Method for laminating battery cells

Abstract

The present invention relates to a method for laminating a battery cell, comprising: a step for establishing a virtual baseline at the center of the battery cell and laminating a plurality of battery cells in which the baselines are arranged; and a feature in which the stacked battery cells are aligned and stacked such that baselines coincide, in which positions of end portions of both corner portions of the battery cells are identified using a visual sensor, and virtual baselines passing through centers of the battery cells are configured based on the identified positions of the end portions.

Description

Technical Field

[0001] The present invention relates to a method for stacking battery cells, which is characterized by establishing an imaginary baseline in each battery cell and aligning the battery cells so that the baselines coincide.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0005584, filed on January 13, 2023, the entire contents of which are incorporated herein by reference. Background Art

[0003] Secondary batteries, which have electrical characteristics such as high energy density and are easily applicable according to the product range, are widely used not only in portable devices but also in electric vehicles or hybrid vehicles driven by electric energy, energy storage systems, etc. These secondary batteries have attracted attention as new energy sources for environmental protection and improved energy efficiency, not only because they have the main advantage of significantly reducing the use of fossil fuels, but also because they do not generate any by-products when using energy.

[0004] Although small mobile devices use one or two battery cells per device, medium and large devices such as cars require high power and large capacity. Therefore, medium to large battery modules that electrically connect many battery cells are used.

[0005] Since the middle to large battery modules are expected to be manufactured with the smallest possible size and weight, square batteries, pouch type batteries, etc., which can be stacked with high density and have a small weight relative to capacity, are mainly used as battery cells in the middle to large battery modules.

[0006] Generally, a battery module may include a frame member having an open front side and an open rear side to accommodate a battery cell stack in an internal space to protect the battery cell stack from external impact, heat, or vibration.

[0007] Meanwhile, in a battery cell stack in the form of a plurality of battery cells stacked together, alignment of the respective battery cells is an important issue affecting the performance of the secondary battery.

[0008] Before stacking the battery cells C, Figure 1 As shown, the positions of the respective battery cells C are corrected and then the battery cells C are stacked, but partial positional imbalance may occur depending on structural limitations of the battery cells C and the like.

[0009] Figure 2 A battery cell stack Cs included in a battery module is shown, and it can be seen that there is misalignment between the battery cells Cs, in which the position of the positive electrode lead L1 and the position of the negative electrode lead L2 are opposite to each other.

[0010] In this manner, if the positions of the respective battery cells C included in the battery cell stack Cs are slightly misaligned, a contact error may occur between the electrode lead Le and the bus bar B electrically connected to the electrode lead Le.

[0011] [Prior art literature]

[0012] [Patent Document]

[0013] Korean Patent Publication No. 10-2021-0049471 Summary of the invention

[0014] Technical issues

[0015] Therefore, the present invention is intended to solve the above-mentioned problems and to provide a method of stacking battery cells capable of improving the alignment of individual battery cells with respect to stacked battery cells.

[0016] Other objects and advantages of the present invention will be understood from the following description, will become more apparent from the embodiments of the present invention, and will be easily understood that the objects and advantages of the present invention can be achieved by the methods and combinations disclosed in the claims of this patent.

[0017] Technical Solution

[0018] The present invention provides a battery cell stacking method, which comprises: establishing an imaginary baseline at the center of the battery cell; and stacking a plurality of battery cells with the established baseline, wherein the plurality of battery cells are stacked by being aligned in such a way that the baselines overlap.

[0019] The battery cell may include an electrode assembly in which a plurality of electrodes are stacked, and electrode leads electrically connected to the electrode assembly are led out from both sides of the battery cell, respectively.

[0020] The baseline may be established at a position corresponding to the center of an electrode included in an uppermost portion of the electrode assembly.

[0021] The battery cell may include: a receiving portion in which the electrode assembly is located; and a lead-out portion in which the electrode lead is located.

[0022] A step is formed between the receiving portion and the lead-out portion, and the center of the battery cell may correspond to a position that is centered with positions where the steps start on both sides of the receiving portion as base points.

[0023] The center of the battery cell may correspond to a position centered around corners at both ends of the receiving portion.

[0024] The center of the battery cell may correspond to a position that is halfway between the positions of the corners of both ends of the receiving portion.

[0025] The base line may be formed to pass through the center of the battery cell so that the electrode leads are located on both sides.

[0026] The base line may be formed at a position centered on positions of both ends of electrodes included in an uppermost portion of the electrode assembly.

