Blade battery and battery pack having same

Abstract

Disclosed are a blade battery and a battery pack having same. The blade battery comprises at least one positive electrode sheet, a plurality of negative electrode sheets, a positive electrode cover plate and a negative electrode cover plate. A first tab and a second tab are respectively provided on two adjacent edges of the positive electrode sheet. The plurality of negative electrode sheets respectively cover two opposite sides of the positive electrode sheet, a third tab and a fourth tab are respectively provided on two adjacent edges of each negative electrode sheet, the positive electrode sheet and the negative electrode sheets are stacked, with the edges thereof flush with each other, the first tab and the third tabs are respectively located on two opposite sides of the blade battery, and the second tab and the fourth tabs are respectively located on two opposite sides of the blade battery. The positive electrode cover plate is located on two adjacent edges of the blade battery, and the positive electrode cover plate is connected to the first tab and the second tab to form a positive electrode. The negative electrode cover plate is located on two adjacent edges of the blade battery, and the negative electrode cover plate is connected to the third tabs and the fourth tabs to form a negative electrode.

Description

Blade battery and battery pack with same

[0001] Cross-reference to Related Applications

[0002] The present application claims priority to the Chinese patent application No. 202411223558.6, filed on September 3, 2024, entitled “Blade battery and battery pack with same”, the whole content of which is incorporated herein by reference. TECHNICAL FIELD

[0003] The present disclosure relates to the technical field of battery, in particular to a blade battery and a battery pack with same. BACKGROUND

[0004] With the rapid development of new energy technology, lithium ion batteries are increasingly popular in people's life and work. In order to reduce costs, the main method at present is to improve the capacity and energy of single cell, so as to reduce the manufacturing cost and material cost. However, due to the problems of winding technology and internal tension unevenness, the winding square can cell with high production efficiency cannot achieve super large size and super large capacity. Therefore, the large size square can blade battery becomes an important direction for people to develop the next generation of lithium ion cells.

[0005] With the gradual increase of the capacity of single cell in the related art blade battery, the length of the blade battery will also increase. During the charging and discharging process, the positive and negative cover plates on both sides need to conduct electrons from one side of the pole cover plate to the other side of the pole cover plate along the length direction, and the transmission distance is long, which leads to the increase of the internal resistance of the cell, and the polarization is obviously poor. The increase of internal resistance not only leads to the increase of heat production of the cell, but also increases the working environment temperature, and the internal side reaction of the cell is severe, which reduces the cycle life. Moreover, the heat production of the cell is large, which means that the energy loss during the charging and discharging process is large. Moreover, the large polarization of the cell also affects the virtual charging condition caused by the charging of the lithium battery, and the internal power of the cell cannot be fully discharged in the high-power and low-temperature environment, which seriously affects the user experience.

[0006] SUMMARY

[0007] The present disclosure aims to at least solve one of the technical problems existing in the prior art. To this end, one object of the present disclosure is to provide a blade battery, which has the advantages of high charging and discharging energy efficiency, low internal resistance, and small energy loss.

[0008] The present disclosure also provides a battery pack with the blade battery.

[0009] To achieve the above object, according to an embodiment of a first aspect of the present disclosure, a blade battery is provided, comprising: at least one positive electrode sheet, two adjacent edges of the positive electrode sheet being respectively provided with a first tab and a second tab; a plurality of negative electrode sheets, the plurality of negative electrode sheets respectively wrapping opposite sides of the positive electrode sheet, two adjacent edges of the negative electrode sheet being respectively provided with a third tab and a fourth tab, the positive electrode sheet and the negative electrode sheet being stacked and arranged with edges flush with each other, the first tab and the third tab being respectively located on opposite sides of the blade battery, and the second tab and the fourth tab being respectively located on opposite sides of the blade battery; a positive electrode cover plate, a conductive area of the positive electrode cover plate being located on two adjacent edges of the blade battery, the positive electrode cover plate being connected with the first tab and the second tab to form a positive electrode; and a negative electrode cover plate, a conductive area of the negative electrode cover plate being located on two adjacent edges of the blade battery, the negative electrode cover plate being connected with the third tab and the fourth tab to form a negative electrode.

[0010] The blade battery according to the embodiment of the present disclosure has the advantages of high charging and discharging energy efficiency, reduced internal resistance, and small energy loss.

[0011] According to some specific embodiments of the present disclosure, the first tab and the second tab are both configured as full tabs, and the first tab and the second tab respectively continuously extend along the corresponding side edges of the positive electrode sheet; the third tab and the fourth tab respectively continuously extend along the corresponding side edges of the negative electrode sheet; and / or the first tab, the second tab, the third tab, and the fourth tab are all configured as rectangles or trapezoids.

[0012] According to some specific embodiments of the present disclosure, the first tab and the second tab are connected to the positive electrode cover plate after being bent relative to the positive electrode sheet; and the third tab and the fourth tab are connected to the negative electrode cover plate after being bent relative to the negative electrode sheet.

[0013] According to some specific embodiments of the present disclosure, the positive electrode cover plate comprises a positive electrode end plate and a positive electrode conductive sheet, the positive electrode conductive sheet being connected to a side of the positive electrode end plate facing the positive electrode sheet, and the positive electrode conductive sheet being electrically connected with the first tab and the second tab respectively; and / or the negative electrode cover plate comprises a negative electrode end plate and a negative electrode conductive sheet, the negative electrode conductive sheet being connected to a side of the negative electrode end plate facing the negative electrode sheet, and the negative electrode conductive sheet being electrically connected with the third tab and the fourth tab respectively.

