Battery cell manufacturing method and system

Abstract

The present application provides a method and system for manufacturing a battery cell, the method comprising: bonding n pairs of first and second pole pieces to the upper and lower surfaces of a diaphragm in n lamination areas, respectively, to form n lamination units; winding the diaphragm from the first lamination unit to the nth lamination unit, so that each lamination unit is bonded to the surface of the diaphragm to form a wound battery cell; wherein the length of the diaphragm between an odd-numbered lamination area and the next lamination area is equal to the sum of the lengths of the two lamination areas and the length of the diaphragm used for winding, and the length of the diaphragm between an even-numbered lamination area and the next lamination area is equal to the length of the diaphragm used for winding; the length of the diaphragm used for winding is adapted to the thickness and number of pole pieces required for winding, as well as the thickness and number of diaphragm layers. The wound battery cell has structural / safety advantages: multi-layer wrapping, overall tightness, each layer constrained by the diaphragm and unable to move, so it is not easy to be misplaced, and has high safety.

Description

Technical Field

[0001] The present application relates to the field of lithium-ion battery manufacturing, and in particular to a method and system for manufacturing lithium-ion battery cells. Background Art

[0002] The existing methods for making lithium battery cores mainly include winding and lamination. Both methods have their own advantages, but both methods also have some problems.

[0003] For example, the advantages of wound cells include high efficiency, low manufacturing costs, good overall electrode alignment, and mature process equipment. However, disadvantages are also significant, such as the risk of core deformation during later charge and discharge, and inferior product performance compared to stacked cells: high internal resistance, low rate capability, low discharge plateau, short lifespan, low energy density, limited thickness compatibility, single shape, and a narrow range of applications.

[0004] The advantages of laminated cells include high space utilization within the shell, good contact between the electrodes, resistance to deformation, and significant electrical performance compared to winding (as mentioned above). However, they suffer from low production efficiency, the risk of misalignment during operation, complex production line control relative to winding, and high investment. Although there are currently multi-station laminations, such as four-station laminations, the lamination speed can reach 0.85s / sheet, but it still does not meet the winding efficiency (the current efficiency needs to be doubled). Adjusting the speed is currently not feasible because it is too fast, the linkage device cannot reach it, and the lamination accuracy cannot be achieved. Summary of the Invention

[0005] The technical problem to be solved by the present application is that the battery cells manufactured by the existing winding method are easily deformed and have poor battery performance, and the battery cells manufactured by the stacking method have low production efficiency and the pole pieces are easily misplaced.

[0006] To solve the above technical problems, the present application discloses a method for manufacturing a battery cell, comprising:

[0007] A diaphragm is provided, wherein n lamination regions are sequentially provided from a starting position of the diaphragm, and glue is applied to the upper and lower surfaces of the diaphragms of the lamination regions for bonding the pole pieces, wherein the length of the diaphragm between an odd-numbered lamination region and the next lamination region is equal to the sum of the lengths of the two lamination regions and the length of the diaphragm for winding, and the length of the diaphragm between an even-numbered lamination region and the next lamination region is equal to the length of the diaphragm for winding;

[0008] Adhere n pairs of first and second pole pieces to the upper and lower surfaces of the diaphragm in the n lamination areas, respectively, to form n lamination units; wherein the odd-numbered lamination units are, from top to bottom, the first pole piece, the diaphragm, and the second pole piece, and the even-numbered lamination units are, from top to bottom, the second pole piece, the diaphragm, and the first pole piece;

[0009] Glue is sprayed on the upper and lower surfaces of the diaphragm between the laminated areas, and the diaphragm is wound from the first laminated unit to the nth laminated unit so that each laminated unit is adhered to the surface of the diaphragm to form a stacked battery cell; the length of the diaphragm used for winding is adapted to the thickness and number of the pole pieces required for winding and the thickness and number of layers of the diaphragm.

[0010] Optionally, the first electrode sheet is a positive electrode sheet, the second electrode sheet is a negative electrode sheet, the width of the negative electrode sheet is greater than the width of the positive electrode sheet; and the winding direction is clockwise.

