Battery piece lifting method

Abstract

The invention relates to the technical field of solar cells, and discloses a cell pulling method, which comprises the following steps: providing groove type equipment, the groove type equipment comprises a plurality of first processing grooves and a plurality of second processing grooves, and cells are alternately immersed in the first processing grooves and the second processing grooves; the battery piece immersed in the first machining groove in the vertical state is lifted upwards in a segmented mode in the vertical direction; the subsection lifting comprises a first-section lifting and a second-section lifting, the first-section lifting lifts the battery piece at a first speed until the lowest point of the battery piece is separated from the surface of tank liquid of the first processing tank, and the second-section lifting continues to lift the battery piece at a second speed; putting the lifted battery piece into a second processing groove; wherein one of the first processing tank and the second processing tank is a chemical tank, the other one of the first processing tank and the second processing tank is a water tank, and the ratio of the first speed to the second speed is 1: 6-1: 60. By adopting the pulling method, the liquid carrying amount of the battery piece can be reduced, the dilution degree of chemicals is reduced, and the utilization rate of the chemicals is increased.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of solar cells, in particular to a method for lifting a cell. BACKGROUND

[0002] The wet process is a process of using chemical solution to react with silicon wafer to achieve etching or cleaning effect. The process involves various types of reactions, and there is a high correlation between the reactions. Therefore, a tank type equipment is usually used for the wet process. The tank type equipment includes multiple chemical reaction tanks and water tanks. After the silicon wafer is reacted in the chemical tank, it is cleaned in the water tank. Therefore, by switching between the chemical tank and the water tank, the effect of the wet process is achieved while reducing the cross contamination of chemical reagents.

[0003] However, when the silicon wafer is switched between the tanks, the chemical reagent in the chemical tank will inevitably be brought into the water tank, and water will be brought into the chemical tank, thereby affecting the concentration and purity of the reagent in the chemical tank, and increasing the degree of pollution of the water tank, the frequency of liquid supplementing and replacing, and the production cost. SUMMARY

[0004] Embodiments of the present application disclose a method for lifting a cell, which reduces the liquid amount of the cell, reduces the dilution degree of chemicals, and increases the utilization rate of chemicals.

[0005] Embodiments of the present application disclose a method for lifting a cell, which reduces the liquid amount of the cell, reduces the dilution degree of chemicals, and increases the utilization rate of chemicals.

[0006] The cell immersed in the first processing tank in a vertical state is segmented and lifted upwards along the vertical direction. The segmented lifting includes first segment lifting and second segment lifting. The first segment lifting lifts the cell at a first speed until the lowest point of the cell is separated from the surface of the tank liquid in the first processing tank. The second segment lifting continues to lift the cell at a second speed.

[0007] The lifted cell is placed in the second processing tank. One of the first processing tank and the second processing tank is a chemical tank, and the other is a water tank. The ratio of the first speed to the second speed is 1:6-1:60.

[0008] Further, the first speed is 10-100 mm / s, and the second speed is 400-600 mm / s.

[0009] Further, after the first segment lifting is completed, the height H of the lowest point of the cell from the surface of the tank liquid is 5-30 mm.

[0010] Further, in the step of segmental pulling, the battery piece is perpendicular to the surface of the tank solution.

[0011] Further, the size of the battery piece is 150mm-210mm.

[0012] Further, after the step of segmental pulling is completed, the height from the highest point of the battery piece to the surface of the tank solution is 550mm-580mm.

[0013] Further, the tank device is used for a texturing process, and the solution in the chemical tank comprises chemical reagents, wherein the concentration of hydrofluoric acid is reduced by 40%-60% in terms of mass concentration, the concentration of additive is reduced by 4%-8%, the concentration of sodium hydroxide is reduced by 5%-9%, and the concentration of hydrogen peroxide is reduced by 10%-16%.