[0014] Further, the positive conductive sheet comprises: a first conductive part which is attached to the positive end plate and connected with the first tab; and a second conductive part which is connected to the first conductive part and vertically bent relative to the first conductive part, and the second conductive part is connected with the second tab; and / or, the negative conductive sheet comprises: a third conductive part which is attached to the negative end plate and connected with the third tab; and a fourth conductive part which is connected to the third conductive part and vertically bent relative to the third conductive part, and the fourth conductive part is connected with the fourth tab.

[0015] Further, the positive sheet and the negative sheet are both configured as a rectangle, the second conductive part continuously extends along the long side of the positive sheet, and the fourth conductive part continuously extends along the long side of the negative sheet.

[0016] According to some embodiments of the present disclosure, the positive cover plate further comprises a positive pole which penetrates through the positive end plate and is connected with the positive conductive sheet; and / or, the negative cover plate further comprises a negative pole which penetrates through the negative end plate and is connected with the negative conductive sheet.

[0017] According to some embodiments of the present disclosure, the blade battery further comprises: a packaging shell which has an opening exposing the positive end plate and the negative end plate on the end face of the blade battery, and the positive sheet and the negative sheet are both accommodated in the packaging shell.

[0018] According to some embodiments of the present disclosure, the positive conductive sheet is an aluminum sheet which is welded with the first tab and the second tab; and / or, the negative conductive sheet is a copper sheet which is welded with the third tab and the fourth tab.

[0019] According to some embodiments of the present disclosure, the blade battery is configured as a cuboid, and / or the length of the blade battery is 500mm-1350mm; and / or, the thickness of the blade battery is 25mm-40mm; and / or, the width of the blade battery is 200mm-319mm.

[0020] Further, the ratio of the length to the thickness of the blade battery is 12.5:1-40:1; and / or, the ratio of the length to the width of the blade battery is 1.57:1-6.75:1; and / or, the ratio of the width to the thickness of the blade battery is 5:1-13:1.

[0021] According to some embodiments of the present disclosure, the conductive agent of the positive sheet comprises conductive carbon black and carbon nanotubes; and / or, the conductive agent of the negative sheet comprises conductive carbon black.

[0022] Further, the mass ratio of the conductive carbon black of the conductive agent of the positive electrode sheet is 0.5% to 1.0%, and the mass ratio of the carbon nanotube of the positive electrode sheet is 0.5% to 1.0%; the mass ratio of the conductive carbon black of the conductive agent of the negative electrode sheet is 0.5% to 1.0%.

[0023] According to some embodiments of the present disclosure, the thickness of the first tab, the second tab, the third tab, and the fourth tab ranges from 1 μm to 20 μm.

[0024] According to embodiments of the second aspect of the present disclosure, a battery pack is provided, comprising: a battery box; and a plurality of blade batteries according to the above embodiments of the present disclosure, the plurality of blade batteries being arranged along the thickness direction thereof and mounted in the battery box.

[0025] According to the battery pack of the embodiments of the present disclosure, by using the blade battery according to the above embodiments of the present disclosure, the battery pack has the advantages of high charge-discharge energy efficiency, low internal resistance, and small energy loss.

[0026] Additional aspects and advantages of the present disclosure will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0027] The above and / or additional aspects and advantages of the present disclosure will become apparent and be readily appreciated from the following description, including the appended drawings.

[0028] FIG. 1 is a structural schematic diagram of a blade battery of the prior art;

[0029] FIG. 2 is a structural schematic diagram of a blade battery according to embodiments of the present disclosure;

[0030] FIG. 3 is a schematic diagram of a positive electrode sheet of a blade battery according to embodiments of the present disclosure;

[0031] FIG. 4 is a schematic diagram of a negative electrode sheet of a blade battery according to embodiments of the present disclosure;

[0032] FIG. 5 is a schematic diagram of a positive electrode sheet and a negative electrode sheet of a blade battery according to embodiments of the present disclosure;

[0033] FIG. 6 is a schematic diagram of a positive electrode cover plate of a blade battery according to embodiments of the present disclosure;

[0034] FIG. 7 is a schematic diagram of a negative electrode cover plate of a blade battery according to embodiments of the present disclosure;

[0035] FIG. 8 is a structural schematic diagram of the inside of a blade battery according to embodiments of the present disclosure;

[0036] FIG. 9 is an assembly schematic view of a blade battery according to an embodiment of the present disclosure;

[0037] FIG. 10 is a schematic block diagram of a battery pack according to an embodiment of the present disclosure.

[0038] Reference signs: blade battery 1', positive cover plate 300', negative cover plate 400'; battery pack 1000; battery box 2; blade battery 1, positive plate 100, first tab 101, second tab 102, negative plate 200, third tab 201, fourth tab 202, positive cover plate 300, negative cover plate 400, packaging shell 500, separator 600, positive end plate 310, positive conductive sheet 320, negative end plate 410, negative conductive sheet 420, first conductive part 321, second conductive part 322, third conductive part 421, fourth conductive part 422, positive pole 330, negative pole 430, explosion-proof valve 340, liquid injection hole 350, opening 501. DETAILED DESCRIPTION

[0039] In the description of the present disclosure, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present disclosure.

[0040] In the description of the present disclosure, "first feature" and "second feature" can include one or more of the features.

[0041] In the description of the present disclosure, the meaning of "a plurality of" is two or more.

[0042] In the description of the present disclosure, the "above" or "below" of the first feature to the second feature can include that the first and second features are in direct contact, or can include that the first and second features are not in direct contact but are in contact through another feature therebetween.

[0043] In the description of the present disclosure, the "above", "over" and "on" of the first feature to the second feature include that the first feature is directly above and obliquely above the second feature, or only means that the first feature is higher than the second feature in horizontal height.

