CN113745460B - Positive pole piece of high-energy-density lithium ion battery, and preparation method and application thereof - Google Patents

Positive pole piece of high-energy-density lithium ion battery, and preparation method and application thereof Download PDF

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CN113745460B
CN113745460B CN202111014869.8A CN202111014869A CN113745460B CN 113745460 B CN113745460 B CN 113745460B CN 202111014869 A CN202111014869 A CN 202111014869A CN 113745460 B CN113745460 B CN 113745460B
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positive electrode
mixing
lithium
conductive
slurry
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CN113745460A (en
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莫方杰
李�昊
李若楠
请求不公布姓名
孙化雨
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Envision Power Technology Jiangsu Co Ltd
Envision Ruitai Power Technology Shanghai Co Ltd
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Envision Power Technology Jiangsu Co Ltd
Envision Ruitai Power Technology Shanghai Co Ltd
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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
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    • H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
    • H—ELECTRICITY
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    • 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
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    • H01M4/139—Processes of manufacture
    • H01M4/1391—Processes of manufacture of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
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    • 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
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    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
    • H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
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    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
    • H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
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    • 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
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    • 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 relates to a positive pole piece of a high-energy-density lithium ion battery, and a preparation method and application thereof. The raw materials of the positive electrode plate comprise a lithium supplementing material and a positive electrode material, wherein the lithium supplementing material is MO z With Li 5 FeO 4 Is a mixture of said MO z Comprises Al 2 O 3 、MgO、SiO 2 Or any one or a combination of at least two of the transition metal oxides. The lithium supplementing material and the positive electrode material are mixed to prepare the composite electrode plate, and the strong bond energy of metal M and O in the lithium supplementing material inhibits the release of oxygen element, so that the oxidation gas production of the battery is inhibited, the gas production of the battery in the storage process is reduced, and the overall stability of the battery is improved.

Description

Positive pole piece of high-energy-density lithium ion battery, and preparation method and application thereof
Technical Field
The invention relates to the field of lithium ion batteries, relates to a positive pole piece and a preparation method and application thereof, in particular to a positive pole piece of a high-energy-density lithium ion battery and a preparation method and application thereof.
Background
The most straightforward way to increase the energy density of lithium ion batteries is to use positive electrode materials with high specific capacities. Ternary layered material of positive electrode (LiNi) x Co y Mn 1-x-y O 2 ) The first coulomb efficiency of (a) was 88%, and the positive electrode lithium iron phosphate (LiFePO 4 ) The first coulombic efficiency of (2) was 98%. Lithium ion supplementing material Li widely studied at present 5 FeO 4 The (LFO) has higher first-time charging capacity (> 700 mAh/g) and lower first-time coulombic efficiency (< 10%), and good lithium ion supplementing effect. However, in LFO materials, the oxidation level of some lattice oxygen is around 4.2V to lithium potential, and therefore oxygen is released during the first charge. The released oxygen reacts with the electrolyte to break the stable CEI film between the positive electrode and the electrolyte, thereby deteriorating the stability of the battery and even causing safety problems.
How to effectively improve the energy density of the lithium ion battery and the stability of the battery in the storage cycle is an important research direction in the field of lithium ion battery anode materials.
Disclosure of Invention
In view of the problems in the prior art, the invention provides a positive electrode plate of a high-energy-density lithium ion battery, and a preparation method and application thereof.
In order to achieve the technical effects, the invention adopts the following technical scheme:
the invention aims to provide a positive electrode plate of a high-energy-density lithium ion battery, which comprises a lithium supplementing material and a positive electrode material, wherein the lithium supplementing material is MO z With Li 5 FeO 4 Is a mixture of said MO z Comprises Al 2 O 3 、MgO、SiO 2 Or any one of transition metal oxidesOr a combination of at least two, typical but non-limiting examples of which are: al (Al) 2 O 3 And a combination of transition metal oxides, mgO and transition metal oxides, a combination of transition metal oxides and transition metal oxides or Al 2 O 3 And MgO, etc.
In the invention, the positive electrode plate comprises a lithium supplementing material, and metal oxide is co-sintered or doped in the lithium supplementing material, so that the release of oxygen element is inhibited, the release of oxygen is reduced, the stability of the battery is improved, and the positive electrode material with high coulomb efficiency is compounded with the lithium supplementing material to prepare the positive electrode material with high energy density, and the energy density can reach 250-290 Wh/kg.