[0014] Further, in terms of ten thousand pieces of the battery piece, the consumption of hydrogen peroxide is reduced by 1.2L / wp-2.5L / wp, the consumption of additive is reduced by 0.05L / wp-0.4L / wp, the consumption of sodium hydroxide is reduced by 0.3L / wp-1.0L / wp, the consumption of hydrofluoric acid is reduced by 0.5L / wp-1.5L / wp, and the consumption of water is reduced by 0.01t / wp-0.1t / wp.

[0015] Further, the size of the battery piece is 183mm, in the step of the first segmental pulling, the first speed is 50mm / s, the height from the lowest point of the battery piece to the surface of the tank solution is 25mm, in the step of the second segmental pulling, the second speed is 500mm / s, and the height from the highest point of the battery piece to the surface of the tank solution is 565mm.

[0016] Further, the tank device further comprises a slow pulling tank arranged after the first processing tank and the second processing tank, and the lifting speed of the slow pulling tank is 3mm / s-5mm / s.

[0017] Compared with the prior art, the application has the beneficial effects that:

[0018] The application provides a pulling method of a battery piece, the battery piece immersed in a first processing tank in a vertical state is pulled out from the first processing tank along a vertical direction in two stages according to different pulling speeds respectively, and then is placed into a second processing tank, and by controlling the pulling speed ratio in different stages, the liquid carrying condition of the battery piece pulled out from the processing tank is reduced.

[0019] The first processing tank and the second processing tank are a chemical tank and a water tank respectively, so that the battery piece is alternately pulled in the chemical tank and the water tank, the chemical reagent of the battery piece pollutes the water tank, and the water of the water tank dilutes the chemical reagent of the chemical tank. The ratio of the first speed and the second speed is 1:6-1:60 in the segmented pulling process, wherein the first speed belongs to a relatively slow speed stage, the surface tension of the tank liquid is used to reduce the liquid carrying degree of the battery piece, so that the liquid carrying amount of the battery piece is reduced when the battery piece is switched between the chemical tank and the water tank, the dilution degree of the water into the chemical tank to the chemical reagent is reduced, and the pollution degree of the chemical reagent into the water tank to the water is reduced. The second speed belongs to a high speed stage, and the first speed to the second speed is an instantaneous acceleration stage, so that the tank liquid of the battery piece is in an over-weight state, the tank liquid on the battery piece is separated from the battery piece under the influence of gravity, thereby further reducing the liquid carrying degree of the battery piece, reducing the dilution degree of the chemical, and increasing the utilization rate of the chemical. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings used in the embodiments will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0021] Figure 1 is a schematic diagram of the battery piece pulled at a constant speed;

[0022] Figure 2 is a schematic diagram of the battery piece pulling method provided by the embodiments of the present application.

[0023] Icon: 1, mechanical arm; 2, first processing tank; 3, battery piece; 4, second processing tank. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0025] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "transverse", "longitudinal" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not intended to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0026] In addition, in addition to indicating the orientation or positional relationship, the above-mentioned partial terms may also be used to indicate other meanings, for example, the term "upper" may also be used to indicate a certain dependent relationship or connection relationship in some cases. For those skilled in the art, the specific meaning of these terms in the present application can be understood according to the specific situation.

[0027] In addition, the terms "first", "second" and the like are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not intended to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise stated, the meaning of "multiple" is two or more.

[0028] The technical solutions provided by the present application will be further described below in conjunction with the embodiments and the drawings.

[0029] The wet process of the solar cell is a cleaning process. In the wet process, multiple chemical reactions are involved, and each chemical reaction is mutually influenced and has a high correlation. Therefore, the silicon wafer needs to be washed after completing any chemical reaction, so as to enter the next chemical reaction stage. The water washing reduces the occurrence of side reactions, thereby making the effect of the wet process higher.