[0044] As shown in FIG. 1, the blade battery 1' generally adopts the structure of oppositely arranged positive cover plate 300' and negative cover plate 400'. In the charging and discharging process, electrons need to conduct between the positive cover plate 300' on one side and the negative cover plate 400' on the other side along the length direction of the blade battery 1', but the transmission distance is long and the internal resistance is large. To solve the above problems, the present disclosure provides a new type of blade battery 1.

[0045] The blade battery 1 according to the embodiment of the present disclosure is described below with reference to the accompanying drawings.

[0046] As shown in FIGS. 2-10, the blade battery 1 according to the embodiment of the present disclosure comprises at least one positive sheet 100, a plurality of negative sheets 200, a positive cover plate 300 and a negative cover plate 400. As shown in FIG. 3, the adjacent two edges of the positive sheet 100 are respectively provided with a first tab 101 and a second tab 102. The plurality of negative sheets 200 respectively cover the opposite two sides of the positive sheet 100. As shown in FIG. 4, the adjacent two edges of the negative sheet 200 are respectively provided with a third tab 201 and a fourth tab 202. The positive sheet 100 and the negative sheet 200 are stacked and arranged with edges flush with each other. The first tab 101 and the third tab 201 are respectively located on the opposite two sides of the blade battery 1, and the second tab 102 and the fourth tab 202 are respectively located on the opposite two sides of the blade battery 1. The conductive area of the positive cover plate 300 is located on the adjacent two edges of the blade battery 1. The conductive area of the positive cover plate 300, such as the positive conductive sheet 320, is connected with the first tab 101 and the second tab 102 to form a positive electrode. The conductive area of the negative cover plate 400, such as the negative conductive sheet 420, is located on the adjacent two edges of the blade battery 1. The negative cover plate 400 is connected with the third tab 201 and the fourth tab 202 to form a negative electrode.

[0047] It should be noted that the adjacent two edges of the blade battery 1 refer to the side edges parallel to the plane of the positive sheet 100 and the negative sheet 200, i.e. the side edges of the plane where the length and width of the blade battery 1 are located. The conductive area of the positive cover plate 300 and the conductive area of the negative cover plate 400 are located on the side edges of the blade battery 1 and extend along the thickness direction of the blade battery 1 to cover all the positive sheets 100 and the negative sheets 200, so as to facilitate the connection of the conductive area of the positive cover plate 300 with the first tab 101 and the second tab 102, and the connection of the conductive area of the negative cover plate 400 with the third tab 201 and the fourth tab 202.

[0048] For example, the positive electrode sheet 100 and the negative electrode sheet 200 are both multiple, the shapes of the multiple positive electrode sheets 100 and the multiple negative electrode sheets 200 are the same and the outer contours of the multiple positive electrode sheets 100 and the multiple negative electrode sheets 200 coincide with each other. The positive electrode sheets 100 and the negative electrode sheets 200 are arranged in layers in sequence, and each layer of the positive electrode sheets 100 and the negative electrode sheets 200 is spaced apart by the separator 600, and finally full-sealing welding, liquid injection, formation, and capacity distribution are performed, so that a blade battery 1 with high charge-discharge energy efficiency is obtained. Among them, the first tab 101 and the second tab 102 are located in the middle of the edge where the positive electrode sheet 100 is located, and the third tab 201 and the fourth tab 202 are located in the middle of the edge where the negative electrode sheet 200 is located. The first tab 101 and the third tab 201 are symmetrically arranged on opposite edges of the blade battery 1, and the second tab 102 and the fourth tab 202 are symmetrically arranged on the other opposite edges of the blade battery 1, so that the electrons can conduct to the first tab 101 and the third tab 102 in the length direction, and can also conduct to the second tab 201 and the fourth tab 202 in the width direction.

[0049] According to the blade battery 1 of the embodiment of the present disclosure, the first tab 101 and the second tab 102 are arranged on two adjacent edges of the positive electrode sheet 100, and the third tab 201 and the fourth tab 202 are arranged on two adjacent edges of the negative electrode sheet 200. The electrons of the blade battery 1 flow between the first tab 101 and the third tab 201, and flow between the second tab 102 and the fourth tab 202, thereby forming two electron flow paths in the length direction and the width direction inside the blade battery 1. In the process of charging and discharging, the internal resistance of the battery cell composed of the positive electrode sheet 100 and the negative electrode sheet 200 is significantly reduced, thereby reducing the heat generated, reducing the energy loss, prolonging the service life of the blade battery 1, and improving the energy efficiency. Moreover, the electrons flow in different directions, which also improves the charge-discharge capacity. In the charging process of the blade battery 1, the internal charge of the battery cell formed by the positive electrode sheet 100 and the negative electrode sheet 200 is sufficient, which ensures sufficient power, and the power can also be fully discharged in the discharging process, improving the user experience.

[0050] Therefore, the blade battery 1 according to the embodiment of the present disclosure has the advantages of high charge-discharge energy efficiency, low internal resistance, and small energy loss.

[0051] In some embodiments of the present disclosure, the first and second tabs 101 and 102 are each configured as a full tab, and the first and second tabs 101 and 102 extend continuously along the corresponding side edges of the positive plate 100, respectively. The third and fourth tabs 201 and 202 extend continuously along the corresponding side edges of the negative plate 200, respectively. That is, the first, second, third, and fourth tabs 101, 102, 201, and 202 are each a continuous whole structure, which facilitates the connection of the first and second tabs 101 and 102 to the positive cover plate 300 and the connection of the third and fourth tabs 201 and 202 to the negative cover plate 400, and on the other hand, can increase the current conduction area of the first, second, third, and fourth tabs 101, 102, 201, and 202 and reduce the internal resistance of the blade battery 1.

