CN109774126B

CN109774126B - Printing method for 3D printing of three-dimensional lithium ion battery and three-dimensional lithium ion battery

Info

Publication number: CN109774126B
Application number: CN201811643857.XA
Authority: CN
Inventors: 刘长勇; 许丰; 刘宴良
Original assignee: Shenzhen University
Current assignee: Shenzhen University
Priority date: 2018-12-29
Filing date: 2018-12-29
Publication date: 2021-09-07
Anticipated expiration: 2038-12-29
Also published as: CN109774126A

Abstract

The invention provides a device and a method for 3D printing of a three-dimensional lithium ion battery and the three-dimensional lithium ion battery, and belongs to the field of battery manufacturing. The device comprises a motion platform and a printing part arranged on the motion platform, wherein the printing part comprises 3 extruding devices with the same structure and a co-extrusion nozzle connected with the 3 extruding devices respectively, the extruding devices comprise extruding pieces for containing and extruding printing slurry, driving devices for driving the extruding pieces to extrude the slurry, and sensors which are arranged on the driving devices, are in contact with contact members and are used for controlling the speed of extruding the slurry by the extruding pieces; three flow passages respectively connected with 3 extrusion part output ports are arranged in the coextrusion nozzle, and coextrusion flow passages respectively communicated with the three flow passages are also arranged at the bottom end of the flow passage. The invention has the beneficial effects that: the three-dimensional lithium electronic battery with small overall dimension and high performance can be manufactured, the flexibility is high, and the cost is low.

Description

Printing method for 3D printing of three-dimensional lithium ion battery and three-dimensional lithium ion battery

Technical Field

The invention relates to battery manufacturing, in particular to a device for 3D printing of a three-dimensional lithium ion battery, a printing method based on the device and the three-dimensional lithium ion battery printed by the printing method.

Background

The co-extrusion type 3D printing is a new 3D printing mode and is mainly characterized in that a plurality of materials are printed by one nozzle, so that the materials are stacked and molded layer by layer from bottom to top, and devices which need multiple materials and have complex shapes can be manufactured. The traditional lithium ion battery comprises a button type battery, a column type battery, a square battery and the like, and is structurally characterized in that a negative electrode material and a positive electrode material are combined with a current collector in a coating mode and then are wound and laminated to form the lithium ion battery with a certain thickness. The structure is also a two-dimensional lithium ion battery. The structural defect that the two-dimensional lithium battery can not be kept away from is that the energy density of the battery can not be improved while the power density of the lithium ion battery is not influenced by increasing the height of an electrode. The three-dimensional lithium ion battery increases the specific surface area of the positive and negative electrodes without reducing the distance between the positive and negative electrodes of the lithium battery by designing the structural distribution of the high electrodes in a three-dimensional space, such as a columnar staggered array type, a sheet staggered type, a concentric array type and a random concentric type, and provides an idea for increasing the energy density of the battery while keeping the power density of the battery unchanged.

In the current report on the three-dimensional lithium ion battery, the used process is mainly to manufacture and mold the positive electrode and the negative electrode respectively, gel-state electrolyte is added into the gap, or the gel-state electrolyte is clamped at the two ends of the diaphragm and filled with electrolyte, and finally the lithium ion battery is formed by packaging. The three-dimensional lithium ion battery is manufactured by co-extrusion type 3D printing, and the manufacturing method has the advantages that the three-dimensional lithium ion battery is manufactured by developing a novel spray head suitable for the lithium ion battery material and a co-extrusion type 3D printing device and configuring the slurry suitable for printing, so that the anode, the cathode and the diaphragm slurry are integrally printed and formed in a complex structure.

There are few reports of using 3D printing to make three-dimensional lithium ion batteries by formulating battery-related pastes, and no 3D printing has been done by co-extrusion processes using multiple pastes. The reported positive and negative electrode paste of the battery is mostly prepared by adding a binder and a solvent into positive and negative electrode active substance powder, and the paste has low-temperature curing characteristic and low porosity of a printed electrode. The diaphragm paste is also the same, the ceramic powder is added into the polymer solution and is fully mixed for printing, and the polymer solvent has a high melting point and a low forming speed in a low-temperature environment, so that the co-extrusion 3D printing paste in the low-temperature environment needs to be added with a low-melting-point liquid phase to assist the solidification of the paste.

