CN115172674A - Lithium iron phosphate anode, preparation method and battery comprising same - Google Patents

Lithium iron phosphate anode, preparation method and battery comprising same Download PDF

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CN115172674A
CN115172674A CN202211039617.5A CN202211039617A CN115172674A CN 115172674 A CN115172674 A CN 115172674A CN 202211039617 A CN202211039617 A CN 202211039617A CN 115172674 A CN115172674 A CN 115172674A
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lithium iron
iron phosphate
anode
coupling agent
carbon black
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徐吉静
韩锰
王晓雪
梁爽
王悦
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Jilin University
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Jilin University
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/136—Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H01M4/1397—Processes of manufacture of electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/362—Composites
    • H01M4/366—Composites as layered products
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/624—Electric conductive fillers
    • H01M4/625—Carbon or graphite
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/028—Positive electrodes
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Abstract

The invention is suitable for the technical field of lithium ion batteries, and provides a preparation method of a lithium iron phosphate anode, which comprises the following steps: mixing and grinding lithium iron phosphate, a silane coupling agent, ethanol, carbon black, a binder and a solvent to obtain uniform slurry; coating the slurry on a metal aluminum foil to form a smooth coating; drying the coating on the metal aluminum foil, and removing the solvent to obtain the lithium iron phosphate anode material; cutting the lithium iron phosphate anode material, and dehydrating and drying in vacuum to obtain the lithium iron phosphate anode. The invention also provides a lithium iron phosphate anode and a battery comprising the same. According to the invention, the silane coupling agent is modified on the lithium iron phosphate, so that the silane coupling agent and the conductive carbon black generate a chemical combination effect, the three-dimensional conductive ionic integrated network is constructed, the battery performance is improved, and meanwhile, the stable organic-inorganic composite interface layer can be generated by the reaction of the electrolyte and the lithium iron phosphate modified with the silane coating, so that the lithium iron phosphate is firm and stable and has super-strong lithium ion conductivity.

Description

Lithium iron phosphate anode, preparation method and battery comprising same
Technical Field
The invention belongs to the technical field of lithium ion batteries, and particularly relates to a lithium iron phosphate anode, a preparation method and a battery comprising the same.
Background
The lithium iron phosphate positive electrode material is widely applied to lithium ion batteries and is the most suitable positive electrode material except for ternary lithium positive electrodes, but the lithium iron phosphate positive electrode material also encounters some practical problems in the batteries, in a charging high voltage area, an electrolyte can react with the positive electrode to generate a layer of CEI film, the stability of the CEI film directly influences the cycle stability of the batteries, in addition, the binding force problem between an active substance (lithium conducting) and conductive carbon black (conductive) in the positive electrode is also always an important problem for research, in the preparation of the traditional battery pole piece, the active substance and the conductive carbon black only have physical contact without the action of chemical binding force, so that a three-dimensional conductive ionic network is difficult to construct, and further, the battery performance is poor.
In order to solve the problem, various improved means are developed, and from the perspective of the binder, the lithium iron phosphate and the conductive carbon black are fully bonded together; secondly, lithium iron phosphate is modified, a layer of carbon is coated outside the lithium iron phosphate to improve the defect of low electronic conductivity of the lithium iron phosphate, however, the improvement means has very limited performance improvement, so that a lithium iron phosphate anode is urgently needed, a three-dimensional conductive ion network of the anode can be realized, the rapid ionic-electronic conduction of an anode active substance and conductive carbon under the condition of high-rate long circulation can be realized, and the problems of volume expansion and pulverization of the active substance caused by long-time charging and discharging are solved.
Disclosure of Invention
An embodiment of the present invention provides a method for preparing a lithium iron phosphate positive electrode, which aims to solve the problems in the background art.
The embodiment of the invention is realized in such a way that the preparation method of the lithium iron phosphate anode comprises the following steps:
mixing and grinding lithium iron phosphate, a silane coupling agent, ethanol, carbon black, a binder and a solvent to obtain uniform slurry;
coating the slurry on a metal aluminum foil to form a smooth coating;
drying the coating on the metal aluminum foil, and removing the solvent to obtain the lithium iron phosphate anode material;
cutting the lithium iron phosphate anode material, and drying by vacuum dewatering to obtain the lithium iron phosphate anode.
