CN117174830A - Preparation methods of negative electrode slurry, negative electrode sheet and battery - Google Patents
Preparation methods of negative electrode slurry, negative electrode sheet and battery Download PDFInfo
- Publication number
- CN117174830A CN117174830A CN202310732169.5A CN202310732169A CN117174830A CN 117174830 A CN117174830 A CN 117174830A CN 202310732169 A CN202310732169 A CN 202310732169A CN 117174830 A CN117174830 A CN 117174830A
- Authority
- CN
- China
- Prior art keywords
- negative electrode
- slurry
- silicon
- electrode slurry
- mixing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000011267 electrode slurry Substances 0.000 title claims abstract description 34
- 238000002360 preparation method Methods 0.000 title claims abstract description 16
- 239000002002 slurry Substances 0.000 claims abstract description 87
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 60
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 60
- 239000010703 silicon Substances 0.000 claims abstract description 60
- 238000003756 stirring Methods 0.000 claims abstract description 54
- 239000011230 binding agent Substances 0.000 claims abstract description 32
- 238000002156 mixing Methods 0.000 claims abstract description 30
- 239000002562 thickening agent Substances 0.000 claims abstract description 30
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 30
- 239000002270 dispersing agent Substances 0.000 claims abstract description 27
- 239000006258 conductive agent Substances 0.000 claims abstract description 26
- 239000002243 precursor Substances 0.000 claims abstract description 25
- 239000010405 anode material Substances 0.000 claims abstract description 16
- 238000004519 manufacturing process Methods 0.000 claims abstract description 14
- 239000000853 adhesive Substances 0.000 claims abstract description 7
- 230000001070 adhesive effect Effects 0.000 claims abstract description 7
- 239000001768 carboxy methyl cellulose Substances 0.000 claims description 33
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 26
- 229920002134 Carboxymethyl cellulose Polymers 0.000 claims description 22
- 235000010948 carboxy methyl cellulose Nutrition 0.000 claims description 22
- 239000008112 carboxymethyl-cellulose Substances 0.000 claims description 22
- IXPNQXFRVYWDDI-UHFFFAOYSA-N 1-methyl-2,4-dioxo-1,3-diazinane-5-carboximidamide Chemical compound CN1CC(C(N)=N)C(=O)NC1=O IXPNQXFRVYWDDI-UHFFFAOYSA-N 0.000 claims description 21
- 239000000661 sodium alginate Substances 0.000 claims description 21
- 235000010413 sodium alginate Nutrition 0.000 claims description 21
- 229940005550 sodium alginate Drugs 0.000 claims description 21
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 claims description 16
- 229910001416 lithium ion Inorganic materials 0.000 claims description 16
- 239000007773 negative electrode material Substances 0.000 claims description 14
- 229920002125 Sokalan® Polymers 0.000 claims description 11
- DPXJVFZANSGRMM-UHFFFAOYSA-N acetic acid;2,3,4,5,6-pentahydroxyhexanal;sodium Chemical compound [Na].CC(O)=O.OCC(O)C(O)C(O)C(O)C=O DPXJVFZANSGRMM-UHFFFAOYSA-N 0.000 claims description 11
- 235000019812 sodium carboxymethyl cellulose Nutrition 0.000 claims description 11
- 229920001027 sodium carboxymethylcellulose Polymers 0.000 claims description 11
- 229910021389 graphene Inorganic materials 0.000 claims description 10
- 239000002048 multi walled nanotube Substances 0.000 claims description 10
- 229910052814 silicon oxide Inorganic materials 0.000 claims description 10
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 9
- 239000002109 single walled nanotube Substances 0.000 claims description 8
- 229920003048 styrene butadiene rubber Polymers 0.000 claims description 7
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 4
- 239000006257 cathode slurry Substances 0.000 claims description 3
- 239000003792 electrolyte Substances 0.000 claims description 3
- 239000007787 solid Substances 0.000 abstract description 31
- 230000000694 effects Effects 0.000 abstract description 10
- 230000008719 thickening Effects 0.000 abstract description 8
- 239000002131 composite material Substances 0.000 abstract description 5
- 239000002245 particle Substances 0.000 abstract description 4
- 230000003247 decreasing effect Effects 0.000 abstract description 3
- 230000000630 rising effect Effects 0.000 abstract description 3
- 238000000576 coating method Methods 0.000 description 31
- 239000011248 coating agent Substances 0.000 description 30
- 238000000034 method Methods 0.000 description 22
- 239000000463 material Substances 0.000 description 17
- 230000000052 comparative effect Effects 0.000 description 13
- 229910002804 graphite Inorganic materials 0.000 description 10
- 239000010439 graphite Substances 0.000 description 10
- 238000005303 weighing Methods 0.000 description 8
- 239000000843 powder Substances 0.000 description 7
- 230000008569 process Effects 0.000 description 7
- 239000003575 carbonaceous material Substances 0.000 description 6
- 238000012546 transfer Methods 0.000 description 6
- 239000005543 nano-size silicon particle Substances 0.000 description 4
- 239000002120 nanofilm Substances 0.000 description 4
- 238000004537 pulping Methods 0.000 description 4
- 230000009467 reduction Effects 0.000 description 4
- 239000002210 silicon-based material Substances 0.000 description 4
- 239000002174 Styrene-butadiene Substances 0.000 description 3
- HMDDXIMCDZRSNE-UHFFFAOYSA-N [C].[Si] Chemical compound [C].[Si] HMDDXIMCDZRSNE-UHFFFAOYSA-N 0.000 description 3
- 239000006256 anode slurry Substances 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 238000001514 detection method Methods 0.000 description 3
- 238000002474 experimental method Methods 0.000 description 3
- 239000002070 nanowire Substances 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 239000011889 copper foil Substances 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 239000011888 foil Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000002105 nanoparticle Substances 0.000 description 2
- 239000002071 nanotube Substances 0.000 description 2
- 238000004062 sedimentation Methods 0.000 description 2
- 239000002620 silicon nanotube Substances 0.000 description 2
- 229910021430 silicon nanotube Inorganic materials 0.000 description 2
- 238000004513 sizing Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- SICLLPHPVFCNTJ-UHFFFAOYSA-N 1,1,1',1'-tetramethyl-3,3'-spirobi[2h-indene]-5,5'-diol Chemical compound C12=CC(O)=CC=C2C(C)(C)CC11C2=CC(O)=CC=C2C(C)(C)C1 SICLLPHPVFCNTJ-UHFFFAOYSA-N 0.000 description 1
- QMGYPNKICQJHLN-UHFFFAOYSA-M Carboxymethylcellulose cellulose carboxymethyl ether Chemical compound [Na+].CC([O-])=O.OCC(O)C(O)C(O)C(O)C=O QMGYPNKICQJHLN-UHFFFAOYSA-M 0.000 description 1
