CN115513459A - Organic mixed conductor and preparation method and application thereof - Google Patents

Organic mixed conductor and preparation method and application thereof Download PDF

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CN115513459A
CN115513459A CN202211176159.XA CN202211176159A CN115513459A CN 115513459 A CN115513459 A CN 115513459A CN 202211176159 A CN202211176159 A CN 202211176159A CN 115513459 A CN115513459 A CN 115513459A
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lithium
mixed conductor
organic mixed
thiophene
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杨冰筱
沈炎宾
陈立桅
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Suzhou Institute of Nano Tech and Nano Bionics of CAS
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Abstract

The invention provides an organic mixed conductor and a preparation method and application thereof, wherein the organic mixed conductor comprises lithium salt and poly (3-monomethoxypolyethylene glycol) thiophene shown as a general formula 1. The organic mixed conductor provided by the invention has good electronic and ionic conductivity and certain cohesiveness, can replace polyvinylidene fluoride and conductive carbon in the traditional anode, and ensures the mass ratio of the anode active substance; according to the invention, the modulation of the ionic and electronic conductivity of the organic mixed conductor can be realized by adjusting the length of the side chain in the poly (3-monomethoxypolyethylene glycol) thiophene shown in the general formula 1 and the polymerization degree of the main chain, so that the anodes of solid lithium secondary batteries with different performances can be prepared; compared with the traditional vinylidene fluoride/conductive carbon/anode active material anode, the organic mixed conductor provided by the invention is used for the anode of the solid-state lithium secondary battery, and can remarkably improve the cycle performance of the solid-state lithium secondary battery.

Description

Organic mixed conductor and preparation method and application thereof
Technical Field
The invention belongs to the technical field of lithium batteries, relates to an organic mixed conductor and a preparation method and application thereof, and particularly relates to an organic mixed conductor and a preparation method thereof, a positive pole piece and a solid-state lithium secondary battery.
Background
For the traditional liquid lithium ion battery, the demand of the society for an energy storage device with higher energy density and safety is difficult to meet by simply depending on the optimization of the battery structure and the preparation process. Thus, the development of next-generation battery chemistry systems has become a must route to the production of batteries with high specific energy and safety. Among them, rechargeable lithium metal batteries using metallic lithium as a negative electrode in combination with a high-voltage positive electrode material are considered to be one of the most promising high-energy-density energy storage devices. However, conventional electrolytes can lead to lithium pulverization and uncontrolled under electrochemical conditions leading to the formation of lithium dendrites and dead lithium generation. In contrast, a solid lithium secondary battery using a solid electrolyte is excellent in overcoming the above problems. However, the conventional positive electrode plate prepared by using polyvinylidene fluoride/conductive carbon/positive active material belongs to a solid porous electrode. In a liquid lithium ion battery, good electron and ion transmission can be realized only by virtue of the wetting of the electrolyte on the positive pole piece. However, for a solid lithium secondary battery, the contact of the solid electrolyte with the positive electrode sheet is a solid-solid contact. Since the ion conductivity of the commonly used polyvinylidene fluoride and other binders is very low, except for the active material part of the surface layer of the positive electrode plate, which is in contact with the solid electrolyte, the lithium ion transmission of most active materials in the inner layer of the positive electrode plate is difficult, and the overall performance of the solid lithium secondary battery is further influenced. The method of directly adding the ionic conductive agent into the original positive electrode slurry can not only reduce the mass ratio of the active material in the positive electrode plate, but also can not ensure that the ionic conductivity of the positive electrode plate can be obviously improved.
Therefore, for the solid-state lithium secondary battery, the component structure of the positive electrode plate needs to be reconfigured. The aim of the blending is to ensure the positive pole piece to have higher ionic conductivity on the premise of ensuring the mass ratio of active substances in the positive pole piece.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide an organic mixed conductor and a preparation method and application thereof, and particularly provides the organic mixed conductor, the preparation method thereof, a positive pole piece and a solid-state lithium secondary battery. The organic mixed conductor provided by the invention comprises a monomethoxy polyethylene glycol grafted polythiophene polymer and lithium salt, has good ion/electron conductivity, and has good adhesion capacity to a positive electrode active material and a current collector. Compared with the traditional polyvinylidene fluoride/conductive carbon/positive active material, the solid-state lithium secondary battery assembled by the positive pole piece prepared from the organic mixed conductor/positive active material has higher battery cycle performance.
