Large cylindrical lithium battery adopting laser scribing technology

Abstract

The utility model belongs to the technical field of large cylindrical lithium batteries, and particularly relates to a large cylindrical lithium battery adopting a laser scribing technology, which adopts the following scheme that the large cylindrical lithium battery comprises a diaphragm, a positive plate, a negative plate, a laser scribing line and a roll core, the laser scribing line can be applied to the positive plate and the negative plate, and can be carved on a single-side plate; the lines can be scribed on both sides; the scribing angle E ranges from 0 degree to 90 degrees, the selection range of the scribing angle E is directly related to the width D of a material area of the pole piece, the wider the width D of the material area is, the larger the scribing angle E is in order to pursue the liquid injection speed, the narrower the width D of the material area is, and the smaller the scribing angle E is in order to pursue the infiltration effect. And the electrolyte injection time can be greatly shortened, meanwhile, the investment of electrolyte injection equipment is reduced, and the electrolyte infiltrates the battery well and has excellent cycle and rate charge-discharge performance.

Description

TECHNICAL FIELD

[0001] The utility model relates to big cylindrical lithium cell technical field especially relates to a big cylindrical lithium cell of adopting laser line technology. BACKGROUND

[0002] With the tesla 4680 model big cylindrical battery, the big cylindrical battery is popular in the market at present.

[0003] With the battery diameter gradually increases, the infiltration effect of electrolyte gradually drops, leading to battery injection time is too long, equipment cost increases, at the same time, electrolyte infiltration effect is not good, can obviously influence the cycle of battery and so on Performance, therefore, the utility model provides a big cylindrical lithium cell of adopting laser line technology, for solving the above -mentioned problem. UTILITY MODEL CONTENTS

[0004] Based on the background technology, with the battery diameter gradually increases, the infiltration effect of electrolyte gradually drops, leading to battery injection time is too long, equipment cost increases, at the same time, electrolyte infiltration effect is not good, can obviously influence the cycle of battery and so on Performance, technical problem, the utility model provides a big cylindrical lithium cell of adopting laser line technology.

[0005] The utility model provides a big cylindrical lithium cell of adopting laser line technology, including diaphragm, positive sheet, negative sheet, laser line and roll core, the laser line can be applied to the positive sheet, also can be applied to the negative sheet, can be engraved in single side sheet, also can both sides line is engraved;

[0006] Line angle E is between 0 and 90, its selection range has direct relation with the width D of material area of sheet, the wider width D of material area is, for pursuing injection speed, line angle E is greater, the narrower width D of material area is, for pursuing infiltration effect, line angle E is smaller, the range of D and E is, can be selected according to the following relation:

[0007] D is less than or equal to 30mm, and 5 is less than E and is less than or equal to 20 degrees;

[0008] 30mm is less than D and is less than or equal to 60mm, and 20 is less than E and is less than or equal to 30 degrees;

[0009] 60mm is less than D and is less than or equal to 120mm, and 30 is less than E and is less than or equal to 55 degrees;

[0010] 120mm is less than D and is less than or equal to 160mm, and 55 is less than E and is less than or equal to 70 degrees;

[0011] D is greater than 160mm, and 70 is less than E and is less than or equal to 85 degrees;

[0012] The smaller the line spacing L, the shorter the liquid injection time. However, the smaller the line spacing L, the more lines, which affects the production efficiency of the line process. In addition, the width D of the material area also affects the size of the line spacing L and the production efficiency. The value can be selected as follows:

[0013] D≤60mm,10mm<L≤20mm;

[0014] 60mm<D≤120mm,20mm<L≤30mm;

[0015] 120mm<D≤160mm,30mm<L≤40mm;

[0016] D>160mm,40mm<L;

[0017] The line width W is too small, which will result in a long liquid injection time. If the value is too large, it is easy to cause the battery performance to decline. The width is suitable for 200-300μm;

[0018] The smaller the line depth H, the longer the liquid injection time. The larger the value, the shorter the liquid injection time. However, it is easy to break the foil, which will result in performance decline. The selected value is 1 / 3T≤H≤2 / 3T.