[0052] The first tab 101 forms a full tab extending along an entire edge on one edge of the positive plate 100, and the second tab 102 forms a full tab extending along an entire edge on another edge of the positive plate 100. When the first and second tabs 101 and 102 are in conduction with the positive plate 100, the cross-sectional area of the current flow is large, thereby reducing the internal resistance. After the internal resistance is reduced, the voltage drop during large current charging and discharging is reduced, and the electrical energy can be more efficiently output and received. That is, the first and second tabs 101 and 102 correspond in position to the positive cover plate 300 and form an electrical connection, and the contact area of the first and second tabs 101 and 102 of the positive plate 100 with the positive cover plate 300 is large, and thus the conduction area of the electrons is large, improving the overcurrent capacity of the positive plate 100.

[0053] Similarly, the third tab 201 forms a full tab extending along an entire edge on one edge of the negative plate 200. The fourth tab 202 forms a full tab extending along an entire edge on another edge of the positive cover plate 300. When the third and fourth tabs 201 and 202 are in conduction with the negative plate 200, the cross-sectional area of the current flow is large, thereby reducing the internal resistance. After the internal resistance is reduced, the voltage drop during large current charging and discharging is reduced, and the electrical energy can be more efficiently output and received. That is, the third and fourth tabs 201 and 202 correspond in position to the positive cover plate 300 and form an electrical connection, and the contact area of the third and fourth tabs 201 and 202 of the negative plate 200 with the positive cover plate 400 is large, and thus the conduction area of the electrons is large, improving the overcurrent capacity of the positive plate 100.

[0054] In some embodiments of the present disclosure, the first tab 101 and the second tab 102 are connected to the positive cover plate 300 after being folded relative to the positive plate 100. The third tab 201 and the fourth tab 202 are connected to the negative cover plate 400 after being folded relative to the negative plate 200.

[0055] By configuring the tab shape to be rectangular or trapezoidal, electrons can be conducted in the first tab 101 of the full tab structure of the positive plate 100 and the second tab 102 of the full tab structure of the positive plate 100. Electrons can be conducted in the third tab 201 of the full tab structure of the negative plate 200 and the fourth tab 202 of the full tab structure of the negative plate 200, thereby improving the energy density of the blade battery 1.

[0056] In some embodiments of the present disclosure, the first tab 101 and the second tab 102 are connected to the positive cover plate 300 after being folded relative to the positive plate 100. The third tab 201 and the fourth tab 202 are connected to the negative cover plate 400 after being folded relative to the negative plate 200.

[0057] Specifically, the first tab 101 and the second tab 102 form a folding structure of about 90° relative to the positive plate 100, and the third tab 201 and the fourth tab 202 form a folding structure of about 90° relative to the negative plate 200, so that the first tab 101 and the second tab 102 are in contact with the surface of the positive cover plate 300, forming a surface-to-surface contact; the third tab 201 and the fourth tab 202 are in contact with the surface of the negative cover plate 400, forming a surface-to-surface contact, thereby facilitating the welding of the first tab 101 and the second tab 102 to the positive cover plate 300, and the welding of the third tab 201 and the fourth tab 202 to the negative cover plate 400, thereby maintaining electrical connection at all times and having high reliability.

[0058] In some embodiments of the present disclosure, as shown in FIG. 6, the positive cover plate 300 includes a positive end plate 310 and a positive conductive sheet 320, the positive conductive sheet 320 is connected to the side of the positive end plate 310 facing the positive plate 100, and the positive conductive sheet 320 is electrically connected to the first tab 101 and the second tab 102, respectively. The positive end plate 310 is used to seal the blade battery 1 at one end of the blade battery 1, and on the other hand, forms a carrier for the positive conductive sheet 320. The positive conductive sheet 320 is welded to the positive end plate 310 to achieve electrical connection, and the positive conductive sheet 320 is also connected to the first tab 101, the second tab 102, and the positive plate 100 for electrical conduction.

[0059] Likewise, as shown in FIG. 7, the negative cover plate 400 includes a negative terminal plate 410 and a negative conductive tab 420 connected to the side of the negative terminal plate 410 facing the negative tab 200, and the negative conductive tab 420 is electrically connected to the third and fourth tabs 201 and 202, respectively. The negative terminal plate 410 is used to seal the blade battery 1 at the other end of the blade battery 1 and forms a carrier for the negative conductive tab 420. The negative conductive tab 420 is welded to the negative terminal plate 410 to achieve electrical connection, and the negative conductive tab 420 is also connected to the third and fourth tabs 201 and 202 and the negative tab 200 for electrical conduction.

[0060] Further, as shown in FIG. 6, the positive conductive tab 320 includes a first conductive portion 321 and a second conductive portion 322. The first conductive portion 321 is attached to the positive terminal plate 310 and connected to the first tab 101. The second conductive portion 322 is connected to the first conductive portion 321 and bent perpendicularly relative to the first conductive portion 321, and the second conductive portion 322 is connected to the second tab 102. For example, the first conductive portion 321 and the second conductive portion 322 are formed by bending a single conductive tab. As shown in FIG. 7, the negative conductive tab 420 includes a third conductive portion 421 and a fourth conductive portion 422. The third conductive portion 421 is attached to the negative terminal plate 410 and connected to the third tab 201. The fourth conductive portion 422 is connected to the third conductive portion 421 and bent perpendicularly relative to the third conductive portion 421, and the fourth conductive portion 422 is connected to the fourth tab 202. For example, the third conductive portion 421 and the fourth conductive portion 422 are formed by bending a single conductive tab. Thus, the conductive structure of the positive conductive tab 320 and the negative conductive tab 420 not only occupies less space, but also has better electrical conductivity.