In order to achieve the purpose, the invention adopts the following technical scheme:
in a first aspect, the present invention provides an organic mixed conductor comprising a lithium salt and a poly (3-monomethoxypolyethylene glycol) thiophene of formula 1:
Figure BDA0003864507380000021
in formula 1, m is the number of repeating units in the polymer chain, m is an integer from 1 to 100 (e.g., 1, 3, 5, 8, 10, 13, 15, 18, 20, 23, 25, 28, 30, 33, 35, 38, 40, 43, 45, 48, 50, 53, 55, 58, 60, 63, 65, 68, 70, 73, 75, 78, 80, 83, 85, 88, 90, 93, 95, 98, or 100, etc.), n is the number of ethoxy repeating units, and n is an integer from 1 to 8 (e.g., 1, 2, 3, 4, 5, 6, 7, or 8).
The organic mixed conductor provided by the invention has good electronic and ionic conductivity and certain cohesiveness, can replace polyvinylidene fluoride and conductive carbon in the traditional anode, and ensures the mass ratio of the anode active substance; according to the invention, the modulation of the ionic and electronic conductivity of the organic mixed conductor can be realized by adjusting the length of the side chain in the poly (3-monomethoxypolyethylene glycol) thiophene shown in the general formula 1 and the polymerization degree of the main chain, so that the anodes of solid lithium secondary batteries with different performances can be prepared; compared with the conventional vinylidene fluoride/conductive carbon/anode active material anode, the organic mixed conductor provided by the invention is used for the anode of the solid-state lithium secondary battery, and can remarkably improve the cycle performance of the solid-state lithium secondary battery.
Preferably, the poly (3-monomethoxypolyethylene glycol) thiophene shown in the general formula 1 is a protonic acid catalyzed polymerization product of a 3-monomethoxypolyethylene glycol thiophene monomer.
Preferably, the poly (3-monomethoxypolyethylene glycol) thiophene shown in the general formula 1 is prepared by the following preparation method:
(1) 3-methoxy thiophene reacts with poly (ethylene glycol) terminated by oligomeric monomethoxy to generate a 3-monomethoxy poly (ethylene glycol) thiophene monomer;
(2) And carrying out polymerization reaction on the 3-monomethoxypolyethylene glycol thiophene monomer to obtain the poly (3-monomethoxypolyethylene glycol) thiophene.
The preparation route is as follows:
Figure BDA0003864507380000031
preferably, the molar ratio of the 3-methoxythiophene to the oligomeric monomethoxy terminated polyethylene glycol in step (1) is 1 (1-4), such as 1.
Preferably, the catalyst for the reaction of step (1) comprises sodium bisulfate.
Preferably, the catalyst for the polymerization reaction of step (2) comprises a protic acid.
Preferably, the protonic acid includes any one of hydrogen chloride, sulfuric acid, nitric acid, formic acid, acetic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, or heteropolyacids (e.g., phosphotungstic acid, etc.), or a combination of at least two thereof.
Preferably, n is an integer from 3 to 6.
Preferably, the lithium salt includes lithium difluorophosphate (LiPF) 2 O 2 ) Lithium hexafluorophosphate (LiPF) 6 ) Lithium perchlorate (LiClO) 4 ) Lithium tetrafluoroborate (LiBF) 4 ) Lithium hexafluoroborate (LiBF) 6 ) Lithium trifluoromethanesulfonate (LiCF) 3 SO 3 ) Lithium hexafluoroarsenate (LiAsF) 6 ) Lithium bis (trifluoromethylsulfonyl imide) (LiTFSI), lithium bis (difluorosulfonyl imide) (LiFSI), lithium bis (oxalato) borate (LiBOB), lithium difluoro (oxalato) borate (lidob), or lithium malonato oxalato borate (LiMOB).
Preferably, the molar ratio of the lithium salt to the ethoxy group in the poly (3-monomethoxypolyethylene glycol) thiophene represented by the general formula 1 is 1-1.
In a second aspect, the present invention provides a method for preparing the organic mixed conductor of the first aspect, the method comprising the steps of:
dissolving poly (3-monomethoxypolyethylene glycol) thiophene shown as a general formula 1 in an organic solvent, adding lithium salt, and removing the organic solvent to obtain the organic mixed conductor.