[0030] Especially for the wet process using a tank device as a reactor, the silicon wafer is switched back and forth between the chemical tank and the water tank. However, when the silicon wafer enters the water tank from the chemical tank, the chemical reagent is brought into the water tank, which pollutes the water in the water tank and affects the concentration of the chemical reagent in the chemical tank. When the silicon wafer enters the chemical tank from the water tank, if the water in the water tank is highly polluted, the chemical reagents will react with each other when the silicon wafer enters the chemical tank, thereby increasing the occurrence of side reactions and affecting the cleaning and etching effect of the chemical reagents on the silicon wafer. In addition, the introduction of the water from the water tank reduces the concentration of the chemical reagent in the chemical tank. A small amount of battery piece processing has a small effect on the cleaning and etching effect of the battery piece. However, as the number of battery pieces processed increases, the pollution degree of the chemical reagent in the chemical tank and the water in the water tank is higher. Therefore, the frequency of liquid supplementing and replacing in the tank device is increased, thereby increasing the production cost.

[0031] Based on the above problems, the application provides a pulling method of battery piece, to reduce the liquid amount of battery piece when switching between each tank, improve the utilization rate of chemical reagent in chemical tank and water in water tank, and reduce the production cost.

[0032] The pulling method of the application comprises: providing a tank device, the tank device comprising a plurality of first processing tanks and a plurality of second processing tanks, and the battery piece is alternately immersed in the first processing tank and the second processing tank.

[0033] The battery piece immersed in the first processing tank in a vertical state is segmented and pulled upward along the vertical direction; the segmented pulling comprises first segment pulling and second segment pulling, the first segment pulling pulls the battery piece at a first speed until the lowest point of the battery piece is separated from the tank liquid surface of the first processing tank, and the second segment pulling continues to pull the battery piece at a second speed.

[0034] The pulled battery piece is placed into the second processing tank; one of the first processing tank and the second processing tank is a chemical tank, and the other is a water tank, and the ratio of the first speed to the second speed is 1:6-1:60.

[0035] It can be understood that the battery piece enters a chemical tank for processing, then enters a water tank for cleaning, and then enters another chemical tank for processing, so as to realize the processing mode of alternately processing the battery piece in the chemical tank and the water tank. In addition, the chemical tank and the water tank of the tank device can be alternately arranged, that is, one chemical tank corresponds to one water tank, and in order to reduce the production and processing cost, a plurality of chemical tanks can also correspond to one water tank, and by setting a reasonable processing time, the time for the battery piece to enter the water tank for cleaning after participating in the reaction in each chemical tank is different, so as to ensure the continuity of the process processing.

[0036] In addition, the tank device refers to a tank as a reactor, the battery piece can be completely immersed in the reactor to react with the tank liquid in the tank, and the battery piece can be switched between different tanks, and the switching mode includes the pulling mode of the mechanical arm. The structure of a single tank in the tank device can be a cylindrical structure, a cuboid, a square, etc., and the structures of the tanks can be the same or different, as long as the purpose of the application can be met, and the application is not limited in particular.

[0037] It can be understood that the tank liquid refers to the solution in the first processing tank and the second processing tank in the tank type reaction device, if the processing tank is a chemical tank, then the tank liquid is a chemical reagent, and if the processing tank is a water tank, then the tank liquid is water. The tank liquid has a certain depth in the first processing tank and the second processing tank, and the tank liquid surface refers to the plane where the highest point of the tank liquid in the depth of the processing tank is located. The lowest point of the battery piece being separated from the tank liquid surface of the first processing tank refers to the lowest point of the battery piece being separated from the plane where the highest point of the tank liquid in the first processing tank is located.

