Stacked battery cell, and fabrication apparatus and method therefor

Abstract

A stacked battery cell, and a fabrication apparatus and method therefor. The stacked battery cell is fabricated by folding a battery cell structure. The battery cell structure comprises first electrode plates, a separator and second electrode plates. Each first electrode plate is located on one side of the separator, and is connected to the separator via a normal-temperature and normal-pressure electrically conductive adhesive. A plurality of second electrode plates are each alternately arranged on the side of the separator away from the respective first electrode plate, and the second electrode plates are each bonded to the separator via a normal-temperature and normal-pressure electrically conductive adhesive. The normal-temperature and normal-pressure electrically conductive adhesive has good bonding performance and electrical conductivity, improves the electrolyte absorption and alleviates interface defects in batteries, and enhances battery performance.

Description

Laminated cell and preparation equipment and method thereof

[0001] The present application claims priority to Chinese patent applications No. 202422416488.8 and 202411389163.3, filed on September 30, 2024, with the Chinese Patent Office, the contents of which are incorporated herein by reference in their entirety. TECHNICAL FIELD

[0002] The present application belongs to the technical field of battery processing, and particularly relates to a laminated cell and a preparation equipment and method thereof. BACKGROUND

[0003] The laminated cell of the lithium battery is prepared by Z-type laminating process. The Z-type laminating process is to laminate the positive electrode sheet, the negative electrode sheet and the separator through a thermal compounding process, and then to form a core package by Z-type stacking.

[0004] Currently, the technology of laminating the electrode sheet and the separator is to coat a hot melt adhesive on the separator, and then to laminate the separator and the electrode sheet together through the adhesive by a hot pressing process. However, in the hot pressing process, the temperature of the compounding roller exceeds 50℃ and the pressure needs to exceed 1.2T, so that the separator and the electrode sheet can be pressed together under the action of high temperature and high pressure. SUMMARY

[0005] However, the glue particles on the separator will be flattened, resulting in a decrease in the air permeability of the separator, affecting the liquid absorption effect of the battery. After formation and full charging, the battery interface is prone to interface defects such as purple spots and black spots, resulting in poor battery performance.

[0006] In a first aspect, the present application provides a laminated cell, which is prepared by folding the cell structure. The cell structure comprises:

[0007] a first electrode sheet;

[0008] a separator, the first electrode sheet being arranged on one side of the separator, and the first electrode sheet and the separator being connected by a normal temperature and pressure conductive adhesive;

[0009] a second electrode sheet, the second electrode sheet being arranged on the side of the separator away from the first electrode sheet, and the second electrode sheet and the separator on the side being connected by a normal temperature and pressure conductive adhesive.

[0010] In a second aspect, the present application provides a preparation equipment of a laminated cell, comprising:

[0011] a first electrode sheet preparation unit arranged to prepare the first electrode sheet;

[0012] a first glue spraying mechanism arranged downstream of the first electrode sheet preparation unit and arranged to spray a normal temperature and pressure conductive adhesive on the surface of the first electrode sheet;

[0013] The diaphragm unwinding mechanism is arranged downstream of the first glue spraying mechanism and is configured to deliver the diaphragm.

[0014] The first composite mechanism is arranged downstream of the diaphragm unwinding mechanism and includes two oppositely arranged first pressure rollers. After the first pole piece and the diaphragm pass through the first pressure rollers, a first composite belt is prepared. The pressure applied by the first pressure rollers is P1, wherein 0.05T≤P1≤0.1T.

[0015] The second pole piece preparation unit is arranged downstream of the first composite mechanism and is configured to prepare a second pole piece.

[0016] The second glue spraying mechanism is arranged downstream of the second pole piece preparation unit and is configured to spray the normal-temperature and normal-pressure conductive adhesive on the surface of the second pole piece connected with the first composite belt.

[0017] The second composite mechanism is arranged downstream of the second glue spraying mechanism and includes two oppositely arranged second pressure rollers. After the first composite belt and the second pole piece pass through the second pressure rollers, an electric core structure is prepared. The pressure applied by the second pressure rollers is P2, wherein 0.05T≤P2≤0.1T.

[0018] The folding mechanism is configured to fold the electric core structure to prepare a laminated core.

[0019] In a third aspect, the embodiments of the present application further provide a preparation method of a laminated core, including the following steps:

[0020] The first pole piece and the second pole piece are prepared.

