battery cell.

[0013] In one embodiment, the battery pack may further include a load cell disposed within the internal frame and capable of measuring the pressure applied to the battery cell.

[0014] In one embodiment, the apparatus further includes a pressure shaft that applies pressure to the plate, and the pressure shaft may apply pressure to the plate by rotation.

[0015] In one embodiment, the rotation may be a screw rotation.

[0016] In one embodiment, the pressure block may grip a tab of the battery cell.

[0017] In one embodiment, the battery cells may be bi-directional tab battery cells having tabs on both ends.

[0018] In one embodiment, the battery cells may be one-way tab battery cells having a tab on only one end.

[0019] In one embodiment, two or more pressure blocks may be arranged on one plate.

[0020] In one embodiment, the battery pack may further include a transfer device that transfers the external frame and a charge / discharge device into which the transferred external frame is inserted, wherein the charge / discharge device has an external tab electrically connected to the internal tab, and current applied by the charge / discharge device may be transmitted to the battery cells via the external tab, the internal tab, and the pressure block.

[0021] In one embodiment, the outer tab may be a tab gripper that grips and electrically couples with the inner tab.

[0022] In one embodiment, the wiring may be spring-like and connect the inner tab and the pressure block. [Effects of the Invention]

[0023] According to the present invention, the battery cell pressurizing and charge / discharge system can apply pressure to battery cells of various sizes without changing the internal frame, because the pressurizing block that is movable on the plate grips the tabs of the battery cells regardless of the size of the battery cells.

[0024] The spring-like wire can be stretched. This allows the internal tab to be connected to the pressure block by a wire that can be extended in length while being fixed in position within the internal frame. When the pressure block moves, the position of the internal tab does not change, and only the length of the wire can be extended or shortened. The external tab may be fixedly disposed in a position corresponding to the internal tab within the external frame.

[0025] Therefore, the battery cell pressurizing and charging / discharging system can use the same inner frame, outer frame, and charging / discharging device regardless of the size of the battery cell, thereby reducing time and costs compared to conventional pressurizing and charging / discharging systems that require replacing the frame every time the size of the battery cell changes. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a block diagram illustrating a battery cell pressurization and charging / discharging system according to an embodiment of the present invention. [Figure 2] FIG. 2 shows an embodiment of the pressure tray of FIG. 1. [Figure 3] 2 is a diagram showing a state in which the battery cells placed inside the pressure tray of FIG. 1 are pressurized. FIG. [Figure 4a] 2 is a diagram showing one embodiment of a pressure block included in the pressure tray of FIG. 1. FIG. [Figure 4b] 2 is a diagram showing one embodiment of a pressure block included in the pressure tray of FIG. 1. FIG. [Figure 4c] 2 is a diagram showing one embodiment of a pressure block included in the pressure tray of FIG. 1. FIG. [Figure 5] 1 illustrates a cell battery pressurization and charge / discharge system according to one embodiment of the present invention. [Figure 6] FIG. 1 illustrates a pressure tray according to one embodiment of the present invention. [Figure 7] FIG. 1 illustrates a pressure tray according to one embodiment of the present invention. [Figure 8a] 8 is a diagram showing one embodiment of a pressure block included in the pressure tray of FIG. 7. [Figure 8b] 8 is a diagram showing one embodiment of a pressure block included in the pressure tray of FIG. 7. [Figure 8c] 8 is a diagram showing one embodiment of a pressure block included in the pressure tray of FIG. 7. DETAILED DESCRIPTION OF THE INVENTION

[0027] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Prior to this, the terms and phrases used in this specification and claims should not be construed as being limited to their ordinary or dictionary meanings, but should be construed in a way that is consistent with the technical concept of the present invention, based on the principle that the inventor can appropriately define the concept of the term to best describe his or her invention. Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are merely some of the most preferred embodiments of the present invention and do not represent the entire technical concept of the present invention, and therefore, at the time of filing this application, there are various equivalents and modifications that can be substituted for them.

[0028] FIG. 1 is a block diagram illustrating a battery cell pressurizing and charging / discharging system according to one embodiment of the present invention.