Preferably, the lithium iron phosphate: silane coupling agent: ethanol: the mass ratio of the carbon black is 10;
the lithium iron phosphate: the mass ratio of the binder is 8;
the ethanol: the mass ratio of the solvent is 1.
Preferably, the silane coupling agent is one or more of triaminopropyltriethoxysilane, tricyanopropyltriethoxysilane and trivinyltriethoxysilane;
including but not limited to the above-mentioned raw materials, the requirement for the terminal group of the silane coupling agent is mainly that the terminal group is capable of reacting with the functional group on the surface of the conductive carbon black.
Preferably, the binder is PVDF;
the solvent is NMP.
Preferably, the slurry obtained by mixing and grinding lithium iron phosphate, a silane coupling agent, ethanol, carbon black, a binder and a solvent to be uniform specifically comprises the following steps:
adding lithium iron phosphate, a silane coupling agent and ethanol into a vortex apparatus for fully mixing, and then adding conductive carbon black, a binder and a solvent into the mixture for vortex until uniform slurry is obtained.
Preferably, the step of mixing and grinding the lithium iron phosphate, the silane coupling agent, the ethanol, the carbon black, the binder and the solvent to obtain uniform slurry comprises the following steps:
adding conductive carbon black, a silane coupling agent and ethanol into a vortex instrument for fully mixing, and then adding lithium iron phosphate, a binder and a solvent into the mixture for vortex until uniform slurry is obtained.
Preferably, the slurry obtained by mixing and grinding lithium iron phosphate, a silane coupling agent, ethanol, carbon black, a binder and a solvent to be uniform specifically comprises the following steps:
and sequentially adding the lithium iron phosphate, the conductive carbon black, the silane coupling agent, the binder, the ethanol and the solvent into a vortex instrument for fully mixing until uniform slurry is obtained.
Preferably, the metal aluminum foil is 4 × 4cm;
and cutting the lithium iron phosphate anode material to obtain a circular sheet with the diameter of 12 mm.
Another object of the embodiment of the invention is to provide a lithium iron phosphate positive electrode prepared by the above preparation method.
Another object of an embodiment of the present invention is to provide a battery including the lithium iron phosphate positive electrode, the battery further including:
a negative electrode;
a diaphragm;
and (3) an electrolyte.
According to the lithium iron phosphate anode provided by the embodiment of the invention, a silane coupling agent is modified on the common lithium iron phosphate of the lithium ion battery anode, so that the silane coupling agent and conductive carbon black are chemically combined to form a three-dimensional conductive ionic integrated network, the battery performance is improved, meanwhile, the silane coating can also play a role in protecting the lithium iron phosphate anode, an electrolyte and the lithium iron phosphate modified with the silane coating react to generate a stable organic-inorganic composite interface layer, and the CEI film on the layer is firm and stable and has super-strong lithium ion conductivity, so that the stability of the lithium iron phosphate battery is greatly improved, specifically:
after the silane is modified on the lithium iron phosphate anode, the lithium iron phosphate anode and the conductive carbon black generate a chemical combination effect, so that the interface compatibility of the lithium iron phosphate anode and the conductive carbon black is improved, and a three-dimensional network of conductive ions is effectively constructed;
the silane-modified lithium iron phosphate reacts with the electrolyte to generate a stable and firm organic-inorganic composite interface film, so that charging and discharging can be stably carried out, and the cycling stability of the battery is improved;
the silane layer can effectively bond lithium iron phosphate and conductive carbon black, so that the rapid transmission of ionic electrons is realized, and the multiplying power performance of the battery is better facilitated.
Drawings
Fig. 1 is a schematic diagram of lithium iron phosphate-silane-carbon black provided in an embodiment of the present invention;
fig. 2 is an SEM test chart of a lithium iron phosphate positive electrode provided in embodiment 1 of the present invention;
fig. 3 is an SEM test chart of the lithium iron phosphate positive electrode not modified with the silane coupling agent according to comparative example 1 of the present invention;
fig. 4 is a graph of test data for the Land system of the battery provided in example 1 and comparative example 1 of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention.