- 239000002000 Electrolyte additive Substances 0.000 description 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 238000000498 ball milling Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000006255 coating slurry Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000004584 polyacrylic acid Substances 0.000 description 1
- 239000007774 positive electrode material Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical class [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 1
- 238000007581 slurry coating method Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 239000012257 stirred material Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 230000002522 swelling effect Effects 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Landscapes
- Battery Electrode And Active Subsutance (AREA)
Abstract
In order to overcome various technical problems encountered in the production of the existing high-specific-capacity silicon negative electrode plate, the application provides a preparation method of negative electrode slurry, a negative electrode plate and a battery; stirring and mixing the conductive agent, the adhesive a and water according to mass fraction to prepare a thickening agent; stirring and mixing the binder b and water according to mass fraction to prepare a dispersing agent; adding a silicon anode material into the prepared dispersing agent to prepare a precursor; adding the prepared thickener into a precursor, uniformly mixing, and carrying out vacuum defoaming to obtain negative electrode slurry; the application uses a composite conductive agent and binder system, improves the total specific surface area of all particles in the slurry by adding various conductive agents with higher specific surface areas, and is matched with the binder system with better thickening effect, thereby reducing the solid content and simultaneously keeping the viscosity of the slurry from decreasing and rising reversely, and simultaneously using a special mixing sequence, thereby ensuring the advantage that the slurry can be uniformly mixed in a shorter time under a high viscosity state.
Description
Technical Field
The application belongs to the technical field of production and manufacturing of lithium ion batteries, and particularly relates to a negative electrode slurry, a negative electrode plate and a preparation method of a battery.
Background
At present, graphite is mainly used as a negative electrode material of the lithium ion battery, however, the actual performance (specific capacity is up to about 365 mAh/g) of the graphite negative electrode is close to the theoretical performance (specific capacity is 372 mAh/g) of the graphite negative electrode at present, and the conventional lithium ion battery cannot be obviously improved in capacity after the graphite negative electrode is continuously developed, so that a new negative electrode material needs to be developed for continuously improving the capacity of the lithium ion battery. Among the now more feasible anode materials of the next generation lithium ion battery, the silicon anode material (comprising pure Si, the theoretical capacity of 4200mAh/g and SiOx, the theoretical capacity of 2500mAh/g, various SiC materials, and the theoretical capacity depending on the process) has the largest application prospect.
In the former process of lithium ion battery manufacturing, pulping and coating are the most important two major processes. The pulping means that materials such as positive and negative electrode main materials, conductive agents, binders and the like of the lithium ion battery are uniformly dispersed in water or a certain organic solvent (mainly NMP) by stirring, centrifuging, ball milling and the like. Coating refers to a process of uniformly coating slurry obtained in pulping on a current collector (typically copper foil and aluminum foil) of a lithium ion battery by using a transfer, spray coating or other methods. The coating is as uniform as possible during coating, otherwise, the safety problems such as lithium precipitation and the like of the subsequent battery can be caused, the slurry is required to be fully and uniformly mixed during pulping, and the physicochemical properties (mainly the viscosity and fineness) of the coating result are required to be as stable as possible due to the slurry.
Because the specific capacity of the silicon negative electrode is generally 7-13 times that of the graphite negative electrode, the density of the silicon negative electrode and the graphite negative electrode is not great (graphite is in 2.1g/cm 3 About, the silicon content is 2.33g/cm 3 ) When preparing the negative electrode sheet with the same surface capacity, the sheet coating surface density of the silicon negative electrode material is only 1/7-1/13 of that of the graphite negative electrode, and the physicochemical properties of the slurry with normal surface capacities are generally similar (the viscosity is 5000mpa x s-800 mpa x s, the solid content is 45% -60% and the fineness is about 60 um), while the conventional lithium ion battery coating equipment is mostly designed according to the characteristics and the coating amount of the graphite negative electrode slurry, when preparing the graphite negative electrode sheet by using the coating equipment, the blade height of a transfer coater is generally about 300um, and when coating the silicon negative electrode sheet with the same surface capacity by using the equipment, the blade height needs to be reduced to 1/7-1/13 before, at the moment, the blade height of the coater is even smaller than the fineness (60 um) of the slurry, so that larger particles in the slurry can not be coated on the coater, and even if the blade edge can be coated, the problem that the fluctuation of the coating surface density is large and the blade edge is far away from the design tolerance can occur. In order to solve this problem, it is necessary to reduce the solid content of the slurry so that a lower areal density can be applied at the same coater blade height, but the viscosity of the slurry is reduced as the solid content is reduced, and the stability of the slurry is deteriorated after the viscosity is reduced, which is disadvantageous for a short period of storage. Meanwhile, after the viscosity is reduced, the fluidity of the slurry can be obviously improved, and the transfer coating can have serious watermarking problems, so that the die cutting and welding of the subsequent pole pieces are affected. Therefore, how to overcome the above-mentioned technical problems and drawbacks becomes an important problem to be solved.