[0011] Optionally, the glue comprises acetonitrile and polyethylene oxide.

[0012] The optional mass ratio of the glue is: polyethylene oxide / (acetonitrile+polyethylene oxide) is 6% to 15%, and the viscosity of the glue is 100 mPa.s to 150 mPa.s.

[0013] Optionally, the winding is performed using a flat winding needle.

[0014] To solve the above technical problems, the present application also discloses a battery cell manufacturing system, which is suitable for the above battery cell manufacturing method, including: a glue spraying device for spraying glue on the upper and lower surfaces of the diaphragm; a stacking device, arranged in the stacking area, for bonding the electrode to the diaphragm.

[0015] Optionally, the glue spraying device includes a glue storage tank and a glue spraying nozzle installed on the glue storage tank.

[0016] Optionally, the stacking device includes: a pole piece material box, a pole piece positioning mechanism and a pole piece feeding mechanism, the pole piece positioning mechanism is used to position the pole piece fed out of the pole piece material box and transfer it to the pole piece feeding mechanism, the pole piece feeding mechanism is used to adsorb the pole piece and bond the pole piece to the diaphragm surface of the stacking area.

[0017] Optionally, the battery cell manufacturing system further includes: diaphragm fixing rollers arranged above and below the diaphragm on both sides of the lamination area.

[0018] Optionally, the lamination devices of the n lamination areas perform lamination simultaneously; the glue spraying device sprays glue on the upper and lower surfaces of the diaphragm in the lamination area in sequence when the diaphragm is unwound, and sprays glue on the upper and lower surfaces of the diaphragm between the lamination areas when the diaphragm is wound.

[0019] Compared with the existing technology, the technical solution of this application has at least the following beneficial effects:

[0020] The stacking is completed by first bonding the electrodes together using a double-sided adhesive-coated separator, then by winding the separator to bond the stacking together. Appropriate spacing is provided between the stacked areas of the separator to facilitate winding. This combines stacking and winding to create a wound cell. This solves the problems of wound battery cells, such as high internal resistance, high internal stress, insufficient space utilization, low battery rate, low discharge platform, low lifespan, low energy density, narrow thickness, single shape, and limited application range. It also addresses the low production efficiency and easy misalignment of conventional stacked cells, achieving the same efficiency as winding and reducing manufacturing costs.

[0021] The stacked battery cell has structural / safety advantages: multi-layer wrapping, overall tightening, each layer is constrained by the diaphragm and cannot move, so it is not easy to dislocate and safety is guaranteed.

[0022] The glue prepared with acetonitrile and polyethylene oxide will not affect the battery performance. It usually has excellent properties such as a wide electrochemical window, high anode stability, low viscosity and high boiling point. It is beneficial to the film formation effect of the solid electrolyte interface film and can also improve battery safety.

[0023] The glue spraying device includes a glue storage tank and a glue spray nozzle; the lamination device includes feeding, electrode positioning and lamination, and simultaneously bonds the electrode and diaphragm together. Both the glue spraying device and the lamination device are easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0025] Figure 1 Schematic diagram of the lamination and winding process of the battery cell manufacturing method according to an embodiment of the present application;

[0026] Figure 2 for Figure 1 An enlarged schematic diagram of the lamination and winding process of the lamination areas A1 to A3 is shown;

[0027] Figure 3 for Figure 1 An enlarged schematic diagram of the lamination and winding process of the lamination areas A4 to A7 is shown;

[0028] Figure 4 This is a schematic structural diagram of a glue spraying device according to an embodiment of the present application;

[0029] Figure 5 Schematic diagram of the structure of the lamination device according to an embodiment of the present application. DETAILED DESCRIPTION

[0030] The following will be combined with the accompanying drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative work are within the scope of protection of this application.

