Laser sintering module and battery piece laser sintering equipment and method

Abstract

The invention relates to the technical field of photovoltaic battery piece manufacturing, and particularly discloses a laser sintering module and a battery piece laser sintering device and method. The laser sintering module comprises a power-up roll shaft assembly and a laser assembly; the power-up roll shaft assembly comprises an upper roll shaft and a lower roll shaft which are oppositely arranged in the vertical direction, each of the upper roll shaft and the lower roll shaft comprises a rotating shaft and a contact ring which sleeves the rotating shaft and is used for being in contact with a battery piece, the contact ring on the upper roll shaft is a first contact ring, and the contact ring on the lower roll shaft is a second contact ring; the laser sintering module further comprises a power source, at least one of all the first contact rings is electrically connected with one of the positive electrode and the negative electrode of the power source, and at least one of all the second contact rings is electrically connected with the other one of the positive electrode and the negative electrode of the power source. According to the device, the battery piece can be conveyed while voltage is applied to the battery piece, laser emitted by the laser assemblies can complete scanning of the whole battery piece, only one laser assembly is needed in the whole process, and the manufacturing cost of the device is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic cell manufacturing, and in particular to a laser sintering module, a cell laser sintering device and a method. Background Art

[0002] When a reverse voltage is applied to the cell, laser scanning of the gate line of the cell can significantly reduce the contact resistance between the gate line electrode and the silicon wafer, thereby improving the conversion efficiency of the cell.

[0003] In the current laser sintering module, when the cell is laser scanned, the cell is in a stationary state, and a reverse voltage is applied to the cell through a probe. Due to the obstruction of the probe, the laser component cannot completely scan the front surface of the cell at one time, and two sets of laser components are required, each set of laser components scans half of the cell, in order to achieve the purpose of completely scanning the front surface of the cell. In this way, the increase in the number of laser components leads to an increase in equipment costs, and the equipment structure is also more complicated. Summary of the invention

[0004] The object of the present invention is to provide a laser sintering module, a cell laser sintering device and a method that can transfer a cell while applying voltage to the cell.

[0005] To achieve the above object, the present invention provides a laser sintering module, comprising at least two groups of powered roller assemblies arranged along the front-to-back direction, and a laser assembly for emitting laser between the two groups of powered roller assemblies;

[0006] The power-on roller assembly comprises an upper roller and a lower roller which are arranged opposite to each other in the up-down direction, wherein the upper roller and the lower roller each comprise a rotating shaft and a contact ring which is sleeved on the rotating shaft and is used to contact the battery sheet, and each upper roller and each lower roller is provided with only one contact ring, the contact ring on the upper roller is a first contact ring, and the contact ring on the lower roller is a second contact ring;

[0007] The laser sintering module also includes a power supply, at least one of all the first contact rings is electrically connected to one of the positive and negative electrodes of the power supply, and at least one of all the second contact rings is electrically connected to the other of the positive and negative electrodes of the power supply.

[0008] As a further improvement of the present invention, all first contact rings are used to electrically connect one of the positive and negative poles of a power source, and all second contact rings are used to electrically connect the other of the positive and negative poles of a power source. The laser sintering module also includes a plurality of switching elements, and the switching elements are arranged between at least one of the first and second contact rings that are opposite to each other up and down and the power source.

[0009] As a further improvement of the present invention, the laser sintering module also includes a sensing element, which is arranged between the first group of powered roller assemblies and the second group of powered roller assemblies from back to front, so as to determine whether there are battery cells between the first group of powered roller assemblies and the second group of powered roller assemblies.

[0010] As a further improvement of the present invention, the lengths of the first contact ring and the second contact ring opposite to each other are different, wherein the upper roller shaft or the lower roller shaft where the shorter contact ring is located is provided with two insulating sleeves respectively located on both sides of the contact ring;

[0011] Among the upper roller and the lower roller, the one with a longer contact ring is the first roller, and the one with a shorter contact ring is the second roller. Among all the upper rollers, at least one is the first roller, and among all the lower rollers, at least one is the first roller.

[0012] As a further improvement of the present invention, the length of the shorter contact ring plus the length of the two insulating sleeves is equal to the length of the longer contact ring.

[0013] As a further improvement of the present invention, the powered roller shaft assembly is provided with four groups along the front-to-back direction and is evenly arranged, among the four upper roller shafts from the back to the front, the first upper roller shaft and the fourth upper roller shaft are the second roller shafts, the second upper roller shaft and the third upper roller shaft are the first roller shafts, and among the four lower roller shafts from the back to the front, the first lower roller shaft and the fourth lower roller shaft are the first roller shafts, and the second lower roller shaft and the third lower roller shaft are the second roller shafts;

[0014] The laser assembly is used for emitting laser light between the second upper roller and the third upper roller.

[0015] As a further improvement of the present invention, only one of the first contact ring and the second contact ring that are opposite to each other up and down is electrically connected to the positive electrode or the negative electrode of the power source.

[0016] As a further improvement of the present invention, the power-on roller shaft assembly is provided with four groups along the front-to-back direction and is evenly arranged, and among the four first contact rings and the four second contact rings from the back to the front, the second first contact ring and the third first contact ring are electrically connected to one of the positive and negative electrodes of the power supply, and the first second contact ring and the fourth second contact ring are electrically connected to the other of the positive and negative electrodes of the power supply;

[0017] The laser assembly is used for emitting laser light between the second upper roller and the third upper roller.

[0018] As a further improvement of the present invention, the rotating shaft includes a main shaft, an insulating layer sleeved on the main shaft, and a conductive layer sleeved on the insulating layer, the contact ring is sleeved on the conductive layer, at least one of the conductive layers of all the upper rollers is electrically connected to one of the positive and negative poles of the power supply, and at least one of the conductive layers of all the lower rollers is electrically connected to the other of the positive and negative poles of the power supply.

[0019] The present invention also provides a cell laser sintering device, which includes the above-mentioned laser sintering module.