[0019] Through the above mechanism: by laser on the negative plate to carve out the groove, so that the electrolyte has the infiltration route, which can greatly shorten the liquid injection time, and reduce the investment of the liquid injection equipment. The battery with good electrolyte infiltration has excellent cycle and rate charge-discharge performance.

[0020] Preferably, the manufacturing process of the positive plate is as follows:

[0021] Positive slurry: mix lithium iron phosphate or ternary material, etc. to form slurry;

[0022] Positive coating: coat the slurry on the positive foil, and form the positive material after drying the slurry. The foil has positive material on both sides, and finally forms the positive plate;

[0023] Positive rolling: roll the positive plate to the required thickness;

[0024] Positive cutting: cut the positive plate to the required width.

[0025] Preferably, the manufacturing process of the negative plate is as follows:

[0026] Mix graphite and other materials to form slurry;

[0027] Negative coating: coat the slurry on the negative foil, and form the negative material after drying the slurry. The foil has negative material on both sides, and finally forms the negative plate;

[0028] Negative roller compaction: the negative plate is rolled to the thickness required by the process;

[0029] Negative slitting: the negative plate is slitted to form a plate with a width of

[0030] Negative plate line marking: using a laser to mark lines on the negative material of the negative plate to form laser-marked lines.

[0031] Preferably, the manufacturing process of the roll core is:

[0032] The separator, the positive plate and the negative plate are wound, and after winding, the roll core is formed, and the laser-marked lines play a role of liquid guide holes after winding;

[0033] Roll core rubbing: rubbing the positive and negative electrode foils of the roll core;

[0034] Current collector disc welding and positive electrode rubber wrapping: welding the positive and negative current collector discs with the positive and negative electrodes of the roll core respectively, and wrapping the positive electrode with a high-temperature adhesive tape for one turn;

[0035] The roll core is placed into the shell.

[0036] Preferably, the shell is a steel shell, and the processing steps of the steel shell are:

[0037] Ultrasonic spot welding: ultrasonic welding the negative current collector disc of the roll core with the steel shell; and rolling the groove of the steel shell,

[0038] Liquid injection: liquid injection process is performed on the battery cell, and the electrolyte flows along the laser-marked lines in the direction indicated by the oblique arrow, and because the liquid injection is vertical, the electrolyte is affected by gravity and infiltrates into the battery cell in the direction indicated by the vertical arrow, greatly reducing the liquid injection time;

[0039] Cap welding: laser welding the positive current collector disc of the roll core with the cap; and then performing cap combining and sealing to obtain the battery;

[0040] Finally, the battery is cleaned, oiled and subjected to a hot shrinkage code spraying process.

[0041] The beneficial effects of the utility model are:

[0042] The utility model discloses: through the laser-marked groove on the negative plate, the electrolyte has the infiltration route, can greatly shorten the liquid injection time, reduces the investment of liquid injection equipment simultaneously, and the battery with good electrolyte infiltration has excellent cycle and rate charge-discharge performance. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 A large cylindrical lithium battery structure main view schematic drawing is provided for the utility model;

[0044] Figure 2The utility model provides a kind of large cylindrical lithium battery structure that adopts laser line technology is shown in the schematic diagram of top view.

[0045] Figure 3 The utility model provides a kind of large cylindrical lithium battery structure that adopts laser line technology is shown in the schematic diagram of laser line section view.

[0046] Figure 4 The utility model provides a kind of large cylindrical lithium battery structure that adopts laser line technology is shown in the schematic diagram of laser line rotation amplification.

[0047] In the drawing: 1, diaphragm; 2, positive sheet; 21, positive material; 22, positive foil; 3, negative sheet; 31, negative material; 32, negative foil; 4, laser line; 5, roll core. DETAILED DESCRIPTION

[0048] The utility model is further explained below in combination with specific embodiment.