[0061] Further, the positive tab 100 and the negative tab 200 are both configured as long rectangles, the second conductive portion 322 extends continuously along the long side of the positive tab 100, and the fourth conductive portion 422 extends continuously along the long side of the negative tab 200.

[0062] In the drawings, the wavy lines in the middle of FIGS. 3 and 4 represent the omission of the break lines in the length direction of the positive tab 100 and the negative tab 200. By extending the second conductive portion 322 in the length direction of the positive tab 100 and the fourth conductive portion 422 in the length direction of the negative tab 200, a larger cross-sectional area for current flow is formed along one long side of the positive tab 100 and one long side of the negative tab 200, i.e., the entire long side of the blade battery 1 can form a current flow channel, greatly improving the current flow capacity of the blade battery 1.

[0063] In some embodiments of the present disclosure, as shown in FIGS. 6 and 7, the positive cover plate 300 further comprises a positive pole 330 which passes through the positive end plate 310 and is connected with the positive conductive sheet 320. Similarly, the negative cover plate 400 further comprises a negative pole 430 which passes through the negative end plate 410 and is connected with the negative conductive sheet 420.

[0064] By connecting the positive pole 330 with the positive conductive sheet 320 through the positive cover plate 300 and connecting the negative pole 430 with the negative conductive sheet 420 through the negative cover plate 400, the single blade battery 1 can be connected with other blade batteries 1 or external circuits while ensuring the integrity of the end face structure of the blade battery 1.

[0065] In some embodiments of the present disclosure, as shown in FIG. 9, the blade battery 1 further comprises a packaging shell 500 which has an opening 501 exposing the positive end plate 310 and the negative end plate 410 on the end face of the blade battery 1, and the positive sheet 100 and the negative sheet 200 are both accommodated in the packaging shell 500.

[0066] For example, the packaging shell 500 is configured as a frame-shaped structure with an opening on one side, and after the assembly of the positive sheet 100, the negative sheet 200, the positive cover plate 300 and the negative cover plate 400 is completed, the whole is loaded into the packaging shell 500 through the opening. After assembly, the positive cover plate 300 and the negative cover plate 400 correspond to the openings 501 on both sides of the packaging shell 500 respectively, and the opening of the packaging shell 500 is welded, and the openings 501 on both sides of the packaging shell 500 are welded with the positive cover plate 300 and the negative cover plate 400 respectively, so that the positive cover plate 300, the negative cover plate 400 and the packaging shell 500 form a complete sealing structure to accommodate the electrolyte, and the positive sheet 100 and the negative sheet 200 are protected.

[0067] In addition, as shown in FIG. 9, at least one of the positive end plate 310 and the negative end plate 410 is configured with a liquid injection hole 350, so as to realize the function of injecting liquid into the positive sheet 100 and the negative sheet 200 in the packaging shell 500. In addition, at least one of the positive end plate 310 and the negative end plate 410 is configured with an explosion-proof valve 340, which can relieve pressure through the explosion-proof valve 340 when the pressure in the packaging shell 500 is too large to prevent the blade battery 1 from exploding.

[0068] In some embodiments of the present disclosure, the positive conductive sheet 320 is an aluminum sheet which is welded with the first and second tabs 101 and 102. The negative conductive sheet 420 is a copper sheet which is welded with the third and fourth tabs 201 and 202, for example, by laser welding.

[0069] Specifically, the first and second tabs 101 and 102 can be laser welded with the positive conductive tab 320 of the aluminum sheet. The third and fourth tabs 201 and 202 can be laser welded with the negative conductive tab 420 of the copper sheet. Both copper and aluminum are materials that meet the current collector and have good welding performance.

[0070] In some embodiments of the present disclosure, as shown in FIG. 1, the blade battery 1 is configured as a cuboid, the length of the blade battery 1 is 500mm-1350mm; the thickness is 25mm-40mm; and the width is 200mm-319mm.

[0071] It can be understood that the size of the blade battery 1 here refers to the size of the blade battery 1 monomer, not the size of the entire battery pack. The length of the blade battery 1 is the size in the left-right direction in FIG. 1, the thickness is the size in the front-back direction in FIG. 1, and the width is the size in the up-down direction in FIG. 1.

[0072] In order to reduce the manufacturing cost of the positive sheet 100 and the negative sheet 200 of the blade battery 1 and save the material of the battery cell, the length, width and thickness of the blade battery 1 monomer in the embodiments of the present disclosure are all large, which ensures a large battery capacity, and the capacity reaches more than 500Ah. It can be understood that if the length, width and thickness of the blade battery 1 are too small, the battery capacity will be affected, and if the length and width are too large, the polarization effect will be affected. The thickness of the blade battery 1 monomer in the present disclosure is kept at 25mm-40mm, the length is kept at 500mm-1350mm, and the height is kept at 200mm-319mm. The blade battery 1 forms a thin sheet structure and a thin design. Within this size range, the length and width of the blade battery 1 are large, and the thickness is thin, which can effectively transfer the heat at the center of the battery cell to the outside and improve the overall uniformity of the battery cell temperature on the premise of ensuring the capacity and polarization effect of the battery cell.