[0020] The present invention also provides a cell laser sintering method, which uses the above cell laser sintering equipment and includes the following steps:

[0021] Applying voltage to the battery cell and conveying the battery cell from back to front in a front-to-back direction;

[0022] emitting a laser toward the battery cell, wherein when the laser is emitted, a dot-shaped light spot is formed on the plane where the battery cell is located;

[0023] Moving the laser so that the light spot performs multiple cycles of scanning along a preset scanning path;

[0024] Assuming that in a transverse direction perpendicular to the front-rear direction, the two sides of the battery sheet are respectively a first side and a second side, the scanning path includes a first path moving from a first point on the first side to a second point on the second side, a second path moving backward from the second point to a third point, and a third path moving from the third point to the first side, the first point is a starting point and an end point of the scanning path, and the third path moves from the third point to the first point;

[0025] The first path extends obliquely from the rear to the front or is parallel to the lateral direction, and the third path extends obliquely from the rear to the front.

[0026] Beneficial effects:

[0027] The laser sintering module, battery cell laser sintering equipment and method provided by the present invention can convey the battery cell while applying voltage to the battery cell, so that the laser emitted by the laser component can complete the scanning of the entire battery cell. Only one set of laser components is needed for the whole process, thereby reducing the manufacturing cost of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic structural diagram of a laser sintering module provided for one embodiment of the present invention;

[0029] Figure 2 A front view of a laser sintering module provided in one embodiment of the present invention;

[0030] Figure 3for Figure 2 A front view of the upper roller or the lower roller in FIG.

[0031] Figure 4 for Figure 2 A side view of the laser sintering module in FIG.

[0032] Figure 5 for Figure 2 Schematic diagram of the circuit structure of the laser sintering module;

[0033] Figure 6 for Figure 2 A top view of the upper roller and solar cells of the laser sintering module;

[0034] Figure 7 A front view of a laser sintering module provided in yet another embodiment of the present invention;

[0035] Figure 8 for Figure 7 A side view of the laser sintering module in FIG.

[0036] Fig. 9 Figure 7 Schematic diagram of the circuit structure of the laser sintering module;

[0037] Fig.10 for Figure 7 A top view of the upper roller and solar cells of the laser sintering module;

[0038] Fig.11 A front view of a laser sintering module provided in yet another embodiment of the present invention;

[0039] Fig.12 for Fig.11 A side view of the laser sintering module in FIG.

[0040] Fig.13 for Fig.11 Schematic diagram of the circuit structure of the laser sintering module;

[0041] Fig.14 for Fig.11 A top view of the upper roller and solar cells of the laser sintering module;

[0042] Fig.15 A top view of an upper roller and a battery cell in a laser sintering module in another embodiment of the present invention;

[0043] Fig.16 A side view of a laser sintering module provided in yet another embodiment of the present invention;

[0044] Fig.17 for Fig.16 Schematic diagram of the circuit structure of the laser sintering module;

[0045] Fig.18 A schematic diagram of a scanning path on a battery cell provided by an embodiment of the present invention;

[0046] Fig.19 A schematic diagram of a scan path provided by yet another embodiment of the present invention;

[0047] Fig. 20 For the spot Fig.18 The schematic diagram of the movement track and the scanned area on the battery cell when the scanning path is cyclically scanned is shown;

[0048] Fig.21 For the spot Fig. 20 The scanning path shown is a schematic diagram of the movement trajectory on the battery cell and the scanned area when the scanning path is scanned in a loop. DETAILED DESCRIPTION

[0049] The present invention will be described in detail below in conjunction with the embodiments shown in the accompanying drawings. However, the embodiments do not limit the present invention, and any changes in mechanism, method, or function made by a person skilled in the art according to the embodiments are all within the protection scope of the present invention.

[0050] The terms used herein, such as "upper", "lower", "left", "right", "front", "back", etc., which indicate relative spatial positions, are used for the purpose of convenience to describe the relationship between one feature and another feature as shown in the accompanying drawings. It is understood that, depending on the placement of the product, the terms of relative spatial positions may be intended to include different orientations other than those shown in the drawings, and should not be construed as limitations on the claims. In addition, the descriptor "horizontal" used herein is not completely equivalent to being perpendicular to the direction of gravity, and a certain angle of inclination is allowed.

[0051] This embodiment provides a laser sintering device, which is used to perform laser sintering operations on a battery cell 600 and includes a laser sintering module 300 .

[0052] like Figure 1-17 As shown, the laser sintering module 300 includes at least two groups of powered roller assemblies 302 arranged along the front-to-back direction, and a laser assembly 301 for emitting laser light between the two groups of powered roller assemblies 302 .

[0053] The power roller assembly 302 includes an upper roller 302a and a lower roller 302b that are arranged opposite to each other in the up-down direction. The upper roller 302a and the lower roller 302b are driven to rotate by a transmission assembly (not shown in the figure). When the battery sheet 600 is arranged between the upper roller 302a and the lower roller 302b, the upper roller 302a and the lower roller 302b will drive the battery sheet 600 to move in the front-back direction.

[0054] The laser assembly 301 includes a laser source 301a, a laser shaping module 301b, a galvanometer 301c and a field lens 301d. The laser source 301a is used to emit laser light, the laser shaping module 301b is used to shape the spot of the laser light emitted by the laser source 301a into a square or a circle, the galvanometer 301c is used to receive the shaped laser light and adjust the scanning position, scanning amplitude and scanning speed of the laser spot according to the scanning parameters, and the field lens 301d is fixedly connected to the galvanometer 301c and is used to focus the laser light onto the surface of the battery cell 600 to form a spot on the surface of the battery cell 600. The spot of the laser light can be strip-shaped or dot-shaped.

[0055] The powered roller assembly 302 can drive the entire battery cell 600 to pass through the laser irradiation area, so that the laser can complete the scanning of the entire battery cell 600.