[0021] The normal-temperature and normal-pressure conductive adhesive is sprayed on the two side surfaces of the first pole piece, the first pole piece is connected with two diaphragms in a composite manner, the normal-temperature and normal-pressure conductive adhesive is sprayed on one side surface of the second pole piece, and the second pole piece is connected with the diaphragm away from the first pole piece in a composite manner, so as to prepare an electric core structure.

[0022] The electric core structure is folded to prepare a laminated core. Advantages

[0023] The laminated core, the preparation equipment and the preparation method provided by the embodiments of the present application include a first pole piece, a second pole piece and a diaphragm. The first pole piece and the diaphragm are connected in a composite manner by using normal-temperature and normal-pressure conductive adhesive. The second pole piece and the diaphragm are connected in a composite manner by using normal-temperature and normal-pressure conductive adhesive. The normal-temperature and normal-pressure conductive adhesive has good adhesive properties at normal temperature and normal pressure and also has good conductive properties. The present application improves the situation that the high-temperature and high-pressure thermal composite of the pole piece and the diaphragm during the processing of the laminated core leads to poor battery performance, improves the liquid absorption effect and the interface defect of the battery, and improves the battery performance. BRIEF DESCRIPTION OF DRAWINGS

[0024] Fig. 1 is a cross-sectional view of a first form of a laminated battery cell according to some embodiments of the present application.

[0025] Fig. 2 is a cross-sectional view of a second form of a laminated battery cell according to some embodiments of the present application.

[0026] Fig. 3 is a cross-sectional view of a third form of a laminated battery cell according to some embodiments of the present application.

[0027] Fig. 4 is a cross-sectional view of a first form of a battery cell structure according to some embodiments of the present application.

[0028] Fig. 5 is a cross-sectional view of a second form of a battery cell structure according to some embodiments of the present application.

[0029] Fig. 6 is a cross-sectional view of a third form of a battery cell structure according to some embodiments of the present application.

[0030] Fig. 7 is a schematic view of a manufacturing apparatus for a laminated battery cell according to some embodiments of the present application.

[0031] Reference signs are:

[0032] 10, laminated battery cell; 110, first electrode plate; 120, separator; 121, first separator; 122, second separator; 130, second electrode plate;

[0033] 100, first electrode plate manufacturing unit; 200, first glue spraying mechanism; 300, separator unwinding mechanism; 400, first compounding mechanism; 410, first pressure roller; 500, second electrode plate manufacturing unit; 600, second glue spraying mechanism; 700, second compounding mechanism; 710, second pressure roller; 800, folding mechanism. Embodiments of the present application

[0034] Referring to Figs. 1, 2, 3, 4, 5 and 6, some embodiments of the present application provide a laminated battery cell 10, which is manufactured by folding a battery cell structure including a first electrode plate 110, a separator 120 and a second electrode plate 130. The first electrode plate 110 is disposed on one side of the separator 120, and the first electrode plate 110 is connected to the separator 120 by a normal-temperature and normal-pressure conductive adhesive. In some embodiments, the normal-temperature and normal-pressure conductive adhesive is PVDF-HFP (polyvinylidene fluoride-hexafluoropropylene). The second electrode plate 130 is disposed on the side of the separator 120 facing away from the first electrode plate 110, and the second electrode plate 130 is connected to the separator 120 by a normal-temperature and normal-pressure conductive adhesive. The first electrode plate 110 and the second electrode plate 130 have opposite polarities. The first electrode plate 110 is provided with a first tab, and the second electrode plate 130 is provided with a second tab, and the first tab and the second tab extend out of the separator 120.

[0035] In some embodiments of the present application, the first pole piece 110 and the second pole piece 130 are connected with the diaphragm 120 by a normal temperature and pressure conductive adhesive. In the process of compounding the first pole piece 110, the second pole piece 130 and the diaphragm 120, high temperature and high pressure are not required. Under normal temperature and pressure (temperature of 25°C and pressure of 1.01325 Pa), the effect of bonding the first pole piece 110, the second pole piece 130 and the diaphragm 120 can be achieved, and the processing process is simple, and the investment in processing equipment is reduced.