[0029] Referring to FIG. 1 , the battery cell pressurization and charge / discharge system 1000 may include a pressurization tray 1, a transfer device 2, and a charge / discharge device 3. The pressurization tray 1 may pressurize the battery cells. To this end, the battery cells may be placed on the pressurization tray 1. The charge / discharge device 3 may charge and discharge the battery cells placed on the pressurization tray 1. The process of charging and discharging the battery cells may be defined as an activation process that activates the battery cells. During the activation process, the battery cells may expand due to changes in the thickness of the electrode plates or gas generation. In the battery cell pressurization and charge / discharge system 1000, the pressurization tray 1 may pressurize the battery cells to prevent the battery cells from expanding, while the charge / discharge device 3 charges the battery cells.

[0030] The pressure tray (1) with the battery cells loaded therein may be transferred to the charging / discharging device (3) by a transfer device (2). The transfer device (2) may be used in a variety of ways as long as it is capable of transferring the pressure tray (1) to the charging / discharging device (3). The transfer device (2) may include a conveyor belt, a crane, etc. A stacker crane may be used as the crane. For example, the battery cells may be loaded onto the pressure tray (1) at a pressure stage. The pressure tray (1) may move to the charging / discharging device (3) via a conveyor belt while pressurizing the loaded battery cells. Then, a stacker crane may load the pressure tray (1) into the charging / discharging device (3).

[0031] The pressure tray (1) may be placed in the charge / discharge device (3) by the transfer device (2) and electrically connected to the charge / discharge device (3). The charge / discharge device (3) may apply an electric current to the pressure tray (1).

[0032] FIG. 2 is a diagram showing one embodiment of the pressure tray of FIG. 1, and FIG. 3 is a diagram showing the state in which the battery cells placed inside the pressure tray of FIG. 1 are pressurized.

[0033] 2, the pressure tray 1 may include an inner frame 10, an outer frame 20, battery cells 30, plates, a pressure shaft 120, a pressure adjustment member 130, a load cell 140, a pressure block 150, inner tabs 160, and wiring 170. The plates may include a main plate 100 and a sub-plate 110.

[0034] The internal frame 10 can provide a space for accommodating the battery cells 30. The internal frame 10 can be made of a rigid material to accommodate and secure the battery cells 30. The battery cells 30 can be inserted into the internal frame 10. After being inserted into the internal frame 10, the battery cells 30 can be activated by applying pressure and charging / discharging. At least one battery cell 30 can be inserted.

[0035] The main plate 100 and the sub-plate 110 may apply pressure to the battery cells 30. To this end, the main plate 100 may have a plate-like structure. The main plate 100 may extend in a first direction (DR1). The main plate 100 may apply pressure in a second direction (DR2) perpendicular to the first direction (DR1). To this end, the main plate 100 may be made of a material that is resistant to deformation under high heat and pressure and has high mechanical rigidity. For example, the main plate 100 may be made of a metal material. Of course, the main plate 100 may also be made of other materials with excellent mechanical rigidity, such as aluminum, stainless steel, reinforced plastic, reinforced ceramic, or reinforced glass. When the main plate 100 applies pressure in the second direction (DR2), the sub-plate 110 may be subsequently pressed in the second direction (DR2).

[0036] An interleaf may be fixed between the main plate (100) and the sub-plate (110). The interleaf may be fixed to the top of the main plate (100) and the sub-plate (110) with pins and may serve to fix the battery cells before they are pressurized. The interleaf may have a length shorter than the length of the battery cells. It is preferable that the interleaf be arranged long enough to cover the body of the battery cells. If the tabs of the battery cells are covered by the interleaf, the pressure block (150) cannot be electrically connected to the tabs of the battery cells. The interleaf may be made of flame-retardant coated paper or film.

[0037] 3, a plurality of battery cells 30, a main plate 100, and a sub-plate 110 may be arranged in the internal frame 10, and the main plate 100 and the sub-plate 110 may be located adjacent to each of the plurality of battery cells 30. Each battery cell 30 may be pressurized by the adjacent main plate 100 and sub-plate 110.

[0038] The pressure shaft 120 and the pressure adjustment member 130 may apply pressure to the main plate 100. The pressure adjustment member 130 may rotate a gear to rotate the pressure shaft 120. For example, the pressure shaft 120 may apply pressure to the main plate 100 through screw rotation. The pressure applied to the main plate 100 may be transmitted to the sub-plate 110, thereby applying pressure to the multiple battery cells 30 together. The pressure shaft 120 may have a thread, and the sub-plate 110 may contact the thread via a bearing or the like. This allows the sub-plate 110 to move in the second direction (DR2) as the pressure shaft 120 rotates. Although not shown in the drawings, a mounting shaft may be added to mount the main plate 100 and the sub-plate 110.

