CN114122304A - Rare earth new power supply pole piece, preparation method thereof and battery prepared from same - Google Patents

Abstract

The invention belongs to the technical field of secondary battery manufacturing, and particularly relates to a novel rare earth power pole piece, a preparation method thereof and a battery prepared from the same. Pre-pressing and rolling current collector foamed nickel, reserving a white edge on one edge, and drawing the blank into a welding platform; cutting the nickel-plated steel strip into a plurality of sections, respectively welding the sections on the current collector foamed nickel white edge by adopting laser, sticking adhesive tapes on two sides after prepressing, wherein the length of each section of the nickel-plated steel strip is integral multiple of the width of the polar plate; the slurry enters a slurry spraying station to be sprayed with slurry through traction; the mixture is drawn into a drying chamber for drying and rolling; and transversely cutting, and obtaining the pole piece after the pole lugs are formed and cut. According to the invention, the nickel-plated steel strip is welded with the current collector foamed nickel in a segmented and pre-welded manner, the pollution of slurry to the adhesive tape is reduced by adopting a spraying and feeding manner, the pole lug is formed by subsequent laser cutting, the pole plate and the pole lug are directly formed on line to prepare the pole piece, the pole piece is continuously produced on line and integrally prepared, the advantages of high production efficiency and intelligence are achieved, and the utilization rate of the adhesive tape is high.

Description

Rare earth new power supply pole piece, preparation method thereof and battery prepared from same

Technical Field

The invention belongs to the technical field of secondary battery manufacturing, and particularly relates to a novel rare earth power pole piece, a preparation method thereof and a battery prepared from the same.

Background

The high-capacity water system secondary battery has the advantages of high safety, long service life, wide environmental temperature range (-55-60 ℃) and the like, and is applied in a large amount all the time, but the high-capacity water system secondary battery has the advantages that the battery cell is formed by alternately combining the positive electrode plate and the negative electrode plate, and the efficient production of the high-quality electrode plates is always a key process of the production flow.

In the prior art, after a pole plate is produced, a conductive tab is specially welded to form the pole plate, an adhesive tape is required to be used in the production process of the pole plate to ensure that a reserved white edge is not polluted, the adhesive tape is required to be removed before the pole plate is produced, the risk of tearing the white edge exists in the process of removing the adhesive tape and an operator is required to watch, and a new adhesive tape is required to be pasted after the tab is welded, so that the problems of multiple turnover processes, low labor efficiency, lower adhesive tape utilization rate lower than 50% and the like exist in the welding process. If a pole piece preparation method for directly forming a pole plate and a pole lug on line can be developed, the positive pole and the negative pole can be applied, and the pole piece can also adapt to different thicknesses, so that the method has industrial and commercial values.

Disclosure of Invention

The invention aims to provide a preparation method of a rare earth new power pole piece, which can realize the on-line direct forming preparation of the pole piece by the pole plate and the pole lug, realize the on-line continuous production and integrated preparation of the pole piece, has the advantages of high production efficiency and more intelligent production, high utilization rate of adhesive tapes, can be applied to both the positive pole and the negative pole and can also adapt to different thicknesses; the invention also provides a novel rare earth power pole piece prepared by the preparation method; the invention also provides a battery prepared from the pole piece.

The invention provides a preparation method of a rare earth new power supply pole piece, which comprises the following steps:

(1) pre-pressing and rolling current collector foamed nickel, reserving a white edge on one edge of the current collector foamed nickel, and drawing the current collector foamed nickel into a welding platform;

(2) cutting the nickel-plated steel strip into a plurality of sections, respectively welding the sections on the white edges of the current collector foamed nickel obtained in the step (1) by adopting laser, prepressing, and then pasting adhesive tapes on the two sides; wherein the length of each section of nickel-plated steel strip is integral multiple of the width of the polar plate;

(3) the slurry enters a slurry spraying station to be sprayed with slurry through traction;

(4) the mixture is drawn into a drying chamber for drying and then is rolled after being discharged;

(5) and transversely cutting, and then forming and cutting a lug to obtain the pole piece.

