Ultrathin high-performance 8-micron double-sided photocell aluminum foil and preparation method thereof

Abstract

The invention discloses an ultrathin high-performance 8 [mu] m double-sided photocell aluminum foil and a preparation method thereof. The thickness of the prepared battery aluminum foil is 8 micrometers, the strength is larger than or equal to 280 MPa, the ductility is larger than or equal to 3.5%, the mass per unit area is 21.02-22.33 g / m < 2 >, and the dyne value is larger than or equal to 35 Dyne / cm. The battery aluminum foil comprises the following alloy chemical components in percentage by mass: 0.110 to 0.145 percent of Si, 0.400 to 0.445 percent of Fe, 0.150 to 0.180 percent of Cu, 0.020 to 0.040 percent of Mn, less than or equal to 0.01 percent of Mg, less than or equal to 0.1 percent of Zn, less than or equal to 0.03 percent of Ti and the balance of Al and inevitable impurity elements. The Al content is greater than or equal to 99.2%. The battery aluminum foil is prepared through smelting, refining, filtering, cast rolling, cold rolling, rolling, primary slitting, primary corona and fine cutting in sequence. The double-light battery aluminum foil with the strength larger than or equal to 280 MPa and the elongation larger than or equal to 3.5% is prepared through the method, and it can be guaranteed that the phenomena of rolling belt breaking in the rolling process and aluminum foil bending and breaking in the winding process can be reduced.

Description

I. TECHNICAL FIELD

[0001] The application belongs to the technical field of battery foil preparation, and particularly relates to an ultrathin high-performance 8-micron double-sided photoelectric battery aluminum foil and a preparation method thereof. II. BACKGROUND

[0002] Small power batteries mainly provide power systems for various sub-products, and the main feature is to replace the original power systems, such as lead-acid, nickel-hydrogen, etc. The small power field of lithium batteries mainly includes electric bicycles, electric forklifts, AGV vehicles, low-speed vehicles, etc. With the decrease of the cost of lithium ion batteries and the continuous improvement of technology, it is beneficial to reduce the weight of electric light vehicles and improve the cycle life of the battery.

[0003] At present, the small power mainly uses 12-micron and 10-micron power battery foils, and the head digital 3C battery enterprises have maturely applied 9-micron power battery foils in mobile phone batteries, unmanned aerial vehicle lithium batteries and other products, thereby increasing the capacity in a limited battery volume to improve the endurance capability. At present, the thinnest copper foil 4.5 microns has reached the processing limit, and the aluminum foil theory can also reach 4.5 microns, but the thinnest aluminum foil produced by the battery foil manufacturer is 9 microns, which has a large thinning space.

[0004] The common methods for improving the capacity of the battery per unit area at present are: one is to continue to reduce the thickness of the battery foil, and the other is to improve the coating of the positive and negative electrode paste. From the current technical development, it is relatively reliable to reduce the thickness of the aluminum foil, and some head digital 3C battery enterprises have started the 8-micron double photoelectric battery foil project to improve the battery capacity. III. SUMMARY

[0005] The technical problem to be solved by the present application is that according to the current common method for improving the capacity of the battery per unit area, the present application provides an ultrathin high-performance 8-micron double-sided photoelectric battery aluminum foil and a preparation method thereof. The technical scheme of the present application can prepare an 8-micron double-sided photoelectric battery aluminum foil with a strength of ≥280 MPa, an elongation of ≥3.5%, a unit area mass of 21.02-22.33 g / m 2 , and a dyne value of ≥35 Dyne / cm.

[0006] In order to solve the above problems, the technical scheme adopted by the present application is:

[0007] The present application provides an ultrathin high-performance 8-micron double-sided photoelectric battery aluminum foil, wherein the thickness of the ultrathin high-performance 8-micron double-sided photoelectric battery aluminum foil is 8 microns, the strength is ≥280 MPa, the elongation is ≥3.5%, the unit area mass is 21.02-22.33 g / m 2 , and the dyne value is ≥35 Dyne / cm.

[0008] According to the above-mentioned ultra-thin high-performance 8μm double-sided photocell aluminum foil, the chemical composition and mass percentage of each alloy in the ultra-thin high-performance 8μm double-sided photocell aluminum foil are as follows: Si 0.110-0.145%, Fe 0.400-0.445%, Cu 0.150-0.180%, Mn 0.020-0.040%, Mg≤0.01%, Zn≤0.1%, Ti≤0.03%, and the balance is Al and inevitable impurity elements; and the Al≥99.2%.