[0039] The load cell 140 can measure the pressure applied to the battery cells 30. The load cell 140 can be disposed in the inner frame 10 in the direction in which the pressure shaft 120 applies pressure. As shown in FIG. 3, when pressure is applied by the pressure shaft 120, the load cell 140 can come into contact with the sub-plate 110, and the sub-plate 110 can also apply pressure to the load cell 140. The load cell 140 can generate a signal to stop applying pressure if a pressure exceeding a preset pressure is applied. For example, the load cell 140 can generate a signal to stop applying pressure if a pressure exceeding 3000 kgf is applied. This allows the pressure tray 1 to prevent damage to the battery cells 30 due to excessive pressure being applied to them. The load cell 140 is electrically connected and operable only during the pressure stage and does not operate during the charging and discharging processes.

[0040] The pressure block 150 may be disposed on the main plate 100 and the sub-plate 110. The pressure block 150 may move on the main plate 100 and the sub-plate 110 in the direction in which the main plate 100 and the sub-plate 110 extend. That is, the pressure block 150 may move in the first direction DR1. This allows the pressure block 150 to move alone to grip a battery cell 30 of a different length, without the need to modify the inner frame 10. The pressure block 150 may be electrically connected to the wiring 170.

[0041] Two or more pressure blocks 150 may be present on the main plate 100 and the sub-plate 110. The pressure blocks 150 may contact the tabs of the battery cells 30. The battery cells 30 shown in FIGS. 2 and 3 may be defined as bidirectional tab battery cells with tabs at both ends. The pressure blocks 150 may contact the tabs at both ends of the battery cells 30. In this case, the pressure blocks 150 may include a circuit board disposed in a portion that contacts the battery cells 30. The circuit board may be a printed circuit board. The pressure blocks 150 may be electrically connected to the battery cells 30 via the circuit board.

[0042] The internal tab 160 may be disposed inside the outer frame 20. The internal tab 160 may be connected to the pressure block 150 by a wire 170. Thus, a signal transmitted from the outside to the internal tab 160 may be transmitted to the pressure block 150 via the wire 170. The wire 170 may be arranged in a spring-like manner to facilitate length adjustment. Therefore, the wire 170 may not break even when the main plate 100 and the sub-plate 110 move in the second direction DR2. If the length of the wire 170 is fixed, the connection between the pressure block 150 and the wire 170 may be broken as the main plate 100 and the sub-plate 110 move. The signal transmitted to the main plate 100 may then be transmitted to the battery cell 30 through the pressure block 150. That is, the inner tab (160), the wiring (170), the pressure block (150), and the battery cell (30) may be electrically connected.

[0043] 4a to 4c are diagrams showing an embodiment of a pressure block included in the pressure tray of FIG.

[0044] FIG. 4a is a view showing the subplate (110) as viewed from the second direction (DR2), and FIG. 4b is a view showing the subplate (110) as viewed from the opposite direction to the second direction (DR2). Referring to FIG. 4a, holes (H) may be formed at both ends of the subplate (110). The pressure shaft (120) described above may be disposed so as to pass through the holes (H). A pressure block (150) may be disposed on the subplate (110). The pressure block (150) may move on the subplate (110) in the first direction (DR1) and in the direction opposite to the first direction (DR1). This allows the pressure block (150) to move and come into contact with the tabs of the battery cells even if the length of the battery cells in the first direction (DR1) changes.

[0045] 4c is a side view of the subplate (110). The pressure block (150) may include a first subpressure block (151), a second subpressure block (152), and a connecting member (153). The first subpressure block (151) and the second subpressure block (152) may be connected by the connecting member (153). In this manner, the pressure block (150) may be disposed on the subplate (110) with multiple members connected, and may move in a first direction (DR1) and a direction opposite to the first direction (DR1).