Preferably, the organic solvent comprises chloroform.
Or mixing poly (3-monomethoxypolyethylene glycol) thiophene shown as a general formula 1 with lithium salt, and carrying out solid phase grinding to obtain the organic mixed conductor.
In a third aspect, the present invention provides a positive electrode plate, comprising a current collector and a coating disposed on the current collector, wherein the material of the coating comprises a positive active material and the organic mixed conductor according to the first aspect.
Preferably, the positive electrode active material contains any one or a combination of at least two of lithium, iron, cobalt, nickel, manganese, aluminum or phosphorus elements, wherein the positive electrode active material is doped or coated with one or at least two of aluminum, magnesium, zirconium, titanium, scandium, lanthanum, nickel, manganese, yttrium or strontium elements.
Preferably, the positive active material includes any one of or a combination of at least two of lithium iron phosphate (LFP), lithium manganese iron phosphate, lithium Cobaltate (LCO), lithium manganate, a nickel cobalt manganese ternary electrode material (NCM 111, 523, 622, 811), a nickel cobalt aluminum ternary electrode material, or a lithium-rich manganese-based material.
Preferably, the weight percentage of the organic mixed conductor is 2.5-40%, such as 2.5%, 5%, 8%, 10%, 15%, 18%, 20%, 25%, 28%, 30%, 35%, 38%, 40%, or the like, based on the total weight of the positive electrode active material and the organic mixed conductor taken as 100%.
Preferably, the positive pole piece is prepared by the following method:
dissolving an organic mixed conductor in an organic solvent, adding a positive active material to obtain mixed slurry, coating the mixed slurry on a current collector, drying and rolling to obtain the positive pole piece.
Preferably, the organic solvent comprises N-methylpyrrolidone.
Or mixing the organic mixed conductor and the positive active material, grinding to obtain a grinding material, and compounding the grinding material on a current collector to obtain the positive pole piece.
In a fourth aspect, the present invention provides a solid-state lithium secondary battery, including a positive electrode plate, a solid-state electrolyte, and a negative electrode plate, where the positive electrode plate is the positive electrode plate of the third aspect.
Preferably, the solid electrolyte is selected from any one of a polymer solid electrolyte, an inorganic solid electrolyte, or an organic-inorganic composite solid electrolyte.
Preferably, the active material of the negative electrode plate comprises any one of carbon-based material, silicon-based material, boron-based material, metal lithium, metal bismuth, nitride, magnesium-based alloy, transition metal oxide or phosphide or a combination of at least two of the above materials.
The above-mentioned preferred conditions can be freely combined on the basis of the common general knowledge in the field without departing from the scope of the present invention.
Compared with the prior art, the invention at least has the following beneficial effects:
(1) The invention mainly solves the problem of ion transmission between a porous solid positive electrode prepared from the traditional polyvinylidene fluoride/conductive carbon/positive electrode active material and a solid electrolyte, and the problem limits the surface loading of a positive electrode active substance in the traditional solid lithium secondary battery.
(2) According to the invention, the modulation of the ionic and electronic conductivity of the organic mixed conductor can be realized by adjusting the length of the side chain in the poly (3-monomethoxypolyethylene glycol) thiophene shown in the general formula 1 and the polymerization degree of the main chain, so that the anodes of solid lithium secondary batteries with different performances can be prepared.
(3) Compared with the traditional vinylidene fluoride/conductive carbon/anode active material anode, the organic mixed conductor designed and synthesized by the invention is used for the anode of the solid-state lithium secondary battery, and can remarkably improve the cycle performance of the solid-state lithium secondary battery (the first cycle efficiency is 80.2-87.5%, and the capacity retention rate of 300 circles is 81-91%).
Detailed Description
The technical solution of the present invention is further described below by way of specific embodiments. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitation of the present invention.
Example 1
In this example, an organic mixed conductor is provided that includes a lithium salt and poly (3-monomethoxypolyethylene glycol) thiophene as shown below:
Figure BDA0003864507380000061
the preparation method comprises the following steps:
(1) Under the atmosphere of nitrogen, 8 g of 3-methoxy thiophene is weighed and placed in a round-bottom flask, 50 ml of toluene is added to be stirred and dissolved at room temperature, then 17.2 g of monomethoxy triethylene glycol and 2.6 g of sodium bisulfate are added into the solution, and the reaction solution is refluxed for 72 hours to obtain 11.7 g of 3-monomethoxy trimeric ethylene glycol-based thiophene monomer.