Disclosure of Invention
Aiming at various technical problems encountered in the production of the existing high-specific-capacity silicon negative electrode plate, the application provides a preparation method of negative electrode slurry, a negative electrode plate and a battery.
The technical scheme adopted by the application for solving the technical problems is as follows:
the application provides a preparation method of negative electrode slurry, which comprises the following steps:
mixing 2-5wt% of conductive agent, 1.5wt% to 4wt% of binder a and 91-96.5wt% of water by using a stirring mixer to prepare a thickener;
mixing 2-6wt% of the adhesive b and 94-98wt% of water by using a stirring mixer to prepare a dispersing agent;
adding a silicon anode material into the prepared dispersing agent, and uniformly mixing by using a stirring mixer to prepare a precursor, wherein the mass ratio of the dispersing agent to the silicon anode material is 1:1 to 9;
and adding the prepared thickener into the precursor in batches, uniformly mixing by using a stirring mixer after each addition, and finally obtaining the cathode slurry after vacuum defoaming.
Optionally, the conductive agent is one or more selected from conductive carbon black (SP), graphene, multi-walled carbon nanotubes (MWCNT), and single-walled carbon nanotubes (SWCNT).
Optionally, the binder a includes one or more of Sodium Alginate (SA), sodium carboxymethylcellulose (CMC), styrene-butadiene rubber (SBR), and polyacrylic acid (PAA).
Optionally, the binder b includes one or more of Sodium Alginate (SA), sodium carboxymethylcellulose (CMC), and polyacrylic acid (PAA).
Optionally, the silicon negative electrode material includes one or more of Si, siC, and SiOx.
Optionally, when the silicon negative electrode slurry is prepared, the thickener is added into the precursor in batches of 2-5 parts, and the mass ratio of the precursor to the thickener in the negative electrode slurry is 1:1 to 3.
Optionally, the stirring mixer uses a planetary stirrer to mix the slurry, the revolution speed is 20-50r/min, the rotation speed is 2000-4000r/min, and the stirring time is 2-6 hours.
Optionally, the stirring mixer uses a planetary stirrer to carry out vacuum defoaming, the revolution speed is 20-50r/min, the rotation speed is 2000-4000r/min, the vacuum degree is-95 to-98 KPa, and the defoaming time is 6-10 hours.
In another aspect, a silicon negative electrode sheet is provided, comprising a current collector and a negative electrode body, wherein the negative electrode body is prepared from the silicon negative electrode slurry described in any one of the above.
In still another aspect, a lithium ion battery is provided, including a positive plate, a negative plate, and an electrolyte, where the negative plate is the silicon negative plate.
According to the preparation method of the negative electrode slurry, the total specific surface area of all particles in the slurry is increased by adding various conductive agents with higher specific surface areas through using a composite conductive agent and binder system, and the binder system with better thickening effect is matched, so that the viscosity of the slurry is kept from decreasing and rising reversely while the solid content is reduced, and meanwhile, a special mixing sequence is used, so that the slurry can be uniformly mixed in a short time under a high viscosity state; meanwhile, the slurry can solve the problem of insufficient precision of a coater when the high-specific-capacity silicon anode is coated, and can also solve the problem of serious watermarking phenomenon during coating caused by viscosity reduction of the slurry due to solid content reduction, and meanwhile, the stability of the slurry is obviously improved.
Drawings
FIG. 1 is a graph showing the effect of a conventional slurry coating;
FIG. 2 is a graph showing the effect of the slurry of the present application when applied;
FIG. 3 is a comparative graph of slurry stability according to the present application;
reference numerals in the drawings of the specification are as follows:
1-layer; 2-foil; 3-watermarking.
Detailed Description
In order to make the technical problems, technical schemes and beneficial effects solved by the application more clear, the application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.
The test methods used in the following examples are conventional methods unless otherwise specified; the materials, reagents and the like used, unless otherwise specified, are those commercially available.
The embodiment of the application provides a preparation method of negative electrode slurry, which comprises the following steps:
(1) Mixing 2-5wt% of conductive agent, 1.5wt% to 4wt% of binder a and 91-96.5wt% of water by using a stirring mixer to prepare a thickener;
specifically, the conductive agent is a conductive agent with high specific surface area, and the conductive agent with high specific surface area is weighed by weight percent to be 2-4wt%, the conductive agent with high specific surface area comprises one or more of conductive carbon black (SP), multi-wall carbon nano tube (MWCNT) and single-wall carbon nano tube (SWCNT), the conductive carbon black (SP), single-wall carbon nano tube (SWCNT), multi-wall carbon nano tube (MWCNT) and the like have larger specific surface area, and the addition of the conductive agent can increase the surface energy, so that the viscosity of the slurry is improved, but the dispersion of the slurry is unfavorable.
Therefore, 0.5-3 wt% of graphene is also required to be weighed according to the mass fraction, and the addition of the graphene can play a role in lubrication, so that the slurry is easier to disperse.
In some embodiments, the ratio of the high specific surface area conductive agent to the added amount of graphene is 1-3:1.
in a preferred embodiment, the addition amount of the graphene is 0.5%, 1%, 1.5%, 2%.
In a preferred embodiment, the high specific surface area conductive agent is added in an amount of 2%, 2.5%, 3%, 3.5%, 4%.