[0038] In order to ensure that the battery piece has a low liquid amount when switching between the first processing tank and the second processing tank, the battery piece is lifted in a segmented manner during the lifting process in the first processing tank, that is, the first segment is lifted at a first speed to make the lowest point of the battery piece completely leave the surface of the tank liquid, and then the second segment is lifted at a second speed to the second processing tank, and the lifting manner is also used in the second processing tank. The first speed of the relatively slow lifting process is controlled, the second speed is a relatively fast lifting stage, the ratio of the first speed of the relatively slow lifting process to the second speed of the relatively fast lifting process is 1:6-1:60, and the first speed to the second speed is an instantaneous acceleration process. Therefore, during the first segment lifting, the relatively slow lifting process makes the tank liquid separate from the battery piece under the action of surface tension, reducing the liquid amount of the battery piece, and the second segment lifting has an instantaneous acceleration stage, making the tank liquid of the battery piece in an over-weight state, and part of the tank liquid falls under the influence of gravity, further reducing the liquid amount of the battery piece, thereby reducing the cross-contamination of the tank liquid of the first processing tank and the second processing tank, reducing the occurrence of side reactions, and being beneficial to reducing the dilution degree of the chemical reagent in the chemical tank and the pollution degree of the water in the water tank, thereby increasing the utilization rate of the chemical reagent and water and reducing the production cost.

[0039] It can be understood that the battery piece is generally placed on a carrier during the processing process in the tank type equipment, and the mechanical arm of the tank type equipment directly acts on the carrier, so as to realize the switching of the battery piece between the chemical tank and the water tank. In this process, the carrier also inevitably carries tank liquid, so the above-mentioned lifting manner can effectively reduce the liquid amount of the carrier, especially when a flower basket is used as the carrier. Due to the reduction of the liquid amount of the flower basket, the flower basket mark existing on the surface of the battery piece during the production process can be effectively reduced, thereby improving the yield of the battery piece.

[0040] Referring to Figure 1 , Figure 1 A schematic diagram of lifting the battery piece in a uniform speed is provided. In this process, the mechanical arm 1 acts on the battery piece 3 immersed in the tank liquid of the first processing tank 2, and then the battery piece 3 is lifted at a uniform speed and lifted into the tank liquid of the second processing tank 4. In this lifting process, the lifting speed is higher than the first speed of the present application, and there is no process of changing speed, so only the action of the surface tension of the tank liquid is used to reduce the liquid amount of the battery piece 3. If the battery piece 3 is in a hydrophilic state, due to the fast lifting speed, the action of the surface tension of the tank liquid is limited and difficult to separate from the surface of the battery piece 3, so the liquid amount of the battery piece 3 is high; referring to Figure 2 , Figure 2is a schematic diagram of the battery piece lifting method provided by the present application. First, the mechanical arm 1 acts on the battery piece 3 immersed in the first processing tank 2, and lifts the battery piece 3 to the lowest point of the battery piece 3 to separate from the surface of the tank liquid of the first processing tank 2 at a first speed. At this stage, part of the tank liquid can fall off the battery piece 3 under the action of surface tension. Then, the battery piece 3 is lifted at a second speed and placed in the tank liquid of the second processing tank 4. During the lifting process, the tank liquid of the battery piece 3 is in an over-weight state under the action of gravity, so that the tank liquid is thrown off the battery piece 3, further reducing the liquid amount of the battery piece 3.

[0041] In addition, when the first speed is 10mm / s-100mm / s and the second speed is 400mm / s-600mm / s, the liquid amount of the battery piece is relatively low. When the first speed and the second speed are within the above range, the lifting speed of the first stage is relatively slow, and the tank liquid of the battery piece is more affected by the surface tension. Especially for the battery piece in the hydrophilic state, the first speed described above still has a high liquid removal amount of the battery piece under the action of the surface tension of the tank liquid. Further setting the lifting speed of the second stage within the above range under the influence of gravity, so that the battery piece has a higher liquid removal amount, and finally the battery piece has a low liquid amount. In addition, the time of the battery piece in the air will not be too long, thereby reducing the pollution of the dust in the air to the battery piece, which is beneficial to improve the yield of the battery piece. Exemplarily, the first speed is 10mm / s, 40mm / s, 60mm / s, 100mm / s, etc., and the second speed is 400mm / s, 440mm / s, 480mm / s, 520mm / s, 580mm / s, 600mm / s, etc.