[0009] In addition, a preparation method of an ultra-thin high-performance 8μm double-sided photocell aluminum foil is provided, and the preparation method comprises the following steps:

[0010] a. Melting: pure aluminum ingots are added to a melting furnace for melting, and after melting, component adjustment is performed according to the content requirements of each alloy chemical composition in the ultra-thin high-performance 8μm double-sided photocell aluminum foil, so that the alloy liquid obtained by melting meets the content requirements of each alloy chemical composition in the above-mentioned battery aluminum foil;

[0011] b. Refining: the alloy liquid obtained in step a is refined, and three times of slagging is performed during the refining process, and the hydrogen content is ≤0.08ml / 100g Al;

[0012] c. Filtration: the alloy liquid obtained after slagging is subjected to double filtration by using a plate-type filter box and a pipe-type filter box (after double filtration, metal and non-metallic inclusions can be effectively filtered, and the filtration precision is ensured);

[0013] d. Casting and rolling: the aluminum liquid obtained after filtration is flowed into a forebox and a casting nozzle, and is cast and rolled into a cold-rolled blank by a casting and rolling roller (with cooling water) ;

[0014] e. Cold rolling: the cold-rolled blank obtained by casting and rolling is cold-rolled for six passes to obtain an aluminum foil blank with a thickness of 0.20mm;

[0015] f. Rolling: the obtained aluminum foil blank is subjected to two rough rolling passes of the first pass and the second pass in sequence to obtain an aluminum foil with a thickness of 30μm; then one annealing is performed, and after annealing, one finish rolling is performed to obtain an aluminum foil with a thickness of 13.8μm, and then a second finish rolling is performed to obtain an aluminum foil roll with a thickness of 8μm;

[0016] g. Slitting: the obtained 8μm aluminum foil roll after rolling is subjected to one slitting;

[0017] h. Corona treatment: the roll obtained after one slitting is subjected to one corona treatment;

[0018] I. Fine cutting: fine cutting is performed according to requirements, and the finished product after fine cutting is packaged.

[0019] According to the preparation method of the super-thin high-performance 8μm double-sided photocell aluminum foil, the temperature is controlled to be 720-760℃ during the melting in step a (pure aluminum ingot is used as the raw material, so as to reduce the formation of pinholes) ;

[0020] During the refining in step b, the refining temperature is controlled to be 750-780℃; pure argon is used for the refining, the argon flow is 8-12m 2 / h, the bubbling height during the refining in the holding furnace is ≤ 250mm, the refining frequency is 3 times, the refining time of each time is 20-30min; the bubbling height during the refining in the holding furnace is ≤ 180mm, the refining frequency is 2-3 times.

[0021] During the casting and rolling in step d of the preparation method of the super-thin high-performance 8μm double-sided photocell aluminum foil, the casting and rolling speed is 750-850mm / min, the length of the casting and rolling zone is 58-64mm, the rolling force is 3500-4000KN, and the outlet temperature of the holding furnace is 730±5℃; the thickness of the obtained cold-rolled blank is 6.5-7mm.

[0022] The reduction of the six passes of cold rolling in step e of the preparation method of the super-thin high-performance 8μm double-sided photocell aluminum foil is 6.5-3.8-2.0-1.2-0.65-0.34-0.20mm; after rolling 3.8mm, O-state annealing is carried out once, the annealing temperature is 550±30℃, and the annealing time is 6+15h.

[0023] The reduction of the two passes of rough rolling in step f of the preparation method of the super-thin high-performance 8μm double-sided photocell aluminum foil is 200-80-30μm; the rolling force of the first pass of rough rolling is 2000-2500KN, the rolling speed is 650-850m / min, the unwinding tension is 25-55N / mm 2 , the oil temperature is 28-35℃; the rolling force of the second pass of rough rolling is 2100-2600KN, the rolling speed is 900-1200m / min, the unwinding tension is 25-60N / mm 2 , the oil temperature is 25-35℃; the rolling oil conditions are as follows: the viscosity is 2.0-2.3Cst, the content of additive 1 is 5.5-8.5%, the content of additive 2 is 6.0-8.0%, and the content of additive 3 is 0.30-0.40%; the roughness Ra of the rough rolling roller is 0.15-0.18, the convexity is 30μm, and the roller diameter is 270-280mm;

[0024] During the annealing in step f, the annealing temperature is 210±10℃, and the holding time is 12-16h.

[0025] According to the preparation method of the super-thin high-performance 8-micron double-sided photocell aluminum foil, the reduction of the two times of finish rolling in step f is 30-13.8-8 microns; the rolling force of the first pass finish rolling is 2300-3500 KN, the rolling speed is 850-1150 m / min, and the unwinding tension is 30-85 N / mm 2 , the oil temperature is 30-35 DEG C; the rolling force of the second pass finish rolling is 3000-4500 KN, the rolling speed is 600-850 m / min, and the unwinding tension is 45-85 N / mm 2 , the oil temperature is 40-48 DEG C; the rolling oil conditions are that the viscosity is 1.90-2.0 cst, the content of additive 1 is 5.0-7.0%, the content of additive 2 is 1.0-3.5%, and the content of additive 3 is 0-0.1%; the roughness Ra of the finish rolling roller is 0.06-0.08, the crown is 50 microns, and the roller diameter is 240+ / -0.5 mm.