The foamed nickel as a current collector has the advantage of strong adhesion of a battery active material, but has the disadvantage of extension after rolling, which is a technical bottleneck that the prior art always wants to realize the molding of an integrated pole piece but cannot realize the molding all the time. The nickel-plated steel strip cannot be welded on the white edge of the current collector foamed nickel, because the foamed nickel extends after subsequent rolling, but the nickel-plated steel strip does not extend, and the whole base band (the base band refers to the foamed nickel welded with the nickel-plated steel strip) can deform and even curl, so that the polar plate is scrapped. According to the invention, the nickel-plated steel strip is cut into a plurality of sections and is respectively welded on the white edges of the current collector foamed nickel in a sectional welding manner, so that the problem of asynchronous extension of the nickel-plated steel strip and the foamed nickel is solved, the pollution of slurry to the adhesive tape is reduced by adopting a slurry spraying feeding manner, and the pole ear is formed by subsequent laser cutting, so that the pole piece is directly formed and prepared on line by the pole plate and the pole ear, the on-line continuous production of the pole piece is realized, and the integral pole piece forming is realized. The length of each section of nickel-plated steel strip is integral multiple of the width of the pole plate, namely, each cutting is not necessarily carried out along the joint of the two sections of nickel-plated steel strips, but the length of the nickel-plated steel strip can ensure that the last cut can be cut at the joint of the two sections of nickel-plated steel strips when the nickel-plated steel strips are cut. For example, if the width of the pole plate is 100mm, and the length of the nickel-plated steel strip is an integral multiple of 100mm, for example, 300mm, the base band is delivered, the cutting knife will cut three times rapidly during the subsequent cutting, and the last cut is cut at the joint of two sections of nickel-plated steel strips. In order to prevent the deviation rectification difficulty, a white edge is reserved on only one edge of the foamed nickel, the yield is high, and the foamed nickel cannot be arranged on both sides or in the middle. The problem that the slurry pollutes the surface of the adhesive tape can be effectively solved by adopting a slurry spraying mode.

If the number of the foam nickel holes is too many and the pore diameter is small, the battery slurry is not easy to spray, and the spraying pressure is increased, so that the base band is easy to break in the moving process; if the number of holes is too small, the hole diameter is too large, the battery slurry is filled too much, and the battery slurry is easy to crack after subsequent final rolling. The thickness selection factor of the foam nickel is directly related to the number of the holes, and if the thickness is too thick, the diameter of each roll of the foam nickel is too large, so that the operation is not good in production; if the thickness is too thin, the quality of the foam nickel is not good; the width of the foamed nickel is considered based on the size and the elongation of the polar plate, if the width is too small, the strength of the foamed nickel is greatly reduced, and the foamed nickel is difficult to adapt to continuous production; if the width is too large, the absolute value generated by the transverse elongation rate is increased, and the transverse deformation of the rolled polar plate exceeds the upper limit alarm value, so that the scrappage probability of the polar plate is increased. In consideration of factors such as welding and prepressing of a subsequent nickel-plated steel strip, the number of holes of the current collector foamed nickel in the step (1) is preferably 90-120 ppi, the thickness is 0.7-2.4 mm, and the width is 60-300 mm.

One side of the foam nickel is reserved with a width of 8-10 mm and is used as a laminating part welded with the nickel-plated steel strip, namely a white edge. In order to prevent the deviation rectification difficulty, a white edge is reserved on only one edge of the foamed nickel, the yield is high, and the foamed nickel cannot be arranged on both edges or in the middle; the place where the battery material is attached (i.e. the place where the slurry is sprayed in step (4)) is called a non-white edge. The white edge needs to be welded with a nickel-plated steel strip, and after the porous foamed nickel is pre-pressed and rolled, the density is increased, the contact surface with the nickel-plated steel strip is increased, and the subsequent laser welding is facilitated. However, the white edge cannot be pressed too thin, and if the white edge is too thin, the mechanical strength of the white edge is reduced, and the white edge is easy to tear; the non-white edge pre-pressing mainly controls the sizing amount in unit area, so that the final specific gravity in unit area is controlled, the pre-pressing thickness needs to be determined according to the requirements of subsequent polar plates, the pre-pressing thickness cannot be too thick, the pre-pressing thickness is too thick, the sizing amount is too much, subsequent rolling is easy to crack, the pre-pressing thickness cannot be too thin, the sizing amount is small due to too thin, and the battery capacity is too low. Preferably, the pre-pressing roll in the step (1) is as follows: and pre-pressing and rolling the current collector foamed nickel, wherein one edge of the current collector foamed nickel is pre-pressed to be 8-10 mm in width and serves as a white edge, the thickness of the white edge is pre-pressed to be 0.2-0.5 mm, and the thickness of the non-white edge is pre-pressed to be 0.5-0.9 mm.