As a preferable technical scheme of the invention, MO in the positive electrode sheet z ：Li 5 FeO 4 The mass ratio of (0.01-0.05): (0.1-15), wherein the mass ratio may be 0.01:0.1, 0.02:0.5, 002:2, 002:5, 0.03:8, 0.04:10, 0.04:12 or 0.05:15, etc., but is not limited to the recited values, other non-recited values within the range of values are equally applicable, preferably (0.03-0.05): (2-5).
Preferably, the transition metal oxide comprises TiO 2 、SrO、ZrO 2 BaO or Y 2 O 3 Any one or a combination of at least two, typical but non-limiting examples of which are: tiO (titanium dioxide) 2 And SrO, srO and ZrO 2 Combinations of (2) ZrO 2 And BaO or BaO and Y 2 O 3 Combinations of (a) and the like.
Preferably, the positive electrode material is LiNi x Co y Mn 1-x-y O 2 Or LiFePO 4 0.5.ltoreq.x.ltoreq.0.9, 0.ltoreq.y.ltoreq.0.20, wherein the value of x may be, but is not limited to, 0.5, 0.6, 0.7, 0.8 or 0.9 etc., other non-enumerated values within the range of values are equally applicable, wherein the value of y may be, but is not limited to, 0.01, 0.02, 0.04, 0.06, 0.08, 0.10, 0.12, 0.14, 0.16, 0.18 or 0.20 etc., other non-enumerated values within the range of values are equally applicable.
Preferably, the mass ratio of the lithium supplementing material to the positive electrode material is (0.1-10): (90-99), wherein the mass ratio may be 0.1: 90. 2: 92. 4: 94. 6: 96. 8:98 or 10:99, etc., but not limited to the recited values, other non-recited values within the range are equally applicable, preferably (1-2): (95-99).
As a preferable technical scheme of the invention, the LiNi x Co y Mn 1-x-y O 2 In the form of a secondary sphere or a single crystal.
Preferably, the LiNi x Co y Mn 1-x-y O 2 The D50 particle size of the secondary sphere form is 9 to 25. Mu.m, and the D50 particle size may be 9 μm, 11 μm, 13 μm, 15 μm, 17 μm, 19 μm, 21 μm, 23 μm, 25 μm or the like, but is not limited to the recited values, and other values not recited in the range of the recited values are equally applicable.
Preferably, the LiNi x Co y Mn 1-x-y O 2 The D50 particle size of the single crystal form is 1.5-6 μm, preferably, the LiNi x Co y Mn 1-x-y O 2 The D50 particle size of the single crystal form may be 1.5 μm, 2 μm, 2.5 μm, 3 μm, 3.5 μm, 4 μm, 4.5 μm, 5 μm, 5.5 μm, or 6 μm, etc., but is not limited to the recited values, and other non-recited values within the range of values are equally applicable.
As a preferred embodiment of the present invention, the LiFePO 4 The material of (2) is spherical lithium iron phosphate or nano lithium iron phosphate.
Preferably, the D50 particle size of the spherical lithium iron phosphate is 5 to 15. Mu.m, and the D50 particle size may be 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm or 15 μm, etc., but is not limited to the recited values, and other non-recited values within the range of the values are equally applicable.
Preferably, the D50 particle size of the nano lithium iron phosphate is 0.3 to 2.4. Mu.m, and the D50 particle size may be 0.3. Mu.m, 0.5. Mu.m, 0.7. Mu.m, 0.9. Mu.m, 1.1. Mu.m, 1.3. Mu.m, 1.5. Mu.m, 1.7. Mu.m, 1.9. Mu.m, 2.1. Mu.m, 2.3. Mu.m, or 2.4. Mu.m, etc., but is not limited to the recited values, and other non-recited values within the range of the values are equally applicable.
As a preferred technical scheme of the invention, the positive electrode plate further comprises a positive electrode material, a conductive agent, a solvent and a binder, preferably, the conductive agent is conductive carbon black and/or conductive carbon tubes, preferably, a combination of the conductive carbon black and the conductive carbon tubes.
Preferably, the solvent is azamethylpyrrolidone.