Therefore, the existing spray head, 3D printing equipment, anode and cathode slurry and diaphragm slurry cannot be used for manufacturing the co-extrusion printing three-dimensional lithium ion battery, and no process is available for replacing the co-extrusion 3D printing to manufacture the three-dimensional lithium ion battery so that the anode and the cathode are tightly combined with the diaphragm. Therefore, the existing coextrusion device and the anode, cathode and separator slurry are still to be improved and developed.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a device for 3D printing of a three-dimensional lithium ion battery, a printing method based on the device and the three-dimensional lithium ion battery printed by the printing method.

The device for 3D printing of the three-dimensional lithium ion battery comprises a motion platform and a printing part arranged on the motion platform, wherein the printing part comprises 3 extruding devices with the same structure and co-extrusion nozzles respectively connected with the 3 extruding devices, each extruding device comprises an extruding piece for containing and extruding printing slurry, a driving device for driving the extruding piece to extrude the slurry, and a sensor which is arranged on the driving device, is in contact with the extruding piece and is used for controlling the speed of extruding the slurry by the extruding piece; three flow passages respectively connected with 3 extrusion part output ports are arranged in the coextrusion nozzle, and coextrusion flow passages respectively communicated with the three flow passages are also arranged at the bottom end of the flow passage.

The invention is further improved, the moving platform comprises a base for fixing the printing component, a platform for placing the lithium electronic battery substrate, an X-axis movement servo motor for controlling the base to move along the X axis, a Y-axis movement servo motor for controlling the base to move along the Y axis, a Z-axis movement servo motor for controlling the platform to move along the Z axis and a rotating shaft servo motor for controlling the base to horizontally rotate along the longitudinal central axis.

The invention is further improved, the driving device is a motor with a vertically arranged motor shaft, a linear motion mechanism driven by the motor is arranged at the bottom of the motor, a pressure sensor is arranged on the linear motion mechanism, and the pressure sensor is connected with the top of the extrusion piece.

The invention is further improved, the extrusion part is a needle tube, the linear motion mechanism comprises a guide rail vertically arranged on the mounting plate and a slide block which is connected with a motor shaft and can move up and down on the guide rail, the pressure sensor is arranged on the slide block at the top end of a push rod of the needle tube, a bearing seat is arranged at the bottom of the guide rail, and the needle tube is fixed on the mounting plate through a shaft sleeve.

The invention is further improved, the co-extrusion nozzle is arranged on a device back plate connected with the extrusion device through a nozzle clamp, the co-extrusion nozzle is symmetrically arranged along a longitudinal central axis, the second flow channel and the co-extrusion flow channel are arranged on the longitudinal central axis, the first flow channel and the third flow channel are respectively arranged at the left side and the right side of the second flow channel and are converged with the second flow channel at the bottom end, the top ends of the first flow channel, the second flow channel and the third flow channel are respectively provided with a capillary tube, the co-extrusion nozzle is provided with a positioning structure, and the nozzle clamp is provided with a positioning block and a fixing block which are matched with the positioning structure.

The co-extrusion nozzle is further improved, a positioning right angle and a positioning hole are arranged on the co-extrusion nozzle, a nozzle positioning block is arranged at the position, corresponding to the positioning right angle, of the nozzle clamp, a pressing block hinged with the nozzle clamp and used for fixing the co-extrusion nozzle is further arranged on the nozzle clamp, and the positioning hole can limit the rotating position of the pressing block.

The invention is further improved, the first flow passage, the second flow passage and the third flow passage are square long grooves with the width and the depth being consistent to 0.3mm, and the co-extrusion flow passage is a square long groove with the width being 0.6mm and the depth being 0.3 mm.