[0073] Further, the length to thickness ratio of the blade battery 1 is 12.5:1-40:1, and / or the length to width ratio is 1.57:1-6.75:1, and / or the width to thickness ratio is 5:1-13:1. While the size of the blade battery 1 is limited, the proportions of length, width, and height are also optimized. By increasing the length to width to thickness ratio, the blade battery 1 forms a larger and thinner structure, which can more effectively solve the heat dissipation problem and reduce the internal side reaction of the battery cell. The blade battery 1 of the embodiment of the present disclosure utilizes the unique design of the first tab 101, the second tab 102, the third tab 201, and the fourth tab 202 to make the electrons of the blade battery 1 flow between the first tab 101 and the third tab 201, and between the second tab 102 and the fourth tab 202, thereby forming an electron flow path in two directions along the length and width directions inside the blade battery 1. The electron transmission path during the charging and discharging of the battery cell is shortened, and the fast charging, rate, and low temperature performance of the blade battery 1 are improved.

[0074] In some embodiments of the present disclosure, the conductive agent of the positive electrode sheet 100 includes conductive carbon black and carbon nanotubes; and the conductive agent of the negative electrode sheet 200 includes conductive carbon black.

[0075] Further, the mass percentage of the conductive carbon black of the conductive agent of the positive electrode sheet 100 is 0.5%-1.0%, and the mass percentage of the carbon nanotubes of the positive electrode sheet 100 is 0.5%-1.0%; and the mass percentage of the conductive carbon black of the conductive agent of the negative electrode sheet 200 is 0.5%-1.0%. Since the electrons of the positive electrode sheet 100 and the negative electrode sheet 200 flow in different directions, the electronic conduction capacity of the battery cell formed by the positive electrode sheet 100 and the negative electrode sheet 200 is stronger, the content of the conductive agent can be appropriately reduced to reduce the material cost of the conductive agent of the positive electrode sheet 100 and the negative electrode sheet 200, and the energy density of the battery cell can be improved by increasing the active material content of the positive electrode sheet 100 and the negative electrode sheet 200.

[0076] In some embodiments of the present disclosure, the thickness of the first tab 101, the second tab 102, the third tab 201, and the fourth tab 202 ranges from 1 μm to 20 μm.

[0077] The first tab 101, the second tab 102, the third tab 201 and the fourth tab 202 only have a very small thickness. When the plurality of positive electrode sheets 100 and the plurality of negative electrode sheets 200 are arranged in a stacked manner, the plurality of first tabs 101 are arranged in a stacked manner, the plurality of second tabs 102 are arranged in a stacked manner, the plurality of third tabs 201 are arranged in a stacked manner, and the plurality of fourth tabs 202 are arranged in a stacked manner. Then, the first tab 101 and the second tab 102 after being folded are welded with the positive electrode conductive sheet 320. In this process, the plurality of first tabs 101 and the plurality of second tabs 102 arranged in a stacked manner and folded are fused with the positive electrode conductive sheet 320 to form an integral whole. Similarly, the third tab 201 and the fourth tab 202 are welded with the negative electrode conductive sheet 420. In this process, the plurality of third tabs 201 and the plurality of fourth tabs 202 arranged in a stacked manner and folded are arranged and fused with the negative electrode conductive sheet 420 to form an integral whole, so that the tabs only occupy a small space, thereby ensuring the space utilization rate and energy density of the blade battery 1.

[0078] In the following, the use amount and effect of the conductive agent of the positive electrode sheet 100 and the negative electrode sheet 200 are described in detail by taking experiments as examples.

[0079] Examples 1 and 2 are blade batteries 1 according to the present disclosure.

[0080] In Example 1, the conductive agent of the positive electrode sheet is conductive carbon black with a mass ratio of 0.5% and carbon nanotubes with a mass ratio of 0.5%. The conductive agent of the negative electrode sheet is conductive carbon black with a mass ratio of 0.5%.

[0081] In Example 2, the conductive agent of the positive electrode sheet is conductive carbon black with a mass ratio of 1.0% and carbon nanotubes with a mass ratio of 1.0%. The conductive agent of the negative electrode sheet is conductive carbon black with a mass ratio of 1.0%.

[0082] Comparative Examples 1 and 2 are blade batteries 1' according to the prior art, i.e. blade batteries 1' in which the electrons can only be conducted in the length direction in the positive cover plate and the negative cover plate arranged on the two sides.

[0083] In Comparative Example 1, the conductive agent of the positive electrode sheet is conductive carbon black with a mass ratio of 0.5% and carbon nanotubes with a mass ratio of 0.5%. The conductive agent of the negative electrode sheet is conductive carbon black with a mass ratio of 0.5%.

[0084] In Comparative Example 2, the conductive agent of the positive electrode sheet is conductive carbon black with a mass ratio of 1.0% and carbon nanotubes with a mass ratio of 1.0%. The conductive agent of the negative electrode sheet is conductive carbon black with a mass ratio of 1.0%.

[0085] The length, width, and thickness dimensions of the blade cells of Example 1, Example 2, Comparative Example 1, and Comparative Example 2 are all the same, with a length of 654.0 mm, a width of 225.0 mm, and a thickness of 39.0 mm.

[0086] The AC resistance (ACR), DC resistance (DCR), charge-discharge energy efficiency at 0.5 times rated power (0.5P), discharge temperature rise, and discharge energy and discharge temperature rise at 1 times rated power (1.0P) of the cells of Comparative Example 1 and Comparative Example 2 were compared with those of Example 1 and Example 2.

[0087] As shown in Tables 1-5:

[0088] Table 1: AC resistance (ACR) and DC resistance (DCR) of the cells

[0089] As can be seen from Table 1, in the charge-discharge process of the blade cell 1 of Example 1 and Example 2, the electrons can conduct in both the length direction and the width direction of the electrode sheet. In contrast, the electrons of the blade cell 1' of the prior art of Comparative Example 1 and Comparative Example 2 can only conduct in the length direction. Therefore, as shown in Table 1, the blade cell 1 of Example 1 and Example 2 greatly reduces the AC resistance and DC resistance of the cells.