If the nickel-plated steel strip is too thin, the nickel-plated steel strip is difficult to produce, the purchase cost is increased sharply, the rigidity of the steel strip is low, each section of the nickel-plated steel strip is grabbed in the production process, and the steel strip is easy to bend, so that the left deviation and the right deviation are large; if the thickness is too thick, on one hand, the laser welding power needs to be greatly improved to be melted through, so that the equipment investment is increased, and on the other hand, the weight is increased too much, so that the specific mass energy of the battery is reduced. The width of the nickel-plated steel strip is determined according to the requirements of the pole piece. As a preferable scheme, the nickel-plated steel strip cannot be too narrow, if the nickel-plated steel strip is too narrow, the protruding end of the formed tab is too small to meet the requirement of welding with the tab, and the tab cannot be too wide, so that the invalid space in the battery is increased, and the volumetric specific energy of the battery is indirectly reduced. Preferably, the thickness of the nickel-plated steel strip in the step (2) is 0.05-1.5 mm, and the width is 15-35 mm.

And (2) cutting the nickel-plated steel strip into a plurality of sections, wherein each section of nickel-plated steel strip cannot be too long, on one hand, the gripping of a robot has certain size upper limit limitation, on the other hand, the control is required to be within the elongation upper limit range, and on the third hand, the frequency and the plate width of the subsequent cutting also need to be considered, usually, 2 or 3 or more sections are continuously cut to pull the base strip to move forwards, namely, the intermittent continuous movement is carried out, so that the length of each section of nickel-plated steel strip is 2N or 3N times of the plate width. Preferably, the length of each section of nickel-plated steel strip in the step (2) is 300-1000 mm, and is 2N times or 3N times of the width of the polar plate, and N is an integer of 1-9 Arabic numerals.

Preferably, in the step (2), the laser welding adopts a mode of continuously spot-welding to form a welding seam, namely spot-shaped continuous welding, and the appearance is linear; in order to increase the conductivity, the welding seams are two; the welding lines are parallel to the long edges of the nickel-plated steel strip, and in order to avoid heat concentration, the distance between the two welding lines is a certain gap; the maximum width of the white edge is only 10mm, and the width of the welding seam is 2-3 mm, so that the distance between the two welding seams cannot be too far, and the optimal distance is 2-3 mm. Welding back, the surface has certain burr, carries out the pre-compaction and can eliminate the burr, then pastes the sticky tape, thoroughly eliminates burr hidden danger, stops the little short circuit of burr.

Preferably, the spraying slurry in the step (3) is double-sided spraying. The adhesive tape is adhered to the nickel-plated steel strip after welding, and the adhesive tape is continuously used in the follow-up process, so that the adhesion of slurry is reduced as much as possible, and the problem that the slurry pollutes the surface of the adhesive tape can be effectively solved by adopting double-sided spraying. At present, water-based slurry is usually sprayed on one side, and negative pressure material suction is carried out on the other side, so that the base band is easy to shift to one side in the forward moving process of the base band, and the risk of band breakage exists; and the double-sided spraying is adopted, so that the stress on two sides is uniform.

Preferably, the drying chamber in the step (4) is a bidirectional vertical drying chamber, the bidirectional vertical drying chamber is composed of an ascending section drying area and a descending section drying area, the ascending section drying area and the descending section drying area are parallel to each other and are vertical to the ground, the ascending section drying area and the descending section drying area are divided into 4-6 sections of temperature drying areas, the ascending section has 2-3 sections of drying areas, and the descending section has 2-3 sections of drying areas. The thick liquids after the spraying need quick drying, and the baseband surface that leads to for avoiding appearing thick liquids sagging phenomenon is inhomogeneous, and the stoving region falls into the multistage, is favorable to temperature control even, adopts and conveniently dries from top to bottom perpendicularly, reduces the whole length of equipment on the one hand, and on the other hand also because river system thick liquids characteristic, the vertical mode is dried evenly fast, still is favorable to the vapor quick discharge of dry production, improves drying efficiency and thick liquids drying quality.

If the drying temperature of the water-based slurry is too high, the drying speed is easy to be too high, the surface of the slurry is hard and easy to crack; if the drying temperature is too low, moisture in the slurry is not easy to volatilize, the drying temperature of all drying zones is preferably within 90-145 ℃, the temperature of the starting drying zone is high, the temperature of the starting drying zone is preferably 120-145 ℃, the temperature of the middle drying zone is alternated, the temperature difference between the front drying zone and the rear drying zone is 5-15 ℃, temperature atmosphere fluctuation can be formed, the discharge of water vapor is facilitated, the temperature of the tail drying zone is low, the temperature of the tail drying zone is preferably 90-110 ℃, and cracking caused by high cooling speed after the slurry is dried is avoided.