[0056] In this embodiment, the wavelength of the laser emitted by the laser component 301 is 400nm-1200nm, the size of the laser spot in the front-to-back direction is 0.01mm-10mm, and the power of the laser component 301 is 10W-300W.

[0057] The laser can be a continuous laser or a pulsed laser, which are emitted by a continuous laser or a pulsed laser respectively. In this embodiment, a pulsed laser is preferably used, and the frequency of the laser emitted by the pulsed laser is 50KHZ-4000KHZ. The energy applied to the battery cell 600 by the pulsed laser is moderate.

[0058] Specifically, the upper roller 302a and the lower roller 302b each include a rotating shaft 3020, and a contact ring 3024 sleeved on the rotating shaft 3020 for contacting the battery cell 600. Each upper roller 302a and each lower roller 302b are each provided with only one contact ring 3024, wherein the contact ring 3024 on the upper roller 302a is a first contact ring 3024a, and the contact ring 3024 on the lower roller 302b is a second contact ring 3024b. On the battery cell 600, the surface contacted by the first contact ring 3024a is the front surface, and the surface contacted by the second contact ring 3024b is the back surface. The outer peripheral surface of the contact ring 3024 is annular and has a width extending in the transverse direction, and the transverse direction is perpendicular to the front-back direction. In this way, the contact ring 3024 has a sufficient contact area to contact the battery cell 600 , so that the battery cell 600 is not easily crushed, and the contact ring 3024 also has a sufficient area to contact the battery cell 600 to apply voltage to the battery cell 600 .

[0059] It should be noted that, in this article, the front-to-back direction refers to the direction in which the laser sintering module 300 is located. Figure 4 The left and right directions in the state shown, where the left side is the rear side, the right side is the front side, and the transverse direction is the laser sintering module 300 in the state shown Figure 2 Left and right direction in the displayed state.

[0060] The laser sintering module 300 further includes a power supply 302c, at least one of all the first contact rings 3024a is electrically connected to one of the positive and negative electrodes of the power supply 302c, and at least one of all the second contact rings 3024b is electrically connected to the other of the positive and negative electrodes of the power supply 302c. In this way, when the power roller assembly 302 conveys the battery cell 600, the power supply 302c can apply voltage to the battery cell 600 through at least one first contact ring 3024a and at least one second contact ring 3024b.

[0061] The voltage is applied to the cell 600, specifically, a reverse voltage is applied to the front and back sides of the cell 600, and the voltage value is 10V-30V. When the reverse voltage is applied, the area on the cell 600 irradiated by the laser will generate an induced current, and when the induced current flows through the area with high resistance on the cell 600, that is, the junction between the gate electrode and the silicon wafer, a large amount of heat will be generated, and the gate electrode and the silicon wafer will be sintered, thereby reducing the contact resistance between the gate electrode and the silicon wafer, and improving the fill factor and conversion efficiency of the cell 600.

[0062] In a specific configuration, the negative pole of the power source 302c is electrically connected to the first contact ring 3024a, and the positive pole is electrically connected to the second contact ring 3024b, or the positive pole of the power source 302c is electrically connected to the first contact ring 3024a, and the negative pole is electrically connected to the second contact ring 3024b.

[0063] The rotating shaft 3020 includes a main shaft 3021, an insulating layer 3022 sleeved on the main shaft 3021, and a conductive layer 3023 sleeved on the insulating layer 3022. The contact ring 3024 is sleeved on the conductive layer 3023. The power source 302c is connected to the contact ring 3024 through the conductive layer 3023. At least one of the conductive layers 3023 on all the upper rollers 302a is electrically connected to one of the positive and negative electrodes of the power source 302c, and at least one of the conductive layers 3023 on all the lower rollers 302b is electrically connected to the other of the positive and negative electrodes of the power source 302c. The main shaft 3021 is a metal shaft with high structural strength. The insulating layer 3022 separates the main shaft 3021 and the conductive layer 3023, so that the main shaft 3021 will not be charged.

[0064] The insulating layer 3022 may be made of insulating rubber, the conductive layer 3023 may be made of copper, graphite, carbon fiber, aluminum, silver, etc., the contact ring 3024 may be made of conductive silicone rubber, copper, carbon fiber, etc. Conductive silicone rubber is preferred because it is conductive and flexible, so it is not easy to damage the battery cell 600.

[0065] Conductive silicone rubber refers to silicone rubber in which conductive particles such as silver-plated glass, silver-plated aluminum, silver-plated copper, and pure silver are uniformly distributed. According to the different particles filled, conductive silicone rubber can be divided into silver-plated glass conductive silicone rubber, silver-plated aluminum conductive silicone rubber, silver-plated copper conductive silicone rubber, and pure silver conductive silicone rubber. In this embodiment, the contact ring 3024 is preferably made of silver-plated copper conductive silicone rubber.

[0066] The thickness of the battery cell 600 is very small, usually about 100 μm. Therefore, in order to contact the battery cell 600, the gap between the first contact ring 3024a and the second contact ring 3024b opposite to each other needs to be set to be very small so that the first contact ring 3024a and the second contact ring 3024b can directly contact each other. In the specific design, it is necessary to avoid the first contact ring 3024a and the second contact ring 3024b opposite to each other from contacting and short-circuiting.

[0067] like Figure 2-6 As shown, in one embodiment of the present invention, all first contact rings 3024a are used to electrically connect one of the positive and negative electrodes of the power source 302c, and all second contact rings 3024b are used to electrically connect the other of the positive and negative electrodes of the power source 302c. In specific settings, all first contact rings 3024a can be used to electrically connect the negative electrode of the power source 302c, and all second contact rings 3024b can be used to electrically connect the positive electrode of the power source 302c. Alternatively, all first contact rings 3024a can be used to electrically connect the positive electrode of the positive and negative electrodes of the power source 302c, and all second contact rings 3024b can be used to electrically connect the negative electrode of the positive and negative electrodes of the power source 302c.