Preferably, the binder is polyvinylidene fluoride.
As a preferable technical scheme of the invention, the positive plate comprises the following raw materials in mass ratio: lithium supplementing material: positive electrode material: conductive agent: solvent: the binder is (0.1-10): (90-99): (1.4-1.6): (38-42): (0.8-1.2), wherein the mass ratio may be 0.1:90:1.4:38:0.8, 2:92:1.5:39:0.9, 4:94:1.6:40: 1.6: 96:1.5:41:1.2, 8:98:1.5:42:1.2 or 10:99:1.6:42:1.2, etc., but not limited to the recited values, other non-recited values within the range of values are equally applicable, preferably (1-2): (95-99): (1.45-1.55): (39 to 41): (0.9 to 1.1), more preferably 2:99:1.5:40:1.
preferably, the mass ratio of the conductive carbon black to the conductive carbon tube in the conductive agent is (1-3): 1, wherein the mass ratio can be 1:1. 2:1 or 3:1, etc., but are not limited to the recited values, and other non-recited values within the range of values are equally applicable.
The second object of the present invention is to provide a method for preparing the positive electrode sheet according to the first aspect, the method comprising the steps of:
(1) Mixing a lithium supplementing material and a positive electrode material to prepare mixed active material powder;
(2) Other raw materials of the positive electrode plate are mixed to prepare conductive slurry;
(3) Mixing the active material powder with the conductive slurry to prepare anode slurry;
(4) And uniformly coating the positive electrode slurry to prepare a positive electrode plate.
According to the invention, the lithium supplementing material and the positive electrode material are mixed to prepare the composite electrode slice, and the prepared electrode slice has high energy density.
As a preferable technical scheme of the invention, other raw materials of the positive electrode plate in the step (2) comprise a conductive agent, a solvent and a binder.
Preferably, the stirring rate of the mixing in the steps (1) - (3) is 800-2000 rpm independently, and the stirring rate may be 800rpm, 900rpm, 1000rpm, 1100rpm, 1200rpm, 1300rpm, 1400rpm, 1500rpm, 1600rpm, 1700rpm, 1800rpm, 1900rpm or 2000rpm, etc., but is not limited to the recited values, and other non-recited values within the range of the values are equally applicable.
Preferably, the mixing time of steps (1) - (3) is 1.5-2.5 h independently, and the time may be 1.5h, 1,6h, 1.7h, 1.8h, 1.9h, 2h, 2.1h, 2.2h, 2.3h, 2.4h or 2.5h, and the like, but is not limited to the recited values, and other non-recited values within the range of values are equally applicable.
Preferably, the coating of step (4) is followed by a stationary drying.
Preferably, the temperature of the standing and drying in the step (4) is 100 to 150 ℃, and the temperature may be 100 ℃, 105 ℃, 110 ℃, 115 ℃, 120 ℃, 125 ℃, 130 ℃, 135 ℃, 140 ℃, 145 ℃, 150 ℃, or the like, but is not limited to the values listed, and other values not listed in the range of the values are equally applicable.
Preferably, the time of standing and drying in the step (4) is 15-25 min, and the time may be 15min, 16min, 17min, 18min, 19min, 20min, 21min, 22min, 23min, 24min or 25min, etc., but is not limited to the recited values, and other non-recited values within the range of the values are equally applicable.
Preferably, the standing and drying is followed by rolling and cutting treatment.
Preferably, the rolling pressure in the step (4) is 15 to 25MPa, and the rolling pressure may be 15MPa, 16MPa, 17MPa, 18MPa, 19MPa, 20MPa, 21MPa, 22MPa, 23MPa, 24MPa, 25MPa, or the like, but is not limited to the values listed, and other values not listed in the range are equally applicable.
As a preferable technical scheme of the invention, the preparation method of the lithium supplementing material comprises the steps of mixing MO z Or MO (metal oxide semiconductor) z By blending or co-sintering the precursor of (c) to introduce Li 5 FeO 4 。
Preferably, the MO z The precursor of (2) is hydroxide or acetate of the corresponding metal.
Preferably, the blending means includes dry mixing and wet mixing,
preferably, the stirring rate of the mixture is 800-2200 r/min, wherein the stirring rate can be 800r/min, 1000r/min, 1200r/min, 1400r/min, 1600r/min, 1800r/min or 2000r/min, etc., but is not limited to the recited values, and other non-recited values within the range of values are equally applicable.