[0046] The first sub-pressing block 151 may include a spring, so that the first sub-pressing block 151 may be compressed when pressing the tabs of the battery cells. A circuit board may be disposed on the second sub-pressing block 152. In this case, the second sub-pressing block 152 may be connected to the wiring 170 described in FIGS. 2 and 3. Thus, the pressing block 150 may be electrically connected to the tabs of the battery cells via the second sub-pressing block 152. However, this is merely an example, and the circuit board may be disposed on the first sub-pressing block 151, and the second sub-pressing block 152 may include a spring.

[0047] 4a to 4c have been described with reference to the sub-plate (110), but the contents of FIGS. 4a to 4c are also applicable to the main plate (100).

[0048] FIG. 5 is a diagram illustrating a cell battery pressurization and charge / discharge system according to one embodiment of the present invention.

[0049] Referring to FIGS. 1 and 5, the pressurized tray (1) inserted into the charging / discharging device (3) by the transfer device (2) may be electrically connected to the charging / discharging device (3).

[0050] The charging / discharging device 3 may include an external tab 180 disposed therein, which may have the form of a gripper. Accordingly, the external tab 180 may be defined as a tab gripper. The external tab 180 may grip the internal tab 160, thereby contacting and electrically connecting the internal tab 160. Alternatively, the external tab 180 and the internal tab 160 may contain a conductive material therein and be electrically connected by contacting each other. Furthermore, the external tab 180 and the internal tab 160 may each include a circuit board at an end thereof and be electrically connected by contacting each end thereof. In this manner, the charging / discharging device 3 may provide current to the internal tab 160 via the external tab 180. The current is transmitted to the battery cell 30 and serves to charge and discharge the battery cell 30.

[0051] The wire 170, which is arranged in a spring-like manner, can be stretched. As a result, the internal tab 160 can be connected to the pressure block 150 by the wire 170 while its position is fixed within the internal frame 10. When the main plate 100 and the sub-plate 110 move in the second direction DR2, the position of the internal tab 160 does not change, and only the length of the wire 170 can expand or contract. The external tab may be fixedly arranged at a position corresponding to the internal tab 160 within the external frame 20. In other words, the positions of the internal tab 160 and the external tab 180 are fixed.

[0052] Furthermore, even if the length of the battery cell 30 in the first direction (DR1) is changed, the pressing block 150 can move in the first direction (DR1) on the main plate 100 and the sub-plate 110 to grip the tabs of the battery cell 30, eliminating the need to replace the inner frame 10. Therefore, the battery cell pressing and charging / discharging system 1000 according to one embodiment may use the same inner frame 10, outer frame 20, and charging / discharging device 3 regardless of the size of the battery cell 30. This allows the battery cell pressing and charging / discharging system 1000 according to one embodiment to reduce time and cost compared to conventional pressing and charging / discharging systems that require frame replacement every time the size of the battery cell 30 is changed.

[0053] Fig. 6 is a diagram showing a pressure tray according to one embodiment of the present invention. Fig. 6 may be substantially the same as Fig. 1, except that the length of the battery cells 30 in the first direction (DR1) is shortened. Therefore, a description of the overlapping configuration will be omitted.

[0054] 1 and 6, when the length of the battery cell 30 is changed, the pressure block 150 may move on the main plate 100 and the sub-plate 110 to match the length of the battery cell 30. After moving, the pressure block 150 may grip the tab of the battery cell 30. The pressure block 150 may be electrically connected to the battery cell 30 by gripping the tab of the battery cell 30. A circuit board may be disposed where the pressure block 150 grips the tab of the battery cell 30. The circuit board may be a printed circuit board.

[0055] Fig. 7 is a diagram showing a pressure tray according to one embodiment of the present invention. Fig. 7 may be substantially the same as Fig. 1, except that the battery cells (30) are changed to one-way tab battery cells. Therefore, a description of the overlapping components will be omitted.

[0056] 1 and 7, the battery cells 30 may be unidirectional tab battery cells instead of bidirectional tab battery cells. A unidirectional tab battery cell may be defined as a battery cell having a tab on only one side of the battery cell. In this case, the battery cells 30 may have a tab on only one end. The movable pressure blocks 150 on the main plate 100 may contact different battery cells 30.