[0068] The laser sintering module 300 further includes a plurality of switch elements 302d, and a switch element 302d is provided between at least one of the first contact ring 3024a and the second contact ring 3024b that are opposite to each other and the power source 302c. The switch element 302d can control the on-off between at least one of the first contact ring 3024a and the second contact ring 3024b that are opposite to each other and the power source 302c, so as to prevent a short circuit from occurring when the first contact ring 3024a and the second contact ring 3024b are in contact with each other.

[0069] The switch element 302d may be disposed between the second contact ring 3024b and the power source 302c, or between the first contact ring 3024a and the power source 302c, or between the first contact ring 3024a and the power source 302c and between the second contact ring 3024b and the power source 302c.

[0070] When the power roller assembly 302 conveys the battery cell 600, if there is a battery cell 600 between the first contact ring 3024a and the second contact ring 3024b, the switch element 302d is in a closed state. At this time, the first contact ring 3024a and the second contact ring 3024b are both connected to the power source 302c, so that the first contact ring 3024a and the second contact ring 3024b can apply voltage to the battery cell 600. If there is no battery cell 600 between the first contact ring 3024a and the second contact ring 3024b, the switch element 302d is in an open state. At this time, at least one of the first contact ring 3024a and the second contact ring 3024b is disconnected from the power source 302c, and no short circuit will occur when the two are in contact.

[0071] The switch element 302d is preferably a solid-state relay. The laser sintering module 300 may further include a control unit (such as a PLC) electrically connected to the solid-state relay. The control unit controls the on-off between the contact ring 3024 and the power source 302c through the solid-state relay.

[0072] Furthermore, the laser sintering module 300 also includes a sensing element 302e, which is arranged between the first group of powered roller assemblies 302 and the second group of powered roller assemblies 302 from back to front, so as to determine whether there is a battery cell 600 between the first group of powered roller assemblies 302 and the second group of powered roller assemblies 302.

[0073] The sensing element 302e is electrically connected to the control unit. When the sensing element 302e senses the battery cell 600, the first contact ring 3024a and the second contact ring 3024b of the first group of power-on roller assembly 302 are both connected to the power source 302c. The subsequent control unit can calculate the position of the battery cell 600 at each subsequent moment according to the transmission speed of the battery cell 600, the size of the battery cell 600, and the distance of the power-on roller assembly 302 in the front-to-back direction, so that only when there is a battery cell 600 between the first contact ring 3024a and the second contact ring 3024b opposite to each other, both are connected to the power source 302c. When the battery cell 600 is about to leave between the first contact ring 3024a and the second contact ring 3024b opposite to each other, the electrical connection between at least one of the first contact ring 3024a and the second contact ring 3024b and the power source 302c is disconnected. In this way, no short circuit occurs between the first contact ring 3024a and the second contact ring 3024b opposite to each other.

[0074] The sensing element 302e is not limited to being disposed between the first group of powered roller components 302 and the second group of powered roller components 302 from back to front, but may also be disposed behind the first group of powered roller components 302 from back to front.

[0075] In this embodiment, the battery cell 600 is an MBB type battery cell. This type of battery cell 600 includes a main grid line and a fine grid line forming a network structure, wherein the extension direction of the main grid line ( Figure 6 The thick line portion in the cell 600) is consistent with the transmission direction of the cell 600, and the thin grid line ( Figure 6 The thin line portion in the battery cell 600 extends in the lateral direction.

[0076] In this embodiment, the contact ring 3024 on the upper roller 302a and the lower roller 302b can apply voltage to the fine grid lines by contacting multiple main grid lines. In this case, the length of the contact ring 3024 (i.e., the size of the contact ring 3024 in the lateral direction) is smaller than the size of the battery cell 600 in the lateral direction.

[0077] like Figure 7-10 As shown, in another embodiment of the present invention, the first contact ring 3024a and the second contact ring 3024b that are opposite to each other have different lengths, one is longer and the other is shorter, wherein the upper roller shaft 302a or the lower roller shaft 302b where the shorter contact ring 3024 is located is provided with two insulating sleeves 3024c located on both sides of the contact ring 3024 respectively.

[0078] For convenience of explanation, the longer contact ring 3024 is called a long contact ring, and the shorter contact ring 3024 is called a short contact ring. The length of the long contact ring is greater than the size of the battery cell 600 in the lateral direction, and both ends in the length direction exceed the edge of the battery cell 600. The length of the short contact ring is less than the size of the battery cell 600 in the lateral direction, and both ends in the length direction do not exceed the edge of the battery cell 600. The length of the long contact ring is equal to the length of the short contact ring plus the length of the two insulating sleeves 3024c.

[0079] For example, if the lateral dimension of the battery cell 600 is 182 mm, the length of the long contact ring needs to be greater than 182 mm, preferably 186 mm, the length of the short contact ring needs to be less than 182 mm, preferably 170 mm, and the length of the insulating sleeves 3024c on both sides is 8 mm.

[0080] To facilitate the distinction, Figure 7-10 In the figure, portions of the insulating sleeve 3024c are hatched.

[0081] The laser powered roller assembly 302 of this embodiment is suitable for applying voltage to 0BB type battery sheets. Fig.10 As shown, the difference between this type of battery cell 600 and the above-mentioned MBB type battery cell is that the 0BB type battery cell has no main grid but only fine grids. When voltage is applied to it, the contact ring 3024 needs to contact all the fine grids. Therefore, the length of the contact ring 3024 needs to be greater than the size of the battery cell 600 in the lateral direction.

[0082] It can be imagined that the laser powered roller assembly 302 of this embodiment is suitable for applying voltage to 0BB type battery cells, and is also suitable for applying voltage to MBB type battery cells.