[0027] The electrode assembly includes a positive electrode, a separator and a negative electrode, wherein the electrode lead includes: a positive electrode lead, which is electrically connected to the positive electrode of the electrode assembly; and a negative electrode lead, which is electrically connected to the negative electrode of the electrode assembly, and wherein an adjacent pair of battery cells are alternately stacked so that the position of the positive electrode lead is opposite to that of the negative electrode lead.

[0028] The positions of the battery cells can be adjusted by moving them along the length direction of the battery cells in such a way that the base lines coincide with each other.

[0029] Beneficial Effects

[0030] According to the present invention, for stacking battery cells, alignment of the respective battery cells can be improved, thereby improving the stability of the secondary battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A conventional battery cell stack formation process is shown.

[0032] Figure 2 is a diagram of a battery cell stack including a conventional battery module.

[0033] Figure 3 This is a flow chart of a method for stacking battery cells of the present invention.

[0034] Figure 4 A battery cell and a visual sensor used in a battery cell stacking method according to a first embodiment of the present invention are shown.

[0035] Figure 5 yes Figure 4 Side view of the battery cell and vision sensor.

[0036] Figure 6 The boundary points between the receiving portion and the discharge portion of the battery cell are shown.

[0037] Figure 7 This is a diagram showing a stacking process of a plurality of battery cells.

[0038] Figure 8 A battery cell and a visual sensor used in a battery cell stacking method according to a second embodiment of the present invention are shown.

[0039] Fig. 9 yes Figure 8 Side view of the battery cell and vision sensor. DETAILED DESCRIPTION

[0040] The present invention will now be described in detail with reference to the accompanying drawings, which show preferred embodiments of the present invention. It should therefore be understood that the terms and words used in this specification and claims should not be interpreted in their ordinary or dictionary meanings, but should be interpreted in meanings and concepts consistent with the technical concept of the present invention based on the principle that the inventor can define the terminology he or she deems appropriate to best describe the present invention.

[0041] However, it will be understood that the present invention is not limited to the specific embodiments, and includes all modifications, equivalents, or replacements within the spirit and technical scope of the present invention.

[0042] Furthermore, in describing the present invention, in the case where a detailed description of a configuration or function of the related disclosure is considered to obscure the subject matter of the present invention, such a detailed description is omitted.

[0043] The present invention is shown in the embodiments to more completely explain the present invention to those skilled in the art, and therefore, for the sake of clarity, the shapes and sizes of the components in the drawings may be magnified, omitted or schematically shown. Therefore, the size or ratio of each component does not necessarily represent its actual size or ratio.

[0044] The present invention relates to a method for stacking battery cells, which is characterized by establishing an imaginary baseline in each battery cell and aligning and stacking the battery cells so that the baselines coincide.

[0045] A plurality of battery cells are stacked in a certain number to form a battery cell stack, and the battery cell stack thus formed is combined with bus bars electrically connected to the respective battery cells and a frame closing an outer surface to protect the battery cell stack to form a battery module.

[0046] Figure 3 Hereinafter, the stacking method of the battery cells of the present invention will be described with reference to the above flowchart.

[0047] (First embodiment)

[0048] S1: Establishing baseline BL

[0049] An imaginary base line BL is established at the center of the battery cell C.

[0050] The center of the battery cell C can be found by recognizing the corners Co on both sides of the battery cell C with the vision sensor S.

[0051] Figure 4 The battery cell C used in the stacking method of the battery cell C according to the first embodiment of the present invention and the visual sensor S for locating the center of the battery cell C are shown, and Figure 5 yes Figure 4 Side view of the battery cell C and visual sensor S.

[0052] The battery cell C has an electrode assembly (not shown) in which a plurality of electrodes are stacked and accommodated, and Figure 4 and Figure 5 The electrode leads Le are shown to be electrically connected to the electrode assembly on both sides.

[0053] The electrode assembly includes a positive electrode, a separator, and a negative electrode, wherein the positive electrode, the separator, and the negative electrode are alternately stacked.

[0054] The electrode leads Le include a positive electrode lead L1 electrically connected to the positive electrode of the electrode assembly and a negative electrode lead L2 electrically connected to the negative electrode of the electrode assembly.

[0055] Adjacent pairs of battery cells C may be alternately stacked such that the positions of the positive electrode lead L1 and the negative electrode lead L2 are reversed, or may be stacked in pairs such that the positive electrode lead L1 and the negative electrode lead L2 are in the same position.

[0056] like Figure 5 As shown, the battery cell C includes a receiving portion Pr and a lead-out portion Pe.