[0042] After the lowest point of the battery piece separates from the liquid surface, the surface tension of the region where the lowest point is located has a poor effect because the region separates from the liquid surface for a short time, and the battery piece has a high liquid amount. In order to ensure that the region has a low liquid amount, the height H of the lowest point of the battery piece from the surface of the tank liquid after the first lifting step is completed is 5mm-30mm, so that the battery piece has a low liquid amount after the first lifting step, and is conducive to the second lifting stage. If the height is too low, the battery piece is difficult to completely separate from the liquid surface, and if the speed is further increased, it is difficult to effectively reduce the liquid amount of the battery piece. If the height is too high, the lifting time of the battery piece in the first lifting stage is too long, which affects the production efficiency, and because the lifting time of the battery piece in the first lifting stage is too long, the lifting distance of the battery piece in the second lifting stage is short, so that the removal amount of the tank liquid on the battery piece in the second lifting stage is low. Exemplarily, H is 5mm, 9mm, 15mm, 20mm, 25mm, 30mm, etc.

[0043] In the step of segmented pulling, the cell piece is pulled perpendicularly to the surface of the tank solution, i.e. the cell piece is pulled in a manner perpendicular to the surface of the tank solution, so that the area of the cell piece detached from the surface of the tank solution is the same in the same time period. If the pulling is in an inclined manner, the lowest point of the cell piece stays in the tank solution for too long, so that the area of the cell piece participates in the chemical reaction to a higher degree, and the cleaning and etching effects of different areas of the whole cell piece differ greatly, affecting the quality of the cell piece. In addition, if the pulling is in an inclined manner, the first speed and the second speed of the pulling differ greatly, and the uniformity of the force on the cell piece is poor at the moment of speed change, so that the cell piece is prone to falling in the second pulling process, resulting in poor stability of the process.

[0044] When the size of the cell piece is 150mm-210mm, the height of the highest point of the cell piece from the surface of the tank solution is 550mm-580mm after the step of segmented pulling is completed, so as to ensure the continuity of the production process of the cell piece. In addition, the amount of liquid removed from the cell piece is related to the size of the cell piece. The smaller the cell piece, the lower the amount of liquid carried by the cell piece, but it will also affect the photoelectric conversion efficiency of the cell piece. The larger the cell piece, the higher the amount of liquid carried by the cell piece, and the consumption of chemical reagents and water increases, which is not conducive to the efficiency of production and processing, and increases the difficulty of cell piece production. Exemplarily, the size of the cell piece is 150mm, 170mm, 190mm, 210mm, etc. After the segmented pulling is completed, the height of the highest point of the cell piece from the surface of the tank solution is 550mm, 560mm, 570mm, 580mm, etc.

[0045] The processing time of the cell piece in the whole wet process is not only related to the time of the cell piece in the tank process, but also related to the pulling time of the cell piece. Therefore, by reasonably setting the process time and the pulling time, the continuity of production and processing can be ensured. Although the present application adopts the segmented pulling manner, by reasonably setting the first speed and pulling distance of the first segment pulling, and the second speed and pulling distance of the second segment pulling, the whole process time of the wet process differs from the process time of pulling the cell piece in the conventional uniform speed pulling manner by 0-3s, so as to ensure the continuity of the wet process.

[0046] The method of the present application makes the dilution degree of the chemical reagents smaller, so as to help improve the utilization rate of the chemicals and reduce the cost. Specifically, if the tank device is used for texturing process, the concentration of hydrofluoric acid decreases by 40%-60%, the concentration of the additive decreases by 4%-8%, the concentration of sodium hydroxide decreases by 5%-9%, and the concentration of hydrogen peroxide decreases by 10%-16%.