Preferably, the stirring time of the mixing is 30-240 min, wherein the time can be 30min, 60min, 90min, 120min, 150min, 180min, 210min or 240min, etc., but is not limited to the recited values, and other non-recited values within the range of values are equally applicable.
The temperature of the co-sintering is preferably 650 to 800 ℃, and the temperature may be 650 to 670 ℃, 690 ℃, 710 ℃, 730 ℃, 750 ℃, 770 ℃, 790 ℃, or 800 ℃, etc., but is not limited to the values listed, and other values not listed in the range are applicable, and more preferably 700 to 750 ℃.
Preferably, the time for the co-sintering is 16 to 40 hours, and the time may be 16 hours, 20 hours, 25 hours, 30 hours, 35 hours, 40 hours, or the like, but is not limited to the recited values, and other non-recited values within the range are equally applicable, and more preferably 25 to 32 hours.
It is a third object of the present invention to provide an application of the positive electrode sheet according to the first aspect, wherein the positive electrode sheet is applied to the field of lithium ion batteries.
Compared with the prior art, the invention has at least the following beneficial effects:
the invention adopts the high coulomb efficiency anode material and the lithium supplementing material to prepare the anode material with high energy density, and the energy density can reach more than 250 Wh/kg. The lithium supplementing material is co-sintered or doped with metal oxide, so that the release of oxygen element is inhibited, the release of oxygen is reduced, the gas yield in the storage process of the battery is reduced, and the gas yield can be reduced to below 5% in 56 days. The stability of the battery is improved.
Drawings
FIG. 1 is a graph of gas production in example 1 and comparative example 1 as a function of days of storage.
Detailed Description
The technical scheme of the invention is further described below by the specific embodiments with reference to the accompanying drawings. The following examples are merely illustrative of the present invention and are not intended to represent or limit the scope of the invention as defined in the claims.
In the prior art, a technical proposal provides a lithium ion battery, the anode material of the lithium ion battery is selected from LiNi x M 1-x O 2 Wherein M is selected from one or a combination of at least two of Co, mn, al, mg, ti, zr or B, the additive of the electrolyte comprises a sulfone compound, the sulfone compound in the electrolyte reacts with the surface of the high-nickel positive electrode material to finally form a protective layer, and the formed protective layer can reduce the catalytic decomposition of transition metal ions on the surface of the positive electrode material to the electrolyte, so that the gas yield of the lithium ion battery in high-temperature storage is reduced, and the lithium ion battery has good cycle performance and high-temperature storage performance. Although lithium ion batteries have good cycle performance and high temperature storage performance under this method, no solution of LFO materials and LFO materials to inhibit oxygen release is mentioned.
The other technical scheme provides a lithium ion positive electrode material lithium supplementing additive and a preparation method thereof, and the lithium ion positive electrode material lithium supplementing additive comprises two coating layers, wherein the first coating layer is a carbon coating layer, the second coating layer is a transition metal oxide coating layer, and the double coating layers can realize the exertion of the lithium supplementing performance of the LFO material and prolong the service life of a lithium ion battery. This is because Li 5 FeO 4 Activity of particle surface O 2- Easy to be connected with airCO in (b) 2 And H 2 O reacts to form CO 3 2- And OH (OH) - And form Li on the surface of the material 2 CO 3 And LiOH, so that a layer of transition metal oxide is coated on the surface of LFO to form stable Li on the surface 5 Fe 1-x M x O 4 The solid solution interface reduces the direct contact between the material and the outside air, and effectively isolates the moisture and the carbon dioxide. Although the technical scheme isolates the problem of contact between the LFO and the air, the problem of inhibiting oxygen release in the LFO is not solved.
Another technical scheme provides a lithium ion multi-element positive electrode material with high residual alkali and a preparation method thereof. The raw materials comprise Li a Ni x Co y Mn 1-x-y A z O 2 The positive electrode material with high residual alkali is obtained by sintering any one or the combination of at least two of the oxides with A of Cr, la, ce, zr, mg, al, W, V, be, Y, mo, tb, ho or Tm, so that the cation mixing and discharging phenomenon is reduced, the structure is stabilized, the overcharge safety performance of the steel shell battery can be improved, and the electrochemical performance of the steel shell battery is improved. The technical scheme provides a sintering mode, and the mixed discharge phenomenon of the sintering cations is reduced, so that the ternary positive electrode material structure is more stable.