[0031] In the description of the present application, it should be understood that the terms "upper", "lower", "top", "bottom", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of such features. Moreover, the terms "first", "second", etc. are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0032] The battery cell manufacturing process of this application has been improved in terms of both process flow and equipment, mainly achieving efficiency and structural advantages through the stacking method, which not only gives full play to the advantages of parallel connection of laminated battery pole pieces and other advantages, but also solves the low production efficiency and easy misalignment risk. Among them, the efficiency advantage is: each layer of stacked pole pieces is made into a battery cell by winding, that is, the efficiency of winding is used to complete the laminated battery cell structure. Structural advantage: multi-layer wrapping, overall tightening, each layer is constrained by the diaphragm and cannot move, so it is not easy to dislocate and safety is guaranteed.

[0033] Please refer to Figures 1 to 3 The method for manufacturing a battery cell according to an embodiment of the present application includes:

[0034] A diaphragm G0 is provided, and there are n laminated areas A1, A2, A3, A4, A5, A6, A7, ..., A38, A39, A40, A41 in sequence from the starting position of the diaphragm G0 (n is determined according to the number of positive and negative electrodes required by the actual battery cell. In this embodiment, n=41). The upper and lower surfaces of the diaphragm G0 in the laminated areas A1, A2, A3, A4, A5, A6, A7, ..., A38, A39, A40, A41 are coated with glue for bonding the electrodes; wherein the odd-numbered laminated areas A1, A3, A5 The length D1, D3, D5, D7, ..., D39 of the diaphragm between the even-numbered lamination areas A2, A4, A6, ..., A38, A40 and the next lamination area A2, A4, A6, ..., A38, A40 is equal to the sum of the lengths of the two lamination areas and the length of the diaphragm used for winding. The length D2, D4, D6, ..., D40 (not shown in the figure) of the diaphragm between the even-numbered lamination areas A2, A4, A6, ..., A38, A40 and the next lamination area A3, A5, A7, ..., A39, A41 is equal to the length of the diaphragm used for winding.

[0035] Adhere n pairs of first pole pieces P1 and second pole pieces P2 to the upper and lower surfaces of the diaphragm G0 of the n lamination areas A1, A2, A3, A4, A5, A6, A7, ..., A38, A39, A40, A41, respectively, to form n lamination units C1, C2, C3, C4, C5, C6, C7, ..., C38, C39, C40, C41; wherein the odd-numbered lamination units C1, C3, C5, C7, ..., C39, C41 are, from top to bottom, the first pole piece P1, the diaphragm G0, and the second pole piece P2, and the even-numbered lamination units C2, C4, C6, ..., C38, C40 are, from top to bottom, the second pole piece P2, the diaphragm G0, and the first pole piece P1;

[0036] Glue is sprayed on the upper and lower surfaces of the diaphragm G0 between the laminated areas A1, A2, A3, A4, A5, A6, A7, ..., A38, A39, A40, and A41, and the diaphragm G0 is wound from the first laminated unit C1 to the nth laminated unit C41 so that each laminated unit C1, C2, C3, C4, C5, C6, C7, ..., C38, C39, C40, and C41 are adhered to the surface of the diaphragm G0 to form a stacked battery cell. It should be noted that the length of the diaphragm used for winding is adapted to the thickness and number of the pole pieces to be wrapped during winding, as well as the thickness and number of the diaphragm layers. That is, the lengths D1, D3, D5, D7, ..., D39 of the diaphragms between each odd-numbered lamination region and the next lamination region are not equal. Similarly, the lengths D2, D4, D6, ..., D40 of the diaphragms between each even-numbered lamination region and the next lamination region are also not equal. This will be described in detail later. In addition, since the diaphragms in the lamination region are used to bond the pole pieces, the length of the lamination region needs to be adapted to the width of the pole pieces (e.g., equal to or slightly larger than) so that the pole pieces can be fully bonded to the diaphragm surface of the lamination region.

[0037] The winding direction of the first electrode sheet P1, the second electrode sheet P2, and the separator G0 is determined by the electrode sheet stacking structure of the actual battery cell. In this embodiment, the first electrode sheet P1 is the positive electrode sheet, and the second electrode sheet P2 is the negative electrode sheet. The width of the negative electrode sheet is greater than that of the positive electrode sheet. The winding direction is clockwise, as indicated by the broad arrow in the figure.