[0047] The reagent replenishment frequency is reduced due to the reduced degree of dilution of the chemical reagents, thereby helping to reduce the consumption of chemicals, increase the utilization rate of chemicals, and reduce the cost of production and processing. In terms of 100,000 battery pieces, the consumption of hydrogen peroxide is reduced by 1.2L / wp-2.5L / wp, the consumption of additives is reduced by 0.05L / wp-0.4L / wp, the consumption of sodium hydroxide is reduced by 0.3L / wp-1.0L / wp, the consumption of hydrofluoric acid is reduced by 0.5L / wp-1.5L / wp, and the consumption of water is reduced by 0.01t / wp-0.1t / wp.

[0048] Specifically, if the unit price of sodium hydroxide is 3 yuan per liter, the unit price of hydrogen peroxide is 2 yuan per liter, the unit price of additives is 8 yuan per liter, and the unit price of hydrofluoric acid is 10 yuan per liter, and the number of battery pieces produced per day is 3.6 million, then the cost of chemical reagents can be reduced by 2,177,000 yuan per year, and the cost of water can be reduced by 39,000 yuan per year, which undoubtedly reduces the cost of the entire production and processing of the etching process to a high degree, and improves the efficiency of battery piece production.

[0049] Further, when the size of the battery piece is 183mm, in the first pulling step, the first speed is 50mm / s, and the height of the lowest point of the battery piece from the surface of the tank liquid is 25mm, in the second pulling step, the second speed is 500mm / s, and the height of the highest point of the battery piece from the surface of the tank liquid is 565mm, at this time, the liquid amount of the battery piece is low.

[0050] Further, the tank device further comprises a slow pulling tank arranged after the first processing tank and the second processing tank, and the lifting speed in the slow pulling tank is 3mm / s-5mm / s. When entering the slow pulling tank, the battery piece is in a hydrophobic state, and the hydrophobic characteristics of the surface of the battery piece are utilized, so that the water residue in the battery piece is reduced at a very slow pulling speed, thereby facilitating the subsequent drying process, reducing the water mark of the battery piece after drying, and improving the yield of the battery piece. If a variable speed is used, the water removal effect under the action of gravity in the fast stage is limited, and it is difficult to achieve the effect of slow speed, thereby affecting the subsequent drying process of the battery piece. Exemplarily, the pulling speed of the slow pulling tank is 3mm / s, 3.5mm / s, 4mm / s, 5mm / s, etc.

[0051] In order to make a more detailed description of the technical solutions and technical effects of the present application, the present application will be further described through more specific examples and performance test results.

[0052] Example 1:

[0053] A groove type device is provided for a texturing process, the groove type device comprising a first processing groove, a second processing groove, wherein the first processing groove is a chemical groove comprising a pre-cleaning groove, a texturing groove, an acid groove, and the second processing groove is a water groove comprising a first water groove, a second water groove, a third water groove, and the processing sequence of the battery piece in the groove type device is pre-cleaning groove, first water groove, texturing groove, second water groove, acid groove, third water groove, slow pulling groove, and drying groove.

[0054] The battery piece immersed in the pre-cleaning groove in a vertical state is segmented and pulled upward in the vertical direction; the segmented pulling comprises a first segment pulling and a second segment pulling, the first segment pulling pulls the battery piece at a first speed of 50 mm / s, until the lowest point of the battery piece is 25 mm away from the height of the liquid surface of the first processing groove, and the second segment pulling continues to pull the battery piece at a second speed of 500 mm / s, until the highest point of the battery piece is 565 mm away from the height of the liquid surface.

[0055] The pulled battery piece is placed into the first water groove; the ratio of the first speed to the second speed is 1:10, and the battery piece is perpendicular to the liquid surface;

[0056] The subsequent process of the battery piece pulled out from the first water groove is in sequence of the texturing groove, the second water groove, the acid groove, and the third water groove, and the above grooves are all pulled by the segmented pulling method;

[0057] The battery piece pulled out from the third water groove is placed into the slow pulling groove, and the pulling speed of the battery piece in the slow pulling groove is 4 mm / s, and the pulled battery piece is placed into the drying groove for drying to complete the texturing process of the battery piece.