Preferably, the rolling pressure in the step (4) is 80-400 t. After correcting offset, the dried base band is fed into a roller press at the temperature of 40-50 ℃, and is rolled into a base band with a certain thickness under a certain pressure, different pressures are set according to requirements of active materials of battery materials, the thickness of pole pieces and the compaction density, the pressure of a positive pole piece is usually lower and can be 80t at the lowest, and if the pressure is too low, the binding degree between the active materials of the pole pieces is not enough, so that the service life of the pole piece is influenced; the pressure of the negative electrode is high, the maximum pressure reaches 400t, if the pressure is too high, the equipment investment is too high, and the negative electrode active material particles are easy to crush too much, so that the rate performance of the battery is influenced.

Preferably, step (5) is: and transversely cutting according to set parameters, scanning the cut pole plates by a vision device, enabling the qualified pole plates to enter a laser cutting station by a robot, and then preparing pole pieces after forming and cutting pole lugs. The transversely cut polar plates are rectangular or square, for example, the first starting polar plate is generally used as a waste plate in the cutting process, some polar plates are cut into oblique plates in the subsequent intermittent continuous cutting, the on-line monitoring is carried out through a visual device, and grabbing which does not meet the requirement is placed on one side and is manually processed; and cutting qualified pole plates, directly grabbing and placing the pole plates at a laser cutting station by a robot, carrying out tab forming cutting by a laser cutting machine, and preparing the pole plates after cutting. Preferably, the pole plate cut in the step (5): the width is 50-120 mm, the length is 65-330 mm, the thickness is 0.16-0.4 mm, the length of the polar plate is equal to the width of the foam nickel and the width of the nickel-plated steel strip, namely the overlapping part, namely the width of the white edge; the pole piece correspondingly prepared is as follows: the width is 50-120 mm, the length is 65-330 mm, and the thickness is 0.16-0.4 mm.

The invention also provides a novel rare earth power pole piece prepared by any one of the preparation methods.

The method is suitable for preparing the anode and the cathode, is also suitable for preparing different thicknesses, and has higher yield.

The invention also provides a battery prepared by the novel rare earth power supply pole piece, and the preparation process adopts the existing process, the novel rare earth power supply pole piece is subjected to the subsequent powder cleaning process, positive and negative pole pieces and a diaphragm are alternately laminated to form a battery core, and the battery core is subjected to shell filling, liquid injection, sealing and formation to prepare the finished battery.

In summary, the invention has the following advantages:

(1) the foamed nickel as a current collector has the advantage of strong adhesion of a battery active material, but has the disadvantage of extension after rolling, which is a technical bottleneck that the prior art always wants to realize the molding of an integrated pole piece but cannot realize the molding all the time. The nickel-plated steel strip cannot be welded on the white edge of the current collector foamed nickel, because the foamed nickel extends after subsequent rolling, but the nickel-plated steel strip does not extend, the whole base strip can deform and even curl, and the polar plate is scrapped. According to the invention, the nickel-plated steel strip is cut into a plurality of sections and is respectively welded on the white edges of the current collector foamed nickel in a sectional welding mode, namely, the nickel-plated steel strip is welded with the current collector foamed nickel in advance in sections, so that the problem of asynchronous extension of the nickel-plated steel strip and the foamed nickel is solved, the pollution of slurry to the adhesive tape is reduced by adopting a feeding mode of spraying slurry, the pole lug is cut and formed by subsequent laser, the pole piece is directly formed and prepared on line by the pole plate and the pole lug, the on-line continuous production of the pole piece is realized, and the integral pole piece forming is realized.

(2) Compared with the prior art, the invention prepares the pole piece by firstly producing the pole plate and then specially and independently welding the pole lugs, and also has the advantages of high production efficiency and more intelligent production.

(3) In order to prevent the deviation rectification difficulty, a white edge is reserved on only one edge of the foamed nickel, so that the yield is high.

(4) The problem that the slurry pollutes the surface of the adhesive tape can be effectively solved by adopting a slurry spraying mode.

(5) The anode and the cathode can be applied, and can be suitable for different thicknesses, and the application range is wide.

(6) The invention has the advantages of almost 100 percent of utilization rate of the adhesive tape, economy and environmental protection.

Drawings

FIG. 1 is a process flow chart of the preparation method of the novel rare earth power pole piece of the invention.

Detailed Description

The present invention will be further described with reference to the following examples.