[0038] To implement the above-mentioned battery cell manufacturing method, the battery cell manufacturing system of this embodiment includes: a glue spraying device S1 (please refer to Figure 1 and Figure 4 ), used to spray glue on the upper and lower surfaces of the diaphragm G0; lamination device S2 (please refer to Figure 5 ), which is arranged in the lamination area and is used to bond the pole pieces P1 and P2 to the diaphragm G0.

[0039] During specific implementation, the glue spraying device S1 first sprays glue on the upper and lower surfaces of the diaphragm G0, and the lamination device S2 adheres the pole pieces P1 and P2 to the diaphragm G0 respectively. The lamination unit C1 of the first lamination area A1 is an upper positive pole piece and a lower negative pole piece; after two lamination positions (no pole piece is stacked), that is, a diaphragm G0 with a spacing of D1 length, the lamination unit C2 of the second lamination area A2 is an upper negative pole piece and a lower positive pole piece, and the lamination unit C3 of the third lamination area A3 is an upper positive pole piece and a lower negative pole piece after the adjacent lamination position, that is, a diaphragm G0 with a spacing of D2 length; after two more lamination positions (no pole piece is stacked), that is, a diaphragm G0 with a spacing of D3 length, the lamination unit C3 of the fourth lamination area A4 is a positive pole piece. The sheet unit C4 is the upper negative electrode sheet and the lower positive electrode sheet. The adjacent lamination position, i.e., the separator G0 with a length of interval D4, is the lamination unit C5 of the fifth lamination area A5, which is the upper positive electrode sheet and the lower negative electrode sheet. This process is analogous to the above, until the required number of layers is reached. For example, in this embodiment, the lamination unit C40 of the 40th lamination area A40 is the upper negative electrode sheet and the lower positive electrode sheet. The adjacent lamination position, i.e., the separator G0 with a length of interval D40, is the lamination unit C41 of the 41st lamination area A41, which is the upper positive electrode sheet and the lower negative electrode sheet. Each lamination position can begin lamination simultaneously, that is, all lamination is completed at once. Therefore, a lamination device S2 can be set up in each of the n lamination areas, and the lamination device S2 of each lamination area can perform lamination simultaneously.

[0040] After lamination, the film is wound clockwise from the lamination unit C1 to the lamination unit C41. During the winding process, the glue spraying device S1 sprays glue on the upper and lower surfaces of the diaphragm G0 between the lamination areas. Figure 1 Only the number of pole pieces and diaphragm layers of the laminated sheet during each winding is shown. The specific structure of the laminated sheet unit and diaphragm after winding can be referred to in the following table. Figure 2 and Figure 3 A magnified partial view is shown, and the process continues until all stacked cells are rolled and bonded to the separator G0. Finally, a circle of separator G0 is wrapped around the cells, and the separator is cut to form a wound cell. After the cells are glued, they are transferred to the next process using a fixture. In this embodiment, the winding process uses a flat winding needle, which is easier to operate than oval or round winding needles.

[0041] As mentioned above, the lengths D1, D3, D5, D7, ..., D39 of the diaphragm G0 between each odd-numbered lamination region and the next lamination region are not equal. Similarly, the lengths D2, D4, D6, ..., D40 of the diaphragm G0 between each even-numbered lamination region and the next lamination region are not equal. Specifically, the diaphragm between the lamination regions is actually the part of the diaphragm that does not adhere to the pole piece. The length calculation of each diaphragm that does not adhere to the pole piece is roughly as follows: Figure 2 and Figure 3 , taking the first electrode P1 as the positive electrode, the second electrode P2 as the negative electrode, the width of the negative electrode being greater than the width of the positive electrode, and the winding direction being clockwise as an example:

[0042] D1=D1a+D1b, where

[0043] D1a = x1 + negative electrode sheet width + y1 + diaphragm coating margin = negative electrode sheet thickness + negative electrode sheet width + (negative electrode sheet thickness + positive electrode sheet thickness + diaphragm thickness) + diaphragm coating margin;