[0058] Example two:

[0059] The difference between this example and example one is that the first speed is 50 mm / s, and the second speed is 300 mm / s, i.e. the ratio of the first speed to the second speed is 1:6.

[0060] Example three:

[0061] The difference between this example and example one is that the first speed is 10 mm / s, and the second speed is 600 mm / s, i.e. the ratio of the first speed to the second speed is 1:60.

[0062] Example four:

[0063] The difference between this example and example one is that the first speed is 20 mm / s, and the second speed is 400 mm / s, i.e. the ratio of the first speed to the second speed is 1:20.

[0064] Example five:

[0065] The difference between this embodiment and embodiment one is that the first speed is 5 mm / s and the second speed is 300 mm / s.

[0066] Embodiment six:

[0067] The difference between this embodiment and embodiment one is that the first speed is 50 mm / s and the second speed is 700 mm / s.

[0068] Embodiment seven:

[0069] The difference between this embodiment and embodiment one is that after the first pulling step, the height H of the lowest point of the battery piece from the surface of the tank liquid is 5 mm.

[0070] Embodiment eight:

[0071] The difference between this embodiment and embodiment one is that after the first pulling step, the height H of the lowest point of the battery piece from the surface of the tank liquid is 30 mm.

[0072] Embodiment nine:

[0073] The difference between this embodiment and embodiment one is that after the first pulling step, the height H of the lowest point of the battery piece from the surface of the tank liquid is 40 mm.

[0074] Embodiment ten:

[0075] The difference between this embodiment and embodiment one is that the battery piece is pulled in an inclined manner.

[0076] Comparative example one:

[0077] The difference between this comparative example and embodiment one is that the first speed is 100 mm / s and the second speed is 400 mm / s, i.e., the ratio of the first speed to the second speed is 1:4.

[0078] Comparative example two:

[0079] The difference between this comparative example and embodiment one is that the first speed and the second speed are both 400 mm / s, i.e., the ratio of the first speed to the second speed is 1:1.

[0080] Comparative example three:

[0081] The difference between this comparative example and embodiment one is that the first speed is 10 mm / s and the second speed is 700 mm / s, i.e., the ratio of the first speed to the second speed is 1:70.

[0082] Test result one:

[0083] The amount of chemical reagent and water reduced in embodiments one to ten and comparative examples one to three was tested:

[0084]

[0085] From the data of Examples 1-10 and Comparative Examples 1-3, the reduced amount of chemical reagents and water in the examples is higher than that in Comparative Examples 1-2, indicating that the pulling method of the present application can effectively reduce the use cost of chemical reagents and water in the wet process, thereby increasing the benefit of producing battery pieces; since the first and second speeds of Comparative Example 3 are relatively high, the loss of the tank equipment is high, and the motor loss is large, which undoubtedly increases the maintenance and modification cost of the equipment.

[0086] From the data of Examples 1-6, the data of Examples 1-4 is better than that of Examples 5 and 6, because the first speed of Examples 1-4 is in the range of 10-100 mm / s, and the second speed is in the range of 400-600 mm / s, so the first-stage pulling makes the tank solution of the battery piece separate from the surface to a high degree under the action of surface tension, and the second speed in the above range is low, and the above speed range also does not adversely affect the production and processing of the battery piece.

[0087] From the data of Examples 1, 7 and 8, the data of Example 8 is the best, because the height H of the lowest point of the battery piece from the surface of the tank solution in Example 8 is high, so that when the battery piece falls off the surface of the tank solution, the pulling time of the lowest point in the first-stage pulling is long, so the effect of the surface tension of the tank solution is high, and the dehydration degree in the first-stage pulling is high, thereby making the data of Example 8 better; from the data of Examples 8 and 9, the data of Example 8 is better than that of Example 9, because the height H of the lowest point of the battery piece from the surface of the tank solution in Example 8 is low, so on the one hand the surface tension effect of the tank solution in the first-stage pulling is good, and on the other hand the effect of the tank solution falling off the battery piece under the action of gravity in the second-stage pulling is not obvious due to the short pulling distance, so the liquid carrying degree of the battery piece is low.