Example 1

A preparation method of a rare earth new power pole piece comprises the following steps:

(1) selecting foamed nickel with the hole number of 100ppi, the thickness of 2.0mm and the width of 200mm as a current collector, pre-pressing and rolling the foamed nickel of the current collector, pre-pressing one edge of the foamed nickel of the current collector to the width of 9mm as a white edge, pre-pressing the white edge to the thickness of 0.4mm, pre-pressing the non-white edge to the thickness of 0.7mm, and dragging the pre-pressed nickel to enter a welding platform;

(2) selecting a nickel-plated steel strip with the thickness of 1.0mm and the width of 22mm, cutting the nickel-plated steel strip into a plurality of sections, wherein the length of each section of the nickel-plated steel strip is 300mm and is 3 times of the width of a polar plate, respectively performing laser welding on the white edge of the current collector foamed nickel obtained in the step (1) in a spot welding manner to form a welding line, welding two welding lines, the welding line is parallel to the long edge of the nickel-plated steel strip, the distance between the two welding lines is 3mm, and performing double-sided tape pasting after prepressing;

(3) the slurry is sprayed on the two sides of the slurry spraying station by traction;

(4) the drying chamber is drawn to enter the drying chamber for drying, the drying chamber is a two-way vertical drying chamber, the two-way vertical drying chamber consists of an ascending section drying area and a descending section drying area, the ascending section drying area and the descending section drying area are parallel to each other and are vertical to the ground, the ascending section drying area and the descending section drying area are divided into 6 sections of temperature drying areas, the ascending section drying area has 3 sections of drying areas, the descending section drying area has 3 sections of drying areas, the temperature of the starting point drying area is high, the temperature of the middle drying area is alternated, and the temperature of each temperature area from ascending to descending is as follows: rolling at 140 + -2 deg.C, 125 + -2 deg.C, 130 + -2 deg.C, 115 + -2 deg.C, 120 + -2 deg.C, and 105 + -2 deg.C, with rolling pressure of 200 t;

(5) transversely cutting according to the set parameters, and cutting out the polar plate: the width is 100mm, the length is 213mm, and the thickness is 0.3 mm; the pole piece correspondingly prepared is as follows: the width is 100mm, the length is 213mm, and the thickness is 0.3 mm; and scanning the cut pole plate by a vision device, enabling the qualified pole plate to enter a laser cutting station by a robot, and then preparing the pole piece after the pole lug is formed and cut.

The pole piece manufactured by the embodiment has the adhesive tape utilization rate improved to 98.5% from 46% in the prior art, and directly cancels a pole lug independent welding process in the prior art, namely an original pole piece production line containing a pole lug independent welding process needs 16 welding devices corresponding to two substrate coating production lines, each welding device needs two workers, 1 worker is responsible for operating the welding device and turning around, 1 worker is responsible for pole lug arrangement, substrate powder removal and pole piece counterweight, and the substrate coating production line is 6 persons (two adhesive tape tearing persons containing two substrate coating production lines) and totally 38 persons.

The adhesive tape tearing station is omitted in the embodiment, the corresponding labor number is 0, an independent tab welding machine is not needed, the substrate is produced and directly enters the laser cutting tab forming pole piece station through a robot arm after being detected to be qualified, the whole automatic communication is realized, 1 person is added to an automatic monitoring person, the manual turnover from the substrate to tab welding is also omitted, the number of workers on a pole piece production line is reduced to 6 persons, the manual turnover frequency of the pole piece is reduced by 50%, and the yield of the embodiment reaches 98.5%.

And (3) performing a subsequent powder cleaning process on the prepared pole piece, alternately laminating a positive pole piece, a negative pole piece and a diaphragm to form a battery core, and performing shell filling, liquid injection, sealing and formation to manufacture a finished battery.

Example 2

A preparation method of a rare earth new power pole piece comprises the following steps:

(1) selecting foamed nickel with the hole number of 90ppi, the thickness of 1.0mm and the width of 100mm as a current collector, pre-pressing and rolling the foamed nickel of the current collector, pre-pressing one of the foamed nickel of the current collector to the width of 8mm as a white edge, pre-pressing the white edge to the thickness of 0.2mm, pre-pressing the non-white edge to the thickness of 0.5mm, and dragging the current collector to a welding platform;

(2) selecting a nickel-plated steel strip with the thickness of 0.1mm and the width of 15mm, cutting the nickel-plated steel strip into a plurality of sections, wherein the length of each section of the nickel-plated steel strip is 500mm, the length of each section of the nickel-plated steel strip is 10 times of the width of a polar plate, respectively welding the nickel-plated steel strip on the white edge of the current collector foamed nickel obtained in the step (1) by adopting a spot welding mode to form a welding line, welding two welding lines, the welding line is parallel to the long edge of the nickel-plated steel strip, the distance between the two welding lines is 2mm, and pre-pressing and then carrying out double-sided tape pasting;