[0044] D1b = negative electrode sheet width + z1 + diaphragm coating margin = negative electrode sheet width + (negative electrode sheet thickness + positive electrode sheet thickness * 2 + diaphragm thickness * 2) + diaphragm coating margin;

[0045] D2 = x2 + diaphragm coating margin = (negative electrode sheet thickness * 2 + positive electrode sheet thickness * 2 + diaphragm thickness * 3) + diaphragm coating margin;

[0046] D4 = x4 + diaphragm coating allowance = (negative electrode sheet thickness * 4 + positive electrode sheet thickness * 4 + diaphragm thickness * 7) + diaphragm coating allowance;

[0047] D5=D5a+D5b,where

[0048] D5a = x5 + negative electrode sheet width + y5 + diaphragm coating allowance = (negative electrode sheet thickness * 5 + positive electrode sheet thickness * 4 + diaphragm thickness * 8) + negative electrode sheet width + (negative electrode sheet thickness * 5 + positive electrode sheet thickness * 5 + diaphragm thickness * 9) + diaphragm coating allowance;

[0049] D5b = negative electrode sheet width + z5 + diaphragm coating margin = negative electrode sheet width + (negative electrode sheet thickness * 5 + positive electrode sheet thickness * 6 + diaphragm thickness * 10) + diaphragm coating margin;

[0050] D6 = x6 + diaphragm coating allowance = (negative electrode sheet thickness * 6 + positive electrode sheet thickness * 6 + diaphragm thickness * 11) + diaphragm coating allowance;

[0051] And so on.

[0052] In the above formulas, the "membrane covering margin" may be different, which can be understood as the margin left for covering all current pole pieces and membranes during winding.

[0053] It can be understood from the above formulas that the length of the diaphragm between the odd-numbered lamination area and the next lamination area is equal to the sum of the lengths of the two lamination areas and the length of the diaphragm used for winding, and the length of the diaphragm between the even-numbered lamination area and the next lamination area is equal to the length of the diaphragm used for winding; wherein, the length of the lamination area is adapted to the width of the electrode so that the electrode can be completely bonded to the diaphragm surface of the lamination area. In this embodiment, the length of the lamination area is equal to the width of the negative electrode; the length of the diaphragm used for winding is adapted to the thickness and number of the electrode to be covered for winding, as well as the thickness and number of diaphragm layers. As can be seen from the figure, the number of covered electrode sheets and the number of diaphragm layers are different each time half a circle is wound.

[0054] Furthermore, this embodiment uses a new glue, the components of which include acetonitrile and polyethylene oxide (PEO), and have a clear appearance and are free of impurities. Based on considerations such as bonding effect and not affecting the characteristics of the battery core, the mass ratio of the glue is: PEO / (acetonitrile + PEO) = 6% to 15%, and the viscosity of the glue is 100mPa.s (milliPascals.seconds) to 150mPa.s. Because the viscosity is too low, the diaphragm bonding effect is poor, and if the viscosity is too high, the fluidity is poor, and colloid particles are easily formed at the glue nozzle. Nitriles are an organic solvent that is suitable for high voltages and generally have excellent properties such as a wide electrochemical window, high anode stability, low viscosity, and a high boiling point. They are beneficial to the film formation effect of the solid electrolyte interface film (SEI) and can also improve battery safety. The glue will dissolve in the electrolyte, so it will not affect the internal resistance of the battery and the interface contact. It will not block ion channels.

[0055] Please refer to Figure 4 In the battery cell manufacturing system of this embodiment, the glue spraying device S1 includes a glue storage tank S11 and a glue spraying nozzle S12 mounted on the glue storage tank S11. The glue storage tank S11 is used to store glue, and the glue is applied to the surface of the diaphragm G0 through the glue spraying nozzle S12. The glue spraying nozzles S12 are respectively provided on the upper and lower surfaces of the diaphragm G0.