However, there is no mention in the prior art of how to effectively increase the energy density of a lithium ion battery and to increase the stability of the battery during storage cycles. The technical problem is an important research direction in the field of lithium ion battery anode materials.
In order to solve at least the technical problems, the invention provides a technical scheme of a positive pole piece of a high-energy-density lithium ion battery. The positive electrode plate comprises a lithium supplementing material and a positive electrode material. By co-sintering or doping metal oxide in the lithium supplementing material, the release of oxygen element can be inhibited, so that the release of oxygen is reduced, and the stability of the battery is improved.
Example 1
The positive electrode plate is prepared by the following steps:
(1) According to Al 2 O 3 -Li 5 FeO 4 Is in the form of a mixture with a secondary sphere 0.8 Co 0.1 Mn 0.1 O 2 The mass ratio is 2:99 preparing raw materials, and stirring for 2h at a stirring rate of 1400rmp to obtain active substance-doped powder, wherein the Al 2 O 3 With Li 5 FeO 4 The mass ratio of (2) is 0.05:2;
(2) The mass ratio is 1:0.5:40: super P, CNT, NMP, PVDF of 1 was stirred for 2 hours by a stirring rate of 1400rmp to prepare a conductive paste;
(3) The mixed active material powder and the conductive slurry are stirred for 2 hours at a stirring rate of 1400rmp to prepare anode slurry;
(4) And uniformly coating the anode slurry on an aluminum foil, standing and drying for 20 minutes at 120 ℃, and rolling and cutting at 15MPa to prepare the anode electrode slice.
The preparation method of the lithium supplementing material in the step (1) comprises the following steps:
al is added with 2 O 3 Li is introduced by dry mixing and stirring and blending under stirring at a stirring rate of 800r/min for 240min 5 FeO 4 。
Example 2
The positive electrode plate is prepared by the following steps:
(1) According to MgO-Li 5 FeO 4 Is a mixture of (a) and single crystal form of LiNi 0.8 Co 0.1 Mn 0.1 O 2 The mass ratio is 0.1:90, preparing raw materials, and then stirring for 2.5 hours at a stirring rate of 800rmp to prepare active material-doped powder; the MgO and Li 5 FeO 4 The mass ratio of (2) is 0.01:0.1;
(2) The mass ratio is 1:0.5:38: super P of 0.8, CNT, NMP, PVDF was stirred for 2.5 hours by a stirring rate of 800rmp to prepare a conductive paste;
(3) The mixed active material powder and the conductive slurry are stirred for 2.5 hours at a stirring rate of 800rmp to prepare positive electrode slurry;
(4) And uniformly coating the anode slurry on an aluminum foil, standing and drying for 25 minutes at 100 ℃, and rolling and cutting at 25MPa to prepare the anode electrode slice.
The preparation method of the lithium supplementing material in the step (1) comprises the following steps:
MgO is stirred for 30min at the stirring speed of 2200r/min, and Li is introduced by wet mixing and stirring 5 FeO 4 。
Example 3
The positive electrode plate is prepared by the following steps:
(1) According to SrO-Li 5 FeO 4 Is in the form of a mixture with a secondary sphere 0.8 Co 0.1 Mn 0.1 O 2 The mass ratio is 10:99 preparing raw materials, and stirring for 2.3h at a stirring rate of 1100rmp to obtain mixed active substance powder, wherein SrO and Li are 5 FeO 4 The mass ratio of (2) is 0.05:15;
(2) The mass ratio is 1:05:42: super P, CNT, NMP, PVDF of 1.2 was stirred for 2.3 hours by a stirring rate of 1100rmp to prepare a conductive paste;
(3) The mixed active material powder and the conductive slurry are stirred for 2.3 hours at the stirring rate of 1100rmp to prepare positive electrode slurry;
(4) And uniformly coating the anode slurry on an aluminum foil, standing and drying for 23 minutes at 110 ℃, and rolling and cutting at 20MPa to prepare the anode electrode slice.