The invention also provides a printing method based on the device, which comprises the following steps:

s1: preparing conductive silver colloid and diaphragm slurry 2, and preparing anode and cathode slurry and diaphragm slurry 1;

s2: setting a printing path and printing parameters;

s3: adding the diaphragm paste 2 into an extrusion piece connected with a middle flow channel, adding conductive silver adhesive into extrusion pieces connected with flow channels on two sides, and printing a conductive layer on a mica sheet, wherein the printing temperature is-10 to-20 ℃;

s4: arranging the tabs at corresponding positions;

s5: adding the diaphragm paste 1 into an extrusion piece connected with a middle flow passage, respectively adding the anode paste and the cathode paste into the extrusion pieces connected with the flow passages at two sides, and printing a material layer on the conducting layer, wherein the printing temperature is-10 to-20 ℃;

s6: freeze-drying the battery and then drying;

s7: and packaging the dried battery by using a soft package battery.

The three-dimensional lithium ion battery printed by the printing method comprises an insulated substrate, a printing battery arranged on the substrate, and lugs connected with the two poles of the printing battery through conductive silver adhesive, wherein the printed battery comprises more than 1 microbattery cell in series, wherein the microbattery cell comprises a conductive layer and a material layer disposed over the conductive layer, the conductive layer comprises a second diaphragm slurry layer arranged in the middle and conductive silver colloid layers arranged at two sides of the second diaphragm slurry layer, the material layer comprises a first diaphragm slurry layer arranged in the middle, and a positive electrode slurry layer and a negative electrode slurry layer which are arranged at the two sides of the first diaphragm slurry layer, the first diaphragm slurry layer and the second diaphragm slurry layer are arranged correspondingly, the positive electrode slurry layer and the conductive silver adhesive layer on the same side are arranged correspondingly, and the negative electrode slurry layer and the conductive silver adhesive layer on the same side are arranged correspondingly.

The invention is further improved, the printing path is S-shaped, and the whole shape of each micro battery unit is S-shaped curve and is closely arranged.

Compared with the prior art, the invention has the beneficial effects that: the three-dimensional lithium electronic battery with small overall dimension and high performance can be manufactured, and the battery has high flexibility and low cost.

Drawings

FIG. 1 is a schematic diagram of a printing element according to the present invention;

FIG. 2 is a schematic structural diagram of an embodiment of a motion platform;

FIG. 3 is a schematic view of the extrusion apparatus;

FIG. 4 is a schematic view of a showerhead fixture and a co-extrusion showerhead;

FIG. 5 is a schematic view of the internal structure of the coextrusion nozzle;

FIG. 6 is a flow chart of a method of the present invention;

fig. 7 is a partial schematic view of a three-dimensional lithium-ion battery;

fig. 8 is a schematic cross-sectional view of the electrode material layer, the conductive layer, the tab and the mica sheet as viewed in the direction of the arrows in fig. 7.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples.

As shown in fig. 1-5, the device for 3D printing a three-dimensional lithium ion battery according to the present invention includes a moving platform and a printing component 1 disposed on the moving platform, where the printing component 1 includes an extruding device 101 and a nozzle clamping device 102 with the same 3-way structure, the extruding device 1 includes an extruding member for receiving and extruding a printing paste, a driving device for driving the extruding member to extrude the paste, and a sensor disposed on the driving device, in contact with a contact member, for controlling a speed of extruding the paste by the extruding member; three flow channels respectively connected with 3 extrusion piece output ports are arranged in the co-extrusion nozzle 1028, and co-extrusion flow channels respectively communicated with the three flow channels are also arranged at the bottom ends of the flow channels.

As shown in fig. 2, as an embodiment of the present invention, the moving stage of this example includes a vertically disposed mounting plate 404 and a Z-axis stage 405 that fix the printing part, a Z-axis movement servo motor 406 that controls the printing part to move along the Z-axis, disposed below the Z-axis stage 405, an X-axis movement servo motor 401 that controls the printing part to move along the X-axis, a Y-axis movement servo motor 402 that controls the printing part to move along the Y-axis, and a rotation axis servo motor 403 that controls the printing part to horizontally rotate along a longitudinal motor axis.