The silane coupling agent is used as an organic-inorganic composite bonding material and can well bond lithium iron phosphate and conductive carbon black, a group at the end group of the silane coupling agent, such as an amino group and the like, can well react with a functional group on the surface of the conductive carbon black so as to generate a better chemical bonding effect, a hydroxyl group generated by hydrolysis of siloxane groups can well condense with a hydroxyl group on the surface of the lithium iron phosphate so as to generate a strong chemical bonding effect, a network constructed by the silane coupling agent has abundant oxygen and nitrogen atoms, can well play a role in conducting ions, and the carbon black network obtained by connection can also play a role in continuously obtaining the conducting ions, so that a three-dimensional conducting ion-conducting channel is realized;
the existing method for improving the anode can not meet the requirement that lithium iron phosphate can keep good performance under the condition of long-time high rate, and the silane coupling agent not only meets the requirement of a three-dimensional conductive ion network of the anode, but also meets the requirement of realizing the anode with no expansion and high mechanical property, thereby thoroughly solving the problem that the lithium iron phosphate can not stably run under the condition of high rate long circulation;
the schematic diagram of the silane-coupled lithium iron phosphate and the conductive carbon black is shown in fig. 1:
wherein, the siloxy group of the silane layer and the amino group at the chain end can form good interaction with lithium ions, thereby being beneficial to the conduction of the ions; the silane is effectively connected with the lithium iron phosphate and the conductive carbon black, so that the simple physical connection of the lithium iron phosphate and the carbon black is changed into the chemical bonding effect; the three-dimensional conductive ionic network of the lithium iron phosphate-silane-carbon black effectively promotes the migration of positive ions and electrons.
Specific implementations of the present invention are described in detail below with reference to specific embodiments.
Example 1
A preparation method of a lithium iron phosphate anode comprises the following steps:
lithium iron phosphate, triaminopropyltriethoxysilane and an ethanol solution are mixed according to the mass ratio of 10:1:20, then adding carbon black (the mass is 1/8 of that of the lithium iron phosphate) into the mixture, and fully stirring and mixing the mixture;
adding a binder PVDF (the mass is 1/8 of that of the lithium iron phosphate) and a solvent NMP (the mass ratio of ethanol to NMP is 1;
then drying to remove solvent NMP, cutting the lithium iron positive plate into a wafer with the diameter of 12mm, and carrying out vacuum dehydration and drying;
the assembly method of the battery containing the lithium iron phosphate positive electrode comprises the following steps:
and placing the lithium iron phosphate anode in a glove box, carrying out the whole battery assembly process in the glove box with the water oxygen content lower than 0.1ppm, sequentially arranging a cathode shell, an elastic sheet, a gasket, metal, a diaphragm, electrolyte, an anode and an anode shell according to the assembly sequence from the cathode to the anode, and then placing the cathode shell, the anode and the anode in a tablet press to press the cathode into the CR2032 button battery.
Example 2
A preparation method of the lithium iron phosphate anode comprises the following steps:
lithium iron phosphate, tricyanopropyltriethoxysilane and ethanol solution are mixed according to the mass ratio of 10:1:20, fully mixing, then adding carbon black (the mass is 1/8 of that of the lithium iron phosphate), and fully stirring and mixing;
adding a binder PVDF (the mass is 1/8 of that of the lithium iron phosphate) and a solvent NMP (the mass ratio of ethanol to NMP is 1);
then drying to remove solvent NMP, cutting the lithium iron positive plate into a circular sheet with the diameter of 12mm, and performing vacuum dehydration and drying;
the assembly method of the battery containing the lithium iron phosphate positive electrode comprises the following steps:
the lithium iron phosphate anode is placed in a glove box, the whole battery assembling process is carried out in the glove box with the water oxygen content lower than 0.1ppm, the cathode shell, the elastic sheet, the gasket, the metal, the diaphragm, the electrolyte, the anode and the anode shell are sequentially arranged in the assembling sequence from the cathode to the anode, and then the anode and the cathode are placed in a tablet press to be pressed into the CR2032 button battery.