[0083] In this embodiment, among the long contact ring and the short contact ring that are opposite to each other, the length of the long contact ring is greater than the dimension of the battery cell 600 in the lateral direction, and it can contact all the fine grid lines, while the length of the short contact ring is less than the dimension of the battery cell 600 in the lateral direction. The part of the long contact ring that exceeds the battery cell 600 contacts the insulating sleeve 3024c, so that a short circuit will not occur between the upper roller 302a and the lower roller 302b.

[0084] Among the upper roller 302a and the lower roller 302b, the one with a longer contact ring 3024 is the first roller 302-L, and the one with a shorter contact ring 3024 is the second roller 302-S. In order to ensure that all fine grid lines on both sides of the battery cell 600 can contact the contact ring 3024, at least one of all the upper rollers 302a is the first roller 302-L, and at least one of all the lower rollers 302b is the first roller 302-L.

[0085] In this embodiment, the power roller assembly 302 is provided with four groups along the front-to-back direction and is evenly arranged. The arrangement rules of the four upper rollers 302a and the four lower rollers 302b from back to front are as follows: the first upper roller 302a and the fourth upper roller 302a are the second roller 302-S, the second upper roller 302a and the third upper roller 302a are the first roller 302-L, the first lower roller 302b and the fourth lower roller 302b are the first roller 302-L, and the second lower roller 302b and the third lower roller 302b are the second roller 302-S. The laser assembly 301 is used to emit laser between the second upper roller 302a and the third upper roller 302a to irradiate the front of the battery cell 600.

[0086] With the above arrangement, the four areas where voltage is loaded on the front side of the cell 600 (i.e., the areas where the four upper rollers 302a are in contact with the front side of the cell 600) are symmetrically arranged on both sides of the area where the cell 600 is irradiated by the laser. This is beneficial to the sintering between the gate electrode on the cell 600 and the silicon wafer.

[0087] If the first contact ring 3024a and the second contact ring 3024b on a certain group of power-on roller assemblies 302 are both electrically connected to the power source 302c, the group of power-on roller assemblies 302 is said to be powered on. When the above four groups of power-on roller assemblies 302 convey the battery cell 600 from the back to the front, if the sensing element 302e senses the battery cell 600, the battery cell 600 is already located between the upper roller 302a and the lower roller 302b of the first group of power-on roller assemblies 302, so the first group of power-on roller assemblies 302 can be powered on, and then as the battery cell 600 continues to move forward, the front side of the battery cell 600 passes through the second group of power-on roller assemblies 302, the third group of power-on roller assemblies 302, and the fourth group of power-on roller assemblies 302 in sequence, and the second group of power-on roller assemblies 302, the third group of power-on roller assemblies 302, and the fourth group of power-on roller assemblies 302 are powered on in sequence.

[0088] During the conveying process of the battery cell 600 from back to front, the rear side of the battery cell 600 will leave the first group of power-on roller assemblies 302, the second group of power-on roller assemblies 302, the third group of power-on roller assemblies 302, and the fourth group of power-on roller assemblies 302 in sequence. Therefore, during the conveying process of the battery cell 600, the first group of power-on roller assemblies 302, the second group of power-on roller assemblies 302, the third group of power-on roller assemblies 302, and the fourth group of power-on roller assemblies 302 are powered off in sequence.

[0089] It can be understood that the number of the powered roller assemblies 302 can be two, three, five or even more.

[0090] In addition to the above-mentioned arrangement rules, in another embodiment of the present invention, the arrangement rule of the four upper rollers 302a and the four lower rollers 302b from back to front can also be: the first upper roller 302a and the third upper roller 302a are the second roller 302-S, the second upper roller 302a and the fourth upper roller 302a are the first roller 302-L, the first lower roller 302b and the third lower roller 302b are the first roller 302-L, and the second lower roller 302b and the fourth lower roller 302b are the second roller 302-S.

[0091] In another embodiment of the present invention, the arrangement pattern of the four upper rollers 302a and the four lower rollers 302b from back to front can also be: the first upper roller 302a and the third upper roller 302a are the first roller 302-L, the second upper roller 302a and the fourth upper roller 302a are the second roller 302-S, the first lower roller 302b and the third lower roller 302b are the second roller 302-S, and the second lower roller 302b and the fourth lower roller 302b are the first roller 302-L.

[0092] In another embodiment of the present invention, the arrangement rule of the upper rollers 302a and the lower rollers 302b may also be: all the upper rollers 302a are the first rollers 302-L, and all the lower rollers 302b are the second rollers 302-S.

[0093] In another embodiment of the present invention, the arrangement pattern of the four upper rollers 302a and the four lower rollers 302b from back to front may also be: the first upper roller 302a and the fourth upper roller 302a are the first roller 302-L, the second upper roller 302a and the third upper roller 302a are the second roller 302-S, the first lower roller 302b and the fourth lower roller 302b are the second roller 302-S, and the second lower roller 302b and the third lower roller 302b are the first roller 302-L.

[0094] like Figure 11-16 As shown, in one embodiment of the present invention, only one of the first contact ring 3024a and the second contact ring 3024b that are opposite to each other is electrically connected to the positive or negative pole of the power source 302c, and the other is not electrically connected to the power source 302c. In this way, when the first contact ring 3024a and the second contact ring 3024b that are opposite to each other are in contact, no short circuit will occur.

[0095] It should be noted that, of the first contact ring 3024a and the second contact ring 3024b, the one electrically connected to the power source 302c may be made of a conductive material, and the one not electrically connected to the power source 302c may be made of an insulating material. It is understandable that the first contact ring 3024a and the second contact ring 3024b may also be made of the same conductive material.

[0096] To facilitate the distinction, Figure 11-16 In the figure, the contact ring 3024 which is not electrically connected to the power source 302c is marked with a cross-hatching line.

[0097] In this embodiment, the lengths of the first contact ring 3024a and the second contact ring 3024b are the same and are both smaller than the size of the battery cell 600 in the lateral direction. Thus, the power roller assembly 302 of this embodiment is suitable for applying voltage (such as Fig.14 shown).