Specifically, 1.5wt% -4wt% of a binder a is weighed according to mass fraction, wherein the binder a comprises one or more of polyacrylic acid (PAA), sodium Alginate (SA), sodium carboxymethylcellulose (CMC) and Styrene Butadiene Rubber (SBR); the viscosity of the slurry can be improved by adding polyacrylic acid (PAA), sodium Alginate (SA), sodium carboxymethylcellulose (CMC) and Styrene Butadiene Rubber (SBR).
And adding the weighed high-specific-surface-area conductive agent, graphene and binder into water with the weight ratio of 91-96.5%. Using a planetary stirrer, wherein the revolution speed is 20-50r/min, the rotation speed is 2000-5000r/min, and the stirring time is 3-6 hours; and stirring for 4-6 hours at revolution speed of 20-50r/min, rotation speed of 2000-4000r/min and vacuum degree of-90 MPa to-98 MPa to prepare the mixed thickener with viscosity of 12000-20000 MPa.
The mixed thickener prepared by the application contains a plurality of conductive agents and binders, so that the mixed thickener has high viscosity and good stability, can be stored for 15-20 days after being prepared, and is time-consuming to prepare, so that the preparation is independent from other steps, and the mixed thickener is prepared once per half month in actual production, is directly taken when being used, and can reduce the total mixing time.
Specifically, the planetary mixer is adopted for the stirring mixer, and the planetary mixer balances the power of the mixer to each device, so that the mechanical acting force of the planetary mixer can be well realized, and the stirred materials are higher in homogeneity and shorter in time than those stirred by the traditional mixing equipment.
Preferably, the revolution speed of the planetary mixer is 20r/min, 25r/min, 30r/min, 35r/min, 40r/min, 45r/min and 50r/min;
the rotation speed of the planetary stirrer is 2000r/min, 2500r/min, 3000r/min, 3500r/min, 4000r/min, 4500r/min and 5000r/min;
the stirring time of the planetary stirrer is 3h, 3.5h, 4h, 4.5h, 5h, 5.5h and 6h;
the vacuum degree of the planetary mixer is-90 MPa, -91MPa, -92MPa, -93MPa, -94MPa, -95MPa, -96MPa, -97MPa and-98 MPa;
the stirring time of the planetary stirrer under the vacuum degree is 4h, 4.5h, 5h, 5.5h and 6h;
along with the increase of the mass of the mixed thickening agent, the revolution speed and the rotation speed of the planetary mixer are reduced, the stirring time length and the stirring time length under the vacuum degree are increased, the vacuum degree is determined according to the revolution speed, the rotation speed, the stirring time length and the stirring under the vacuum degree, the specific situation is adjusted according to the actual situation, the requirements are not more made, and the purpose of the application can be achieved.
The application improves the total specific surface area of all particles in the slurry by adding various conductive agents with higher specific surface areas through using a composite conductive agent and adhesive system, and is matched with the adhesive system with better thickening effect, thereby reducing the solid content and simultaneously keeping the viscosity of the slurry from decreasing and rising reversely, and simultaneously ensuring that the slurry can be uniformly mixed in a shorter time under a high-viscosity state by using a special mixing sequence.
(2) Mixing 2-6wt% of the adhesive b and 94-98wt% of water by using a stirring mixer to prepare a dispersing agent;
specifically, weighing 2-6wt% of binder b according to mass fraction, wherein the binder b comprises one or more of polyacrylic acid (PAA), sodium Alginate (SA) and sodium carboxymethylcellulose (CMC); polyacrylic acid (PAA), sodium Alginate (SA) and sodium carboxymethylcellulose (CMC) are all binders commonly used for lithium ion batteries, and the viscosity of the slurry can be improved by adding the binders;
the weighed adhesive b is added into water with the proportion of 94-98 wt%. Using a planetary stirrer, stirring for 2-3 hours at the revolution speed of 20-50r/min, the rotation speed of 2000-5000r/min and the vacuum degree of-90 MPa to-98 MPa, and preparing the dispersing agent.
The binder is used for preparing the dispersing agent because the thickening effect of the binder is good, so that the viscosity of the dispersing agent is improved, and the stability of the slurry is improved.
In addition, since the powder of CMC and the silicon negative electrode material are directly added into water, and the two powders are mixed in water at the same time and are easy to agglomerate, CMC is required to be dispersed in water to prepare a dispersing agent, and then the silicon negative electrode material is added into the dispersing agent to prepare a precursor.
In some embodiments, the binder b is preferably sodium carboxymethyl cellulose (CMC) and a combination of sodium carboxymethyl cellulose (CMC) and polyacrylic acid (PAA) or Sodium Alginate (SA).
In a preferred embodiment, the sodium carboxymethyl cellulose (CMC) is added in an amount of 1%, 2%, 3%, 4%, 5%, 6%.
In a preferred embodiment, the polyacrylic acid (PAA) is added in an amount of 1%, 2%.
In a preferred embodiment, the Sodium Alginate (SA) is added in an amount of 1%, 2%.
(3) Adding a silicon anode material into the prepared dispersing agent, uniformly mixing by using a stirring mixer, wherein the stirring mixer adopts a planetary stirrer, the revolution speed is 20-50r/min, the rotation speed is 2000-5000r/min, and stirring for 2-3 hours under the vacuum degree of-90 MPa to-98 MPa to prepare a precursor; wherein, the mass ratio of the dispersing agent to the silicon anode material is 1:1 to 9;
specifically, the silicon negative electrode material includes one or more of Si, siC, and SiOx.