[0026] According to the preparation method of the super-thin high-performance 8-micron double-sided photocell aluminum foil, the additive 1 is a mixture of C10-16 mixed primary alcohol and methyl dodecanoate, and the mixing mass ratio between the C10-16 mixed primary alcohol and methyl dodecanoate is 1:6-8; the additive 2 is C10-16 mixed primary alcohol; and the additive 3 is lauric acid, and the acid value content of the lauric acid is 280 mg KOH / g.

[0027] According to the preparation method of the super-thin high-performance 8-micron double-sided photocell aluminum foil, the once cutting in step g adopts a Compton cutting machine, and the control once cutting speed is 350-550 m / min; in the corona process in step h, a 1700 mm wide corona machine (the model is Bole Sida) is adopted, the control corona speed is 100-150 m / min, the corona power is 80-120 KW, and the corona frequency is 1 time; in the trimming in step I, a Wan Ying aluminum foil cutting machine is adopted, and the cutting speed is 180-220 m / min.

[0028] In the preparation method of the super-thin high-performance 8-micron double-sided photocell aluminum foil, when the 8-micron aluminum foil roll obtained after rolling is once cut, a hot air knife device is added to the cutting machine, the air knife temperature is controlled to be 60-70 DEG C, which is beneficial to volatilization during the once cutting process, further reduces the surface residue, and lays a foundation for improving the dino value in the corona process.

[0029] In the preparation method of the ultra-thin high-performance 8-micron double-sided photocell aluminum foil of the application, the obtained material roll is subjected to once corona treatment, the corona machine used is kept at constant temperature to ensure that the temperature of the ceramic electrode area is increased, which is beneficial to the volatilization of the oil film on the surface of the material, the temperature is set to 55-75 DEG C, and a wind knife is additionally installed on the four ceramic electrode pipes, the temperature of the wind knife is controlled to 60-70 DEG C, and the oil removal rate of the corona treatment is increased by 20 percentage points compared with the original, and the dynes value can be increased to 40 dyn / cm after once corona treatment.

[0030] The positive beneficial effects of the application are as follows:

[0031] 1. The foil rolling of the technical scheme adopts 4 passes of rolling (2 times of rough rolling and 2 times of finish rolling), which reduces one pass compared with the 9-micron double photocell aluminum foil, wherein the reduction of the second rough rolling reaches 62.5%, which has reached the maximum reduction of the battery foil rolling; one pass is reduced, so that the production efficiency of the whole production process is increased by more than 40%.

[0032] 2. In order to ensure 4 passes of rolling, the technical scheme introduces the rough rolling post-annealing mode to reduce the strength of 20-35 MPa, reduce the rolling parameters, and optimize the rolling process. The traditional intermediate rolling process is omitted, and the finish rolling is directly used to reduce the roughness of the three passes of rolling to ensure that the rolling can be stably carried out.

[0033] 3. The technical scheme uses low roughness rollers from the rough rolling, the rough rolling roller Ra is 0.15-0.18, and the finish rolling roller Ra is 0.06-0.08. Compared with the existing process, the roughness of the rollers of each pass is greatly reduced. The lower the roughness of the roller, the higher the cleanliness of the aluminum foil surface, and the more conducive to the volatilization of the residual oil on the surface.

[0034] 4. In the technical scheme, the finished product roller adopts small roller diameter rolling (finish rolling process), reduces the bite angle of the rolling deformation zone, is beneficial to the rolling of the ultra-thin material, and controls the plate shape.

[0035] 5. The double photocell aluminum foil with the performance of strength ≥280 MPa and elongation rate ≥3.5% is prepared by using the technical scheme, which ensures that the rolling breakage is reduced in the rolling process, and the aluminum foil bending and fracture phenomenon is reduced in the winding process.

[0036] 6. In the technical scheme, after the finished product rolling, due to the low viscosity of the rolling oil, the speed of the first slitting is controlled, a hot air knife device is additionally installed on the slitting machine, the temperature of the air knife is controlled to 60-70 DEG C, which is beneficial to the volatilization during the first slitting process, further reduces the surface residue, and improves the dynes value for the corona process.

[0037] 7. The corona machine used in the technical solution of the present invention maintains a constant temperature of the corona roller to ensure that the temperature of the ceramic electrode area is increased, which is conducive to the volatilization of the oil film on the material surface. The temperature is set at 55-75°C, and air knives are installed on the four ceramic electrode tubes. The air knife temperature is controlled at 60-70°C. After testing, its corona oil removal rate is increased by 20 percentage points compared with the original. After one corona, the dyne value can be increased to 40dyn / cm. 4. Specific implementation methods:

[0038] The present invention is further described below with reference to the following examples, but the scope of protection of the technical solution of the present invention is not limited thereto.

[0039] Additive 1 used in the following examples is a mixture of C10-16 mixed primary alcohols and methyl dodecanoate, with the mixing mass ratio of the C10-16 mixed primary alcohols and methyl dodecanoate being 1:8; Additive 2 is C10-16 mixed primary alcohols; and Additive 3 is lauric acid, with an acid value of 280 mg KOH / g.