[0098] In other embodiments, the first contact ring 3024a and the second contact ring 3024b may also be larger than the size of the battery cell 600 in the lateral direction. The power roller assembly 302 of this embodiment is suitable for applying voltage to the above-mentioned 0BB type battery cell (such as Fig.15 shown).

[0099] It can be imagined that the laser powered roller assembly 302 of this embodiment is suitable for applying voltage to 0BB type battery cells, and is also suitable for applying voltage to MBB type battery cells.

[0100] Specifically, Figure 12-15 As shown, the power roller assembly 302 is provided with four groups along the front-to-back direction and is evenly arranged. The arrangement rule of the four first contact rings 3024a and the four second contact rings 3024b from back to front is: the second first contact ring 3024a and the third first contact ring 3024a are electrically connected to one of the positive and negative poles of the power supply 302c, and the first second contact ring 3024b and the fourth second contact ring 3024b are electrically connected to the other of the positive and negative poles of the power supply 302c. The laser assembly 301 is used to emit laser between the second upper roller 302a and the third upper roller 302a to irradiate the front of the battery cell 600.

[0101] With the above arrangement, two areas where voltage is loaded on the front side of the battery cell 600 (i.e., the areas where the second first contact ring 3024a and the third first contact ring 3024a are in contact with the front side of the battery cell 600) are symmetrically arranged on both sides of the area where the battery cell 600 is irradiated with the laser, and are close to the area where the battery cell 600 is irradiated with the laser. This is beneficial to the sintering between the gate electrode on the battery cell 600 and the silicon wafer.

[0102] Since the grid lines on the MBB type battery cell are half-cell designs, the axial center distance between two adjacent groups of power-on roller assemblies 302 is no greater than half of the size of the battery cell 600 in the front-to-back direction, to ensure that the battery cell 600 can always remain in a state of loading voltage during the transmission process.

[0103] In addition to the above arrangement rules, Fig.16 As shown, in another embodiment of the present invention, the arrangement rule of the four first contact rings 3024a and the four second contact rings 3024b from back to front can also be: the second first contact ring 3024a and the fourth first contact ring 3024a are electrically connected to one of the positive and negative poles of the power supply 302c, and the first second contact ring 3024b and the third second contact ring 3024b are electrically connected to the other of the positive and negative poles of the power supply 302c.

[0104] In another embodiment of the present invention, the arrangement rule of the four first contact rings 3024a and the four second contact rings 3024b from back to front can also be: the first first contact ring 3024a and the third first contact ring 3024a are electrically connected to one of the positive and negative poles of the power supply 302c, and the second second contact ring 3024b and the fourth second contact ring 3024b are electrically connected to the other of the positive and negative poles of the power supply 302c.

[0105] In another embodiment of the present invention, the arrangement rule of the four first contact rings 3024a and the four second contact rings 3024b from back to front can also be: the first first contact ring 3024a and the fourth first contact ring 3024a are electrically connected to one of the positive and negative poles of the power supply 302c, and the second second contact ring 3024b and the third second contact ring 3024b are electrically connected to the other of the positive and negative poles of the power supply 302c.

[0106] In summary, the laser sintering module and battery cell laser sintering equipment provided by the present invention can convey the battery cell 600 while applying voltage to the battery cell 600, so that the laser emitted by the laser component 301 can complete the scanning of the entire battery cell 600. Only one set of laser components 301 is needed for the whole process, thereby reducing the manufacturing cost of the equipment.

[0107] like Figure 18-21 As shown, the present invention provides a method for laser sintering a battery cell 600, which uses the above-mentioned battery cell laser sintering equipment and includes the following steps:

[0108] Applying voltage to the battery cell 600 and conveying the battery cell 600 from back to front in the front-back direction, Figure 18-21 The arrow on the right shows the anterior-posterior direction;

[0109] The laser is emitted toward the battery cell 600. When the laser is emitted, a dot-shaped light spot is formed on the plane where the battery cell 600 is located. When the light spot is located on the battery cell 600, a certain area on the battery cell 600 will be correspondingly irradiated. For example, when the laser irradiates the battery cell 600 from top to bottom, a certain area on the upper surface of the battery cell 600 will be correspondingly irradiated.

[0110] The laser is moved so that the light spot performs multiple cycles of scanning along a preset scanning path.

[0111] The voltage is applied to the cell 600, specifically, a reverse voltage is applied to the front and back sides of the cell 600, and the voltage value is preferably 10V-30V. When the reverse voltage is applied, the area on the cell 600 irradiated by the laser will generate an induced current, and when the induced current flows through the area with high resistance on the cell 600, that is, the junction between the gate electrode and the silicon wafer, a large amount of heat will be generated, and the gate electrode and the silicon wafer will be sintered, thereby reducing the contact resistance between the gate electrode and the silicon wafer, so that the fill factor and conversion efficiency of the cell 600 can be improved.

[0112] In the transverse direction perpendicular to the front-rear direction, the two sides of the battery cell 600 are respectively the first side and the second side. Fig.18 The middle is the left and right direction, Fig.18In the embodiment, the left side of the battery cell 600 is the first side, and the right side is the second side. In other embodiments, the right side of the battery cell 600 may be the first side, and the left side may be the second side.

[0113] The scanning path includes a first path S1 moving from a first point O1 on the first side to a second point O2 on the second side, a second path S2 moving backward from the second point O2 to a third point O3, and a third path S3 moving from the third point O3 to the first side. The scanning path is a closed-loop path, and the first point O1 is the starting point and the end point of the scanning path, that is, after the irradiation point moves from the second side to the first side along the third path S3, it will return to the first point O1.

[0114] The first path S1 extends obliquely from the back to the front or is parallel to the transverse direction, and the third path S3 extends obliquely from the back to the front.