The preparation method of the lithium supplementing material in the step (1) comprises the following steps:
sintering SrO at 650 deg.c for 40 hr and introducing Li 5 FeO 4 。
Example 4
The positive electrode plate is prepared by the following steps:
(1) According to ZrO 2 -Li 5 FeO 4 Is mixed with spherical LiFePO 4 The mass ratio is 1:95 preparing raw materials, and then stirring for 1.5 hours at a stirring rate of 2000rmp to prepare active material-doped powder; the SrO and Li 5 FeO 4 Is 0.03:2 by mass
(2) The mass ratio is 1:0.5:39: super P of 0.9, CNT, NMP, PVDF was stirred for 1.5 hours by a stirring rate of 2000rmp to prepare a conductive paste;
(3) The mixed active material powder and the conductive slurry are stirred for 1.5 hours at a stirring rate of 2000rmp to prepare positive electrode slurry;
(4) And uniformly coating the anode slurry on an aluminum foil, standing and drying for 17 minutes at 130 ℃, and rolling and cutting under 17MPa to prepare the anode electrode slice.
The preparation method of the lithium supplementing material in the step (1) comprises the following steps:
sintering SrO at 800 deg.c for 16 hr and introducing Li 5 FeO 4 。
Example 5
The positive electrode plate is prepared by the following steps:
(1) According to Y 2 O 3 -Li 5 FeO 4 Is mixed with nano LiFePO 4 The mass ratio is 2:97, and then stirred for 1.7h at a stirring rate of 1700rmp to prepare a blended active material powder, Y 2 O 3 With Li 5 FeO 4 The mass ratio of (2) is 0.05:5.
(2) The mass ratio is 1:0.5:41: super P, CNT, NMP, PVDF of 1.1 was stirred for 1.7 hours by a stirring rate of 1700rmp to prepare an electroconductive slurry;
(3) The mixed active material powder and the conductive slurry are stirred for 1.7 hours at the stirring rate of 1700rmp to prepare anode slurry;
(4) The positive electrode slurry is uniformly coated on an aluminum foil, and after standing and drying for 15 minutes at 150 ℃, the positive electrode plate is prepared by rolling and cutting under 22 MPa.
The preparation method of the lithium supplementing material in the step (1) comprises the following steps:
sintering SrO at 700 deg.c for 32 hr and introducing Li 5 FeO 4 。
Example 6
Al is added with 2 O 3 LiNi in form of secondary sphere 0.8 Co 0.1 Mn 0.1 O 2 The mass ratio of (2) was changed to 0.01:16, and the other was the same as in example 1.
Example 7
Al is added with 2 O 3 LiNi in form of secondary sphere 0.8 Co 0.1 Mn 0.1 O 2 Is of the quality of (1)The ratio was changed to 0.06:0.09, and the other was the same as in example 1.
Example 8
Al is added with 2 O 3 -Li 5 FeO 4 Is in the form of a mixture with a secondary sphere 0.8 Co 0.1 Mn 0.1 O 2 The mass ratio of (2) was changed to 11:80, and the other was the same as in example 1.
Example 9
Al is added with 2 O 3 -Li 5 FeO 4 Is in the form of a mixture with a secondary sphere 0.8 Co 0.1 Mn 0.1 O 2 The mass ratio of (2) is changed to 0.09:110, all other things being equal to those of example 1.
Example 10
The mass ratio of Super P to CNT, NMP, PVDF is changed to 1:0.5:37:1.3, the remainder being the same as in example 1.
Example 11
The mass ratio of Super P to CNT, NMP, PVDF is changed to 1:0.5:43:0.7, and the other components are the same as in example 1.
Example 12
Al in the lithium supplementing material 2 O 3 Replaced by TiO 2 Thereafter, the procedure was the same as in example 1.
Example 13
Al in the lithium supplementing material 2 O 3 Replaced by SiO 2 Thereafter, the procedure was the same as in example 1.
Example 14
Al in the lithium supplementing material 2 O 3 The procedure of example 1 was repeated except that BaO was used instead.
Comparative example 1
This comparative example contains no Al except for the lithium supplementing material 2 O 3 Except for this, the other conditions were the same as in example 1.
From fig. 1, it can be seen that the gas yield of example 1 is significantly reduced as compared with comparative example 1.