[0056] The glue spraying device S1 sprays glue on the upper and lower surfaces of the diaphragm G0 in the laminated area in sequence when the diaphragm is unwound, and sprays glue on the upper and lower surfaces of the diaphragm G0 between the laminated areas when the diaphragm G0 is wound. Specifically, the glue spraying device S1 can be set at the position where the diaphragm G0 is unwound from the diaphragm roll. When the diaphragm G0 starts to be pulled, that is, when the diaphragm is unwound, all nozzles S12 spray glue at a certain interval in the transverse direction at the same time, that is, glue is sprayed on the upper and lower surfaces of the diaphragm G0 in the laminated area, and the interval area of ​​the laminated area is not sprayed first. The glue spraying stops after the diaphragm G0 is pulled into place. When the diaphragm G0 starts to be wound, the glue spraying device S1 can be set between the laminated areas to spray glue on the upper and lower surfaces of the diaphragm G0, that is, when the diaphragm G0 has a longitudinal movement, glue spraying starts in the interval area of ​​the laminated area, and the glue spraying stops when the diaphragm G0 stops moving. The glue spraying needs to be kept uniform, continuous and uninterrupted, and well-fitted. The amount of glue sprayed should be based on sticking to the pole piece and preventing the pole piece from falling off or shifting during the winding process or when the diaphragm shakes.

[0057] Please continue to refer to Figure 5 In the battery cell manufacturing system of this embodiment, the lamination device S2 includes: electrode material boxes S21, S22, electrode positioning mechanisms S31, S32, and electrode feeding mechanisms S41, S42. To clearly show the structure of the lamination device S5, Figure 5 Only the lamination devices S2 provided in lamination areas A4 and A5 are shown. In actual implementation, a lamination device S2 can be provided in each lamination area. The lamination devices S2 in n lamination areas can perform lamination simultaneously, that is, the first pole piece P1 and the second pole piece P2 are laminated and bonded to the upper and lower surfaces of the diaphragm G0. Furthermore, diaphragm-fixing rollers S5 can be provided above and below the diaphragm G0 on both sides of each lamination area to ensure the flatness and fixed position of the diaphragm G0.

[0058] The electrode positioning mechanisms S31 and S32 are used to position the electrode sheets delivered by the electrode material boxes S21 and S22 and transfer them to the feeding mechanisms S41 and S42. The feeding mechanisms S41 and S42 are used to absorb the electrode sheets and adhere the electrode sheets to the surface of the diaphragm G0 in the lamination area. After spraying the glue, the electrode material boxes S21 and S22 above and below the diaphragm G0 simultaneously deliver the electrode sheets. The electrode positioning mechanisms S31 and S32 first position the electrode sheets and then transfer them to the suction plates of the feeding mechanisms S41 and S42. The upper and lower feeding mechanisms S41 and S42 absorb the electrode sheets and move them up and down to adhere to the diaphragm G0 and apply pressure to ensure a firm bond. After that, the vacuum is broken and the feeding mechanisms S41 and S42 return to their positions to absorb the next electrode sheet.