[0049] Example 1

[0050] Reference Figures 1-4 In the embodiment, a kind of large cylindrical lithium battery that adopts laser line 4 technology is proposed, including diaphragm 1, positive sheet 2, negative sheet 3, laser line 4 and roll core 5, laser line 4 can be applied on positive sheet, also can be applied on negative sheet, can be engraved in single-sided sheet, also can be engraved in double-sided sheet;

[0051] Line angle E, between 0 ° to 90 °, its selection range, with the width D of material area of sheet, is directly related, the wider width D of material area, for pursuing liquid injection speed, line angle E is greater, the narrower width D of material area, for pursuing infiltration effect, line angle E is smaller, the range of D and E can be selected according to the following relationship:

[0052] D≤30mm,5 °<E≤20 °;

[0053] 30mm<D≤60mm,20 °<E≤30 °;

[0054] 60mm<D≤120mm,30 °<E≤55 °;

[0055] 120mm<D≤160mm,55 °<E≤70 °;

[0056] D>160mm,70 °<E≤85 °;

[0057] Line spacing L, the smaller its value, the shorter liquid injection time, but L is smaller, more line, affect the production efficiency of line process, and width D of material area, also can affect the size of line spacing L and production efficiency, its value can be selected according to the following:

[0058] D≤60mm,10mm<L≤20mm;

[0059] 60mm<D≤120mm,20mm<L≤30mm;

[0060] 120mm<D≤160mm,30mm<L≤40mm;

[0061] D>160mm,40mm<L;

[0062] The width of the score line W is too small, which will cause long injection time, and too large, which will easily cause the battery performance to decline, and the width of 200-300μm is appropriate;

[0063] The depth of the score line H is too small, which will cause long injection time, and too large, which will easily cause the battery performance to decline, and the width of 200-300μm is appropriate;

[0064] Through the above mechanism: by laser on the negative plate 3 groove, so that the electrolyte has the infiltration route, which can greatly shorten the injection time, and reduce the investment of the injection equipment, the electrolyte infiltration of the battery is good, and has excellent cycle and rate charge-discharge performance.

[0065] In this embodiment, the specific manufacturing process of the positive plate 2 is:

[0066] Positive slurry: mix lithium iron phosphate or ternary material, etc. to form slurry;

[0067] Positive coating: the slurry is coated on the positive foil 22, and the slurry is dried to form the positive material 21, and the foil has positive material 21 on both sides, and finally forms the positive plate 2;

[0068] Positive rolling: the positive plate 2 is rolled to the thickness required by the process;

[0069] Positive cutting: the positive plate 2 is cut to the width required by the process.

[0070] In this embodiment, the manufacturing process of the negative plate 3 is:

[0071] Mixing graphite and other materials to form slurry;

[0072] Negative coating: the slurry is coated on the negative foil 32, and the slurry is dried to form the negative material 31; the foil has negative material 31 on both sides, and finally forms the negative plate 3;

[0073] Negative rolling: the negative plate 3 is rolled to the thickness required by the process;

[0074] Negative cutting: the negative plate 3 is cut to the width of the plate;

[0075] Negative electrode sheet 3 scribing: using laser, scribe the negative electrode material 31 on the negative electrode sheet 3 to form the laser scribe 4.

[0076] In this embodiment, the manufacturing process of the roll core 5 is as follows:

[0077] The separator 1, the positive electrode sheet 2 and the negative electrode sheet 3 are wound, and after winding, the roll core 5 is formed, and the laser scribe 4 plays a role of a liquid guide hole after winding;

[0078] Roll core 5 rubbing: rubbing the positive and negative electrode foils 32 of the roll core 5;

[0079] Current collector disc welding and positive electrode rubberizing: welding the positive and negative current collector discs with the positive and negative electrodes of the roll core 5 respectively, and wrapping the positive electrode with high-temperature adhesive tape for one turn at the same time;

[0080] The roll core 5 is placed into the shell.