[0057] The electrode assembly may be located in the receiving portion Pr, and the electrode lead Le may be located in the lead-out portion Pe.

[0058] A step may be formed between the receiving portion Pr and the lead-out portion Pe. In this case, the height of the step may vary according to the thickness of the electrode assembly including the receiving portion Pr.

[0059] The method of stacking battery cells C of the present invention is characterized in that imaginary base lines BL are established on the respective battery cells C to be stacked so that the base lines BL coincide with each other when the battery cells C are stacked.

[0060] The base line BL corresponds to the center of the battery cell C, and the center of each battery cell C is found based on the positions of both ends of the receiving portion Pr of the corresponding battery cell C.

[0061] In other words, the center of each battery cell C is found based on the position of half of both ends of the accommodation portion Pr.

[0062] The center of the battery cell C corresponds to the center of the electrode assembly, and the base line BL is formed to pass through the center of the battery cell C. More specifically, the base line BL is formed to pass through the center of the battery cell C so that the electrode leads Le of the battery cell C are located on both sides.

[0063] The base line BL is established at a position corresponding to the center of the electrode included in the upper portion of the electrode assembly included in the receiving portion Pr. In other words, the base line BL is formed at a position of the center of both ends of the electrode included in the uppermost portion of the electrode assembly.

[0064] Both ends of the electrode included in the uppermost portion of the electrode assembly correspond to boundary points of the receiving portion Pr and the lead-out portion Pe, or to positions where steps start on both sides of the receiving portion Pr.

[0065] Figure 6 The boundary point between the receiving portion Pr and the lead-out portion Pe of the battery cell C is shown.

[0066] like Figure 6 As shown, the step starts at the boundary point between the receiving portion Pr and the lead-out portion Pe or at both ends of the uppermost electrode included in the electrode assembly, corresponding to the end of the uppermost electrode.

[0067] like Figure 6 As shown, multiple stacked electrodes may have slightly different end positions. The present invention identifies the two ends of the electrode located at the uppermost portion of the electrode assembly to quickly locate the center of the battery cell C and establish a baseline BL, and forms an imaginary baseline BL by finding the center of the electrode based on the positions of the identified two ends of the electrode.

[0068] like Figure 4 and Figure 5 As shown, the corners at both ends of the receiving portion Pr can be recognized by the visual sensor S.

[0069] The visual sensor S is located above both sides of the battery cell C to identify the end position of the battery cell C as a target, and establishes an imaginary baseline BL passing through the center of the battery cell C based on the identified end position. In this case, the center of the battery cell C corresponds to the center position based on the corner positions of both ends of the receiving portion Pr.

[0070] In this way, each battery cell C establishes its own baseline BL.

[0071] S2: stacked battery cells C

[0072] A plurality of battery cells C are stacked to establish a base line BL.

[0073] Figure 7 The step of stacking a plurality of battery cells C is shown.

[0074] As described above, the respective battery cells C to be stacked are characterized in that the base lines BL are aligned so that the battery cells C coincide with each other.

[0075] like Figure 7As shown, before stacking the battery cells C, there may be large differences in the positions of the battery cells C. Position correction is performed on each battery cell C so that the baselines BL established in each battery cell C coincide with each other. At this time, the positions of the battery cells C are adjusted by moving them in the length direction so that the baselines BL coincide with each other.

[0076] When the base lines BL established for the plurality of battery cells C all coincide due to the position correction as described above, the battery cells C are stacked to form a single battery cell stack Cs.

[0077] (Second embodiment)

[0078] The method for stacking battery cells C of the present invention is applicable not only to battery cells C of a type in which electrode leads Le are led out at both ends, but also to battery cells C of a type in which a pair of electrode leads Le are led out at one side.

[0079] Figure 8 The battery cells C used in the stacking method of the battery cells C according to the second embodiment of the present invention and the vision sensor S for locating the position of the center of the battery cells C are shown. Fig. 9 Shown from the side view Figure 8 Battery cell C and visual sensor S.

[0080] As mentioned above Figure 8 and Fig. 9 As shown, the battery cell C has an electrode assembly (not shown) in which a plurality of electrodes are stacked and accommodated, and electrode leads Le electrically connected to the electrode assembly at one side, respectively.

[0081] The method for stacking battery cells C of the second embodiment is also characterized in that, in the same manner as the method for stacking battery cells C of the first embodiment described above, an imaginary baseline BL is established for each battery cell C to be stacked, and when stacking the battery cells C, the baseline BL is aligned so that the battery cells C coincide with each other.

[0082] The base line BL corresponds to the center of the battery cell C, and the center of each battery cell C is found based on the positions of both ends of the receiving portion Pr of the battery cell C.