Example 3
A preparation method of a lithium iron phosphate anode comprises the following steps:
lithium iron phosphate, trivinyl triethoxy silane and ethanol solution are mixed according to the mass ratio of 10:1:20, fully mixing, then adding carbon black (the mass is 1/8 of that of the lithium iron phosphate), and fully stirring and mixing;
adding a binder PVDF (the mass is 1/8 of that of the lithium iron phosphate) and a solvent NMP (the mass ratio of ethanol to NMP is 1);
then drying to remove solvent NMP, cutting the lithium iron positive plate into a wafer with the diameter of 12mm, and carrying out vacuum dehydration and drying;
the battery comprising the lithium iron phosphate positive electrode comprises the following assembling method:
and placing the lithium iron phosphate anode in a glove box, carrying out the whole battery assembly process in the glove box with the water oxygen content lower than 0.1ppm, sequentially arranging a cathode shell, an elastic sheet, a gasket, metal, a diaphragm, electrolyte, an anode and an anode shell according to the assembly sequence from the cathode to the anode, and then placing the cathode shell, the anode and the anode in a tablet press to press the cathode into the CR2032 button battery.
Example 4
A preparation method of a lithium iron phosphate anode comprises the following steps:
lithium iron phosphate, triaminopropyltriethoxysilane, tricyanopropyltriethoxysilane and ethanol solution are mixed according to the mass ratio of 10:1:20, then adding carbon black (the mass is 1/8 of that of the lithium iron phosphate) into the mixture, and fully stirring and mixing the mixture;
adding a binder PVDF (the mass is 1/8 of that of the lithium iron phosphate) and a solvent NMP (the mass ratio of ethanol to NMP is 1;
then drying to remove solvent NMP, cutting the lithium iron positive plate into a circular sheet with the diameter of 12mm, and performing vacuum dehydration and drying;
the assembly method of the battery containing the lithium iron phosphate positive electrode comprises the following steps:
and placing the lithium iron phosphate anode in a glove box, carrying out the whole battery assembly process in the glove box with the water oxygen content lower than 0.1ppm, sequentially arranging a cathode shell, an elastic sheet, a gasket, metal, a diaphragm, electrolyte, an anode and an anode shell according to the assembly sequence from the cathode to the anode, and then placing the cathode shell, the anode and the anode in a tablet press to press the cathode into the CR2032 button battery.
Example 5
A preparation method of a lithium iron phosphate anode comprises the following steps:
lithium iron phosphate, triaminopropyltriethoxysilane and an ethanol solution are mixed according to the mass ratio of 10:3:50, fully mixing, then adding carbon black (the mass is 1/8 of that of the lithium iron phosphate), and fully stirring and mixing;
adding a binder PVDF (the mass is 1/8 of that of the lithium iron phosphate) and a solvent NMP (the mass ratio of ethanol to NMP is 1);
then drying to remove solvent NMP, cutting the lithium iron positive plate into a wafer with the diameter of 12mm, and carrying out vacuum dehydration and drying;
the battery comprising the lithium iron phosphate positive electrode comprises the following assembling method:
and placing the lithium iron phosphate anode in a glove box, carrying out the whole battery assembly process in the glove box with the water oxygen content lower than 0.1ppm, sequentially arranging a cathode shell, an elastic sheet, a gasket, metal, a diaphragm, electrolyte, an anode and an anode shell according to the assembly sequence from the cathode to the anode, and then placing the cathode shell, the anode and the anode in a tablet press to press the cathode into the CR2032 button battery.
Example 6
A preparation method of a lithium iron phosphate anode comprises the following steps:
lithium iron phosphate, triaminopropyltriethoxysilane and an ethanol solution are mixed according to the mass ratio of 10:5:100, then adding carbon black (the mass is 1/8 of that of the lithium iron phosphate) into the mixture, and fully stirring and mixing the mixture;
adding a binder PVDF (the mass is 1/8 of that of the lithium iron phosphate) and a solvent NMP (the mass ratio of ethanol to NMP is 1);
then drying to remove solvent NMP, cutting the lithium iron positive plate into a wafer with the diameter of 12mm, and carrying out vacuum dehydration and drying;
the battery comprising the lithium iron phosphate positive electrode comprises the following assembling method:
and placing the lithium iron phosphate anode in a glove box, carrying out the whole battery assembly process in the glove box with the water oxygen content lower than 0.1ppm, sequentially arranging a cathode shell, an elastic sheet, a gasket, metal, a diaphragm, electrolyte, an anode and an anode shell according to the assembly sequence from the cathode to the anode, and then placing the cathode shell, the anode and the anode in a tablet press to press the cathode into the CR2032 button battery.