[0040] Example 1:

[0041] The ultra-thin, high-performance 8μm double-sided photovoltaic cell aluminum foil of the present invention has a thickness of 8μm, a tensile strength of 285MPa, an elongation of 3.84%, and a unit area mass of 21.92g / m 2 , dyne value is 40Dyne / cm.

[0042] Example 2:

[0043] The method for preparing the ultra-thin, high-performance 8μm double-sided photovoltaic cell aluminum foil described in Example 1 of the present invention has the following detailed steps:

[0044] a. Melting: Pure aluminum ingots are added to a melting furnace for melting at a temperature of 730-740°C (pure aluminum ingots are used as raw materials to reduce pinhole formation); after melting, the composition is adjusted according to the content requirements of the chemical components of each alloy in the ultra-thin, high-performance 8μm double-sided photovoltaic cell aluminum foil, so that the resulting alloy liquid meets the content requirements of the chemical components of each alloy in the battery aluminum foil (Si 0.127%, Fe 0.434%, Cu 0.161%, Mn 0.031%, Mg 0.0007%, Zn 0.009%, Ti 0.015%, and the balance is Al);

[0045] b. Refining: Refining the alloy liquid obtained in step a, performing three slag removals during the refining process, and the hydrogen content is ≤0.08ml / 100gAl;

[0046] During the refining, the refining temperature is controlled at 750-760°C; pure argon is used for refining, and the argon flow rate is 10m 2h, the foaming height during refining is less than or equal to 250 mm, the refining frequency is 3 times, and the refining time is 22 min each time; the foaming height during holding furnace refining is less than or equal to 180 mm, and the refining frequency is 3 times;

[0047] c. filtering: the alloy liquid obtained after slagging is subjected to double filtering by using a plate filter box and a pipe filter box (after double filtering, metal and non-metallic inclusions can be effectively filtered, and the filtering precision is ensured);

[0048] d. casting and rolling: the aluminum liquid obtained after filtering is flowed into a forebox and a casting nozzle, and is cast and rolled into a cold-rolled blank by a casting and rolling roller (with cooling water) ;

[0049] In the casting and rolling process, the casting and rolling speed is 780 mm / min, the length of the casting and rolling zone is 60 mm, the rolling force is 3600 KN, and the outlet temperature of the holding furnace is 730±5℃; the thickness of the obtained cold-rolled blank is 6.5 mm;

[0050] e. cold rolling: the cold-rolled blank obtained by casting and rolling is cold-rolled by six passes to obtain an aluminum foil blank with a thickness of 0.20 mm; the obtained aluminum foil blank has a specification of 0.20×1210 mm, an alloy state of 1235D / H18, a tensile strength of 200 MPa, and an elongation of 2.8%;

[0051] The reduction amount of the six-pass cold rolling is 6.5-3.8-2.0-1.2-0.65-0.34-0.20 mm; after rolling by 3.8 mm, O-state annealing is carried out once, the annealing temperature is 550±30℃, and the annealing time is 6+15 h;

[0052] f. rolling: the obtained aluminum foil blank is subjected to two rough rolling passes in sequence, i.e. a first pass and a second pass, to obtain an aluminum foil with a thickness of 30 μm, and the rough rolling pass distribution is 200-80-30 μm; then, one annealing is carried out, after annealing, one finish rolling is carried out to obtain an aluminum foil with a thickness of 13.8 μm, and then, second finish rolling is carried out to obtain an aluminum foil roll with a thickness of 8 μm;

[0053] In the rough rolling process, the rolling force of the first pass is 2150 KN, and the rolling force of the second pass is 2300 KN; the rolling speed of the first pass is 750 m / min, and the rolling speed of the second pass is 1000 m / min; the unwinding tension of the first pass is 28 N / mm 2 , and the unwinding tension of the second pass is 32 N / mm 2; the oil temperature of the first pass is 30 DEG C, the oil temperature of the second pass is 30 DEG C, the rolling oil conditions of the first pass and the second pass of rough rolling are as follows: the rough rolling viscosity is 2.25cst, the content of additive 1 is 7.1%, the content of additive 2 is 7.5%, and the content of additive 3 is 0.35%; the rough rolling roller Ra is 0.16, the crown is 30 microns, and the roller diameter is 279.987mm / 279.986mm during rough rolling;

[0054] During annealing, the annealing temperature is controlled to be 210 DEG C, and the holding time is 12 hours;

[0055] During finishing rolling, the reduction of the two times of finishing rolling is 30-13.8-8 microns; the first pass finishing rolling rolling force is 2850KN, the rolling speed is 1100m / min, the opening tension is 35N / mm 2 , the oil temperature is 32 DEG C; the second pass finishing rolling rolling force is 3800KN, the rolling speed is 720m / min, the opening tension is 55N / mm 2 , the oil temperature is 42 DEG C; the rolling oil conditions are as follows: the viscosity is 1.92cst, the content of additive 1 is 6.2%, the content of additive 2 is 1.5%, and the content of additive 3 is 0.05%; the roughness Ra of the finishing rolling roller is 0.07, the crown is 50 microns, and the roller diameter is 239.995 / 239.995mm.