[0059] Specifically, according to different positions: in the even-numbered lamination area, e.g. Figure 5In the A4 area, the lamination device S2 above the diaphragm G0 includes a second electrode material box S22, a second electrode positioning mechanism S32 and an upper feeding mechanism S41. The second electrode positioning mechanism S32 positions the second electrode P2 delivered by the second electrode material box S22 and transfers it to the upper feeding mechanism S41. The upper feeding mechanism S41 absorbs the second electrode P2, and then adheres the second electrode P2 to the upper surface of the diaphragm G0 and presses it tightly. The lamination device S2 below the diaphragm G0 includes a first electrode material box S21, a first electrode positioning mechanism S31 and a lower feeding mechanism S42. The first electrode positioning mechanism S31 positions the first electrode P1 delivered by the first electrode material box S21 and transfers it to the lower feeding mechanism S42. The lower feeding mechanism S42 absorbs the first electrode P1, and then adheres the first electrode P1 to the lower surface of the diaphragm G0 and presses it tightly. In the odd-numbered lamination areas, for example Figure 5 In the A5 area, the stacking device S2 above the diaphragm G0 includes a first electrode sheet material box S21, a first electrode sheet positioning mechanism S31 and an upper electrode sheet feeding mechanism S41. The first electrode sheet positioning mechanism S31 positions the first electrode sheet P1 sent out from the first electrode sheet material box S21 and transfers it to the upper electrode sheet feeding mechanism S41. The upper electrode sheet feeding mechanism S41 absorbs the first electrode sheet P1, and then adheres the first electrode sheet P1 to the upper surface of the diaphragm G0 and presses it; the stacking device S2 below the diaphragm G0 includes a second electrode sheet material box S22, a second electrode sheet positioning mechanism S32 and a lower electrode sheet feeding mechanism S42. The second electrode sheet positioning mechanism S32 positions the second electrode sheet P2 sent out from the second electrode sheet material box S22 and transfers it to the lower electrode sheet feeding mechanism S42. The lower electrode sheet feeding mechanism S42 absorbs the second electrode sheet P2, and then adheres the second electrode sheet P2 to the lower surface of the diaphragm G0 and presses it.

[0060] In summary, after reading this detailed disclosure, those skilled in the art will appreciate that the foregoing detailed disclosure may be presented by way of example only and may not be limiting. Although not expressly stated herein, those skilled in the art will understand that this application is intended to encompass various reasonable changes, improvements, and modifications to the embodiments. Such changes, improvements, and modifications are intended to be suggested by this disclosure and are within the spirit and scope of the exemplary embodiments of the present disclosure.

[0061] In addition, certain terms in this application have been used to describe embodiments of the present disclosure. For example, "one embodiment," "an embodiment," and / or "some embodiments" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present disclosure. Therefore, it can be emphasized and should be understood that two or more references to "an embodiment" or "one embodiment" or "an alternative embodiment" in various parts of this specification do not necessarily refer to the same embodiment. In addition, particular features, structures, or characteristics may be appropriately combined in one or more embodiments of the present disclosure.

[0062] It should be understood that in the foregoing description of the embodiments of the present disclosure, in order to help understand a feature and for the purpose of simplifying the present disclosure, the present application sometimes combines various features in a single embodiment, drawing or its description. Alternatively, the present application disperses various features across multiple embodiments of the present application. However, this does not mean that the combination of these features is necessary. When reading this application, it is entirely possible for those skilled in the art to extract some of the features and understand them as separate embodiments. In other words, the embodiments in the present application can also be understood as the integration of multiple secondary embodiments. This is also true when the content of each secondary embodiment is less than all the features of a single aforementioned disclosed embodiment.

[0063] In some embodiments, numbers expressing quantities or properties used to describe and claim certain embodiments of the present application should be understood as being modified in some cases by the terms "about," "approximately," or "substantially." For example, unless otherwise indicated, "about," "approximately," or "substantially" can represent a ±20% variation of the value it describes. Therefore, in some embodiments, the numerical parameters listed in the written description and the appended claims are approximate values ​​that can vary depending on the desired properties that a particular embodiment is attempting to obtain. In some embodiments, numerical parameters should be interpreted in light of the number of reported significant digits and by applying ordinary rounding techniques. Although some embodiments of the present application set forth a wide range of numerical ranges and parameters are approximate, the specific examples are listed as precisely as possible.

[0064] Each patent, patent application, patent application publication, and other materials, such as articles, books, specifications, publications, documents, articles, etc., cited herein is hereby incorporated by reference in its entirety for all purposes, except for any prosecution document history related thereto, any equivalent that may be inconsistent or conflicting with this document, or any equivalent prosecution document history that may have a limiting effect on the broadest scope of the claims now or hereafter associated with this document. For example, if there is any inconsistency or conflict between the description, definition, and / or use of terms associated with any incorporated material and the terminology, description, definition, and / or use associated with this document, the terminology in this document shall control.