The whole mechanical structure of the embodiment has 7 degrees of freedom in total, and the whole mechanical structure is controlled by using the motor. The three-dimensional paste extruding machine comprises 3 degrees of freedom for controlling the XYZ movement of a printing component, 3 degrees of freedom for controlling 3 extruding pieces to extrude paste on the printing component and 1 degree of freedom for controlling the printing component to rotate.

The Y-axis motion servomotor 402 of the present example is mounted on the X-axis motion servomotor 401, the rotary axis servomotor 403 is mounted on the Y-axis motion servomotor 402, the mounting plate 404 is connected to the rotary axis servomotor 402, and the Z-axis stage 405 is connected to the Z-axis motion servomotor 406. Wherein the carrying board 404 of the printing part 1 is connected with the printing part 1, and the printing substrate is placed on the Z-axis platform 405. When 3D printing is carried out, paste to be printed is added into the needle tube 1016 and placed on the printing component 1, the XYZ-axis movement servo motor is controlled to determine a printing path, the motor in the printing component 1 is controlled to control the paste extrusion speed, and the rotation of the rotary shaft servo motor control core component is controlled to determine the relative position of each paste. Required slurry is printed through the co-extrusion type 3D printing device, and multiple kinds of slurry are extruded together to be integrally formed.

The printing component of the embodiment has 3 degrees of freedom in total, and 3 spray heads are respectively controlled to extrude the slurry. The slurry used therein is required to have superior fluidity and the viscosities of the three slurries used are required to be consistent. Because the line width of the slurry extruded by the nozzle is expanded with the substrate, a margin is required to be reserved when a printing path is designed. The mica sheet with good flexibility and thickness of 0.01mm is used as a printing substrate, so that the insulation performance of the battery can be guaranteed while the printing material is loaded.

As shown in fig. 1 and 3, the driving device of this example is a screw motor 1011 with a vertically arranged motor shaft, and is fixed on a rear plate 1021 of the device through a motor base 1012, a linear motion mechanism 1014 driven by the screw motor 1011 is arranged below the motor, a pressure sensor 1018 is arranged on the linear motion mechanism 1014, and the pressure sensor 1018 is connected with the top of the extrusion piece.

Specifically, the extrusion member in this example is a needle tube 1016, the needle tube 1016 of the extrusion device 101 is connected to a flow channel of the co-extrusion nozzle 1028 on the nozzle holder 102 through an air tube, the slurry is extruded to the air tube through the extrusion device 101, and the slurry is extruded from the co-extrusion nozzle 1028 connected to the air tube. Also, the pressure sensor 1018 is disposed at the tip of the pushrod within the syringe 1016.

The linear motion mechanism comprises a vertically arranged guide rail connected with a motor shaft and a slide block capable of moving up and down on the guide rail, the pressure sensor is arranged on the slide block at the top end of a push rod of the needle tube, a bearing seat 1015 is arranged at the bottom of the guide rail, and the needle tube 1016 is fixed on the rear plate 1021 of the device through a T-shaped shaft sleeve 1017. The screw rod stepping motor 1011 is controlled by a control card to move, when the device works, the screw rod drives the screw rod nut 1013 to push the slide block arranged on the linear guide rail to move forwards, and because the M3 knurled screw 1019 fixes the pressure sensor 1018 on the slide block to move downwards together, the pressure is transmitted to the push rod of the needle tube 1016 to extrude the slurry in the needle tube 1016. Wherein the linear motion mechanism conducts pressure, the bearing block 1015 secures the lead screw, and the T-shaped bushing 1017 is used to secure the needle 1016 to the device back plate 1021.