(2) Taking 6 g of 3-monomethoxy trimeric ethylene glycol thiophene monomer, adding 0.6 g of p-toluenesulfonic acid, reacting for 24h at room temperature, adding methanol, and washing for multiple times to obtain poly (3-monomethoxy trimeric ethylene glycol) thiophene precipitate.
(3) 5 g of poly (3-monomethoxy-triethylene glycol) thiophene was dissolved in 20 ml of chloroform, 1.1 g of LiTFSI was added and stirred, and the chloroform was removed to obtain a dark organic mixed conductor.
Example 2
In this example, an organic mixed conductor is provided that includes a lithium salt and poly (3-monomethoxypolyethylene glycol) thiophene as shown below:
Figure BDA0003864507380000071
the preparation method comprises the following steps:
(1) Under nitrogen atmosphere, weighing 8 g of 3-methoxy thiophene, placing the 3-methoxy thiophene in a round-bottom flask, adding 70 ml of toluene, stirring and dissolving at room temperature, then adding 21.8 g of monomethoxy tetraethylene glycol and 3.0 g of sodium bisulfate into the solution, and refluxing the reaction solution for 72 hours to obtain 14.7 g of 3-monomethoxy tetraethylene glycol thiophene monomer.
(2) Taking 6 g of 3-monomethoxy tetraethylene glycol thiophene monomer, adding 0.6 g of trifluoromethanesulfonic acid, reacting at room temperature for 24h, adding methanol, and washing for multiple times to obtain poly (3-monomethoxy tetraethylene glycol group) thiophene dark precipitate.
(3) 5 g of poly (3-monomethoxy-tetraethylene glycol) thiophene is dissolved in 35 ml of chloroform, 1.5 g of LiFSI is added and stirred, and the chloroform is removed to obtain a dark organic mixed conductor.
Example 3
In this example, an organic mixed conductor is provided that includes a lithium salt and poly (3-monomethoxypolyethylene glycol) thiophene as shown below:
Figure BDA0003864507380000081
the preparation method comprises the following steps:
(1) Under nitrogen atmosphere, 4 g of 3-methoxy thiophene is weighed and placed in a round-bottom flask, 80 ml of toluene is added to be stirred and dissolved at room temperature, then 15.5 g of monomethoxyhexapolyethylene glycol and 2.0 g of sodium bisulfate are added into the solution, and the reaction solution is refluxed for 72 hours to obtain 9.3 g of 3-monomethoxyhexapolyethylene glycol thiophene monomer.
(2) Taking 5 g of 3-monomethoxyhexapolyethylene glycol thiophene monomer, adding 0.5 g of phosphotungstic acid, reacting at room temperature for 24h, adding methanol, and washing for multiple times to obtain poly (3-monomethoxyhexapolyethylene glycol) thiophene precipitate.
(3) 5 g of poly (3-monomethoxyhexaethyleneglycol) thiophene was dissolved in 45 ml of chloroform, 1.1 g of LiDFOB was added thereto and stirred, and chloroform was removed to obtain a dark colored organic mixed conductor.
Comparative example 1
This comparative example differs from example 1 only in that
Figure BDA0003864507380000082
By replacing with equimolar amounts
Figure BDA0003864507380000083
Comparative example 2
This comparative example differs from example 1 only in that
Figure BDA0003864507380000084
By replacing with equimolar amounts
Figure BDA0003864507380000085
Application examples 1 to 8
A positive pole piece comprises a current collector (aluminum foil) and a coating arranged on the current collector, wherein the coating comprises a positive active material and an organic mixed conductor provided by examples 1-3, the positive active material and the organic mixed conductor used in application examples 1-8 are calculated by taking the total weight of the positive active material and the organic mixed conductor as 100%, and the weight percentage of the organic mixed conductor is specifically shown in Table 1.
The preparation methods of the positive electrode sheets provided in application examples 1 to 8 are shown in table 1.