[0036] In some embodiments, the normal temperature and pressure conductive adhesive is PVDF-HFP. PVDF-HFP has good cohesion and good bonding effect under normal temperature and pressure. The conductivity of PVDF-HFP is as high as 3.2 ms / cm at room temperature (25°C), the electrochemical temperature window can reach 5V, the lithium ion transference number is 0.63, and it has good interface compatibility with lithium metal. Thus, the cycle stability and safety of the lithium battery are improved.

[0037] In some embodiments, referring to FIGS. 1 and 4, two diaphragms 120 are provided in the structure of the battery cell, which are a first diaphragm 121 and a second diaphragm 122, and the first diaphragm 121 and the second diaphragm 122 are oppositely spaced. The first diaphragm 121 and the second diaphragm 122 both extend along the first direction. The first diaphragm 121 and the second diaphragm 122 have the same shape and size. The first pole piece 110 is located between the first diaphragm 121 and the second diaphragm 122. Along the first direction, the first pole pieces 110 are spaced apart, and the two side surfaces of the first pole piece 110 are coated with a normal temperature and pressure conductive adhesive. One side surface of the first pole piece 110 is bonded to the first diaphragm 121 by the normal temperature and pressure conductive adhesive, and the other side surface of the first pole piece 110 is bonded to the second diaphragm 122 by the normal temperature and pressure conductive adhesive. The second pole piece 130 is arranged on the side of the first diaphragm 121 away from the first pole piece 110 and on the side of the second diaphragm 122 away from the first pole piece 110. Along the first direction, the second pole pieces 130 on the side of the first diaphragm 121 and the second pole pieces 130 on the side of the second diaphragm 122 are alternately arranged.

[0038] For example, referring to FIGS. 1 and 4, the first pole piece 110 and the second pole piece 130 are both single electrodes, a plurality of first pole pieces 110 are spaced apart along the first direction, and a plurality of second pole pieces 130 are spaced apart along the first direction. The first pole piece 110 and the second pole piece 130 are arranged in alignment. The first direction is the X-axis direction. When the first pole piece 110 is a negative pole piece, the second pole piece 130 is a positive pole piece. When the first pole piece 110 is a positive pole piece, the second pole piece 130 is a negative pole piece.

[0039] Referring to FIGS. 4 and 5, along the first direction, the adjacent negative electrode sheets are spaced apart by a distance. Both sides of the negative electrode sheet are coated with a room temperature and normal pressure conductive adhesive, and the two sides of the negative electrode sheet are respectively attached to the first separator 121 and the second separator 122. One side of the positive electrode sheet is coated with a room temperature and normal pressure conductive adhesive, and the positive electrode sheet is attached to the separator 120 on the side. Along the thickness direction of the negative electrode sheet, the negative electrode sheet is arranged opposite to the positive electrode sheet. The positive electrode sheet and the negative electrode sheet are both rectangular sheet structures, the length dimension of the positive electrode sheet is smaller than the length dimension of the negative electrode sheet, and the width dimension of the positive electrode sheet is smaller than the width dimension of the negative electrode sheet. The projection of all negative electrode sheets in the separator 120 falls within the range of the separator 120.

[0040] In some embodiments, the first electrode sheet 110 is a positive electrode sheet, and the second electrode sheet 130 is a negative electrode sheet. Along the first direction, a plurality of positive electrode sheets are sequentially and spaced apart. The number of second electrode sheets 130 is two more than the number of first electrode sheets 110. Along the thickness direction, the second electrode sheet 130 is arranged opposite to the first electrode sheet 110, and the projection of the first electrode sheet 110 completely falls within the projection range of the second electrode sheet 130. The two side surfaces of the positive electrode sheet are sprayed with a room temperature and normal pressure conductive adhesive, and the positive electrode sheet is attached to the first separator 121 and the second separator 122 on both sides. The negative electrode sheet is arranged on the side of the first separator 121 away from the positive electrode sheet and the side of the second separator 122 away from the positive electrode sheet. Along the first direction, the negative electrode sheet on the side of the first separator 121 and the negative electrode sheet on the side of the second separator 122 are arranged alternately.

[0041] In some embodiments, the first electrode sheet 110 is a negative electrode sheet, and the second electrode sheet 130 is a positive electrode sheet.