[0056] g, slitting: the 8 micron aluminum foil roll obtained after rolling is subjected to one-time slitting by using a Compton slitting machine, and the one-time slitting speed is controlled to be 500m / min;

[0057] h, corona: the roll obtained after one-time slitting is subjected to one-time corona by using a 1700mm wide corona machine (the model is Bole Sida), the corona speed is controlled to be 150m / min, the corona power is 108KW, and the corona times is 1;

[0058] I, finishing cutting: according to requirements, the finishing cutting is carried out by using a Wanying aluminum foil slitting machine, and the finishing cutting speed is 180m / min, and the finished product after finishing cutting is packaged.

[0059] After detection, the unit area mass of the battery aluminum foil prepared in the embodiment is 21.92g / m 2 , the tensile strength is 285MPa, the elongation is 3.84%, and the surface dyne value is 40dyn / cm.

[0060] Example 3:

[0061] The ultra-thin high-performance 8 micron double-sided photoelectric battery aluminum foil has a thickness of 8 microns, a tensile strength of 288MPa, an elongation of 3.72%, a unit area mass of 22.14g / m 2 , and a dyne value of 42Dyne / cm.

[0062] Example 4:

[0063] The preparation method of the ultra-thin high-performance 8μm double-sided photocell aluminum foil according to the embodiment 3 of the present application has the following detailed steps:

[0064] a. Melting: pure aluminum ingot is added into a melting furnace for melting, and the melting temperature is 750-760℃ (pure aluminum ingot is used as raw material, so as to reduce the formation of pinholes); after melting, the composition is adjusted according to the content requirements of each alloy chemical component in the ultra-thin high-performance 8μm double-sided photocell aluminum foil, so that the alloy liquid obtained by melting meets the content requirements of each alloy chemical component in the battery aluminum foil (Si 0.127%, Fe 0.419%, Cu 0.162%, Mn 0.028%, Mg 0.0009%, Zn 0.008%, Ti 0.012%, and the balance is Al);

[0065] b. Refining: the alloy liquid obtained in step a is refined, and three times of slagging is performed during the refining process, and the hydrogen content is ≤0.08ml / 100g Al;

[0066] During the refining, the refining temperature is controlled to be 750-760℃; pure argon gas is used for refining, and the argon gas flow is 9m 2 / h, the bubbling height during the refining period is ≤250mm, and the refining frequency is 3 times, and the refining time of each time is 25min; the bubbling height during the refining period in the holding furnace is ≤180mm, and the refining frequency is 3 times;

[0067] c. Filtration: the alloy liquid obtained after slagging is subjected to double filtration by using a plate-type filter box and a pipe-type filter box (after double filtration, metal and non-metallic inclusions can be effectively filtered, so as to ensure the filtration precision);

[0068] d. Casting and rolling: the aluminum liquid obtained after filtration is flowed into a front box and a casting nozzle, and is cast and rolled into a cold rolling blank by a casting and rolling roller (with cooling water inside);

[0069] During the casting and rolling process, the casting and rolling speed is 800mm / min, the length of the casting and rolling zone is 62mm, the rolling force is 3800KN, and the outlet temperature of the holding furnace is 730±5℃; the thickness of the obtained cold rolling blank is 6.5mm;

[0070] e. Cold rolling: the cold rolling blank obtained by casting and rolling is cold rolled for six passes to obtain an aluminum foil blank with a finished thickness of 0.20mm; the obtained aluminum foil blank has a specification of 0.20×1210mm, an alloy state of 1235D / H18, a tensile strength of 205MPa, and an elongation of 3.0%;

[0071] The reduction of the six passes of cold rolling is 6.5-3.8-2.0-1.2-0.65-0.34-0.20mm; wherein after rolling 3.8mm, one O-state annealing is carried out, the annealing temperature is 550±30℃, and the annealing time is 6+15h;

[0072] f. rolling: the obtained aluminum foil blank is subjected to first pass and second pass of rough rolling in sequence to obtain aluminum foil with thickness of 30μm, the rough rolling pass distribution is 200-80-30μm; then one annealing is carried out, after annealing, one finish rolling is carried out to obtain aluminum foil with thickness of 13.8μm, and then second finish rolling is carried out to obtain aluminum foil roll with thickness of 8μm;

[0073] In the rough rolling process, the rolling force of the first pass is 2250KN, the rolling force of the second pass is 2400KN; the rolling speed of the first pass is 750m / min, the rolling speed of the second pass is 1050m / min; the uncoiling tension of the first pass is 29N / mm 2 , the uncoiling tension of the second pass is 31N / mm 2 ; the oil temperature of the first pass is 30℃, the oil temperature of the second pass is 30℃, the rolling oil conditions of the first pass and the second pass of rough rolling are: the rough rolling viscosity is 2.25cst, the content of additive 1 is 7.3%, the content of additive 2 is 7.8%, and the content of additive 3 is 0.38%; the rough rolling roller Ra is 0.16, the crown is 30μm, and the roller diameter is 279.992mm / 279.991mm;