The silicon anode material can be a conventional silicon anode material, and further, the silicon anode material can comprise one or more of silicon nano particles, silicon nano wires, silicon nano tubes, silicon nano films, silicon oxides, pre-lithiated silicon oxide powder and silicon carbon materials.
In particular to the application, the silicon anode material comprises one or more of Si nano particles, si nano wires, si nano tubes, si nano films, oxidized Si, pre-lithiated Si oxygen powder and Si carbon materials; one or more of SiC nano particles, siC nano wires, siC nano tubes, siC nano films, sub-SiC oxides, pre-lithiated SiC oxygen powder and SiC carbon materials; one or more of SiOx nanoparticles, siOx nanowires, siOx nanotubes, siOx nanofilm, oxysiox, prelithiated SiOx oxygen powder, siOx carbon material.
In the present application, the silicon carbon material is a negative electrode silicon carbon material common in the art.
Although the silicon negative electrode material is hydrophilic, the viscosity of the silicon negative electrode material is low by dispersing it in pure water, and sedimentation starts after standing for about 10 minutes, so that it is necessary to add CMC as a binder having a good thickening ability as a dispersing agent to prepare a precursor having a high stability.
Preferably, the mass ratio of the silicon anode material to the dispersant prepared in the second step is 1:3, a step of;
preferably, the mass ratio of the silicon anode material to the dispersant prepared in the second step is 1:4, a step of;
preferably, the mass ratio of the silicon anode material to the dispersant prepared in the second step is 1:5, a step of;
further, in order to increase the energy density as much as possible and control the volume expansion of silicon, the mass ratio of the silicon material to the conductive agent is preferably 40 to 50:20 to 30. In addition, in order to enhance the cooperation of the silicon material and the composite binder, the bonding effect of the composite binder on the silicon material and the alleviation of the swelling effect of the silicon material are enhanced as much as possible.
(4) And adding the prepared thickener into the precursor in batches, uniformly mixing by using a stirring mixer after each addition, and finally obtaining the cathode slurry after vacuum defoaming.
Specifically, a thickener with the total mass being 1-3 times of that of a precursor is added into the precursor for 2-5 times, a planetary stirrer is used after each addition, the revolution speed is 20-50r/min, the rotation speed is 2000-5000r/min, the mixture is stirred for 2-3 hours under the vacuum degree of minus 90MPa to minus 98MPa, and finally the silicon negative electrode slurry with the solid content of 8% -25% and the viscosity of 10000-18000 mPa is prepared.
When mixing, a 15-liter planetary mixer is used, the maximum revolution speed of the machine is 60r/min, the maximum rotation speed is 6000r/min, through experiments, under the condition of lower solid content (solid content is 10%), the revolution is 20r/min, the rotation is 2000r/min, the mixed thickener is added in two times, the fineness of the final slurry can be reduced to below 60um after stirring for 2 hours (namely, the processing is completed, the material can be discharged), under the condition of higher solid content (solid content is 25%), the revolution is 50r/min, the rotation is 5000r/min, the mixed thickener is added in two times, and the fineness of the final slurry can be reduced to below 60um after stirring for 3 hours. The stirring under the vacuum environment is to prevent bubbles from being mixed in the slurry with high concentration in the stirring process (the maximum vacuum degree which can be pumped by a machine is-98 MPa, and the vacuum degree is controlled to be not lower than-90 MPa due to the air tightness problem and gradual decrease of the vaporization vacuum degree of water in the stirring process).
Since the viscosity of the precursor is usually 3000mPa s-4000mPa s, which is far smaller than that of the mixed thickener, if all the mixed thickener is added to the precursor at one time and stirred, the slurry is difficult to mix uniformly, and a large amount of stirring time is consumed, so that the mixed thickener is added in batches, the stirring time can be reduced, and the state of the slurry can be confirmed for many times.
In the prior art, all raw materials are directly added into a mixer during mixing, and the final slurry is obtained through one-time stirring, but the method has some problems, so the special mixing sequence adopted in the application is as follows:
first, although the silicon negative electrode material is hydrophilic, the viscosity of the silicon negative electrode material is low by dispersing it in pure water, and sedimentation starts after standing for about 10 minutes, so that it is necessary to add CMC as a dispersant, which is a binder having a high thickening ability, to prepare a precursor having high stability.
Secondly, because CMC powder and silicon negative electrode material are directly added into water, the two powders are mixed in water at the same time and are easy to agglomerate, CMC is required to be dispersed in water to prepare a dispersing agent, and then the silicon negative electrode material is added into the dispersing agent to prepare a precursor.
The mixed thickener containing various conductive agents and binders has high viscosity and good stability, can be stored for 15-20 days after being prepared, and is time-consuming to prepare, so that the preparation is independent from other steps, and the mixed thickener is prepared once every half month in actual production, is directly taken when in use, and can reduce the total mixing time.
Finally, since the viscosity of the precursor is usually 3000mPa s to 4000mPa s, which is far less than that of the mixed thickener, if all the mixed thickener is added to the precursor at one time and stirred, the slurry is difficult to mix uniformly, and a large amount of stirring time is consumed, so that the mixed thickener is added in batches, the stirring time can be reduced, and the state of the slurry can be confirmed for many times.
In summary, the method provided by the application can be used for preparing the low-solid-content high-viscosity silicon anode slurry, and compared with the low-solid-content normal-viscosity slurry prepared by the method, the method has the following advantages:
firstly, the viscosity of the slurry is improved, the stability of the slurry is improved, the slurry manufactured by the method can be kept stand and stored for more than 2 days without deterioration, the fluidity is relatively reduced, and the watermarking problem encountered during coating is thoroughly solved.