[0081] In this embodiment, the shell is a steel shell, and the processing steps of the steel shell are as follows:

[0082] Ultrasonic spot welding: ultrasonic welding the negative current collector disc of the roll core 5 with the steel shell; then rolling the groove of the steel shell,

[0083] Liquid injection: liquid injection process is performed on the battery cell, and the electrolyte flows along the laser scribe 4 in the direction indicated by the oblique arrow, because it is vertical injection, the electrolyte is affected by gravity and infiltrates into the battery cell in the direction indicated by the vertical arrow, greatly reducing the injection time;

[0084] Cap welding: laser welding the positive current collector disc of the roll core 5 with the cap; then performing cap combining and sealing to obtain the battery;

[0085] Finally, the battery is cleaned, oiled and heat-shrunk and coded.

[0086] Embodiment 2

[0087] Taking a 40140 type battery as an example, production is made;

[0088] 1. The lithium iron phosphate material is coated on the positive electrode foil 22, and after the slurry is dried, the rolling, slitting process is performed to obtain the electrode sheet; the coating width of the electrode sheet is 123.5 mm;

[0089] 2. The graphite material is coated on the negative electrode foil 32, and after the slurry is dried, the rolling, slitting process is performed to obtain the electrode sheet; the coating width of the electrode sheet is 126.5 mm, the total rolling thickness is 128 μm, and the thickness of the single-sided material is 61 μm;

[0090] 3. Negative electrode sheet 3 scribing: using laser, scribe negative electrode sheet 3, scribe both sides, depth 30pm±10pm, width 250pm±50pm, scribe interval 35pm±1pm, scribe angle 60°±2°;

[0091] 4. Winding: winding separator 1, positive electrode sheet 2, negative electrode sheet 3;

[0092] 5. Roll core 5 rubbing: rubbing positive and negative electrode foils 32 of roll core 5;

[0093] 6. Current collector disc welding and positive electrode rubber wrapping: welding positive and negative current collector discs with positive and negative electrodes of roll core 5 respectively, and wrapping positive electrode with high temperature rubber tape for one turn;

[0094] 7. Into shell;

[0095] 8. Ultrasonic spot bottom welding: ultrasonic welding of negative current collector disc of roll core 5 and steel shell;

[0096] 9. Steel shell rolling groove;

[0097] 10. Liquid injection: liquid injection process for the battery cell;

[0098] 11. Cap welding: laser welding of positive current collector disc of roll core 5 and cap;

[0099] 12. Cap combining and sealing;

[0100] 13. Cleaning, oiling and heat shrink code spraying process for the battery.

[0101] The following comparative examples use the same type of battery to compare different scribing schemes:

[0102]

[0103]

[0104] From the above results, comparative example 1 has no scribe, long liquid injection time and short cycle life, and in comparative example 8, although the liquid injection time is the shortest, the scribe interval is small, the production efficiency is low, and the cycle life is also not high.

[0105] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any skilled person in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A large cylindrical lithium battery using a laser scribing technique, comprising a separator (1), a positive electrode sheet (2), a negative electrode sheet (3), a laser scribe (4), and a jelly-roll (5), characterized in that, The laser scribing (4) is applied to the positive electrode plate and the negative electrode plate, and can be scribed on the single-sided plate and the double-sided plate; The scribing angle E is selected between 0° and 90°, and the selection range is directly related to the material area width D. The wider the material area width D, the greater the scribing angle E. The narrower the material area width D, the smaller the scribing angle E. The range of D and E is as follows, which can be selected according to the following relationship: D≤30mm, 5°<E≤20°; 30mm<D≤60mm, 20°<E≤30°; 60mm<D≤120mm, 30°<E≤55°; 120mm<D≤160mm, 55°<E≤70°; D>160mm, 70°<E≤85°; The scribing interval L is smaller, the liquid injection time is shorter, but the smaller L, the more scribing lines, which affects the production efficiency of the scribing process, and the material area width D also affects the size of the scribing interval L and the production efficiency. The value can be selected as follows: D≤60mm, 10mm<L≤20mm; 60mm<D≤120mm, 20mm<L≤30mm; 120mm<D≤160mm, 30mm<L≤40mm; D>160mm, 40mm<L; The scribing width W is 200-300μm; The scribing depth H is selected as 1 / 3T≤H≤2 / 3T.

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