[0090] Table 2: Charge-discharge energy efficiency at 0.5P, discharge temperature rise, and discharge energy and discharge temperature rise at 1.0P

[0091] As can be seen from Table 2, the blade cell 1 of Example 1 and Example 2 has a high charge-discharge energy efficiency compared to the blade cell 1' of Comparative Example 1 and Comparative Example 2.

[0092] The blade cell 1 of Example 1 and Example 2 has a high charge-discharge energy efficiency, especially when charging at 1 times rated power (1.0P), which enables a higher energy to be charged, thereby ensuring the discharge energy of the cells, and the discharge energy advantage is more obvious when the discharge power increases. In addition, the blade cell 1 of Example 1 and Example 2 can reduce the polarization resistance and discharge temperature rise of the cells, thereby reducing the side reactions inside the cells and improving the cycle life. At the same time, it also enables the end user to spend less energy and less configuration to maintain the working environment temperature of the cells.

[0093] Table 3: Discharge energy at 0°C, -10°C, and -30°C at 0.5P

[0094] According to the analysis of Table 3, by comparing the blade battery 1 of Example 1 and Example 2 with the blade battery 1' of Comparative Example 1 and Comparative Example 2, the blade battery 1 of Example 1 and Example 2 has higher discharge energy than the comparative examples when discharging in a low temperature environment. When the discharge temperature is further reduced, the discharge energy advantage is more obvious.

[0095] Table 4 Cycle performance data at room temperature 0.5P constant power

[0096] According to the analysis of Table 4, by comparing the blade battery 1 of Example 1 and Example 2 with the blade battery 1' of Comparative Example 1 and Comparative Example 2, the blade battery 1 of Example 1 and Example 2 can maintain a higher capacity retention rate at 500 times, 1000 times and 2000 times of charging, by reducing the side reaction in the battery cell, improving the cycle life. And because the unit cost of the conductive agent is higher, reducing the amount of conductive agent used can reduce the material cost of the battery cell.

[0097] It can be seen that the blade battery 1 of the embodiment of the present disclosure selects the conductive agent of the positive plate 100 as 0.5% to 1.0% of the conductive carbon black and 0.5% to 1.0% of the carbon nanotube by mass, and the mass ratio of the conductive carbon black of the conductive agent of the negative plate 200 is 0.5% to 1.0%. Compared with the existing blade battery 1' of the same conductive agent, the charge and discharge performance and service life are obviously improved.

[0098] Table 5 0.5P discharge energy and volume energy density

[0099] According to the analysis of Table 5, by comparing the blade battery 1 of Example 1 and Example 2 with the blade battery 1' of Comparative Example 1 and Comparative Example 2, the capacity of the blade battery 1 of Example 1 and Example 2 is higher than that of the blade battery 1' of Comparative Example 1 and Comparative Example 2, and the battery has better endurance. And the volume energy density of the blade battery 1 of Example 1 and Example 2 is also higher than that of the blade battery 1' of Comparative Example 1 and Comparative Example 2.

[0100] The battery pack 1000 according to the embodiment of the present disclosure is described below.

[0101] The battery pack 1000 according to the embodiment of the present disclosure, as shown in FIG. 10, comprises a battery box 2; and a plurality of blade batteries 1 according to any one of the above embodiments of the present disclosure, the plurality of blade batteries 1 are arranged along the thickness direction thereof and mounted in the battery box 2. Among them, different blade batteries 1 are electrically connected to each other through the positive cover plate 300 and the negative cover plate 400, realizing greater electric quantity and higher energy density.

[0102] According to the battery pack 1000 of the embodiment of the present disclosure, by using the blade battery 1 according to the above-mentioned embodiment of the present disclosure, the advantages of high charge-discharge energy efficiency, reduced internal resistance, small energy loss, etc. are achieved.

[0103] Other configurations and operations of the blade battery 1 and the battery pack 1000 according to the embodiment of the present disclosure are known to those skilled in the art, and will not be described in detail here.

[0104] In the description of the present specification, the description referring to the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present disclosure. In the present specification, the exemplary description of the above-mentioned terms does not necessarily mean the same embodiment or example.

[0105] Although the embodiments of the present disclosure have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made thereto without departing from the principles and spirit of the present disclosure, and the scope of the present disclosure is defined by the claims and their equivalents.

Claims

1. A blade battery (1) characterized in that, The application relates to a blade battery (1), comprising: at least one positive electrode sheet (100), two adjacent edges of the positive electrode sheet (100) are respectively provided with a first tab (101) and a second tab (102); a plurality of negative electrode sheets (200), the plurality of negative electrode sheets (200) respectively cover opposite sides of the positive electrode sheet (100), two adjacent edges of the negative electrode sheet (200) are respectively provided with a third tab (201) and a fourth tab (202), the positive electrode sheet (100) and the negative electrode sheet (200) are arranged in a stack and edges of the positive electrode sheet (100) and the negative electrode sheet (200) are flush with each other, the first tab (101) and the third tab (201) are respectively located on opposite sides of the blade battery (1), and the second tab (102) and the fourth tab (202) are respectively located on opposite sides of the blade battery (1); a positive electrode cover plate (300), a conductive area of the positive electrode cover plate (300) is located on two adjacent edges of the blade battery (1), and the positive electrode cover plate (300) is connected with the first tab (101) and the second tab (102) to form a positive electrode; and a negative electrode cover plate (400), a conductive area of the negative electrode cover plate (400) is located on two adjacent edges of the blade battery (1), and the negative electrode cover plate (400) is connected with the third tab (201) and the fourth tab (202) to form a negative electrode.