As shown in fig. 3, the extruding device of the co-extrusion 3D printing device is composed of a lead screw stepping motor, a motor base, a lead screw nut, a linear motion mechanism, a bearing seat, a needle tube, a T-shaped shaft sleeve, a pressure sensor, and M3 knurled screws. Wherein the fasteners are not identified in the figures. The screw rod stepping motor is controlled by the control card to move, when the device works, the screw rod drives the screw rod nut to push the sliding block arranged on the linear guide rail to move forwards, and because the pressure sensor is fixed on the sliding block by the M3 knurled screw to move downwards together, pressure is transmitted to the needle tube to extrude slurry in the needle tube. The motor base plays a role in fixing the motor, the linear motion mechanism conducts pressure, the bearing block fixes the lead screw, and the T-shaped shaft sleeve fixes the needle tube.

As shown in fig. 4, the nozzle holder 102 includes a co-extrusion nozzle 1028 and a nozzle holder 1029, the co-extrusion nozzle 1028 is disposed on a rear plate 1021 of the apparatus connected to the extrusion apparatus 101 via the nozzle holder 1029, an upper fastening plate 1023 and a lower fastening plate 1024 are disposed on the rear plate of the apparatus in this example, the nozzle holder 1029 is fixed between the upper fastening plate 1023 and the lower fastening plate 1024 via M4 knurled screws 1022, and the nozzle holder 1029 is further positioned on the lower fastening plate 1024 via M5 knurled screws 1025. The press block 1027, the nozzle positioning block 1026 and the M3 knurled screw position the co-extrusion nozzle 1028 so that the co-extrusion nozzle 1028 is held in close contact with the nozzle holder 1029.

As shown in fig. 5, the internal structure of the co-extrusion nozzle 1028 in this embodiment mainly comprises a first flow channel 10281, a second flow channel 10282, a third flow channel 10283, and a co-extrusion flow channel 10284, wherein a capillary 10286 is connected to the top ends of the first flow channel 10281, the second flow channel 10282, and the third flow channel 10283 respectively for drainage. The co-extrusion nozzle 1028 is symmetrically arranged along a longitudinal central axis, the second flow passages 10282 and the co-extrusion flow passages 10284 are arranged on the longitudinal central axis, and the first flow passages 10281 and the third flow passages 10283 are respectively arranged at the left and right sides of the second flow passages 10282 and are merged with the second flow passages 10282 at the bottom end. The bottom of the co-extrusion nozzle 1028 is provided with a nozzle 10285, two sides of the nozzle 10285 are respectively and symmetrically provided with two positioning right angles, the co-extrusion nozzle 1028 is respectively and symmetrically provided with two positioning holes, and the nozzle clamp 1029 is provided with a nozzle positioning block 1026 matched with the positioning right angles. The nozzle clamp 1029 is further provided with a pressing block 1027 which is hinged with the nozzle clamp 1029 and used for fixing the co-extrusion nozzle 1028, and the positioning hole 10287 can limit the rotating position of the pressing block 1027.

The co-extrusion nozzle 1028 in this example is made of quartz. The first flow channel, the second flow channel and the third flow channel are square long grooves with the width and depth being consistent to 0.3mm, and the co-extrusion flow channel is a square long groove with the width being 0.6mm and the depth being 0.3 mm. In the embodiment, three square long grooves with the same width and depth of 0.3mm and one square groove with the width of 0.6mm and the depth of 0.3mm are processed by laser, and then the closed holes are formed by bonding. The coextrusion is completed by the final confluence of three micro flow channels into a coextrusion flow channel.

As shown in fig. 6, the present invention is based on the printing device, and before printing, a printing path and related parameters, such as flow rates of the respective flow channels, need to be set. After the setting is completed, the printing process of this example includes the steps of:

step 301, preparing conductive silver colloid and diaphragm slurry 2;

the conductive silver paste of this example was used by mixing an epoxy resin, an amine-based curing agent, and a silver flake powder at a ratio of 80:16: 4. The diaphragm slurry 2 is prepared from boron nitride powder, polyvinylidene fluoride-hexafluoropropylene, dimethylformamide and 1,4 dioxane which are ground into fine powder of 1-10 mu m, wherein the boron nitride powder and the polyvinylidene fluoride-hexafluoropropylene are in a mass ratio of 6:1 or 5:1, the dimethylformamide and the 1,4 dioxane are in a volume ratio of 1:1, the viscosity of the conductive silver colloid is matched, and the solid phase is not lower than 6g:10ml compared with liquid. Heating to form colloid, mixing the materials, vacuum stirring to mix the slurry, suction filtering, and filtering to obtain large particles easy to block the nozzle. The viscosity of the slurry is adjusted through the solid-phase liquid-phase content of the slurry, and the two materials with the same viscosity are selected for printing through rheometer test.