[0042] For example, referring to FIGS. 2 and 5, along the first direction, the adjacent negative electrode sheets are connected. A plurality of first electrode sheets 110 are connected to form a long strip-shaped structure, and the first electrode sheet 110 is a continuous structure. The size of the first electrode sheet 110 is smaller than the size of the separator 120. The projection of the first electrode sheet 110 on the separator 120 completely falls within the range of the separator 120. Both sides of the first electrode sheet 110 are coated with a room temperature and normal pressure conductive adhesive, and the first electrode sheet 110 is attached to the separator 120. Alternatively, the region of the first electrode sheet 110 opposite to the second electrode sheet 130 is coated with a room temperature and normal pressure conductive adhesive, and within the range of the adhesive, the electrode sheet 110 is attached to the separator 120. Along the first direction, the projections of the positive electrode sheets on the first separator 120 are sequentially and spaced apart, and the distance between any adjacent positive electrode sheets is the same.

[0043] In some embodiments, referring to FIG. 3 and FIG. 6, a plurality of first electrode tabs 110, one diaphragm 120 and a plurality of second electrode tabs 130 are arranged in the cell structure. The first electrode tabs 110 are arranged on one side of the diaphragm 120, and the first electrode tabs 110 are arranged at intervals along a first direction. The second electrode tabs 130 are arranged on the other side of the diaphragm 120, and the second electrode tabs 130 are arranged at intervals along the first direction. Along the first direction, the first electrode tabs 110 and the second electrode tabs 130 are arranged alternately at intervals. One side surface of the first electrode tab 110 is connected to one side surface of the diaphragm 120 by the room temperature and pressure conductive adhesive, and the second electrode tab 130 is arranged on the other side of the diaphragm 120. One side surface of the second electrode tab 130 is connected to the other side surface of the diaphragm 120 by the room temperature and pressure conductive adhesive.

[0044] Referring to FIG. 7, the application also provides a preparation device of the laminated cell, which comprises a first electrode tab preparation unit 100, a first glue spraying mechanism 200, a diaphragm unwinding mechanism 300, a first compounding mechanism 400, a second electrode tab preparation unit 500, a second glue spraying mechanism 600, a second compounding mechanism 700 and a folding mechanism 800 arranged in sequence along a production line.

[0045] In some embodiments, referring to FIG. 7, the first electrode tab preparation unit 100 is arranged to prepare the first electrode tab 110. The first electrode tab preparation unit 100 comprises an unwinding mechanism and a cutting mechanism. The unwinding mechanism is wound with an electrode tab roll. When the first electrode tab 110 is a positive electrode tab, the corresponding unwinding mechanism is wound with a positive electrode tab roll. When the first electrode tab 110 is a negative electrode tab, the corresponding unwinding mechanism is wound with a negative electrode tab roll. The cutting mechanism is arranged to cut the roll into a plurality of first electrode tabs 110. When the first electrode tab 110 is a positive electrode tab, the cutting mechanism cuts a plurality of positive electrode tabs. When the first electrode tab 110 is a negative electrode tab, the cutting mechanism cuts a plurality of negative electrode tabs or one continuous negative electrode tab.

[0046] In some embodiments, referring to FIG. 7, the first glue spraying mechanism 200 is arranged downstream of the first electrode tab preparation unit 100. The first glue spraying mechanism 200 is arranged to spray the room temperature and pressure conductive adhesive to the side surface of the cut first electrode tab 110 connected to the diaphragm 120. In some embodiments, the room temperature and pressure conductive adhesive is PVDF-HFP.

[0047] In some embodiments, referring to FIG. 7, the diaphragm unwinding mechanism 300 is arranged downstream of the first glue spraying mechanism 200. When two diaphragms 120 are arranged, the diaphragm unwinding mechanism 300 comprises a first diaphragm unwinding roll, a second diaphragm unwinding roll, and a cutting mechanism. The first diaphragm unwinding roll and the second diaphragm unwinding roll are wound with diaphragm rolls, the first diaphragm unwinding roll is arranged to unwind the diaphragm roll, and the first diaphragm 121 is cut by the cutting mechanism. The second diaphragm unwinding roll is arranged to unwind the diaphragm material, and the second diaphragm 122 is cut by the cutting mechanism. The first diaphragm unwinding roll is located on one side of the first pole piece 110, and the second diaphragm unwinding roll is located on the other side of the first pole piece 110. During the unwinding of the first diaphragm 121 and the second diaphragm 122, the first diaphragm 121 and the second diaphragm 122 are respectively connected to the first pole piece 110.