[0057] For example, the pressure block 150 located at the end of one sub-plate 110 in the first direction (DR1) may contact the battery cells 30 located in the first direction (DR1) among the battery cells 30 located adjacent to the sub-plate 110, and the pressure block 150 located in the opposite direction to the first direction (DR1) may contact the battery cells 30 located in the opposite direction to the first direction (DR1) among the battery cells 30 located adjacent to the sub-plate 110. In this case, since a one-way tab battery cell may have two tabs located on only one side, the structure of the pressure block 150 may be slightly different from that described above. This will be described with reference to Figures 8a to 8c.

[0058] Figures 8a to 8c are diagrams showing an embodiment of the pressure block included in the pressure tray of Figure 7. Figures 8a to 8c may be substantially the same as Figures 4a to 4c, except that an insulating member (155) is added. Therefore, a description of the overlapping configuration will be omitted.

[0059] 8a to 8c, the insulating member 155 may be disposed between the first sub-pressing block 151 and the second sub-pressing block 152. The insulating member 155 may be disposed only on either the first sub-pressing block 151 or the second sub-pressing block 152. For example, if a circuit board is disposed on the first sub-pressing block 151, the insulating member 155 may be disposed only on the first sub-pressing block 151 side. Conversely, if a circuit board is disposed on the second sub-pressing block 152, the insulating member 155 may be disposed only on the second sub-pressing block 152 side.

[0060] The insulating member 155 can serve to insulate the circuit boards arranged on the upper and lower parts of the sub-pressing block on which the circuit board is arranged, so that the upper part of the sub-pressing block on which the circuit board is arranged can contact one of the two tabs of the battery cell, and the lower part can contact the other of the two tabs of the battery cell.

[0061] At this time, the wires 170 shown in FIG. 7 may be plural and connected to the upper and lower parts of the sub-pressurizing block, respectively.

[0062] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention. [Explanation of symbols]

[0063] 1: Pressure tray 2: Transfer device 3: Charge / discharge device 10: Internal frame 20: External frame 30: Battery cell 100: Main plate 110: Subplate 120: Pressure shaft 130: Pressure adjustment member 140: Load cell 150: Pressure block 160: Internal tab 170: Wiring 180: External tap 151: First sub-pressure block 152: Second sub-pressure block 153: Connecting member 155: Insulating material

Claims

1. an internal frame into which the battery cells are inserted; a plate that applies pressure to the battery cell; a pressure block that is movable on the plate in the direction in which the plate extends and that grips the battery cell; an outer frame having an inner tab disposed on an outer periphery of the inner frame, the inner tab being electrically connected to the pressing block by a wiring;

2. The battery cell pressurizing and charging / discharging system according to claim 1 , wherein the pressurizing block includes a circuit board disposed in a portion that contacts the battery cell.

3. 2. The battery cell pressurizing and charging / discharging system according to claim 1, further comprising a load cell disposed in the internal frame and capable of measuring a pressure applied to the battery cell.

4. Further comprising a pressure shaft that applies pressure to the plate; The battery cell pressurizing and charging / discharging system according to claim 1 , wherein the pressurizing shaft pressurizes the plate by rotation.

5. The battery cell pressurizing and charging / discharging system according to claim 4 , wherein the rotation is a screw rotation.

6. The battery cell pressurizing and charging / discharging system according to claim 1 , wherein the pressing block grips a tab of the battery cell.

7. 7. The battery cell pressurizing and charging / discharging system according to claim 6, wherein the battery cell is a bidirectional tab battery cell having tabs at both ends.

8. 7. The battery cell pressurizing and charging / discharging system according to claim 6, wherein the battery cell is a one-way tab battery cell having a tab only at one end.

9. The battery cell pressurizing and charging / discharging system according to claim 6 , wherein two or more pressurizing blocks are arranged on one plate.

10. a transport device for transporting the outer frame; and The method further includes a charging / discharging device into which the transported outer frame is inserted, The charging / discharging device has an outer tab electrically connected to the inner tab, 2. The battery cell pressurizing and charging / discharging system according to claim 1, wherein the current applied from the charging / discharging device is transmitted to the battery cell via the outer tab, the inner tab, and the pressing block.

11. 2. The battery cell pressurizing and charging / discharging system according to claim 1, wherein the outer tab is a tab gripper that grips and electrically connects the inner tab.

12. The battery cell pressurizing and charging / discharging system according to claim 1 , wherein the wiring is spring-shaped and connects the inner tab and the pressing block.

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