Comparative example 2
Comparative example except for the addition of Al to the lithium supplementing material 2 O 3 Replaced by other than CaOHe was the same as in example 1.
Comparative example 3
This comparative example was the same as example 1, except that no lithium supplementing material was added.
The positive electrode sheets of examples 1 to 14 and comparative examples 1 to 3 were tested for gas production, and the results are shown in Table 1.
The method for testing the gas production of the positive electrode plate comprises the following steps:
the positive electrode sheets prepared in examples 1 to 14 and comparative examples 1 to 3 were assembled into a 1Ah pouch battery, which was charged to a voltage of 4.3V at 3.3C magnification at room temperature after the formation and aging process, and the initial volume V of the battery was recorded using a drainage method 0 The cells were then stored in a 60 ℃ oven, removed from the oven every 7 days, allowed to stand to room temperature, the volume of the cells tested, and charged to a voltage of 4.25V at a rate of 0.33C. The volume change of the battery corresponds to the gas yield of the battery cell.
The energy density is calculated by multiplying the gram capacity by the median discharge voltage of the battery.
TABLE 1
Figure BDA0003240044080000131
Figure BDA0003240044080000141
From the above results, it can be seen that examples 1, 2, 4, 5, 12, 13 and 14 changed the mixed oxide, and the stored gas yield was significantly reduced as compared with comparative examples 1 and 2, and the energy density was increased as compared with comparative example 3. Examples 3, 6 and 8 increased the proportion of lithium supplement additive, which significantly increased the energy density and lower the gas yield compared to comparative example 1. Examples 7 and 9 have improved energy density and reduced stored gas production compared to comparative example 3. Examples 10 and 11, which adjust the PVDF amount, have energy density and stored gas production superior to those of comparative example 1, show that the improvement scheme can be adapted to various PVDF formulation ratios.
The applicant states that the detailed structural features of the present invention are described by the above embodiments, but the present invention is not limited to the above detailed structural features, i.e. it does not mean that the present invention must be implemented depending on the above detailed structural features. It should be apparent to those skilled in the art that any modifications of the present invention, equivalent substitutions of selected components of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope of the present invention and the scope of the disclosure.

Claims (17)

1. The positive electrode plate of the lithium ion battery with high energy density is characterized in that the energy density of the lithium ion battery is more than 250Wh/kg, the positive electrode plate comprises a lithium supplementing material and a positive electrode material, and the lithium supplementing material is MO z With Li 5 FeO 4 Is a mixture of said MO z Comprises Al 2 O 3 、MgO、SiO 2 Or a transition metal oxide, or a combination of any one or at least two of the foregoing, the MO z With Li 5 FeO 4 The mass ratio of (0.03-0.05): (2-5), the transition metal oxide comprising TiO 2 、SrO、ZrO 2 Or Y 2 O 3 Any one or a combination of at least two of the following;
the general formula of the positive electrode material is LiNi x Co y Mn 1-x-y O 2 Or LiFePO 4 Wherein x is more than or equal to 0.5 and less than or equal to 0.9, y is more than or equal to 0 and less than or equal to 0.20, the positive electrode plate further comprises a conductive agent, a solvent and a binder, wherein the lithium supplementing material is as follows: positive electrode material: conductive agent: solvent: the mass ratio of the binder is (1-2): (95-99): (1.4-1.6): (38-42): (0.8-1.2);
the positive electrode plate of the lithium ion battery is prepared by the following preparation method, wherein the preparation method comprises the following steps:
step 1, mixing and stirring a lithium supplementing material and a positive electrode material to obtain mixed active material powder;
step 2, mixing and stirring the conductive agent, the solvent and the binder to obtain conductive slurry;
step 3, mixing the active material powder with the conductive slurry to obtain positive electrode slurry;
step 4, uniformly coating the positive electrode slurry on a current collector to obtain a positive electrode plate;
the preparation method of the lithium supplementing material comprises the steps of mixing MO z Incorporation of Li by blending 5 FeO 4 The mixing mode comprises dry mixing and wet mixing, wherein the stirring rates of the dry mixing and the wet mixing are 800-2200 r/min, and the stirring time of the dry mixing and the wet mixing is 30-240 min.
2. The positive electrode tab of claim 1 wherein the LiNi x Co y Mn 1-x-y O 2 In the form of a secondary sphere or a single crystal.