[0048] In some embodiments, referring to FIG. 7, the first compounding mechanism 400 is arranged downstream of the diaphragm unwinding mechanism 300. The first compounding mechanism 400 comprises two oppositely arranged first pressure rollers 410. The first pressure rollers 410 do not need to be heated, and compared with the compounding roller, the structure is simple and the maintenance is convenient. The first pole piece 110 and the diaphragm 120 after being glued are compounded into a first compounding belt by the first pressure rollers 410. The pressure applied by the first pressure rollers 410 is P1, wherein 0.05T≤P1≤0.1T. The value of P1 can be 0.05T, 0.06T, 0.75T, 0.08T, 0.95T, 0.1T or other values not listed. The pressure applied by the first pressure rollers 410 on the diaphragm 120 and the first pole piece 110 is small, which reduces the probability of damage to the conductive particles in the conductive adhesive at normal temperature and pressure due to excessive pressure, and ensures the conductivity of the conductive adhesive at normal temperature and pressure.

[0049] In some embodiments, referring to FIG. 7, the second pole piece preparation unit 500 is arranged downstream of the first compounding mechanism 400. The second pole piece preparation unit 500 comprises an unwinding mechanism and a cutting mechanism, and the unwinding mechanism is wound with a pole piece roll. When the second pole piece 130 is a positive pole piece, the corresponding pole piece roll is wound with a positive pole piece roll, and when the second pole piece 130 is a negative pole piece, the corresponding pole piece roll is wound with a negative pole piece roll. The cutting mechanism is arranged to cut the roll into a plurality of second pole pieces 130. The second pole piece preparation unit 500 is provided with two unwinding mechanisms and two cutting mechanisms, one of which is arranged on one side of the first pole piece 110. The other unwinding mechanism and cutting mechanism are arranged on the other side of the first pole piece 110.

[0050] In some embodiments, referring to FIG. 7, the second glue spraying mechanism 600 is arranged downstream of the second tab preparation unit 500. Two second glue spraying mechanisms 600 are arranged. One second glue spraying mechanism 600 is arranged on one side of the first tab 110, and the other second glue spraying mechanism 600 is arranged on the other side of the first tab 110. One second glue spraying mechanism 600 is arranged to spray the surface of the second tab 130 on the side of the first diaphragm 121 with the normal temperature and pressure conductive adhesive. The other is arranged to spray the surface of the second tab 130 on the side of the second diaphragm 122 with the normal temperature and pressure conductive adhesive. In some embodiments, the normal temperature and pressure conductive adhesive is PVDF-HFP.

[0051] In some embodiments, referring to FIG. 7, the second compounding mechanism 700 is arranged downstream of the second glue spraying mechanism 600. The second compounding mechanism 700 includes two oppositely arranged second pressure rollers 710. The first compounding belt and the second tab 130 are compounded into a battery cell structure after passing through the second pressure rollers 710. The pressure applied by the second pressure rollers 710 is P2, where 0.05T≤P2≤0.1T. The value of P2 can be 0.05T, 0.06T, 0.75T, 0.08T, 0.95T, 0.1T or other values not listed. The pressure applied by the second pressure rollers 710 on the second tab 130 and the first compounding belt is smaller, reducing the probability of damage to the conductive particles in the normal temperature and pressure conductive adhesive caused by excessive pressure, and ensuring the conductivity of the normal temperature and pressure conductive adhesive.

[0052] In some embodiments, the folding mechanism 800 is arranged downstream of the second compounding mechanism 700, and the folding mechanism 800 is arranged to fold the battery cell structure, which is a folded tab battery cell. For example, the folding mechanism 800 folds the battery cell structure in a zigzag shape.

[0053] In some embodiments of the present application, the first glue spraying mechanism 200 sprays the surface of the first tab 110 with the normal temperature and pressure conductive adhesive, and the second glue spraying mechanism 600 sprays the surface of the second tab 130 with the normal temperature and pressure conductive adhesive. The first compounding mechanism 400 applies a P1 pressure to the first tab 110 and the diaphragm 120, and the second compounding mechanism 700 applies a P2 pressure to the first tab 110, the diaphragm 120 and the second tab 130. The first compounding mechanism 400 and the second compounding mechanism 700 use pressure rollers without heating, and the normal temperature and pressure conductive adhesive is not affected by high temperature and high pressure. While ensuring the adhesion effect of the diaphragm 120 to the negative tab and the positive tab, the conductivity of the normal temperature and pressure conductive adhesive is ensured, and the performance of the battery is good.