TABLE 1
Figure BDA0003864507380000091
In table 1, (1) the slurry coating method specifically includes the following steps: dissolving an organic mixed conductor in N-methyl pyrrolidone, adding a positive active material to obtain mixed slurry, coating the mixed slurry on a current collector, drying in vacuum, and rolling to obtain the positive pole piece. The mixing and grinding method (2) comprises the following steps: and mixing the organic mixed conductor and the positive active material, grinding to obtain a grinding material, and compounding the grinding material on a current collector to obtain the positive pole piece. (3) The inorganic solid electrolyte is LLZTO, and the polymer solid electrolyte is Polyoxyethylene (PEO).
Application examples 1 to 8 also provide a solid-state lithium secondary battery, respectively, including a positive electrode tab, a solid-state electrolyte, and a negative electrode tab, where the positive electrode tab and the solid-state electrolyte are shown in table 1, respectively; the preparation method of the solid-state lithium secondary battery comprises the following steps:
(1) Positive pole piece: as shown in table 1;
(2) Solid electrolyte: as shown in table 1;
(3) And (3) negative plate: a metallic lithium sheet having a thickness of 0.25 mm;
(4) Assembly of solid-state lithium secondary battery: and assembling the prepared positive pole piece, solid electrolyte and negative pole piece into a 5Ah soft package battery (assembling the negative pole and the positive pole in a matching way according to N/P = 1.1).
Comparative application example 1
This comparative application example differs from application example 1 only in that the organic mixed conductor provided in example 1 was replaced with the same weight percentage (85%) of polyvinylidene fluoride and conductive carbon (wherein the weight ratio of polyvinylidene fluoride to conductive carbon was 1.7.
Comparative application example 2
This comparative application example differs from application example 3 only in that the organic mixed conductor provided in example 2 was replaced with the same weight percentage (85%) of polyvinylidene fluoride and conductive carbon (wherein the weight ratio of polyvinylidene fluoride to conductive carbon was 1.8.
Comparative application example 3
This comparative application example differs from application example 5 only in that the organic mixed conductor provided in example 3 was replaced with the same weight percentage (85%) of polyvinylidene fluoride and conductive carbon (wherein the weight ratio of polyvinylidene fluoride to conductive carbon was 1.1.6).
Comparative application example 4
This comparative application example differs from application example 1 only in that the organic mixed conductor provided in example 1 was replaced with the organic mixed conductor provided in comparative example 1.
Comparative application example 5
This comparative application example differs from application example 1 only in that the organic mixed conductor provided in example 1 was replaced with the organic mixed conductor provided in comparative example 2.
And (3) carrying out performance test on the solid-state lithium secondary battery provided by the application example and the comparative application example, wherein the test method comprises the following steps: the battery adopts a constant current-constant potential charging/constant current discharging mode, the charging and discharging cutoff voltage is respectively 4.20V and 2.75V, the constant potential cutoff current is 0.02C, standing is carried out for 30min between each cycle of charging and discharging, and the battery is subjected to cycle test at 60 ℃ at the charging and discharging multiplying power of 0.1C/0.5C.
The results of the performance tests are shown in table 2.
TABLE 2
First week efficiency (%) Capacity retention at 300 cycles (%)
Application example 1 86.5 91
Application example 2 85.7 89
Application example 3 84.3 87
Application example 4 87.2 85
Application example 5 85.7 86
Application example 6 83.5 85
Application example 7 80.2 81
Application example 8 87.5 90
Comparative application example 1 72.6 76
Comparative application example 2 70.5 73
Comparative application example 3 67.3 64
Comparative application example 4 71.4 65
Comparative application example 5 78.5 75
As can be seen from Table 2, the solid-state lithium secondary batteries provided in application examples 1 to 8 of the present invention all had high first-cycle efficiencies (80.2% to 87.5%) and capacity retention rates (81% to 91%) of 300 cycles.
As can be seen from the comparison between application example 1 and comparative application example 1, application example 3 and comparative application example 2, and application example 5 and comparative application example 3, the organic mixed conductor provided by the present invention can significantly improve the cycle performance of the solid-state lithium secondary battery.
The first-cycle efficiency and 300-cycle capacity retention rate of the solid-state lithium secondary batteries provided in comparative application examples 4 to 5 were significantly reduced as compared with application example 1.
The applicant states that the present invention is illustrated by the above examples of the organic mixed conductor of the present invention and the preparation method and application thereof, but the present invention is not limited to the above examples, i.e. it does not mean that the present invention must be implemented by the above examples. It should be understood by those skilled in the art that any modification of the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.