Then, the solid content of the slurry is reduced, and a thinner pole piece can be coated with the same blade height of the coater at the time of transfer coating, and at this time, the coating tolerance of the coater is reduced.
In another embodiment, the application provides a silicon negative electrode plate, which comprises a current collector and a negative electrode main body, wherein the negative electrode main body is prepared from the silicon negative electrode slurry.
And coating the prepared silicon negative electrode slurry on one side surface of the copper foil to obtain the silicon negative electrode plate.
In a third embodiment, the application provides a lithium ion battery, which comprises a positive plate, a negative plate and electrolyte, wherein the negative plate is the silicon negative plate.
The application is further illustrated by the following examples.
Table 1 examples 1-16 design of thickening mixtures;
table 2 design of dispersants, host materials and final slurries for examples 1-16;
example 1
The preparation method of the negative electrode slurry and the battery thereof are described in the embodiment, and the preparation method comprises the following operation steps:
the SP and the MWCNT are selected as high specific surface area conductive agents, PAA, SA, CMC is used as a thickening binder, and the mass ratio of the SP to the MWCNT to water is 2:0.5:2:0.5:1:94, mixing, using a planetary mixer, revolution speed is 40r/min, rotation speed is 3500r/min, stirring for 4 hours under vacuum degree of-95 MPa, and preparing the mixed thickener with viscosity of 16000 mPa.
CMC is selected as a dispersing agent, and the mass ratio of CMC to water is 3:97, mixing, stirring for 4 hours under the vacuum degree of-95 MPa by using a planetary stirrer, wherein the revolution speed is 40r/min and the rotation speed is 3500r/min, and preparing the dispersing agent.
Using a nano silicon material as a cathode main material, and mixing the nano silicon material with a dispersing agent according to the mass ratio of 1:5, mixing the materials by a planetary mixer, wherein the revolution speed is 40r/min, the rotation speed is 3500r/min, and stirring the materials for 4 hours under the vacuum degree of-95 MPa to prepare the precursor.
Finally, the mass ratio of the precursor is 1:1, adding the mixed thickener into the precursor for 3 times, wherein a planetary stirrer is used after each addition, the revolution speed is 30r/min, the rotation speed is 4000r/min, and stirring is carried out for 2 hours under the vacuum degree of-95 MPa, so that the finished slurry is finally obtained, the solid content of the slurry is about 13.2%, and the viscosity is 13500 mPa.
Examples 2 to 16
Examples 2 to 16 are for explaining the preparation method of the negative electrode slurry and the battery thereof disclosed in the present application, including most of the operation steps in example 1, which are different in that:
the electrolyte additive components and the positive electrode material layers shown in tables 1-2 were used.
Comparative example 1 (conventional low solids, normal viscosity silicon negative electrode slurry):
graphene and SP are used as conductive agents, CMC and SBR are used as binders, siOx material with the capacity of 1400mAh/g is used as a main material, and water is used as a solvent.
Water, CMC, SBR, graphene, SP and SiOx were mixed according to 88:2:1:0.5:0.5:8, adding water and CMC, stirring for the first time, adding graphene, SP and SiOx, stirring for the second time, adding SBR, stirring for the third time, sequentially mixing materials, wherein a planetary mixer is used for each stirring, the first revolution speed is 30r/min, the rotation speed is 2000r/min, stirring is carried out for 2 hours under the vacuum degree of-95 MPa, the second revolution speed is 40r/min, the rotation speed is 4000r/min, stirring is carried out for 3 hours under the vacuum degree of-95 MPa, the third revolution speed is 40r/min, the rotation speed is 4000r/min, and stirring is carried out for 2 hours under the vacuum degree of-95 MPa.
Finally, the slurry with viscosity of 4000 mPas and solid content of 11% is obtained, the stability of the slurry is poor (shown in the third picture), the viscosity of the slurry is reduced by 25% after standing for about 5 hours, the upper layer of the slurry is separated out by water, the slurry is coated, the serious watermarking problem shown in the first picture also appears, and the coating surface density is 4.0mg/cm 2 When the concentration is within + -0.5 mg/cm 2 Is a tolerance to a tolerance of (c).
Performance testing
(1) The viscosities and solids contents of the slurries prepared in examples 1-16 were measured and the results are shown in Table 3 below; wherein the solid content is the solid content when the detection slurry is discharged.
The viscosity detection method comprises the following steps: and (3) starting timing from the discharge of the slurry, detecting the viscosity change of the slurry at 0h, 1h, 2h, 4h, 12h and 24h by adopting a rotary viscosity tester (DV 2T type rotary viscosity tester, no. 64 rotor), and finally taking an average value.
The solid content measuring method comprises the following steps: and (3) taking 16 clean culture dishes after the slurry is discharged, drying the dishes in a constant temperature oven at 105+/-2 ℃ for 30 minutes, taking out the dishes, putting the dishes into a dryer, cooling the dishes to room temperature, and weighing the dishes to obtain the weight W of the culture dishes. In two dishes of known constant weight, 1-2G of the sample (slurry) was weighed into each dish, to the nearest 0.001G, to obtain the exact weight G of the sample.
After the mass of the sample is weighed, uniformly distributing the sample at the bottom of a culture dish, baking the sample in a constant-temperature oven at 160 ℃ for 30min, taking out the sample, putting the sample into a dryer, cooling the sample to room temperature, and weighing the sample; the drying and weighing steps (baking in a constant temperature oven at 160 ℃ for 30min, taking out and putting into a dryer to cool to room temperature, and weighing) are repeated until the weight difference between the front and rear weighing is not more than 0.01 g (the total weighing is accurate to 0.01 g), and the last weighing result is the weight W1 of the baked sample and the container. Two samples were assayed in parallel.