(3) the slurry is sprayed on the two sides of the slurry spraying station by traction;

(4) the drying chamber is drawn to enter the drying chamber for drying, the drying chamber is a two-way vertical drying chamber, the two-way vertical drying chamber consists of an ascending section drying area and a descending section drying area, the ascending section drying area and the descending section drying area are parallel to each other and are vertical to the ground, the ascending section drying area and the descending section drying area are divided into 6 sections of temperature drying areas, the ascending section drying area has 3 sections of drying areas, the descending section drying area has 3 sections of drying areas, the temperature of the starting point drying area is high, the temperature of the middle drying area is alternated, and the temperature of each temperature area from ascending to descending is as follows: rolling at 130 + -2 deg.C, 120 + -2 deg.C, 125 + -2 deg.C, 110 + -2 deg.C, 115 + -2 deg.C, and 100 + -2 deg.C under 80 t;

(5) transversely cutting according to the set parameters, and cutting out the polar plate: the width is 50mm, the length is 107mm, and the thickness is 0.2 mm; the pole piece correspondingly prepared is as follows: the width is 50mm, the length is 107mm, and the thickness is 0.2 mm; and scanning the cut pole plate by a vision device, enabling the qualified pole plate to enter a laser cutting station by a robot, and then preparing the pole piece after the pole lug is formed and cut.

The utilization rate of the adhesive tape of the pole piece manufactured by the embodiment is improved to 98% from 48% in the prior art, and the independent pole lug welding process in the prior art is directly cancelled, namely the original independent pole piece production line containing the pole lug welding process needs 24 welding devices corresponding to two substrate coating production lines, each welding device needs two workers, 1 worker is responsible for operating the welding device and turning around, 1 worker is responsible for arranging the pole lug, cleaning powder of the substrate and balancing the pole piece, and the substrate coating production line is 6 individuals (two adhesive tape tearing personnel containing the two substrate coating production lines), and the total number of the welding devices is 54 individuals. The adhesive tape tearing station is omitted in the embodiment, the corresponding labor number is 0, an independent tab welding machine is not needed, the substrate is produced and directly enters the laser cutting tab forming pole piece station through a robot arm after being detected to be qualified, the whole automatic communication is realized, 1 person is added to an automatic monitoring person, the manual turnover from the substrate to tab welding is also omitted, the number of workers on a pole piece production line is reduced to 6 persons, the manual turnover frequency of the pole piece is reduced by 50%, and the yield of the embodiment reaches 98%.

And (3) performing a subsequent powder cleaning process on the prepared pole piece, alternately laminating a positive pole piece, a negative pole piece and a diaphragm to form a battery core, and performing shell filling, liquid injection, sealing and formation to manufacture a finished battery.

Example 3

A preparation method of a rare earth new power pole piece comprises the following steps:

(1) selecting foamed nickel with the hole number of 120ppi, the thickness of 2.4mm and the width of 300mm as a current collector, pre-pressing and rolling the foamed nickel of the current collector, pre-pressing one of the foamed nickel of the current collector to the width of 10mm as a white edge, pre-pressing the white edge to the thickness of 0.5mm, pre-pressing the non-white edge to the thickness of 0.9mm, and dragging the current collector to a welding platform;

(2) selecting a nickel-plated steel strip with the thickness of 1.5mm and the width of 35mm, cutting the nickel-plated steel strip into a plurality of sections, wherein the length of each section of the nickel-plated steel strip is 720mm, the length of each section of the nickel-plated steel strip is 6 times of the width of a polar plate, laser welding the nickel-plated steel strip on the white edge of the current collector foamed nickel obtained in the step (1) respectively in a spot welding mode to form a welding line, welding two welding lines, and pre-pressing to carry out double-sided tape pasting, wherein the distance between the two welding lines is 3 mm;

(3) the slurry is sprayed on the two sides of the slurry spraying station by traction;

(4) the drying chamber is a bidirectional vertical drying chamber, the bidirectional vertical drying chamber consists of an ascending section drying area and a descending section drying area, the ascending section is divided into 6 sections of temperature drying areas, the ascending section is provided with 3 sections of drying areas, the descending section is provided with 3 sections of drying areas, the temperature of the starting point drying area is high, the temperature of the middle drying area is alternated, and the temperature of each temperature area from ascending to descending is as follows: rolling at 140 + -2 deg.C, 125 + -2 deg.C, 130 + -2 deg.C, 115 + -2 deg.C, 120 + -2 deg.C, and 105 + -2 deg.C under 100 t;