2. The blade battery (1) according to claim 1, wherein the first tab (101) and the second tab (102) are both configured as full tabs, the first tab (101) and the second tab (102) respectively continuously extend along corresponding side edges of the positive electrode sheet (100), the third tab (201) and the fourth tab (202) respectively continuously extend along corresponding side edges of the negative electrode sheet (200), and / or the first tab (101), the second tab (102), the third tab (201) and the fourth tab (202) are all configured as rectangles or trapezoids.

3. The blade battery (1) according to claim 1 or 2, wherein the first tab (101) and the second tab (102) are connected to the positive electrode cover plate (300) after being bent relative to the positive electrode sheet (100), the third tab (201) and the fourth tab (202) are connected to the negative electrode cover plate (400) after being bent relative to the negative electrode sheet (200).

4. The blade battery (1) according to any one of claims 1-3, wherein the positive electrode cover plate (300) comprises a positive electrode end plate (310) and a positive electrode conductive sheet (320), the positive electrode conductive sheet (320) is connected to a side of the positive electrode end plate (310) facing the positive electrode sheet (100), and the positive electrode conductive sheet (320) is electrically connected with the first tab (101) and the second tab (102) respectively, and / or the negative electrode cover plate (400) comprises a negative electrode end plate (410) and a negative electrode conductive sheet (420), the negative electrode conductive sheet (420) is connected to a side of the negative electrode end plate (410) facing the negative electrode sheet (200), and the negative electrode conductive sheet (420) is electrically connected with the third tab (201) and the fourth tab (202) respectively. The negative cover plate (400) comprises: a negative end plate (410) and a negative conductive sheet (420) connected to the side of the negative end plate (410) facing the negative sheet (200), and the negative conductive sheet (420) is electrically connected to the third tab (201) and the fourth tab (202) respectively.

5. The blade cell (1) according to claim 4, characterized in that, The positive conductive sheet (320) comprises: a first conductive part (321) attached to the positive end plate (310) and connected to the first tab (101); and a second conductive part (322) connected to the first conductive part (321) and vertically bent opposite to the first conductive part (321), and the second conductive part (322) is connected to the second tab (102); and / or, The negative conductive sheet (420) comprises: a third conductive part (421) attached to the negative end plate (410) and connected to the third tab (201); and a fourth conductive part (422) connected to the third conductive part (421) and vertically bent opposite to the third conductive part (421), and the fourth conductive part (422) is connected to the fourth tab (202).

6. The bladed battery (1) of claim 5, characterized in that The positive sheet (100) and the negative sheet (200) are both configured in a rectangular shape, the second conductive part (322) continuously extends along the long side of the positive sheet (100), and the fourth conductive part (422) continuously extends along the long side of the negative sheet (200).

7. The bladed battery (1) according to any one of claims 4-6, characterized in that, The positive cover plate (300) further comprises a positive pole (330) penetrating through the positive end plate (310) and connected to the positive conductive sheet (320); and / or, The negative cover plate (400) further comprises a negative pole (430) penetrating through the negative end plate (410) and connected to the negative conductive sheet (420).

8. The bladed battery (1) according to any one of claims 4-7, characterized in that, Further comprising: an encapsulation shell (500) having an opening (501) exposing the positive end plate (310) and the negative end plate (410) on the end face of the blade cell (1), and the positive sheet (100) and the negative sheet (200) are both accommodated in the encapsulation shell (500).

9. The bladed battery (1) according to any one of claims 4-8, characterized in that, The positive conductive sheet (320) is an aluminum sheet, and the positive conductive sheet (320) is welded to the first tab (101) and the second tab (102); and / or, The negative conductive sheet (420) is a copper sheet, and the negative conductive sheet (420) is welded to the third tab (201) and the fourth tab (202).

10. The bladed battery (1) according to any one of claims 1-9, characterized in that, The blade cell (1) is configured in a rectangular cuboid, and / or, The length of the blade cell (1) is 500mm-1350mm; and / or, The thickness of the blade cell (1) is 25mm-40mm; and / or, The width of the blade battery (1) is 200mm-319mm.

11. The bladed battery (1) according to any one of claims 1-10, characterized in that, The length to thickness ratio of the blade battery (1) is 12.5:1-40:1; and / or, The length to width ratio of the blade battery (1) is 1.57:1-6.75:1; and / or, The width to thickness ratio of the blade battery (1) is 5:1-13:

1.

12. The bladed battery (1) according to any one of claims 1-11, characterized in that, The conductive agent of the positive electrode sheet (100) comprises conductive carbon black and carbon nanotubes; and / or, the conductive agent of the negative electrode sheet (200) comprises conductive carbon black.

13. The bladed battery (1) according to claim 12, characterized in that The mass percentage of the conductive carbon black in the conductive agent of the positive electrode sheet (100) is 0.5%-1.0%, and the mass percentage of the carbon nanotubes in the positive electrode sheet (100) is 0.5%-1.0%; the mass percentage of the conductive carbon black in the conductive agent of the negative electrode sheet (200) is 0.5%-1.0%.

14. The bladed battery (1) according to any one of claims 1-13, characterized in that, The thickness of the first tab (101), the second tab (102), the third tab (201), and the fourth tab (202) ranges from 1μm to 20μm.

15. A battery pack (1000), characterized by, It comprises: a battery box (2); and a plurality of blade batteries (1) according to any one of claims 1-14, wherein the plurality of blade batteries (1) are arranged along the thickness direction thereof and installed in the battery box (2).

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