Calculation method
The solids content% (X) is calculated as follows:
X＝(W1-W)/G×100
in the formula:
x is the solid content of the slurry in units;
w-weight of container, unit: g;
w1-weight of sample and container after baking, unit: g;
g-weight of sample, unit: gram (g).
The experimental results are taken as the average value of two parallel experiments, and the relative error of the two average experiments is not more than 3 percent.
The results are shown in Table 3
TABLE 3 final slurries viscosity and solids content of examples 1-16
| Numbering device | Final slurry viscosity/mpa.s | Solid content |
| Example 1 | 13500 | 13.230％ |
| Example 2 | 10000 | 8.000％ |
| Example 3 | 18000 | 24.920％ |
| Example 4 | 15000 | 16.120％ |
| Example 5 | 11000 | 14.425％ |
| Example 6 | 12000 | 14.450％ |
| Example 7 | 16000 | 24.000％ |
| Example 8 | 15000 | 18.450％ |
| Example 9 | 13000 | 13.230％ |
| Example 10 | 11000 | 15.300％ |
| Example 11 | 15000 | 18.800％ |
| Example 12 | 15000 | 20.050％ |
| Example 13 | 14000 | 12.240％ |
| Example 14 | 17000 | 14.800％ |
| Example 15 | 13000 | 15.300％ |
| Example 16 | 14500 | 12.000％ |
| Comparative example 1 | 4000 | 11.000％ |
As shown in Table 3, the viscosity of examples 1-16 using the preparation method of the negative electrode slurry of the present application was in the range of 10000-18000/mpa.s, the solid content was 8% -25%, the viscosity of comparative example 1 was 4000/mpa.s, the viscosity of the present application was far greater than that of comparative example 1, and at the same time, the solid content of the prior art was 40% -50% compared with the prior art, therefore, compared with comparative example 1 and the prior art, the solid content of the present application was reduced to 8% -25%, while maintaining the viscosity thereof in the range of 10000-18000 mpa.s, the problem of coating process due to the viscosity change of the slurry could be completely avoided, and the ultra-thin high specific capacity silicon negative electrode sheet was prepared.
In addition, the contents of the silicon negative electrode main material and the binder in the negative electrode slurry are not changed, but the peel strength of a pole piece prepared from the slurry prepared by the method is greatly improved; the method can improve various technical problems caused by insufficient precision of a coater or too low viscosity of the slurry when the silicon negative electrode slurry with low solid content is coated.
Coatability test
The corresponding finished sizing agents are respectively prepared according to the corresponding method of the comparative example 1 and the example 16, the sizing agents of the comparative example 1 and the example 16 are respectively coated on a current collector of a lithium ion battery, and the coating effect is observed;
the coating effect of comparative example 1 as shown in fig. 1, the current collector of the lithium ion battery coated with the slurry of comparative example 1 presents serious watermarking problems;
the coating effect of example 16 as shown in fig. two, the current collector of the lithium ion battery coated with the slurry of example 16 did not show any watermark problem at all;
the method provided by the application can obtain the high specific capacity silicon negative electrode slurry with lower solid content and higher viscosity, and the problem of insufficient precision of a coating machine when the high specific capacity silicon negative electrode is coated can be solved by using the slurry, and the serious watermarking phenomenon during coating caused by the viscosity reduction of the slurry due to the solid content reduction can be solved, and meanwhile, the stability of the slurry is obviously improved.
(2) Stability detection
The slurries of comparative example 1 and example 16 were left to stand at normal temperature for 24 hours, and the stability of the slurries was monitored, respectively, to prepare the corresponding finished slurries according to the corresponding methods described above.
As shown in the third graph, the viscosity of the slurry of comparative example 1 was reduced by 25% after the slurry was left to stand for about 5 hours, water was separated from the upper layer of the slurry, the slurry was coated with the water, the water was severely marked as in the first graph, and the coating surface density was 4.0mg/cm 2 When the concentration is within + -0.5 mg/cm 2 The slurry of comparative example 1 had poor stability.
The slurry of example 16 was viscosity based after 48 hours of restThe coating material was not changed, water was not deposited on the surface of the slurry, and the surface density of the coating material was 4.0mg/cm by transfer coating using the same 2 At the time, only + -0.1 mg/cm 2 And therefore the stability of the slurry of the present application is high.
In summary, the low-solid-content and high-viscosity silicon anode slurry prepared by the method provided by the application has the following advantages compared with the low-solid-content and normal-viscosity slurry prepared by the method without the application:
firstly, the viscosity of the slurry is improved, the stability of the slurry is improved, the slurry manufactured by the method can be kept stand and stored for more than 2 days without deterioration, the fluidity is relatively reduced, and the watermarking problem encountered during coating is thoroughly solved.
Then, the solid content of the slurry is reduced, and a thinner pole piece can be coated with the same blade height of the coater at the time of transfer coating, and at this time, the coating tolerance of the coater is reduced.
Finally, as a main object of the present application, the low-solid-content and high-viscosity slurry can improve various process problems caused by insufficient precision of a coater or too low viscosity of the slurry, which are encountered when the low-solid-content silicon anode slurry is coated.
The foregoing description of the preferred embodiments of the application is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the application.
Claims (10)
1. A preparation method of negative electrode slurry is characterized by comprising the following steps: the preparation method comprises the following steps:
mixing 2-5wt% of conductive agent, 1.5wt% to 4wt% of binder a and 91-96.5wt% of water by using a stirring mixer to prepare a thickener;
mixing 2-6wt% of the adhesive b and 94-98wt% of water by using a stirring mixer to prepare a dispersing agent;
adding a silicon anode material into the prepared dispersing agent, and uniformly mixing by using a stirring mixer to prepare a precursor, wherein the mass ratio of the dispersing agent to the silicon anode material is 1:1 to 9;
and adding the prepared thickener into the precursor in batches, uniformly mixing by using a stirring mixer after each addition, and finally obtaining the cathode slurry after vacuum defoaming.