Claims (10)

1. An organic mixed conductor comprising a lithium salt and a poly (3-monomethoxypolyethylene glycol) thiophene of the formula 1:
Figure FDA0003864507370000011
in the general formula 1, m is an integer of 1-100, and n is an integer of 1-8.
2. The organic mixed conductor according to claim 1, characterized in that the poly (3-monomethoxypolyethylene glycol) thiophene of the general formula 1 is a protonic acid catalyzed polymerization product of a 3-monomethoxypolyethylene glycol thiophene monomer;
preferably, the poly (3-monomethoxypolyethylene glycol) thiophene shown in the general formula 1 is prepared by the following preparation method:
(1) 3-methoxy thiophene reacts with poly (ethylene glycol) terminated by oligomeric monomethoxy to generate a 3-monomethoxy poly (ethylene glycol) thiophene monomer;
(2) And carrying out polymerization reaction on the 3-monomethoxypolyethylene glycol thiophene monomer to obtain the poly (3-monomethoxypolyethylene glycol) thiophene.
3. The organic mixed conductor of claim 2, wherein the molar ratio of the 3-methoxythiophene to the oligomeric monomethoxy terminated polyethylene glycol in step (1) is 1 (1-4);
preferably, the catalyst for the reaction of step (1) comprises sodium bisulfate;
preferably, the catalyst for the polymerization reaction of step (2) comprises a protonic acid;
preferably, the protic acid comprises any one of hydrogen chloride, sulphuric acid, nitric acid, formic acid, acetic acid, trifluoromethanesulphonic acid, p-toluenesulphonic acid or a heteropolyacid or a combination of at least two thereof.
4. The organic mixed conductor according to any of claims 1 to 3, wherein n is an integer of 3 to 6.
5. The organic mixed conductor according to any one of claims 1 to 4, wherein the lithium salt comprises any one of lithium difluorophosphate, lithium hexafluorophosphate, lithium perchlorate, lithium tetrafluoroborate, lithium hexafluoroborate, lithium trifluoromethanesulfonate, lithium hexafluoroarsenate, lithium bis (trifluoromethylsulfonimide), lithium bis (difluorosulfonimide), lithium dioxalate, lithium oxalato borate, or lithium malonato oxalato borate, or a combination of at least two thereof;
preferably, the molar ratio of the lithium salt to the ethoxy groups in the poly (3-monomethoxypolyethylene glycol) thiophene of formula 1 is 1.
6. The method of preparing an organic mixed conductor according to any of claims 1-5, comprising the steps of:
dissolving poly (3-monomethoxypolyethylene glycol) thiophene shown in a general formula 1 in an organic solvent, adding lithium salt, and removing the organic solvent to obtain the organic mixed conductor;
or mixing poly (3-monomethoxypolyethylene glycol) thiophene shown as a general formula 1 with lithium salt, and carrying out solid phase grinding to obtain the organic mixed conductor.
7. A positive electrode sheet comprising a current collector and a coating layer disposed on the current collector, wherein the material of the coating layer comprises a positive active material and the organic mixed conductor according to any one of claims 1 to 5.
8. The positive electrode plate as claimed in claim 7, wherein the positive active material comprises any one or a combination of at least two of lithium iron phosphate, lithium manganese iron phosphate, lithium cobaltate, lithium manganate, nickel cobalt manganese ternary electrode material, nickel cobalt aluminum ternary electrode material, or lithium rich manganese-based material;
preferably, the organic mixed conductor is 2.5 to 40% by weight based on 100% by weight of the total weight of the positive electrode active material and the organic mixed conductor.
9. The positive electrode plate according to claim 7 or 8, wherein the positive electrode plate is prepared by the following method:
dissolving an organic mixed conductor in an organic solvent, then adding a positive active material to obtain mixed slurry, coating the mixed slurry on a current collector, drying and rolling to obtain the positive pole piece;
or mixing the organic mixed conductor and the positive active material, grinding to obtain a grinding material, and compounding the grinding material on a current collector to obtain the positive pole piece.
10. A solid-state lithium secondary battery comprising a positive electrode sheet, a solid-state electrolyte and a negative electrode sheet, wherein the positive electrode sheet is the positive electrode sheet according to any one of claims 7 to 9.
CN202211176159.XA 2022-09-26 2022-09-26 Organic mixed conductor and preparation method and application thereof Pending CN115513459A (en)

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