302, preparing anode and cathode slurry and diaphragm slurry 1;

wherein the used anode and cathode material powder and the boron nitride powder are ground into fine powder with the particle size of 1-10 mu m, and the slurry does not block the spray head when the fluidity of the powder is increased. The anode slurry is composed of anode material powder, a thickening agent, a conductive agent, deionized water and 1,4 dioxane, and the cathode material is composed of cathode material powder, a thickening agent, a conductive agent, deionized water and 1,4 dioxane which are mixed according to a certain mass fraction. Wherein the mass percent of the electrode material powder (anode material powder or cathode material powder) is 10-40%, the mass percent of the thickening agent is 2-5%, the mass percent of the conductive agent is 2-5%, the mass percent of the deionized water is 25-40%, and the mass percent of the 1,4 dioxane is 25-40%. The diaphragm slurry 1 is composed of boron nitride powder, polyvinylidene fluoride-hexafluoropropylene, dimethylformamide and 1,4 dioxane in a mass ratio of 6:1 or 5:1, and the dimethylformamide and the 1,4 dioxane in a volume ratio of 1:1, and is matched with the viscosity of the positive and negative electrode slurry, and the solid phase of the slurry is not higher than 8g:10ml compared with liquid. Heating to form colloid, mixing, vacuum stirring to mix the slurry, suction filtering, and filtering to obtain large particles easy to block the nozzle. And selecting the three materials with equivalent viscosity for printing through rheometer test.

Step 303, adding the diaphragm paste 2 into an extrusion piece connected with a middle flow passage, adding conductive silver adhesive into needle tubes connected with flow passages at two sides, printing a conductive layer on a mica sheet, and printing at a low temperature of-10 to-20 ℃;

304, arranging the tabs at corresponding positions, coating conductive silver adhesive on the corresponding positions of the tabs, and arranging and welding the tabs above the conductive silver adhesive;

305, adding the diaphragm paste 1 into an extrusion piece connected with a middle flow passage, respectively adding the positive electrode paste and the negative electrode paste into needle tubes connected with the flow passages at two sides, printing a material layer on the conducting layer, and printing at a low temperature of-10 to-20 ℃ to solidify and form a liquid phase in the paste;

and 306, drying the battery after freeze drying, placing the printed three-dimensional lithium electronic battery in a freeze dryer, removing the solidified organic solvent and deionized water distributed in the electrode slice to manufacture a porous electrode and a diaphragm, wherein the pores of the porous electrode and the diaphragm are helpful for filling electrolyte. Drying to accelerate the curing of the conductive silver adhesive;

and 307, packaging the soft package battery, and packaging the printed three-dimensional lithium ion battery by using a packaging process of the soft package battery to complete the manufacture of the three-dimensional lithium ion battery.

Generally, the printing of the three-dimensional battery is mainly divided into two steps, the first step is the printing of a conducting layer, the printed conducting layer is used for replacing a traditional current collector to enable the manufacturing to be more flexible, the second step is the printing of a material layer, and the lithium battery with a complex structure is manufactured through 3D printing of electrode materials. However, in the process of extruding the material by using the co-extrusion method, if the path has a certain angle after bending when the printing path is designed, the co-extrusion nozzle 1028 needs to rotate by a corresponding angle to extrude the paste, so that the paste does not intersect and cause a short circuit. Therefore, the co-extrusion nozzle 1028 needs to rotate along the designed path, and the rotation is realized by the rotating shaft servo motor 403 on the moving mechanism, so that the cross overlapping of the slurry is avoided. When the conductive layer is printed, the conductive silver paste is placed in the needle tubes at two sides, and the diaphragm paste 2 is placed in the needle tube at the middle for co-extrusion printing. The conductive silver paste printed on both sides serves as a current collector and the diaphragm paste 2 separates the positive and negative electrodes, so that the battery is not short-circuited. When the material layer is printed, anode and cathode slurry is placed in needle tubes at two sides, the diaphragm slurry 1 is placed in the needle tube in the middle, the printing material layer is placed on the conducting layer, the anode and cathode slurry is sequentially placed on two non-interfering conducting silver adhesive lines to form an anode and a cathode, and the diaphragm slurry 1 is placed on the diaphragm slurry 2 to serve as an insulating layer. The tremella is bonded and pressure-welded with the corresponding positive and negative conductive silver adhesive wires through the conductive silver adhesive and respectively serves as positive and negative leads.