[0074] In the annealing process, the annealing temperature is controlled to be 210℃, and the holding time is 14h;

[0075] In the finish rolling process, the reduction of the two finish rolling is 30-13.8-8μm; the rolling force of the first pass of finish rolling is 2800KN, the rolling speed is 1150m / min, the uncoiling tension is 45N / mm 2 , and the oil temperature is 33℃; the rolling force of the second pass of finish rolling is 3750KN, the rolling speed is 735m / min, the uncoiling tension is 52N / mm 2 , and the oil temperature is 43℃; the rolling oil conditions are: the viscosity is 1.95cst, the content of additive 1 is 6.5%, the content of additive 2 is 1.8%, and the content of additive 3 is 0.05%; the roughness Ra of the finish rolling roller is 0.07, the crown is 50μm, and the roller diameter is 239.996 / 239.995mm;

[0076] g. slitting: the obtained 8μm aluminum foil roll after rolling is subjected to one slitting by using a Compton slitting machine, and the slitting speed is controlled to be 550m / min;

[0077] h. Corona: the roll obtained after the first slitting is subjected to one corona treatment by using a 1700mm wide corona machine (the model of which is Bopla), the control corona speed is 150m / min, the corona power is 110KW, and the corona frequency is 1 time;

[0078] I. Fine cutting: according to the requirements, fine cutting is carried out by using Wan Yin aluminum foil slitting machine, the fine cutting speed is 180m / min, and the finished product after fine cutting is packaged.

[0079] After detection, the unit area mass of the battery aluminum foil prepared in the embodiment is 22.14g / m 2 , the tensile strength is 288MPa, the elongation is 3.72%, and the surface dyne value is 42dyn / cm.

[0080] Example 5:

[0081] The ultra-thin high-performance 8μm double-sided photocell aluminum foil of the application has a thickness of 8μm, a tensile strength of 289MPa, an elongation of 3.86%, a unit area mass of 22.19g / m 2 , and a dyne value of 42Dyne / cm.

[0082] Example 6:

[0083] The preparation method of the ultra-thin high-performance 8μm double-sided photocell aluminum foil described in the embodiment 5 of the application has the following detailed steps:

[0084] a. Melting: pure aluminum ingot is added to a melting furnace for melting, and the melting temperature is 735-745℃ (pure aluminum ingot is used as raw material, in order to reduce the formation of pinholes); after melting, the composition is adjusted according to the content requirements of each alloy chemical component in the ultra-thin high-performance 8μm double-sided photocell aluminum foil, so that the alloy liquid obtained by melting meets the content requirements of each alloy chemical component in the battery aluminum foil (Si 0.126%, Fe 0.414%, Cu 0.161%, Mn 0.025%, Mg 0.0007%, Zn 0.006%, Ti 0.013%, and the balance is Al);

[0085] b. Refining: the alloy liquid obtained in step a is refined, and three times of slagging is carried out during the refining process, and the hydrogen content is ≤0.08ml / 100gAl;

[0086] During the refining, the refining temperature is controlled to be 750-760℃; pure argon is used for refining, the argon flow is 11m 2 / h, the foaming height during the refining period is ≤250mm, and the refining frequency is 3 times, and the refining time of each time is 22min; the foaming height during the refining period in the holding furnace is ≤180mm, and the refining frequency is 3 times;

[0087] c. filtering: the alloy liquid obtained after slagging is filtered by a plate filter box and a pipe filter box (after double filtration, metal and non-metallic inclusions can be effectively filtered, and the filtering precision is ensured);

[0088] d. casting and rolling: the filtered aluminum liquid is flowed into a former and a casting nozzle, and is cast and rolled into a cold-rolled blank by a casting and rolling roller (with cooling water) ;

[0089] In the casting and rolling process, the casting and rolling speed is 780 mm / min, the length of the casting and rolling area is 60 mm, the rolling force is 3600 KN, and the outlet temperature of the holding furnace is 730±5℃; the thickness of the obtained cold-rolled blank is 6.5 mm;

[0090] e. cold rolling: the cold-rolled blank obtained by casting and rolling is cold-rolled for six passes to obtain an aluminum foil blank with a thickness of 0.20 mm; the obtained aluminum foil blank has a specification of 0.20×1210 mm, an alloy state of 1235D / H18, a tensile strength of 203 MPa, and an elongation of 3.2%;

[0091] The reduction of the six-pass cold rolling is 6.5-3.8-2.0-1.2-0.65-0.34-0.20 mm; after rolling by 3.8 mm, O-state annealing is carried out once, the annealing temperature is 550±30℃, and the annealing time is 6+15 h;