(5) transversely cutting according to the set parameters, and cutting out the polar plate: the width is 120mm, the length is 325mm, and the thickness is 0.4 mm; the pole piece correspondingly prepared is as follows: the width is 120mm, the length is 325mm, and the thickness is 0.4 mm; and scanning the cut pole plate by a vision device, enabling the qualified pole plate to enter a laser cutting station by a robot, and then preparing the pole piece after the pole lug is formed and cut.

The pole piece manufactured by the embodiment has the adhesive tape utilization rate improved to 99% from 47% in the prior art, and directly cancels a pole lug independent welding process in the prior art, namely an original pole piece production line containing a pole lug independent welding process needs 12 welding devices corresponding to two substrate coating production lines, each welding device needs two workers, 1 worker is responsible for operating the welding device and transferring, 1 worker is responsible for arranging the pole lug, cleaning powder of the substrate and balancing weight of the pole piece, and in addition, 6 persons (two adhesive tape tearing persons containing two substrate coating production lines) of the substrate coating production line need 30 persons in total. The adhesive tape tearing station is omitted in the embodiment, the corresponding labor number is 0, an independent tab welding machine is not needed, the substrate is produced and directly enters the laser cutting tab forming pole piece station through a robot arm after being detected to be qualified, the whole automatic communication is realized, 1 person is added to an automatic monitoring person, the manual turnover from the substrate to tab welding is also omitted, the number of workers on a pole piece production line is reduced to 6 persons, the manual turnover frequency of the pole piece is reduced by 50%, and the yield reaches 99%.

And (3) performing a subsequent powder cleaning process on the prepared pole piece, alternately laminating a positive pole piece, a negative pole piece and a diaphragm to form a battery core, and performing shell filling, liquid injection, sealing and formation to manufacture a finished battery.

Example 4

The preparation method of the rare earth new power pole piece is basically consistent with that of the embodiment 1, and the only difference is that: the step (4) is as follows: the drying agent is drawn into a drying chamber for drying, the drying chamber is a common drying device, and the drying temperature is as follows: rolling after the temperature is 100 ℃, wherein the rolling pressure is 200 t.

The pole piece manufactured by the embodiment has the advantages that the utilization rate of the adhesive tape is improved to 91.2% from 46% in the prior art, the labor number is reduced to 7, the turnover frequency of the pole piece is reduced by 50%, and the yield reaches 91.2%.

As can be seen from the examples 1-4, the drying chamber in the step (4) adopts a bidirectional vertical drying chamber, and the yield is higher compared with that of the drying chamber adopting common drying equipment.

Comparative example 1

The preparation method of the rare earth new power pole piece is basically consistent with that of the embodiment 1, and the only difference is that: the length of each nickel-plated steel strip is 320mm, and the length of each nickel-plated steel strip is 3.2 times of the width of the plate.

The yield of the pole piece manufactured by comparative example 1 was 72.1%.

Since the length of each section of nickel-plated steel strip in the comparative example 1 is 3.2 times of the width of the pole plate and is not integral multiple, the joint of two sections of nickel-plated steel strips on some pole plates after cutting in the step (5) is not good.

As can be seen from example 1 and comparative example 1, the nickel-plated steel strip is cut into several sections in step (2), the length of each section of nickel-plated steel strip is integral multiple of the width of the electrode plate, and the yield is higher compared with non-integral multiple.

Comparative example 2

The preparation method of the rare earth new power pole piece is basically consistent with that of the embodiment 1, and the only difference is that: and (2) in the step (1), pre-pressing the two edges of the current collector foam nickel to the width of 9mm to be used as white edges, respectively welding the current collector foam nickel on each white edge obtained in the step (1) by adopting a spot welding mode, and welding two welding lines on each white edge.

The pole piece manufactured by the embodiment has the advantages that the utilization rate of the adhesive tape is improved to 75% from 46% in the prior art, 4 persons need to be added for automatic monitoring personnel, the number of manual workers is reduced to 9 persons, the turnover frequency of the pole piece is reduced by 50%, and the yield is only 75%.

It can be seen from example 1 and comparative example 2 that only one side of the current collector nickel foam has a white edge, and the current collector nickel foam is welded on the white edge of the current collector nickel foam in a spot welding mode, so that the yield is higher compared with the case that both sides of the current collector nickel foam are welded with the white edges.