3. The positive electrode sheet according to claim 2, wherein the LiNi x Co y Mn 1-x-y O 2 The secondary sphere form of (2) has a D50 particle size of 9 to 25 μm.
4. The positive electrode sheet according to claim 2, wherein the LiNi x Co y Mn 1-x-y O 2 The D50 particle size of the single crystal form is 1.5-6 mu m.
5. The positive electrode sheet according to claim 1, wherein the LiFePO 4 The material of (2) is spherical lithium iron phosphate or nano lithium iron phosphate.
6. The positive electrode sheet according to claim 5, wherein the spherical lithium iron phosphate has a D50 particle diameter of 5 to 15 μm.
7. The positive electrode sheet according to claim 5, wherein the D50 particle size of the nano lithium iron phosphate is 0.3 to 2.4 μm.
8. The positive electrode sheet according to claim 1, wherein the conductive agent is conductive carbon black and/or conductive carbon tube.
9. The positive electrode sheet of claim 8, wherein the conductive agent is a combination of conductive carbon black and conductive carbon tube.
10. The positive electrode sheet according to claim 1, wherein the lithium supplementing material: positive electrode material: conductive agent: solvent: the mass ratio of the binder is (1-2): (95-99): (1.45-1.55): (39 to 41): (0.9-1.1).
11. The positive electrode sheet according to claim 9, wherein the mass ratio of the conductive carbon black to the conductive carbon tube in the conductive agent is (1-3): 1.
12. A method for preparing a positive electrode sheet according to any one of claims 1 to 11, comprising:
step 1, mixing and stirring a lithium supplementing material and a positive electrode material to obtain mixed active material powder;
step 2, mixing and stirring the conductive agent, the solvent and the binder to obtain conductive slurry;
step 3, mixing the active material powder with the conductive slurry to obtain positive electrode slurry;
and 4, uniformly coating the positive electrode slurry on a current collector to obtain a positive electrode plate.
13. The method according to claim 12, wherein the mixing and stirring rates in steps 1 to 3 are each independently 800 to 2000rpm.
14. The method according to claim 12, wherein the mixing and stirring time in steps 1 to 3 is 1.5 to 2.5 hours, respectively.
15. The method of claim 12, wherein the step 4 is performed with a stationary drying after the coating.
16. The method according to claim 15, wherein the temperature of the stationary drying is 100 to 150 ℃.
17. The method according to claim 15, wherein the time for the stationary drying is 15 to 25 minutes.
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001015115A (en) * 1999-06-29 2001-01-19 Kyocera Corp Lithium secondary battery
CN110867584A (en) * 2019-11-04 2020-03-06 宁德新能源科技有限公司 Lithium supplement material and positive electrode comprising same
CN111816822A (en) * 2020-06-18 2020-10-23 中国科学院化学研究所 Functional lithium-supplementing diaphragm and preparation method thereof

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110212167A (en) * 2018-02-28 2019-09-06 中信国安盟固利动力科技有限公司 A kind of positive additive and preparation method thereof by metal oxide cladding
CN110518297A (en) * 2018-05-22 2019-11-29 湖北猛狮新能源科技有限公司 Lithium ion cell positive mends lithium material Li5FeO4Preparation method and application
CN109659519B (en) * 2018-11-30 2020-09-08 淮安新能源材料技术研究院 TiO2Preparation method of nanofiber-coated lithium ion battery ternary cathode material and product
JP2020123460A (en) * 2019-01-29 2020-08-13 株式会社Ｇｓユアサ Pre-doping material, positive electrode including pre-doping material, and method for producing non-aqueous electrolyte secondary battery including positive electrode thereof, and method for producing metal oxide
CN112490415B (en) * 2019-09-12 2022-06-28 巴斯夫杉杉电池材料有限公司 Lithium ion anode material lithium supplement additive and preparation method thereof

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001015115A (en) * 1999-06-29 2001-01-19 Kyocera Corp Lithium secondary battery
CN110867584A (en) * 2019-11-04 2020-03-06 宁德新能源科技有限公司 Lithium supplement material and positive electrode comprising same
CN111816822A (en) * 2020-06-18 2020-10-23 中国科学院化学研究所 Functional lithium-supplementing diaphragm and preparation method thereof

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