[0092] f. rolling: the obtained aluminum foil blank is sequentially subjected to first-pass and second-pass rough rolling to obtain an aluminum foil with a thickness of 30 μm, and the rough rolling pass distribution is 200-80-30 μm; then, annealing is carried out once, and after annealing, finish rolling is carried out once to obtain an aluminum foil with a thickness of 13.8 μm, and then, second finish rolling is carried out to obtain an aluminum foil roll with a thickness of 8 μm;

[0093] In the rough rolling process, the rolling force of the first pass is 2200 KN, and the rolling force of the second pass is 2450 KN; the rolling speed of the first pass is 720 m / min, and the rolling speed of the second pass is 1100 m / min; the uncoiling tension of the first pass is 27 N / mm 2 , and the uncoiling tension of the second pass is 34 N / mm 2 ; the oil temperature of the first pass is 31℃, and the oil temperature of the second pass is 29℃, the rolling oil conditions of the first-pass and second-pass rough rolling are as follows: the rough rolling viscosity is 2.13 cst, the content of additive 1 is 7.1%, the content of additive 2 is 7.6%, and the content of additive 3 is 0.37%; the rough rolling roller Ra is 0.16, the crown is 30 μm, and the roller diameter is 279.989 mm / 279.989 mm;

[0094] In the annealing process, the annealing temperature is controlled to be 210℃, and the holding time is 16 hours;

[0095] The reduction of the two finish rolling is 30-13.8-8 μm; the rolling force of the first pass of finish rolling is 2850 KN, the rolling speed is 1120 m / min, and the unwinding tension is 58 N / mm 2 , the oil temperature is 32℃; the rolling force of the second pass of finish rolling is 3900 KN, the rolling speed is 705 m / min, and the unwinding tension is 65 N / mm 2 , the oil temperature is 45℃; the rolling oil conditions are: viscosity is 1.92 cst, additive 1 content is 6.6%, additive 2 content is 1.6%, and additive 3 content is 0.06%; the roughness Ra of the finish rolling roller is 0.065, the crown is 50 μm, and the roller diameter is 239.994 / 239.994 mm;

[0096] g, slitting: the 8 μm aluminum foil roll obtained after rolling is subjected to one-time slitting by using a Compton slitting machine, and the one-time slitting speed is controlled to be 500 m / min;

[0097] h, corona: the roll obtained after one-time slitting is subjected to one-time corona treatment by using a 1700 mm wide corona machine (its model is Baolusi), the corona speed is controlled to be 150 m / min, the corona power is 115 KW, and the corona frequency is 1 time;

[0098] I, fine cutting: fine cutting is carried out by using a Wanying aluminum foil slitting machine according to requirements, the fine cutting speed is 180 m / min, and the finished product obtained after fine cutting is packaged.

[0099] After detection, the unit area mass of the battery aluminum foil obtained in the embodiment is 22.19 g / m 2 , the tensile strength is 289 MPa, the elongation is 3.86%, and the surface dyne value is 42 dyn / cm.

Claims

1. An ultra-thin, high-performance 8μm double-sided photovoltaic cell aluminum foil, characterized by: The ultra-thin high-performance 8μm double-sided photovoltaic cell aluminum foil has a thickness of 8μm, a strength of ≥280MPa, an elongation of ≥3.5%, and a mass per unit area of ​​21.02 to 22.33g / m 2 , dyne value ≥35Dyne / cm.

2. The ultra-thin, high-performance 8μm double-sided photovoltaic cell aluminum foil according to claim 1, characterized in that: The chemical composition and mass percentage of each alloy in the ultra-thin, high-performance 8μm double-sided photovoltaic cell aluminum foil are as follows: Si 0.110-0.145%, Fe 0.400-0.445%, Cu 0.150-0.180%, Mn 0.020-0.040%, Mg≤0.01%, Zn≤0.1%, Ti≤0.03%, and the balance is Al and unavoidable impurity elements; the Al content is ≥99.2%.

3. A method for preparing an ultra-thin, high-performance 8μm double-sided photovoltaic cell aluminum foil, characterized in that: The preparation method comprises the following steps: a. Melting: adding a pure aluminum ingot into a melting furnace for melting, and adjusting the composition of the alloy according to the content requirements of the chemical components of each alloy in the ultra-thin high-performance 8μm double-sided photovoltaic cell aluminum foil after melting, so that the alloy liquid obtained by melting meets the content requirements of the chemical components of each alloy in the battery aluminum foil according to claim 2; b. Refining: Refining the alloy liquid obtained in step a, performing three slag removals during the refining process, and the hydrogen content is ≤0.08ml / 100gAl; c. Filtration: The alloy liquid obtained after slagging is double filtered using a plate filter box and a tube filter box; d. Casting and rolling: The filtered aluminum liquid flows into the front box and casting nozzle, and is cast and rolled into cold-rolled billets by casting rollers; e. Cold rolling: The cold rolled billet obtained by casting and rolling is cold rolled in six passes to form an aluminum foil billet with a finished thickness of 0.20 mm; f. Rolling: The obtained aluminum foil blank is subjected to two rough rolling passes, the first pass and the second pass, to obtain an aluminum foil with a thickness of 30 μm; then, an annealing is performed, and after the annealing, a finish rolling is performed to obtain an aluminum foil with a thickness of 13.8 μm, and then a second finish rolling is performed to obtain an aluminum foil coil with a thickness of 8 μm; g. Slitting: Slitting the 8 μm aluminum foil coil obtained after rolling; h. Corona treatment: subject the material roll obtained after the first slitting to a corona treatment; I. Precision cutting: Precision cutting is carried out according to the requirements, and the finished products are packaged after precision cutting.