As shown in fig. 7 and 8, the three-dimensional lithium ion battery 2 printed by the printing method of the present invention comprises an insulating mica sheet 201, a printing battery disposed on the mica sheet 201, and tabs 204 connected to two poles of the printing battery via conductive silver paste, wherein the printing battery comprises a plurality of series-connected microbattery cells, wherein the microbattery cells comprise a conductive layer 203 and a material layer 202 disposed above the conductive layer 203, the conductive layer 203 comprises a second membrane paste layer 2031 disposed in the middle and conductive silver paste layers 2032 disposed at two sides of the second membrane paste layer 2031, the material layer 202 comprises a first membrane paste layer 2022 disposed in the middle and a positive electrode paste layer 2021 and a negative electrode paste layer 2023 disposed at two sides of the first membrane paste layer 2022, wherein the first membrane paste layer 2022 and the second membrane paste layer 2031 are disposed correspondingly, the positive electrode paste layer 2021 is disposed corresponding to the conductive silver paste layer 2032 on the same side, and the negative electrode paste layer 2023 is disposed corresponding to the conductive silver paste layer 2032 on the same side. The printing path of the micro-battery units is S-shaped, the whole shape of each micro-battery unit is S-shaped curve and is tightly arranged, so that the space can be fully utilized, the same materials can be squeezed together in the printing process, the forming of the final battery cannot be influenced, the flexibility of the battery can be increased through the distributed printing design, and the battery cannot be broken or lose efficacy after being packaged and bent. And each micro battery is connected in series to achieve the purpose of obtaining a high-capacity battery.

As shown in fig. 8, the tab 204 at one end is connected to the positive and negative electrode silver conductive adhesive wires through a layer of conductive silver adhesive 2033 for electrical conduction.

The above-described embodiments are intended to be illustrative, and not restrictive, of the invention, and all changes that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims

The printing method for 3D printing of the three-dimensional lithium ion battery is characterized by comprising the following steps: the printing method of the 3D printing three-dimensional lithium ion battery is realized based on a 3D printing three-dimensional lithium ion battery device, the 3D printing three-dimensional lithium ion battery device comprises a motion platform and a printing part arranged on the motion platform, the printing part comprises 3 extruding devices with the same structure and co-extrusion nozzles respectively connected with the 3 extruding devices, the extruding device comprises an extruding piece for containing and extruding paste for printing, a driving device for driving the extruding piece to extrude the paste, and a sensor which is arranged on the driving device, is in contact with the extruding piece and is used for controlling the speed of extruding the paste by the extruding piece; the printing method for the 3D printing three-dimensional lithium ion battery comprises the following steps of:

s1: preparing conductive silver colloid and diaphragm slurry 2, and preparing anode and cathode slurry and diaphragm slurry 1;

s2: setting a printing path and printing parameters;

s3: adding the diaphragm paste 2 into an extrusion piece connected with a middle flow channel, adding conductive silver adhesive into extrusion pieces connected with flow channels on two sides, and printing a conductive layer on a mica sheet, wherein the printing temperature is-10 to-20 ℃;

s4: arranging the tabs at corresponding positions;