It should be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention in any way, and that various changes and modifications may be made by those skilled in the art using the above teachings, such as by winding the positive and negative electrodes and the gel separator into equivalent embodiments. However, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention are within the protection scope of the technical solution of the present invention.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single technical solution, and such description of the embodiments is only for the sake of clarity, and those skilled in the art should take the description as a whole, and the technical solutions in the embodiments may be combined appropriately to form other embodiments understood by those skilled in the art.

Claims (10)

1. A preparation method of a rare earth new power pole piece is characterized by comprising the following steps:

(1) pre-pressing and rolling current collector foamed nickel, reserving a white edge on one edge of the current collector foamed nickel, and drawing the current collector foamed nickel into a welding platform;

(2) cutting the nickel-plated steel strip into a plurality of sections, respectively welding the sections on the white edges of the current collector foamed nickel obtained in the step (1) by adopting laser, prepressing, and then pasting adhesive tapes on the two sides; wherein the length of each section of nickel-plated steel strip is integral multiple of the width of the polar plate;

(3) the slurry enters a slurry spraying station to be sprayed with slurry through traction;

(4) the mixture is drawn into a drying chamber for drying and then is rolled after being discharged;

(5) and transversely cutting, and then forming and cutting a lug to obtain the pole piece.

2. The preparation method of the rare earth new power pole piece according to claim 1, characterized in that: in the step (1), the number of pores of the current collector foamed nickel is 90-120 ppi, the thickness is 0.7-2.4 mm, and the width is 60-300 mm.

3. The preparation method of the rare earth new power pole piece according to claim 1, characterized in that: the pre-pressing roll in the step (1) is as follows: and pre-pressing and rolling the current collector foamed nickel, wherein one edge of the current collector foamed nickel is pre-pressed to be 8-10 mm in width and serves as a white edge, the thickness of the white edge is pre-pressed to be 0.2-0.5 mm, and the thickness of the non-white edge is pre-pressed to be 0.5-0.9 mm.

4. The preparation method of the rare earth new power pole piece according to claim 1, characterized in that: the thickness of the nickel-plated steel strip in the step (2) is 0.05-1.5 mm, and the width of the nickel-plated steel strip is 15-35 mm; the length of each section of nickel-plated steel strip is 300-1000 mm, the length of each section of nickel-plated steel strip is 2N times or 3N times of the width of the polar plate, and N is an integer of Arabic numerals 1-9.

5. The preparation method of the rare earth new power pole piece according to claim 2, characterized in that: in the step (2), the laser welding adopts a mode of forming welding seams by continuous spot welding, the number of the welding seams is two, and the distance between the two welding seams is 2-3 mm.

6. The preparation method of the rare earth new power pole piece according to claim 1, characterized in that: and (4) spraying the slurry in the step (3) by double-sided spraying.

7. The preparation method of the rare earth new power pole piece according to claim 1, characterized in that: the drying chamber in the step (4) is a bidirectional vertical drying chamber, the bidirectional vertical drying chamber consists of an ascending section drying area and a descending section drying area, the bidirectional vertical drying chamber is divided into 4-6 sections of temperature drying areas, the temperature of the starting drying area is 120-145 ℃, the temperature of the middle drying area is alternated, the temperature difference between the front drying area and the rear drying area is 5-15 ℃, the temperature of the tail drying area is 90-110 ℃, and the drying temperature of all the drying areas is within 90-145 ℃; and (4) rolling at the rolling pressure of 80-400 t.

8. The preparation method of the rare earth new power pole piece according to claim 1, characterized in that: the step (5) is as follows: transversely cutting according to set parameters, scanning the cut pole plates by a vision device, enabling the qualified pole plates to enter a laser cutting station by a robot, and preparing pole pieces after forming and cutting pole lugs; the pole plates cut in the step (5): the width is 50-120 mm, the length is 65-330 mm, and the thickness is 0.16-0.4 mm; the pole piece correspondingly prepared is as follows: the width is 50-120 mm, the length is 65-330 mm, and the thickness is 0.16-0.4 mm.

9. A new rare earth power pole piece prepared by the preparation method of any one of claims 1 to 8.

10. The battery prepared from the rare earth new power pole piece of claim 9 is characterized in that: the rare earth new power supply pole piece of claim 9 is subjected to a subsequent powder cleaning process, positive and negative pole pieces and a diaphragm are alternately laminated to form a battery cell, and the battery cell is manufactured through the steps of casing, liquid injection, sealing and formation.

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