[0088] From the data of Examples 1 and 10, the data of Examples 1 and 10 is similar, but the inclined pulling method of Example 10 leads to poor stability of the battery piece during pulling, which affects the processing efficiency of the battery piece, and the time for the lowest point of the battery piece to separate from the tank solution is long, so the etching uniformity is worse, which affects the quality of the battery piece.

[0089] The pulling method of the battery piece disclosed in the embodiments of the present application is described in detail above, and the principles and implementation manners of the present application are described by using specific examples. The above embodiment description is only used to help understand the pulling method of the battery piece. Meanwhile, for those skilled in the art, according to the idea of the present application, the specific implementation manners and application ranges will be changed, and the above description should not be understood as a limitation on the present application.

Claims

1. A method for lifting a battery cell, characterized in that, The lifting method includes: A trough-type device is provided, the trough-type device comprising a plurality of first processing troughs and a plurality of second processing troughs, wherein the battery cells are alternately immersed in the first processing troughs and the second processing troughs; The battery cell, which is vertically immersed in the first processing tank, is lifted upward in segments along the vertical direction. The segmented lifting includes a first segment lifting and a second segment lifting. The first segment lifting lifts the battery cell at a first speed until the lowest point of the battery cell leaves the surface of the liquid in the first processing tank. The second segment lifting continues to lift the battery cell at a second speed. The lifted battery cell is placed into the second processing tank; wherein, one of the first processing tank and the second processing tank is a chemical tank and the other is a water tank, and the ratio of the first speed to the second speed is 1:6 to 1:

60.

2. The lifting method according to claim 1, characterized in that, The first velocity is 10 mm / s to 100 mm / s, and the second velocity is 400 mm / s to 600 mm / s.

3. The lifting method according to claim 1, characterized in that, After the first lifting step is completed, the height H of the lowest point of the battery cell from the surface of the bath liquid is 5mm to 30mm.

4. The lifting method according to claim 1, characterized in that, During the segmented lifting step, the battery cell is perpendicular to the surface of the bath liquid.

5. The method according to claim 1, characterized in that, The size of the battery cell is 150mm to 210mm.

6. The method according to claim 5, characterized in that, After the segmented lifting step is completed, the height of the highest point of the battery cell from the surface of the bath liquid is 550mm to 580mm.

7. The method according to claim 1, characterized in that, The tank-type equipment is used for the texturing process. The solution in the chemical tank includes chemical reagents. Based on the mass concentration of the chemical reagents, the concentration of hydrofluoric acid decreases by 40% to 60%, the concentration of additives decreases by 4% to 8%, the concentration of sodium hydroxide decreases by 5% to 9%, and the concentration of hydrogen peroxide decreases by 10% to 16%.

8. The method according to claim 7, characterized in that, Based on 10,000 of the aforementioned battery cells, the consumption of hydrogen peroxide decreases by 1.2 L / wp to 2.5 L / wp, the consumption of additives decreases by 0.05 L / wp to 0.4 L / wp, the consumption of sodium hydroxide decreases by 0.3 L / wp to 1.0 L / wp, the consumption of hydrofluoric acid decreases by 0.5 L / wp to 1.5 L / wp, and the consumption of water decreases by 0.01 t / wp to 0.1 t / wp.

9. The method according to claim 1, characterized in that, The battery cell has a size of 183mm. In the first lifting step, the first speed is 50mm / s, and the lowest point of the battery cell is 25mm above the surface of the bath liquid. In the second lifting step, the second speed is 500mm / s, and the highest point of the battery cell is 565mm above the surface of the bath liquid.

10. The method according to claim 1, characterized in that, The trough-type equipment also includes a slow lifting trough located after the first processing trough and the second processing trough, wherein the lifting speed of the slow lifting trough is 3mm / s to 5mm / s.

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