[0083] In other words, the center of each battery cell C is found based on the position of half of both ends of the accommodation portion Pr.

[0084] The center of the battery cell C corresponds to the center of the electrode assembly, and the base line BL is formed to pass through the center of the battery cell C. More specifically, the base line BL is formed to pass through the center of the battery cell C so that the electrode lead Le of the battery cell C is located at one side.

[0085] The base line BL is established at a position corresponding to the center of the electrode included in the uppermost portion of the electrode assembly included in the receiving portion Pr. In other words, the base line BL is formed at a position of the center of both ends of the electrode included in the uppermost portion of the electrode assembly.

[0086] Both ends of the electrode included in the uppermost portion of the electrode assembly correspond to positions where the steps start on both sides of the receiving portion Pr.

[0087] The present invention identifies the two ends of the uppermost electrode of the electrode assembly to quickly locate the center of the battery cell C and establish the baseline BL, and forms an imaginary baseline BL by finding the center of the electrode based on the positions of the identified two ends of the electrode.

[0088] like Figure 8 and Fig. 9 As shown, the corners at both ends of the receiving portion Pr can be recognized by the visual sensor S.

[0089] The visual sensor S is located at the upper part of both sides of the battery cell C to identify the end position of the battery cell C as a target, and establishes an imaginary baseline BL passing through the center of the battery cell C based on the identified end position. In this case, the center of the battery cell C corresponds to a position halfway based on the corner positions of both ends of the receiving portion Pr.

[0090] In this way, each battery cell C establishes its own baseline BL.

[0091] As described above, the present invention has been described in more detail by the drawings and embodiments. However, since the configuration described in the drawings or embodiments described herein is only one embodiment of the present invention and does not represent the entire technical spirit of the present invention, it should be understood that when submitting this application, the present invention covers various equivalents, modifications and substitutes.

[0092] Description of Reference Numerals

[0093] Cs: battery cell stack

[0094] C: (battery) battery cell

[0095] Co: Corner

[0096] Le: Electrode lead

[0097] L1: positive lead

[0098] L2: Negative lead

[0099] B: Busbar

[0100] S: Vision sensor

[0101] BL: Baseline

[0102] Pr: Accommodation

[0103] Pe: Export department

Claims

1. A method for stacking battery cells, comprising: Establish an imaginary baseline at the center of the battery cell; as well as stacking a plurality of battery cells having the baseline; The plurality of battery cells are stacked in an aligned manner so that the base lines overlap.

2. The method for stacking battery cells according to claim 1, wherein: The battery cell includes an electrode assembly in which a plurality of electrodes are stacked, and electrode leads electrically connected to the electrode assembly are led out from both sides of the battery cell.

3. The method for stacking battery cells according to claim 2, wherein: A baseline is established at a position corresponding to a center of an electrode included in an uppermost portion of the electrode assembly.

4. The method for stacking battery cells according to claim 2, wherein: The battery cell includes: a receiving portion in which the electrode assembly is located; and a leading portion in which the electrode lead is located.

5. The method for stacking battery cells according to claim 4, wherein: A step is formed between the receiving portion and the lead-out portion, and The center of the battery cell corresponds to a position that is centered with respect to positions where the steps start on both sides of the receiving portion.

6. The method for stacking battery cells according to claim 4, wherein: The center of the battery cell corresponds to a position centered on corners at both ends of the accommodation portion.

7. The method for stacking battery cells according to claim 4, wherein: The center of the battery cell corresponds to a position halfway between the positions of the corners at both ends of the accommodation portion.

8. The method for stacking battery cells according to claim 2, wherein: The base line is formed to pass through the center of the battery cell so that the electrode leads are located on both sides.

9. The method for stacking battery cells according to claim 2, wherein: The base line is formed at a position centered on positions of both ends of the electrode included in the uppermost portion of the electrode assembly.

10. The method for stacking battery cells according to claim 2, wherein: The electrode assembly includes a positive electrode, a separator and a negative electrode, The electrode lead includes: a positive electrode lead, the positive electrode lead is electrically connected to the positive electrode of the electrode assembly; and a negative electrode lead, the negative electrode lead is electrically connected to the negative electrode of the electrode assembly, and A pair of adjacent battery cells are alternately stacked such that the position of the positive electrode lead is opposite to the position of the negative electrode lead.

11. The method for stacking battery cells according to claim 1, wherein: The positions of the battery cells are adjusted by moving along the length direction of the battery cells so that the base lines overlap.

Images