[0065] Finally, it should be understood that the embodiments of the application disclosed herein are illustrations of the principles of the embodiments of the present application. Other modified embodiments are also within the scope of the present application. Therefore, the embodiments disclosed in the present application are merely examples and not limitations. Those skilled in the art can adopt alternative configurations based on the embodiments in the present application to implement the applications in the present application. Therefore, the embodiments of the present application are not limited to the embodiments that have been precisely described in the application.

Claims

1. A method for manufacturing a battery cell, characterized in that: include: A diaphragm is provided, wherein n lamination regions are sequentially provided from a starting position of the diaphragm, and glue is applied to the upper and lower surfaces of the diaphragms of the lamination regions for bonding the pole pieces, wherein the length of the diaphragm between an odd-numbered lamination region and the next lamination region is equal to the sum of the lengths of the two lamination regions and the length of the diaphragm for winding, and the length of the diaphragm between an even-numbered lamination region and the next lamination region is equal to the length of the diaphragm for winding; Adhere n pairs of first and second pole pieces to the upper and lower surfaces of the diaphragm in the n lamination areas, respectively, to form n lamination units; wherein the odd-numbered lamination units are, from top to bottom, the first pole piece, the diaphragm, and the second pole piece, and the even-numbered lamination units are, from top to bottom, the second pole piece, the diaphragm, and the first pole piece; Laminating devices are respectively provided in n lamination areas, and glue spraying devices spray glue on the upper and lower surfaces of the diaphragms in the lamination areas in sequence when the diaphragms are unwound, and the lamination devices of the n lamination areas perform lamination simultaneously; when the diaphragms are wound, glue is sprayed on the upper and lower surfaces of the diaphragms between the lamination areas, and the diaphragms are wound from the first lamination unit to the nth lamination unit so that each lamination unit is adhered to the surface of the diaphragm to form a stacked battery cell; The length of the diaphragm used for winding is adapted to the thickness and number of the pole pieces required for winding and the thickness and number of layers of the diaphragm.

2. The method for manufacturing a battery cell according to claim 1, wherein: The first electrode sheet is a positive electrode sheet, the second electrode sheet is a negative electrode sheet, the width of the negative electrode sheet is greater than the width of the positive electrode sheet; and the winding direction is clockwise.

3. The method for manufacturing a battery cell according to claim 1, wherein: The glue comprises acetonitrile and polyethylene oxide.

4. The method for manufacturing a battery cell according to claim 3, wherein: The mass ratio of the glue is: polyethylene oxide / (acetonitrile+polyethylene oxide) is 6% to 15%, and the viscosity of the glue is 100 mPa.s to 150 mPa.s.

5. The method for manufacturing a battery cell according to claim 1, wherein: The winding adopts a flat winding needle.

6. A battery cell manufacturing system, applicable to the battery cell manufacturing method according to any one of claims 1 to 5, characterized in that: include: Glue spraying device, used for spraying glue on the upper and lower surfaces of the diaphragm; A lamination device is arranged in the lamination area and is used to bond the pole piece to the diaphragm; a lamination device is respectively arranged in n lamination areas, and the lamination devices of the n lamination areas perform lamination simultaneously; a glue spraying device sprays glue on the upper and lower surfaces of the diaphragm in the lamination area in sequence when the diaphragm is unwound, and sprays glue on the upper and lower surfaces of the diaphragm between the lamination areas when the diaphragm is wound.

7. The battery cell production system according to claim 6, characterized in that: The glue spraying device comprises a glue storage tank and a glue spraying nozzle installed on the glue storage tank.

8. The battery cell manufacturing system according to claim 6, characterized in that: The lamination device includes: a pole piece material box, a pole piece positioning mechanism and a pole piece feeding mechanism. The pole piece positioning mechanism is used to position the pole pieces fed out of the pole piece material box and transfer them to the pole piece feeding mechanism. The pole piece feeding mechanism is used to absorb the pole pieces and bond them to the diaphragm surface of the lamination area.

9. The battery cell manufacturing system according to claim 6, characterized in that: Also includes: Diaphragm fixing rollers are arranged above and below the diaphragms on both sides of the lamination area.

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