[0115] When the battery cell 600 is transported from the back to the front, the light spot moves from the first point O1 on the first side to the second point O2 on the second side along the first path S1, and scans a part of the battery cell 600 and radiates the scanned area. After passing through the first path S1, the light spot moves from the front to the back along the second path S2, and then moves from the back to the front along the third path S3. In this way, the area on the battery cell 600 scanned by the light spot along the third path S3 can be prevented from overlapping with the area on the battery cell 600 previously scanned by the light spot along the first path S1. The light spot can scan as many areas on the battery cell 600 as possible, and the scanning path can eventually return to the first point O1.

[0116] It should be understood that when the light spot moves along the first path S1 or the third path S3, if the movement of the battery cell 600 from back to front is synchronized with the movement of the light spot from back to front, the area swept by the light spot on the battery cell 600 is parallel to the lateral direction; if the movement of the battery cell 600 from back to front is not synchronized with the movement of the light spot from back to front, the area swept by the light spot on the battery cell 600 is inclined relative to the lateral direction.

[0117] like Fig.18 As shown, in one embodiment of the present invention, the third path S3 moves from the third point O3 to the first point O1. Thus, the scanning path is triangular, and the light spot is cyclically scanned along the triangular scanning path.

[0118] Specifically, the first path S1 extends obliquely from the back to the front, and when the light spot moves along the first path S1, it not only moves from the first side to the second side in the transverse direction, but also moves forward a certain distance in the front-to-back direction. As described above, the third path S3 extends obliquely from the back to the front, and when the light spot moves along the third path S3, it not only moves from the second side to the first side in the transverse direction, but also moves forward a certain distance in the front-to-back direction.

[0119] The distance between the first point O1 and the second point O2 in the front-to-back direction and the distance between the third point O3 and the first point O1 in the front-to-back direction are both equal to 0.5H. It can be imagined that in the above case, the distance between the second point O2 and the third point O3 in the front-to-back direction is H. During the process of the light spot completing one scan, the battery cell 600 moves forward by a distance of H.

[0120] In this embodiment, both ends of the first path S1 and both ends of the third path S3 extend beyond the battery cell 600 in the lateral direction. Thus, when the light spot moves along the first path S1 and the third path S3, it can completely scan the battery cell 600 in the lateral direction. The light spot scans in a cycle multiple times along the scanning path, and the scanned area can cover the battery cell 600.

[0121] Those skilled in the art can imagine that the length of the first path S1 and the length of the third path S3 are related to the size of the battery cell 600 in the transverse direction, and the length of the second path S2 (i.e., the distance between the second point O2 and the third point O3 in the front-to-back direction) is related to the size H of the light spot in the front-to-back direction. For example, in this embodiment, the size of the battery cell 600 in the transverse direction is 182 mm, the length of the first path S1 and the third path S3 is slightly larger than 182 mm, about 190 mm, and the direction of the second path S2 is equal to H, which is 2.5 mm. Obviously, the length of the first path S1 and the length of the third path S3 are much larger than the length of the second path S2. Therefore, in the process of the light spot moving along the scanning path, most of the time is spent moving along the first path S1 and the third path S3, and the time moving along the second path S2 and the third path S3 can be ignored.

[0122] Specifically, the ratio of the length of the first path or the third path to the size H of the light spot in the front-to-back direction is not less than 10.

[0123] In this embodiment, the lengths of the first path S1 and the third path S3 are equal. If the battery cell 600 moves forward at a uniform speed, the distance H that the battery cell 600 moves forward during the process of the light spot completing one scan can be divided into: when the light spot moves from the first point O1 to the second point O2 along the first path S1, the battery cell 600 moves forward by a distance of 0.5H, and when the light spot moves from the third point O3 to the first point O1 along the third path S3, the battery cell 600 moves forward by a distance of 0.5H. Since the distance that the light spot moves forward when it moves along the first path S1 is 0.5H, and the distance that the light spot moves forward when it moves along the third path S3 is 0.5H, when the light spot moves along the first path S1 and the third path S3, the battery cell 600 moves synchronously with the light spot. In this way, when the light spot scans cyclically according to the scanning path, the several strip areas that the light spot scans on the battery cell 600 are parallel to the horizontal direction and cover the battery cell 600, and the light spot can basically scan all areas of the battery cell 600. When the light spot is scanned according to the scanning path of this embodiment, the moving track on the battery cell 600 and the schematic diagram of the scanning area are as follows: Fig. 20 shown.

[0124] In another embodiment of the present invention, Fig.19 As shown, the difference between this embodiment and the previous embodiment is that, in this embodiment, the first path S1 is parallel to the transverse direction, that is, the distance between the first point O1 and the second point O2 in the front-to-back direction is 0, and the light spot moves along the first path S1, and moves from the first side to the second side in the transverse direction, but its position in the front-to-back direction remains unchanged. The distance between the third point O3 and the first point O1 in the front-to-back direction is H, and the light spot moves along the third path S3, not only from the second side to the first side, but also moves forward a distance of H in the front-to-back direction.

[0125] In this embodiment, the length of the third path S3 is slightly greater than the length of the first path S1. If the battery cell 600 moves forward at a constant speed, the distance H that the battery cell 600 moves forward during the process of the light spot completing a scan can be divided into: when the light spot moves from the first point O1 to the second point O2 along the first path S1, the distance that the battery cell 600 moves forward is 0.5H, and when the light spot moves from the third point O3 to the first point O1 along the third path S3, the distance that the battery cell 600 moves forward is 0.5H. Since the light spot moves forward 0 when it moves along the first path S1, the movement of the battery cell 600 and the light spot is not synchronized, and the movement distances of the two differ by 0.5H. Accordingly, the strip area that the light spot scans on the battery cell 600 extends obliquely from front to back relative to the horizontal direction. Since the light spot moves forward by a distance of H when it moves along the third path S3, the movement of the cell 600 and the light spot is also not synchronized, and the movement distances of the two are also different by 0.5H. Accordingly, the strip area swept by the light spot on the cell 600 extends from the back to the front relative to the horizontal direction. When the light spot scans according to the scanning path of this embodiment, the moving track on the cell 600 and the schematic diagram of the swept area are as follows: Fig.21 shown.