[0054] In some embodiments, the first pole piece 110 is a negative pole piece, and the second pole piece 130 is a positive pole piece. The first pole piece preparation unit 100 can prepare a single-structure negative pole piece, or a continuous-structure negative pole piece. The single-structure negative pole piece refers to one negative pole piece corresponding to one positive pole piece. The continuous-structure negative pole piece refers to one negative pole piece corresponding to multiple positive pole pieces.

[0055] In some embodiments, referring to FIG. 7, two first glue spraying mechanisms 200 are provided, and the two first glue spraying mechanisms 200 are respectively configured to spray the normal-temperature and normal-pressure conductive adhesive to the two side surfaces of the first pole piece 110. For example, the first glue spraying mechanism 200 is provided on each side of the first pole piece 110, and the two first glue spraying mechanisms 200 simultaneously spray the normal-temperature and normal-pressure conductive adhesive to the two side surfaces of the cut first pole piece 110. In some embodiments, the normal-temperature and normal-pressure conductive adhesive is PVDF-HFP.

[0056] For example, referring to FIG. 7, two separators 120 are provided, which are a first separator 121 and a second separator 122. One side of the first pole piece 110 is connected to the first separator 121, and the other side is connected to the second separator 122. Therefore, the two side surfaces of the first pole piece 110 need to be sprayed with the normal-temperature and normal-pressure conductive adhesive, and two first glue spraying mechanisms 200 are provided to facilitate the glue spraying operation.

[0057] In some embodiments, referring to FIG. 7, two second glue spraying mechanisms 600 are provided, and the two second glue spraying mechanisms 600 are respectively configured to spray the normal-temperature and normal-pressure conductive adhesive to one side surface of the second pole piece 130 on the two sides of the separator 120. For example, one second glue spraying mechanism 600 is provided on one side of the first pole piece 110, and the other second glue spraying mechanism 600 is provided on the other side of the first pole piece 110. One second glue spraying mechanism 600 is configured to spray the normal-temperature and normal-pressure conductive adhesive to the surface of the second pole piece 130 on the side of the first separator 121.

[0058] In other embodiments, one first glue spraying mechanism 200 and one second glue spraying mechanism 600 are provided. The first glue spraying mechanism 200 is configured to spray the normal-temperature and normal-pressure conductive adhesive to the side surface of the first pole piece 110 connected to the separator 120. The second glue spraying mechanism 600 is configured to spray the normal-temperature and normal-pressure conductive adhesive to the side surface of the second pole piece 130 connected to the separator 120.

[0059] For example, one separator 120 is provided, and the first pole piece 110 is connected to one side of the separator 120 by the normal-temperature and normal-pressure conductive adhesive, and the second pole piece 130 is connected to the other side of the separator 120 by the normal-temperature and normal-pressure conductive adhesive. The first pole piece 110 and the second pole piece 130 are alternately arranged along the length direction of the separator 120.

[0060] In some embodiments, the spraying area of the normal temperature and pressure conductive adhesive on the first tab 110 is S1, wherein 0.8A1≤S1≤A1, A1 is the area of one side surface of the first tab 110. The value of S1 can be 0.8A1, 0.9A1, A1 or other values not listed.

[0061] In the embodiments of the present application, the glue spraying area of the first tab 110 accounts for 80% or more of one side surface of the first tab 110. The glue spraying area is large, the first tab 110 is stably bonded with the separator 120, and the conductivity of the normal temperature and pressure conductive adhesive is not affected.

[0062] In some embodiments, the spraying area of the normal temperature and pressure conductive adhesive on the second tab 130 is S2, wherein 0.8A2≤S2≤A2, A2 is the area of one side surface of the second tab 130. The value of S2 can be 0.8A2, 0.9A2, A2 or other values not listed.

[0063] In some embodiments of the present application, the glue spraying area of the second tab 130 accounts for 80% or more of one side surface of the second tab 130. The glue spraying area is large, the second tab 130 is stably bonded with the separator 120, and the conductivity of the normal temperature and pressure conductive adhesive is not affected.