Example 7
A preparation method of a lithium iron phosphate anode comprises the following steps:
conducting carbon black, triaminopropyltriethoxysilane and an ethanol solution are mixed according to the mass ratio of 1.25:1:20, then adding lithium iron phosphate (8 times of conductive carbon black) into the mixture, and fully stirring and mixing the mixture;
adding a binder PVDF (the mass is 1/8 of that of the lithium iron phosphate) and a solvent NMP (the mass ratio of ethanol to NMP is 1;
then drying to remove solvent NMP, cutting the lithium iron positive plate into a wafer with the diameter of 12mm, and carrying out vacuum dehydration and drying;
the assembly method of the battery containing the lithium iron phosphate positive electrode comprises the following steps:
and placing the lithium iron phosphate anode in a glove box, carrying out the whole battery assembly process in the glove box with the water oxygen content lower than 0.1ppm, sequentially arranging a cathode shell, an elastic sheet, a gasket, metal, a diaphragm, electrolyte, an anode and an anode shell according to the assembly sequence from the cathode to the anode, and then placing the cathode shell, the anode and the anode in a tablet press to press the cathode into the CR2032 button battery.
Example 8
A preparation method of the lithium iron phosphate anode comprises the following steps:
fully mixing lithium iron phosphate, conductive carbon black, triaminopropyltriethoxysilane, an ethanol solution, a binder PVDF and a solvent NMP in a vortex apparatus according to a mass ratio of 10.25;
then drying to remove solvent NMP, cutting the lithium iron positive plate into a wafer with the diameter of 12mm, and carrying out vacuum dehydration and drying;
the assembly method of the battery containing the lithium iron phosphate positive electrode comprises the following steps:
and placing the lithium iron phosphate anode in a glove box, carrying out the whole battery assembly process in the glove box with the water oxygen content lower than 0.1ppm, sequentially arranging a cathode shell, an elastic sheet, a gasket, metal, a diaphragm, electrolyte, an anode and an anode shell according to the assembly sequence from the cathode to the anode, and then placing the cathode shell, the anode and the anode in a tablet press to press the cathode into the CR2032 button battery.
Comparative example 1
Compared with the preparation method of the lithium iron phosphate anode in the embodiment 1, only the triaminopropyltriethoxysilane is removed, and the other steps are the same;
the assembly method of the battery containing the lithium iron phosphate positive electrode comprises the following steps:
the lithium iron phosphate anode is placed in a glove box, the whole battery assembling process is carried out in the glove box with the water oxygen content lower than 0.1ppm, the cathode shell, the elastic sheet, the gasket, the metal, the diaphragm, the electrolyte, the anode and the anode shell are sequentially arranged in the assembling sequence from the cathode to the anode, and then the anode and the cathode are placed in a tablet press to be pressed into the CR2032 button battery.
And (4) performance testing:
the lithium iron phosphate positive electrode prepared in example 1 was subjected to SEM test as shown in fig. 2, and the lithium iron phosphate positive electrode prepared in comparative example 1 was subjected to SEM test as shown in fig. 3, and the adhesion effect of the particles after the silane coupling agent was added was compared:
as can be seen from fig. 2, the lithium iron phosphate anode linked by triaminopropyltriethoxysilane has smaller particles, and the materials are connected by liquid, so that the ion and electron conduction efficiency is improved; as can be seen from fig. 3, the lithium iron phosphate positive electrode not linked by triaminopropyltriethoxysilane has a severe granular sensation, poor interface contact between materials, and low ion electron conduction efficiency;
the battery assembled in example 1 and the battery assembled in comparative example 1 were subjected to the Land system test, and the corresponding current density and voltage test interval were selected according to the type of the metal battery, and the results are shown in fig. 4.
The above description is intended to be illustrative of the preferred embodiment of the present invention and should not be taken as limiting the invention, but rather, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Claims (10)

1. A preparation method of a lithium iron phosphate anode is characterized by comprising the following steps:
mixing and grinding lithium iron phosphate, a silane coupling agent, ethanol, carbon black, a binder and a solvent to obtain uniform slurry;
coating the slurry on a metal aluminum foil to form a smooth coating;
drying the coating on the metal aluminum foil, and removing the solvent to obtain the lithium iron phosphate anode material;
cutting the lithium iron phosphate anode material, and dehydrating and drying in vacuum to obtain the lithium iron phosphate anode.