[0126] When the light spot scans cyclically according to the scanning path of this embodiment, the strip area swept on the battery when the light spot moves along the first path S1 and the strip area swept on the battery cell 600 when the light spot moves along the third path S3 are parallel and cover the battery cell 600, and the light spot can basically sweep all areas of the battery cell 600.

[0127] In summary, the battery cell laser sintering method provided by the present invention applies voltage to the battery cell 600 during the transportation of the battery cell 600, and during the transportation of the battery cell 600, a laser with a point-shaped light spot is moved according to a preset scanning path. The area scanned by the laser can cover the battery cell 600 well, and the energy applied to the battery cell 600 is moderate.

[0128] It should be understood that although the present specification is described according to embodiments, not every embodiment contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0129] The above embodiments are only used to illustrate the technical solution of the present application and are not intended to limit it. Although the present application has been described in detail with reference to the preferred embodiments, a person skilled in the art should understand that the technical solution of the present application may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present application.

Claims

1. A laser sintering module, characterized in that: It comprises at least two groups of powered roller shaft assemblies arranged in the front-to-back direction, and a laser assembly for emitting laser light between the two groups of powered roller shaft assemblies; The power-on roller assembly comprises an upper roller and a lower roller which are arranged opposite to each other in the up-down direction, wherein the upper roller and the lower roller each comprise a rotating shaft and a contact ring which is sleeved on the rotating shaft and is used to contact the battery sheet, and each upper roller and each lower roller is provided with only one contact ring, the contact ring on the upper roller is a first contact ring, and the contact ring on the lower roller is a second contact ring; The laser sintering module also includes a power supply, at least one of all the first contact rings is electrically connected to one of the positive and negative electrodes of the power supply, and at least one of all the second contact rings is electrically connected to the other of the positive and negative electrodes of the power supply.

2. The laser sintering module according to claim 1, characterized in that: All first contact rings are used to electrically connect one of the positive and negative poles of a power source, and all second contact rings are used to electrically connect the other of the positive and negative poles of a power source. The laser sintering module also includes a plurality of switching elements, and the switching element is arranged between at least one of the first and second contact rings that are opposite to each other up and down and the power source.

3. The laser sintering module according to claim 2, characterized in that: The laser sintering module also includes a sensing element, which is arranged between the first group of powered roller assemblies and the second group of powered roller assemblies from back to front, so as to determine whether there is a battery cell between the first group of powered roller assemblies and the second group of powered roller assemblies.

4. The laser sintering module according to claim 2, characterized in that: The first contact ring and the second contact ring opposite to each other have different lengths, wherein the upper roller shaft or the lower roller shaft where the shorter contact ring is located is sleeved with two insulating sleeves respectively located on both sides of the contact ring; Among the upper roller and the lower roller, the one with a longer contact ring is the first roller, and the one with a shorter contact ring is the second roller. Among all the upper rollers, at least one is the first roller, and among all the lower rollers, at least one is the first roller.

5. The laser sintering module according to claim 4, characterized in that: The length of the shorter contact ring plus the length of the two insulating sleeves is equal to the length of the longer contact ring.

6. The laser sintering module according to claim 4, characterized in that: The powered roller shaft assembly is provided with four groups along the front-to-back direction and is evenly arranged. Among the four upper roller shafts from the back to the front, the first upper roller shaft and the fourth upper roller shaft are the second roller shafts, the second upper roller shaft and the third upper roller shaft are the first roller shafts, and among the four lower roller shafts from the back to the front, the first lower roller shaft and the fourth lower roller shaft are the first roller shafts, and the second lower roller shaft and the third lower roller shaft are the second roller shafts; The laser assembly is used for emitting laser light between the second upper roller and the third upper roller.

7. The laser sintering module according to claim 1, characterized in that: Only one of the first contact ring and the second contact ring that are opposite to each other up and down is electrically connected to the positive electrode or the negative electrode of the power source.

8. The laser sintering module according to claim 7, characterized in that: The power-on roller assembly is provided with four groups along the front-to-back direction and is evenly arranged. Among the four first contact rings and the four second contact rings from the back to the front, the second first contact ring and the third first contact ring are electrically connected to one of the positive and negative electrodes of the power supply, and the first second contact ring and the fourth second contact ring are electrically connected to the other of the positive and negative electrodes of the power supply; The laser assembly is used for emitting laser light between the second upper roller and the third upper roller.

9. The laser sintering module according to claim 1, characterized in that: The rotating shaft includes a main shaft, an insulating layer sleeved on the main shaft, and a conductive layer sleeved on the insulating layer. The contact ring is sleeved on the conductive layer. At least one of the conductive layers of all upper rollers is electrically connected to one of the positive and negative poles of the power supply, and at least one of the conductive layers of all lower rollers is electrically connected to the other of the positive and negative poles of the power supply.

10. A cell laser sintering device, characterized in that: The laser sintering module comprises any one of claims 1 to 9.

11. A method for laser sintering a battery cell, characterized in that: The cell laser sintering device according to claim 10 is used, and includes the following steps: Applying voltage to the battery cell and conveying the battery cell from back to front in a front-to-back direction; emitting a laser toward the battery cell, wherein when the laser is emitted, a dot-shaped light spot is formed on the plane where the battery cell is located; Moving the laser so that the light spot performs multiple cycles of scanning along a preset scanning path; Assuming that in a transverse direction perpendicular to the front-rear direction, the two sides of the battery sheet are respectively a first side and a second side, the scanning path includes a first path moving from a first point on the first side to a second point on the second side, a second path moving backward from the second point to a third point, and a third path moving from the third point to the first side, the first point is a starting point and an end point of the scanning path, and the third path moves from the third point to the first point; The first path extends obliquely from the rear to the front or is parallel to the lateral direction, and the third path extends obliquely from the rear to the front.

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