[0064] In some embodiments, the spraying thickness of the normal temperature and pressure conductive adhesive on the first tab 110 is D1, wherein 1μm≤D1≤2μm. The value of D1 can be 1μm, 1.2μm, 1.5μm, 1.7μm, 1.8μm, 1.9μm, 2μm or other values not listed.

[0065] In some embodiments, the spraying thickness of the normal temperature and pressure conductive adhesive on the second tab 130 is D2, wherein 1μm≤D2≤2μm. The value of D2 can be 1μm, 1.2μm, 1.5μm, 1.7μm, 1.8μm, 1.9μm, 2μm or other values not listed. The value of D2 can be the same as or different from the value of D1.

[0066] The spraying thickness of the normal temperature and pressure conductive adhesive on the first tab 110 and the second tab 130 is moderate, which meets the performance requirements of bonding and conductivity, and reduces the probability of overflow of the normal temperature and pressure conductive adhesive after passing through the pressure roller due to excessive spraying of the normal temperature and pressure conductive adhesive.

[0067] The embodiments of the present application also provide a preparation method of a jelly-roll battery cell, comprising the following steps:

[0068] S1, preparing the first tab 110 and the second tab 130;

[0069] S2, spraying the normal temperature and pressure conductive adhesive on the two side surfaces of the first pole piece 110, and connecting the first pole piece 110 and the two layers of the separator 120, spraying the normal temperature and pressure conductive adhesive on one side surface of the second pole piece 130, and connecting the second pole piece 130 and the side of the separator 120 away from the first pole piece 110, to prepare the battery cell structure;

[0070] S3, folding the battery cell structure to prepare the jelly-roll battery cell.

[0071] In the embodiments of the present application, the first pole piece 110 and the second pole piece 130 can be prepared simultaneously or separately, as long as the preparation of the first pole piece 110 and the second pole piece 130 is completed before the first pole piece 110 and the second pole piece 130 are attached to the separator 120.

[0072] In some embodiments, the normal temperature and pressure conductive adhesive is PVDF-HFP.

Claims

1. A jelly-roll battery cell (10), the jelly-roll battery cell being prepared by folding a battery cell structure, the battery cell structure comprising: a first electrode sheet (110) ; a separator (120), the first electrode sheet (110) being disposed on one side of the separator (120), the first electrode sheet (110) and the separator (120) being connected by a normal-temperature and normal-pressure conductive adhesive; a second electrode sheet (130), the second electrode sheet (130) being disposed on the side of the separator (120) away from the first electrode sheet (110), the second electrode sheet (130) and the separator (120) being connected by the normal-temperature and normal-pressure conductive adhesive.

2. The stacked cell (10) of claim 1, wherein, Two separators (120) are provided, which are a first separator (121) and a second separator (122), the first electrode sheet (110) being located between the first separator (121) and the second separator (122), the two sides of the first electrode sheet (110) being connected to the first separator (121) and the second separator (122), respectively, by the normal-temperature and normal-pressure conductive adhesive, the second electrode sheet (130) being disposed on the side of the first separator (121) away from the first electrode sheet (110) and on the side of the second separator (122) away from the first electrode sheet (110), a plurality of the second electrode sheets (130) being alternately disposed on the first separator (121) and the second separator (122) along the length direction of the separator (120).

3. The stacked cell (10) of claim 2, wherein, The first electrode sheet (110) is a negative electrode sheet, and the second electrode sheet (130) is a positive electrode sheet.

4. The stacked cell (10) of claim 3, wherein, The negative electrode sheet is a continuous electrode sheet, and the negative electrode sheet corresponds to a plurality of the positive electrode sheets.

5. The stacked cell (10) of claim 1, wherein, One separator (120) is provided, the first electrode sheet (110) and the second electrode sheet (130) being alternately and spacedly disposed on the two sides of the separator (120), the first electrode sheet (110) being located on one side of the separator (120), one side surface of the first electrode sheet (110) being connected to one side surface of the separator (120) by the normal-temperature and normal-pressure conductive adhesive, the second electrode sheet (130) being located on the other side of the separator (120), one side surface of the second electrode sheet (130) being connected to the other side surface of the separator (120) by the normal-temperature and normal-pressure conductive adhesive.

6. The stacked cell (10) according to any one of claims 1 to 5, wherein The normal-temperature and normal-pressure conductive adhesive comprises PVDF-HFP.