4. The method for preparing the ultra-thin, high-performance 8 μm double-sided photovoltaic cell aluminum foil according to claim 1, characterized in that: During the smelting in step a, the temperature is controlled at 720-760° C.; During the refining in step b, the refining temperature is controlled to be 750-780°C; pure argon is used for refining, and the argon flow rate is 8-12m 2 / h, the bubble height during refining is ≤250mm, the refining frequency is 3 times, and the refining time each time is 20-30min; the bubble height during refining in the holding furnace is ≤180mm, and the refining frequency is 2-3 times.

5. The method for preparing the ultra-thin, high-performance 8μm double-sided photovoltaic cell aluminum foil according to claim 1, characterized in that: During the casting and rolling process in step d, the casting and rolling speed is 750-850 mm / min, the casting and rolling zone length is 58-64 mm, the rolling force is 3500-4000 kN, and the holding furnace outlet temperature is 730±5°C; the thickness of the obtained cold-rolled billet is 6.5-7 mm.

6. The method for preparing the ultra-thin, high-performance 8 μm double-sided photovoltaic cell aluminum foil according to claim 1, characterized in that: The reduction of the six cold rolling passes in step e is 6.5-3.8-2.0-1.2-0.65-0.34-0.20 mm; after rolling 3.8 mm, an O-state annealing is performed, the annealing temperature is 550±30° C., and the annealing time is 6+15 h.

7. The method for preparing the ultra-thin, high-performance 8 μm double-sided photovoltaic cell aluminum foil according to claim 1, characterized in that: The reduction of the two rough rollings in step f is 200-80-30 μm; the rolling force of the first rough rolling is 2000-2500 KN, the rolling speed is 650-850 m / min, and the unwinding tension is 25-55 N / mm 2 , oil temperature is 28~35℃; the rolling force of the second rough rolling is 2100~2600KN, the rolling speed is 900~1200m / min, and the uncoiling tension is 25~60N / mm 2 The oil temperature is 25-35°C; the rolling oil conditions are: viscosity 2.0-2.3Cst, additive 1 content 5.5-8.5%, additive 2 content 6.0-8.0%, additive 3 content 0.30-0.40%; the roughness Ra of the roughing roll is 0.15-0.18, the crown is 30μm, and the roll diameter is 270-280mm; During the annealing in step f, the annealing temperature is 210±10° C. and the holding time is 12 to 16 hours.

8. The method for preparing the ultra-thin, high-performance 8 μm double-sided photovoltaic cell aluminum foil according to claim 1, characterized in that: The reduction of the two finishing rolling in step f is 30-13.8-8 μm; the rolling force of the first finishing rolling is 2300-3500 KN, the rolling speed is 850-1150 m / min, and the unwinding tension is 30-85 N / mm 2 , oil temperature is 30~35℃; the second pass finishing rolling force is 3000~4500KN, the rolling speed is 600~850m / min, and the uncoiling tension is 45~85N / mm 2 , oil temperature is 40-48℃; rolling oil conditions are: viscosity is 1.90-2.0cst, additive 1 content is 5.0-7.0%, additive 2 content is 1.0-3.5%, additive 3 content is 0-0.1%; the roughness Ra of the finishing roll is 0.06-0.08, the convexity is 50μm, and the roll diameter is 240±0.5mm.

9. The method for preparing the ultra-thin, high-performance 8 μm double-sided photovoltaic cell aluminum foil according to claim 7 or 8, characterized in that: The additive 1 is a mixture of C10-16 mixed primary alcohols and methyl dodecanoate, and the mixing mass ratio between the C10-16 mixed primary alcohols and methyl dodecanoate is 1:6-8; the additive 2 is a C10-16 mixed primary alcohol; and the additive 3 is lauric acid, and the acid value of the lauric acid is 280 mg KOH / g.

10. The method for preparing the ultra-thin, high-performance 8 μm double-sided photovoltaic cell aluminum foil according to claim 1, characterized in that: The primary slitting in step g is performed using a Comp slitting machine, and the primary slitting speed is controlled to be 350-550 m / min; in the corona process in step h, a 1700 mm wide corona machine is used, the corona speed is controlled to be 100-150 m / min, the corona power is 80-120 kW, and the number of corona times is 1; during the fine cutting in step I, a Wanying aluminum foil slitting machine is used, and the slitting speed is 180-220 m / min.