2. The method for producing a negative electrode slurry according to claim 1, characterized in that: the conductive agent is one or more of conductive carbon black (SP), graphene, multi-wall carbon nanotubes (MWCNT) and single-wall carbon nanotubes (SWCNT).
3. The method for producing a negative electrode slurry according to claim 1, characterized in that: the binder a comprises one or more of Sodium Alginate (SA), sodium carboxymethylcellulose (CMC), styrene Butadiene Rubber (SBR) and polyacrylic acid (PAA).
4. The method for producing a negative electrode slurry according to claim 1, characterized in that: the binder b includes one or more of Sodium Alginate (SA), sodium carboxymethylcellulose (CMC), and polyacrylic acid (PAA).
5. The method for producing a negative electrode slurry according to claim 1, characterized in that: the silicon negative electrode material includes one or more of Si, siC, and SiOx.
6. The method for producing a negative electrode slurry according to claim 1, characterized in that: when the silicon negative electrode slurry is prepared, the thickener is uniformly divided into 2-5 parts and added into the precursor in batches, and the mass ratio of the precursor to the thickener in the negative electrode slurry is 1:1 to 3.
7. The method for producing a negative electrode slurry according to claim 1, characterized in that: the stirring mixer is used for mixing slurry by using a planetary stirrer, the revolution speed is 20-50r/min, the rotation speed is 2000-4000r/min, and the stirring time is 2-6 hours.
8. The method for producing a negative electrode slurry according to claim 1, characterized in that: the stirring mixer uses a planetary stirrer to carry out vacuum defoaming, the revolution speed is 20-50r/min, the rotation speed is 2000-4000r/min, the vacuum degree is-95 to-98 KPa, and the defoaming time is 6-10 hours.
9. A silicon negative electrode sheet comprising a current collector and a negative electrode body, characterized in that the negative electrode body is prepared from the silicon negative electrode slurry according to any one of claims 1 to 8.
10. A lithium ion battery comprising a positive plate, a negative plate and an electrolyte, wherein the negative plate is the silicon negative plate of claim 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310732169.5A CN117174830A (en) | 2023-06-20 | 2023-06-20 | Preparation methods of negative electrode slurry, negative electrode sheet and battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310732169.5A CN117174830A (en) | 2023-06-20 | 2023-06-20 | Preparation methods of negative electrode slurry, negative electrode sheet and battery |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117174830A true CN117174830A (en) | 2023-12-05 |
Family
ID=88934409
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310732169.5A Pending CN117174830A (en) | 2023-06-20 | 2023-06-20 | Preparation methods of negative electrode slurry, negative electrode sheet and battery |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117174830A (en) |
-
2023
- 2023-06-20 CN CN202310732169.5A patent/CN117174830A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110600671B (en) | Semi-dry method batching process of lithium ion battery electrode slurry, lithium ion battery positive plate, battery negative plate and lithium ion battery | |
| CN110797536A (en) | Lithium ion battery anode slurry and preparation method thereof and lithium ion battery | |
| CN110993884B (en) | Lithium ion battery negative electrode slurry, preparation method, negative electrode plate and battery | |
| CN113659125B (en) | Silicon-carbon composite material and preparation method thereof | |
| EP4116355A1 (en) | Composite polymer, and preparation method therefor and application thereof | |
| CN115513515B (en) | Secondary battery and preparation method thereof | |
| CN112072113B (en) | Electrode thickener and negative electrode slurry using same | |
| CN115566179A (en) | High-energy-density lithium ion battery silicon-based negative electrode composite slurry and preparation method thereof | |
| CN111370642A (en) | Conductive coating material based on graphene quantum dots and derivatives thereof and application thereof | |
| CN111540886B (en) | Negative electrode material, preparation method thereof and multilayer electrode | |
| WO2021184222A1 (en) | Conductive coating material based on graphene quantum dots and derivatives thereof, and use thereof | |
| CN113921756A (en) | Silicon-carbon negative electrode piece with high silicon content and preparation method thereof | |
| CN117174830A (en) | Preparation methods of negative electrode slurry, negative electrode sheet and battery | |
| CN115528204A (en) | Negative plate, preparation method thereof and lithium ion battery | |
| CN116417609A (en) | Positive electrode slurry of sodium ion battery and preparation method and application thereof | |
| CN114497440A (en) | Negative plate and battery comprising same | |
| CN114649503A (en) | Lithium battery silicon-carbon negative plate and preparation method thereof | |
| CN114361416A (en) | Silicon-based composite material, lithium ion battery and preparation method and application thereof | |
| CN112952029A (en) | Silica-carbon lithium ion battery composite negative electrode slurry, preparation method thereof and lithium ion battery negative electrode prepared from silica-carbon lithium ion battery composite negative electrode slurry | |
| CN112713265A (en) | Composite conductive binder suitable for silicon-based negative electrode, preparation method and application | |
| CN116190660B (en) | Adhesive, preparation method and application thereof, silicon-based negative electrode and preparation method thereof | |
| CN116259738B (en) | Nano silicon-carbon composite negative electrode material, preparation method and lithium ion battery | |
| CN111029586B (en) | High-rate lithium ion battery anode slurry | |
| CN117174910A (en) | Water-based negative electrode slurry and preparation method and application thereof | |
| CN113666354B (en) | Preparation method of silicon-carbon composite material, silicon negative electrode piece and battery |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |