Preparation method of dry-method electrode pole piece, electrode pole piece and battery cell

An electrode pole piece and dry method technology, which is applied in the field of battery preparation, can solve the problems of self-supporting membrane hole edges, uneven feeding, and excessive material volume, and achieve the goal of improving the poor uniformity of the membrane and improving the quality and performance. Effect

Active Publication Date: 2021-12-31

SVOLT ENERGY TECHNOLOGY CO LTD

2 Cites 1 Cited by

AI-Extracted Technical Summary

Problems solved by technology

[0003] However, this technology is still in the initial stage of research and development, and there are many problems that need to be solved urgently, such as in the preparation process of the pole piece, such as the degree of fiberization of the binder in the mixing stage Insufficient, then the self-supporting film that can be forme...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine

Method used

2, electric core is first clamped up and down with rubber pad, then clamps rubber pad up and down with glass plate, clamps and fixes with dovetail clamp at last, makes pole piece film and pole piece closely fit, then puts into oven high temperature Baking can play the role of hot pressin...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine

Abstract

The invention provides a preparation method of a dry-method electrode pole piece, an electrode pole piece and a battery cell. The preparation method of the dry-method electrode pole piece comprises the following steps of preparing a fibrillated mixed material from raw material powder, stirring and sieving the mixed material to obtain pole piece powder, and processing the pole piece powder to obtain the electrode pole piece. According to the preparation method of the dry-method electrode pole piece, the material fibration degree before feeding can be regulated and controlled by stirring and sieving the mixed material, so that the thickness of a rolled film is regulated and controlled, and the problems of poor uniformity and poor neatness of the film are solved, so that the electrode pole piece prepared by the method is used for preparing a battery cell, and the quality and the performance of the battery cell are favorably improved.

Application Domain

Electrode rolling/calenderingLi-accumulators +1

Technology Topic

Composite materialBattery cell +1

Image

Examples

Experimental program(2)
Comparison scheme(2)

Example Embodiment

[0031] The present invention relates to a method of preparing a dry electrode plate comprising a step of preparing a mixed material having a fibrillation of a raw material powder, a mixture, a mixture, a prefraction, and a pole powder powder The step of obtaining the electrode plate after processing is processed.

[0032] The method of preparing the dry electrode plate of the present invention has high degree of fibrosis to which the material fibrosis obtained is high after hyperi-high-speed agitation or polishing, and it is uniformly pinched, and this high fibrosis is gently pinched. The material is first slowly stir, and then quickly agitated, and the agglomerate of small particles can be obtained. The material is filtered, and the screening of the particles after the screening can be directly entered the roller press. Self-supporting film strength is better, you can directly collect.

[0033] Based on the above design idea, the method of preparing the dry electrode plate of the present embodiment includes the following steps:

[0034] 1. Put the battery active substance, conductive agent, and binder in turn into the mixing machine.

[0035] It should be understood herein that in this step, corresponding to the positive electrode or the negative electrode, the active material applied is different, so the positive electrode plate and the negative electrode plate should be prepared, and the aforementioned battery active substance comprises a positive electrode active material. Negative electrode active substance.

[0036] Specifically, the positive electrode active substance includes, but is not limited to, at least one of lithium cobaltate, lithium manganese acid, lithium nickel acid, three-dimensional nickel-manganese acid, phosphate, that is, the positive electrode active material can be two Order or more or more mixtures.

[0037] The negative electrode active substance includes, but is not limited to, at least one of graphite, silicon, silicon oxide, lithium silicon alloy, and lithium powder, that is, the negative electrode active material may be two or more mixtures thereof.

[0038] Further, the conductive agents in this step include, but are not limited to, at least one of acetylene black, super-p (ie, small particle conductive carbon black), carbon nanotubes, carbon fibers, Cos black, graphite conductive agent, graphene, That is, the conductive agent can be two or more mixtures thereof.

[0039] The binder is a fibrous polymer including, but not limited to, at least one of polytetrafluoroethylene, butyrene rubber, polypropylene, and polyethylene, EVA (ethylene-vinyl acetate copolymer), i.e., a binder Two or more mixtures are mixed.

[0040] 2, the resulting mixture obtained in step 1 is super high speed (≥15000 rpm) to a high speed (≥15000 rpm) stirring shear or abrasive fibrosis to obtain high fibrosis mixture A.

[0041] 3, the mixture A obtained by step 2 is "binder fibrosis regulation" process, first mixed with a stirrer, slowly stir, and then stirred, then the stirred material is sieved, resulting in fibrosis-regulated material B .

[0042] In this step, the mixture is stirred by a mixer, preferably, the mixer of the stirrer is as follows: the stirring shaft is provided with two groups of meniscus-shaped blades, and the two sets of blades are arranged along the axial direction of the stirring shaft, and two sets of blades Displaced 90 ° arrangement, and each set of blades included two blades opposite to both sides of the agitating shaft, i.e., two blades of each group are 180 °. In addition, the mixing paddles can of course also use other structures, such as single / double screw, one or three-leaf, dispersed discs, etc.

[0043] As a preferred embodiment, the mixing machine of the agitator is 0.6 to 0.99: 1, preferably from 0.8 0.99: 1, preferably from 0.8 to 0.95 to achieve a preferred stirring effect.

[0044] When agitation is specifically stirred, stirring is made first, in particular, the mixed material has a slow stirring rate of 500 to 1000 rpm, and the mixture of mixed materials is 1 to 5 min; the rapid stirring speed of the mixed material is 1500. ~ 3000 rpm, the rapid stirring time of the mixed material is 1 to 3 min to increase the performance of the prepared plate membrane.

[0045] Further, in this step, the number of screens of the mixed material sieve is 1 to 100 mesh, preferably 8 to 40 mesh, such as 10 mesh, 20 mesh, 30 mesh, etc., to further improve the prepared polar membrane. performance.

[0046] 4. Adjust the roller gap, feed the material B to the roller press, and the roller is pressed to obtain a continuous self-supporting pole film, and can be directly retracted.

[0047] 5. The collector after retracting the tensile membrane roller is pressed to obtain the corresponding positive electrode pole or negative pole roll.

[0048] 6, die cutting machine, obtain a positive electrode plate or negative electrode plate of a suitable size.

[0049] The method of preparing the dry electrode plate of the present invention can improve the material cake due to the excessive degree of fibrosis in the dry electrode, resulting in unevenness, and the film Have a problem, and the edge is not equal.

[0050] In the preparation method of the above, it is mainly through the "binder fibrosis regulation" process, and the first mixer is agitated, and the bulk material is dispersed into small particulate materials, and then the particles of different particles of different particles are obtained by the sieve, according to the roller The thickness required for the pressing pole piece is selected from the screen sieve, the larger the thickness of the pole, the smaller the number of screens.

[0051]Preparing a dry electrode pole pieces of the present invention, by stirring and sieving mixed feed, can regulate the intake of the present material fibrosis before the material, and further adjust the roll out of the film thickness, to improve the film uniformity is poor, neat problem of poor, the preparation of such cell electrode prepared by the method of pole pieces, help improve the quality and performance of batteries.

[0052] The present invention further relates to an electrode pole pieces, the pole pieces of the electrode as the electrode dry pole piece preparation was obtained.

[0053] Further, the present invention relates to a cell, the cell is pasted with a pole piece comprising a film, and is stacked state of the plurality of electrodes as pole pieces. It is noted that the pole piece film is pasted after the electrode pole piece, using jig for baking treatment.

[0054] Specifically, the jig comprising a bonded rubber layer is pasted on both sides of the electrode film pole piece pole piece, bonded to the glass layer on the outside of each rubber layer and the glass layer sandwiched between the clamping means.

[0055] As a preferred embodiment, the thickness of the rubber layer is preferably 1-3mm, in the longitudinal direction, the rubber layer on both sides of the core are larger than the electrical 1-3mm, in the width direction of the rubber layer on both sides of the core are larger than the electrical 1-3mm. Note that here, the rubber layer may be replaced by other materials having similar properties or action, as it may be a silicone layer, a plastic layer.

[0056] Further, during the preparation of the cell, the cell temperature baking temperature may be 80-200 deg.] C, preferably 100-150 deg.] C, as it may be 100 ℃, 120 ℃, 135 ℃, 150 ℃.

[0057] The method of preparation of the cell according to the invention, comprises the steps of preparing:

[0058] 1, the pole piece film cut to the appropriate size and then laminated, adhesive tape, to obtain batteries.