s5: adding the diaphragm paste 1 into an extrusion piece connected with a middle flow passage, respectively adding the anode paste and the cathode paste into the extrusion pieces connected with the flow passages at two sides, and printing a material layer on the conducting layer, wherein the printing temperature is-10 to-20 ℃;

s6: freeze-drying the battery and then drying;

s7: and packaging the dried battery by using a soft package battery.
2. The printing method according to claim 1, wherein: the motion platform comprises a base for fixing the printing component, a platform for placing a lithium electronic battery substrate, an X-axis motion servo motor for controlling the base to move along an X axis, a Y-axis motion servo motor for controlling the base to move along a Y axis, a Z-axis motion servo motor for controlling the platform to move along a Z axis and a rotating shaft servo motor for controlling the base to horizontally rotate along a longitudinal central shaft.
3. The printing method according to claim 1 or 2, characterized in that: the driving device is a motor with a motor shaft vertically arranged, a linear motion mechanism driven by the motor is arranged at the bottom of the motor, a pressure sensor is arranged on the linear motion mechanism, and the pressure sensor is connected with the top of the extrusion piece.
4. A printing method according to claim 3, characterized in that: the extrusion piece is a needle tube, the linear motion mechanism comprises a vertical guide rail arranged on the mounting plate and a sliding block which is connected with a motor shaft and can move up and down on the guide rail, the pressure sensor is arranged on the sliding block at the top end of a push rod of the needle tube, a bearing seat is arranged at the bottom of the guide rail, and the needle tube is fixed on the mounting plate through a shaft sleeve.
5. The printing method according to claim 1 or 2, characterized in that: the co-extrusion nozzle is arranged on a device rear plate connected with the extrusion device through a nozzle clamp, the co-extrusion nozzle is symmetrically arranged along a longitudinal central axis, the second flow channel and the co-extrusion flow channel are arranged on the longitudinal central axis, the first flow channel and the third flow channel are respectively arranged on the left side and the right side of the second flow channel and are converged with the second flow channel at the bottom end, capillaries are respectively arranged at the top ends of the first flow channel, the second flow channel and the third flow channel, a positioning structure is arranged on the co-extrusion nozzle, and a positioning block and a fixing block matched with the positioning structure are arranged on the nozzle clamp.
6. The printing method according to claim 5, wherein: the co-extrusion nozzle is characterized in that a positioning right angle and a positioning hole are formed in the co-extrusion nozzle, a nozzle positioning block is arranged at the position, corresponding to the positioning right angle, of the nozzle clamp, a pressing block which is hinged to the nozzle clamp and used for fixing the co-extrusion nozzle is further arranged on the nozzle clamp, and the positioning hole can limit the rotating position of the pressing block.
7. The printing method according to claim 5, wherein: the first flow channel, the second flow channel and the third flow channel are square long grooves with the width and depth being consistent to 0.3mm, and the co-extrusion flow channel is a square long groove with the width being 0.6mm and the depth being 0.3 mm.
8. The three-dimensional lithium ion battery printed according to any one of claims 1 to 7, wherein: including insulating base plate, the printing battery of setting on the base plate, the utmost point ear that links to each other with the printing battery two poles of the earth through conductive silver adhesive, wherein, printing battery includes the little battery unit of the series connection more than 1, wherein, little battery unit includes the conducting layer and sets up the material layer in the conducting layer top, the conducting layer is including setting up the second diaphragm thick liquids layer in the middle and setting up the conductive silver adhesive layer in second diaphragm thick liquids layer both sides, the material layer is including setting up the first diaphragm thick liquids layer in the middle and setting up anodal thick liquids layer and the negative pole thick liquids layer in first diaphragm thick liquids layer both sides, wherein, first diaphragm thick liquids layer and second diaphragm thick liquids layer correspond the setting, the conductive silver adhesive layer of anodal thick liquids layer and homonymy corresponds the setting, the negative pole thick liquids layer corresponds the setting with the conductive silver adhesive layer of homonymy.
9. The three-dimensional lithium ion battery of claim 8, wherein: the printing path is S-shaped, and the whole shape of each micro-battery unit is S-shaped curve and is closely arranged.