7. The stacked cell (10) according to any one of claims 1 to 6, wherein A first tab is provided on the first electrode sheet (110), the first tab extending out of the separator (120).

8. The stacked cell (10) according to any one of claims 1 to 7, wherein A second tab is provided on the second electrode sheet (130), the second tab extending out of the separator (120). 9.A jelly-roll battery cell preparation device, comprising: a first electrode sheet preparation unit (100) configured to prepare a first electrode sheet (110) ; a first adhesive spraying mechanism (200) disposed downstream of the first electrode sheet preparation unit (100) and configured to spray a normal-temperature and normal-pressure conductive adhesive onto the surface of the first electrode sheet (110) ; a separator unwinding mechanism (300) disposed downstream of the first adhesive spraying mechanism (200) and configured to deliver a separator (120) ; A first composite mechanism (400) is arranged downstream of the diaphragm unwinding mechanism (300) and includes two first pressure rollers (410) arranged oppositely. After the first pole piece (110) and the diaphragm (120) pass through the first pressure rollers (410), a first composite belt is prepared. The pressure applied by the first pressure rollers (410) is P1, where 0.05T≤P1≤0.1T. A second pole piece preparation unit (500) is arranged downstream of the first composite mechanism (400) and is configured to prepare a second pole piece (130). A second glue spraying mechanism (600) is arranged downstream of the second pole piece preparation unit (500) and is configured to spray the normal-temperature and normal-pressure conductive adhesive on the surface of the second pole piece (130) connected to the first composite belt. A second composite mechanism (700) is arranged downstream of the second glue spraying mechanism (600) and includes two second pressure rollers (710) arranged oppositely. After the first composite belt and the second pole piece (130) pass through the second pressure rollers (710), an electric cell structure is prepared. The pressure applied by the second pressure rollers (710) is P2, where 0.05T≤P2≤0.1T. A folding mechanism (800) is arranged to fold the electric cell structure to prepare a laminated cell (10).

10. The production apparatus for the stacked cell according to claim 9, wherein Two first glue spraying mechanisms (200) are arranged to spray the normal-temperature and normal-pressure conductive adhesive on the two side surfaces of the first pole piece (110), respectively.

11. The production apparatus for the stacked cell according to claim 9 or 10, wherein Two second glue spraying mechanisms (600) are arranged to spray the normal-temperature and normal-pressure conductive adhesive on one side surface of the second pole piece (130) on both sides of the diaphragm (120), respectively.

12. The production apparatus of the stacked cell according to any one of claims 9 to 11, wherein The spraying area of the normal-temperature and normal-pressure conductive adhesive on the first pole piece (110) is S1, where 0.8A1≤S1≤A1, and A1 is the area of one side surface of the first pole piece (110). Alternatively, the spraying area of the normal-temperature and normal-pressure conductive adhesive on the second pole piece (130) is S2, where 0.8A2≤S2≤A2, and A2 is the area of one side surface of the second pole piece (130).

13. The production apparatus for the stacked cells according to any one of claims 9 to 12, wherein The spraying thickness of the normal-temperature and normal-pressure conductive adhesive on the first pole piece (110) is D1, where 1μm≤D1≤2μm.

14. The production apparatus for the stacked cells according to any one of claims 9 to 13, wherein The spraying thickness of the normal-temperature and normal-pressure conductive adhesive on the second pole piece (130) is D2, where 1μm≤D2≤2μm.

15. The production apparatus for the stacked cells according to any one of claims 9 to 14, wherein The normal-temperature and normal-pressure conductive adhesive includes PVDF-HFP.

16. A method for preparing a laminated cell, comprising the following steps: preparing a first pole piece (110) and a second pole piece (130); Spray a normal temperature and pressure conductive adhesive on both side surfaces of a first pole piece (110), and composite connect the first pole piece (110) with two layers of diaphragms (120); spray the normal temperature and pressure conductive adhesive on one side surface of a second pole piece (130), and composite connect the second pole piece (130) with the diaphragm (120) away from the first pole piece (110), to prepare a battery cell structure; Fold the battery cell structure to prepare a laminated battery cell (10).

17. The method of manufacturing a stacked cell of claim 16, wherein, The normal temperature and pressure conductive adhesive comprises PVDF-HFP.

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