[0059] 2, the first cell under the pad sandwiched rubber, rubber pad sandwiched between the upper and lower glass sheet and then, finally fixed clamp onto the dovetail, so that the pole pieces and the pole pieces of the film in close contact with, and then placed in an oven at high temperature baking, It can play a role in pressing the electrode film and the sheet close contact with the pole pieces, the pole pieces to reduce the interface resistance.

[0060] 3, a welding tab, the top side of the seal, the injection, the package, i.e., monolithic finished batteries.

[0061] 4, will produce a good electrical centering jig: first sandwiched with the rubber mat and glass plate sandwich, and finally fixed clamp onto the dovetail pressure acts to uniformly dispersed, with the pole piece pole piece film is tightly bonded action This can reduce the interface resistance of the pole piece, can give full play to the performance of the battery, to improve battery performance test.

[0062] Preparation Preparation electrode pole piece of the present invention and batteries, safe, easy-to-zoom, a method suitable for industrial applications, will help promote the development of new energy industries, has broad application prospects. After cell produced by this method, by applying the above electrode pole pieces, but also improve the internal resistance of the battery is too large monolithic problems, and improve the quality and performance of batteries.

Example Embodiment

[0063] Example 1

[0064] The positive electrode active material NCM811 (NCM representing the main component of nickel, cobalt, manganese, and 811 is represented by the ratio of the three components of 8: 1: 1) accounting for 92% by weight, the proportion of the conductive agent, 2% by weight of SP activated carbon accounted for 2% by weight of the conductive agent, the binder proportion accounted for 4% by weight of PTFE, the negative electrode active material accounted for 97% by weight Gr, the proportion by weight of the conductive agent 1% SP, accounted for 2% by weight of PTFE binder the mixing proportion and fibrosis.

[0065] The height of the obtained material for fibrosis "binder fibrosis regulation process", i.e. material into the meniscus slow stirring blade type mixer for 3 minutes, with rapid stirring for 1 minute, then the material is sieved through 18 mesh screen after the regulation of the sieved material obtained.

[0066] After the regulation of the material into the feed roll press, to obtain self-supporting film, after fluid collection mash paste to a thickness, and positive and negative electrode sheets were cut, laminated, obtained batteries, electrical respectively on both sides of the core after the rubber pad, a glass plate, using dovetail clips, high-temperature baking at 120 ℃ 12 hours, then the normal welding process, the top canonized, injection, to give a final seal monolithic batteries, electrical respectively on both sides of the core rubber mats, a glass plate, using the chemical conversion and subsequent precharge rate after the test volume dovetail clips.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine

Login to view more

PUM

Property	Measurement	Unit
Mesh	1.0 ~ 100.0	mesh
Thickness	1.0 ~ 3.0	mm
tensile		MPa
Particle size		Pa
strength	10

Description & Claims & Application Information

We can also present the details of the Description, Claims and Application information to help users get a comprehensive understanding of the technical details of the patent, such as background art, summary of invention, brief description of drawings, description of embodiments, and other original content. On the other hand, users can also determine the specific scope of protection of the technology through the list of claims; as well as understand the changes in the life cycle of the technology with the presentation of the patent timeline. Login to view more.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine

Login to view more

Classification and recommendation of technical efficacy words

Improve quality and performance

Preparation method of dry-method electrode pole piece, electrode pole piece and battery cell

AI-Extracted Technical Summary

Problems solved by technology

Method used

Abstract

Image

Examples

Example Embodiment

Example Embodiment

PUM

Description & Claims & Application Information

Similar technology patents

Pressing type bean pulp smashing device

Multi-cavity PVD-RTA mixed film deposition system

A kind of heat treatment method of copper chromium alloy for high voltage switch

Gas distribution and diffusion plate and plasma processor

Sending-out mechanism of fertilizer discharger of plant protection fertilizer spraying machine

Classification and recommendation of technical efficacy words

Switching method of built-in antenna and exposed antenna of FM receiver as well as terminal thereof

Mobile Internet-based home-school interaction teaching system

Soldering method of conducting ring of motor rotor

Quenching process of H13 steel aluminum alloy die-casting die

Machine for blowing molding articles such as containers