2. The method for preparing a lithium iron phosphate positive electrode according to claim 1, wherein the ratio of lithium iron phosphate: silane coupling agent: ethanol: the mass ratio of the carbon black is 10;
the lithium iron phosphate: the mass ratio of the binder is 8;
the ethanol: the mass ratio of the solvent is 1.
3. The method for preparing a lithium iron phosphate positive electrode according to claim 1, wherein the silane coupling agent is one or more of triaminopropyltriethoxysilane, tricyanopropyltriethoxysilane and trivinyltriethoxy silane.
4. The method for preparing a lithium iron phosphate positive electrode according to claim 1, wherein the binder is PVDF;
the solvent is NMP.
5. The preparation method of the lithium iron phosphate positive electrode according to claim 1, wherein the step of mixing and grinding the lithium iron phosphate, the silane coupling agent, the ethanol, the carbon black, the binder and the solvent to obtain uniform slurry specifically comprises the following steps:
adding lithium iron phosphate, a silane coupling agent and ethanol into a vortex instrument for full mixing, and then adding conductive carbon black, a binder and a solvent into the mixture for vortex till uniform slurry is obtained.
6. The preparation method of the lithium iron phosphate positive electrode according to claim 1, wherein the step of mixing and grinding lithium iron phosphate, a silane coupling agent, ethanol, carbon black, a binder and a solvent to obtain a uniform slurry comprises the following steps:
adding conductive carbon black, a silane coupling agent and ethanol into a vortex instrument for fully mixing, and then adding lithium iron phosphate, a binder and a solvent into the mixture for vortex until uniform slurry is obtained.
7. The preparation method of the lithium iron phosphate positive electrode according to claim 1, wherein the step of mixing and grinding lithium iron phosphate, a silane coupling agent, ethanol, carbon black, a binder and a solvent to obtain a uniform slurry comprises the following steps:
and sequentially adding the lithium iron phosphate, the conductive carbon black, the silane coupling agent, the binder, the ethanol and the solvent into a vortex instrument for fully mixing until uniform slurry is obtained.
8. The method for preparing a lithium iron phosphate positive electrode according to claim 1, wherein the metal aluminum foil is 4 x 4cm;
and cutting the lithium iron phosphate anode material to obtain a circular sheet with the diameter of 12 mm.
9. A lithium iron phosphate positive electrode characterized by being produced by the method for producing a lithium iron phosphate positive electrode according to any one of claims 1 to 8.
10. A battery, comprising:
the lithium iron phosphate positive electrode of claim 9;
a negative electrode;
a diaphragm;
and (3) an electrolyte.
CN202211039617.5A 2022-08-29 2022-08-29 Lithium iron phosphate anode, preparation method and battery comprising same Pending CN115172674A (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002319405A (en) * 2001-04-23 2002-10-31 Toyota Motor Corp Lithium secondary battery
US20100167127A1 (en) * 2008-12-30 2010-07-01 Hengdian Group Dmegc Magnetic Limited Company, A Chinese Corporation Lithium iron phosphate battery electrode and method for manufacturing the same
CN101937990A (en) * 2010-09-27 2011-01-05 彩虹集团公司 Preparation method of nano lithium iron phosphate positive slurry
CN101964412A (en) * 2010-08-25 2011-02-02 宁波金和新材料股份有限公司 Lithium iron phosphate/carbon composite material with surface modified by coupling agent and preparation method thereof
CN109244458A (en) * 2018-08-31 2019-01-18 中南大学 Three-dimensional netted porous graphene/iron phosphate compound anode material of lithium and preparation method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002319405A (en) * 2001-04-23 2002-10-31 Toyota Motor Corp Lithium secondary battery
US20100167127A1 (en) * 2008-12-30 2010-07-01 Hengdian Group Dmegc Magnetic Limited Company, A Chinese Corporation Lithium iron phosphate battery electrode and method for manufacturing the same
CN101964412A (en) * 2010-08-25 2011-02-02 宁波金和新材料股份有限公司 Lithium iron phosphate/carbon composite material with surface modified by coupling agent and preparation method thereof
CN101937990A (en) * 2010-09-27 2011-01-05 彩虹集团公司 Preparation method of nano lithium iron phosphate positive slurry
CN109244458A (en) * 2018-08-31 2019-01-18 中南大学 Three-dimensional netted porous graphene/iron phosphate compound anode material of lithium and preparation method

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