CN107834067A

CN107834067A - A kind of Cu, Er codope combination electrode material and preparation method thereof

Info

Publication number: CN107834067A
Application number: CN201710587877.9A
Authority: CN
Inventors: 郑观情
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-07-18
Filing date: 2017-07-18
Publication date: 2018-03-23

Abstract

The invention discloses a kind of Cu, the preparation method of Er codope combination electrode materials.Using lithium carbonate, ferric oxalate, ammonium dihydrogen phosphate and rare earth Er powder and Cu powder as raw material, Li is prepared_1‑xEr_xFe_1‑yCu_yPO₄Combination electrode material.First raw material is mixed by atomic ratio dispensing, then it is become micron powder by mechanical ball mill and is uniformly dispersed, Technology for Heating Processing is then carried out under protective gas atmosphere, it is become uniform alloy powder.The electrode material circulation and volumetric properties that the technique is simple, prepares are good.

Description

A kind of Cu, Er codope combination electrode material and preparation method thereof

Technical field

The present invention relates to a kind of li-ion electrode materials and its preparation technology, more particularly to a kind of rare earth doped Er's and Cu Li-ion electrode materials and preparation method thereof, belong to battery electrode material field.

Background technology

With the development of global portable power source, lithium ion battery is widely used.Lithium ion battery have volume, Weight energy than it is high, voltage is high, self-discharge rate is low, have extended cycle life, power density is high the advantages that.Lithium ion battery electrode material LiCoO₂Theoretical specific capacity is 274mAh/G, and actual specific capacity is between 130-140mAh/G, and cobalt is strategic materials, valency Lattice are expensive and have larger toxicity.Therefore in recent years, the researcher of countries in the world is being directed to new type lithium ion battery just always The research and development of pole material, to current, up to tens of kinds of the lithium ion cell positive filtered out, but really there is potential commercialization Application prospect or be already present in the market positive electrode it is really very few.Such as lithium manganate having spinel structure LiMn₂O₄, its into This is relatively low, is easier to prepare, security performance is also relatively good, but capacity is relatively low, theoretical capacity 148mAh/G, actual capacity In 100-120mAh/G, and the material capacity circulation holding capacity it is bad, under high temperature capacity attenuation quickly, Mn3+ John- Teller effects and dissolving in the electrolyte annoying researcher for a long time.The LiNiO of layer structure₂And LiMnO₂Though So there are larger theoretical specific capacity, respectively 275mAh/G and 285mAh/G, but they prepare extremely difficult, heat endurance Difference, cyclicity is very poor, and capacity attenuation is quickly.And LiFePO₄For the polyanionic structure phosphate material of representative, because it is prominent The security that goes out, overlength cycle life, wide electrochemical window, it is inexpensive the features such as receive extensive concern.LiFePO₄With slightly The hexagonal closs packing arrangement architecture of micro- distortion, belong to rhombic system, space group Pnma.In the a-c planes where lithium atom In, include PO₄Tetrahedron, which limits the mobile space of lithium ion, causes lithium ion mobility speed and electronic conductivity Relatively low, this is LiFePO₄The inherent defect of material, this shortcoming constrain LiFePO always₄Lithium battery is further applied.

In order to improve LiFePO₄Performance, rare earth element is often added in actual fabrication process, rare earth element is metal " vitamin " of material, there play the role of to the performance for improving metal material to be special.Rare earth element can instead of Li position, very Good is dissolved into olivine structural.But rare earth element is only added, to LiFePO₄Conductance performance improvement unobvious, LiFePO₄The application of electrode material cannot be lifted further.

The content of the invention

The present invention prepares a kind of Li by ball-milling technology and high temperature solid-state method_1-xEr_xFe_1-yCu_yPO₄Combination electrode material, lead to Cross addition rare earth Er powder and Cu powder during tradition is using ball-milling technology and high temperature solid-state method and be doped Er and Cu atoms, make Standby Li_1-xEr_xFe_1-yCu_yPO₄Combination electrode material, make up LiFePO₄Deficiency, improve LiFePO₄Conduction and charge and discharge it is electrical Energy.The method technique is simple, and presoma mixability is good, and production cost is low.The preparation technology of the electrode material powder includes Following steps：

(1) with Li₂CO₃As lithium source, with FeC₂O₄・2H₂O is as source of iron, NH₄H₂PO₄As source of phosphoric acid, and Er powder and Cu powder As the raw material of foreign atom, according to Li_1-xEr_xFe_1-yCu_yPO₄（0.02≤x≤0.1, 0. 05≤y≤0.2）Atomic ratio Dispensing, then obtain slurry with certain steel ball and ball-milling medium progress mechanical ball mill 10-15 hours；

(2) by step, (1) resulting slurry takes out ball grinder, slurry is dried processing, and dry forerunner is obtained after processing Body powder；

(3) under atmosphere of inert gases protection under conditions of 500-600 DEG C, the precursor powder obtained by step (2) is subjected to heat Handle 6-8h；

(4) temperature is increased to 700-800 DEG C again, constant temperature heat treatment 10-15h；

(5) products therefrom naturally cools to room temperature under atmosphere of inert gases protection, that is, obtains Li_1-xEr_xFe_1-yCu_yPO₄Compound electric Pole material powder.

The preparation technology of described electrode material powder, step (1) in, ball-milling medium is absolute alcohol or acetone.Institute The preparation technology for the electrode material powder stated, step (2) in, the drying process of the presoma is spray drying treatment method. The preparation technology of described electrode material powder, step (3) in, described inert gas be nitrogen, argon gas or both it is mixed Close gas.The preparation technology of described electrode material powder, step (5) in, described inert gas be nitrogen, argon gas or Both mixed gas.

Embodiment one：

With Li₂CO₃As lithium source, with FeC₂O₄・2H₂O is as source of iron, NH₄H₂PO₄Make as source of phosphoric acid, and Er powder and Cu powder For doped raw material, according to Li_0.98Er_0.02Fe_0.95Cu_0.05PO₄Atom ratio dispensing 5g mixture, the mixture prepared is former Material poured into together in ball grinder after tentatively mixing, then toward adding appropriate steel ball and absolute alcohol ball-milling medium in ball grinder, Then cover ball grinder lid and tighten screw, then put it into planetary ball mill and carry out ball milling 10 hours, remove ball milling After tank stands a period of time, ball grinder is opened, alloy powder slurry in ball grinder is taken out and carries out being spray-dried to obtain precursor End, then powder carried out under the protective condition of nitrogen to be heated at high temperature to 500 DEG C, constant temperature 6 hours, temperature is then raised to 700 DEG C, constant temperature 10 hours, products therefrom naturally cools to room temperature under inert atmosphere protection, collects powder and produces product.

Embodiment two：

With Li₂CO₃As lithium source, with FeC₂O₄・2H₂O is as source of iron, NH₄H₂PO₄Make as source of phosphoric acid, and Er powder and Cu powder For doped raw material, according to Li_0.95Er_0.05Fe_0.9Cu_0.1PO₄Atom ratio dispensing 20g mixture, the mixture prepared is former Material poured into together in ball grinder after tentatively mixing, then toward adding appropriate steel ball and absolute alcohol ball-milling medium in ball grinder, Then cover ball grinder lid and tighten screw, then put it into planetary ball mill and carry out ball milling 12 hours, remove ball milling After tank stands a period of time, ball grinder is opened, alloy powder slurry in ball grinder is taken out and carries out being spray-dried to obtain precursor End, then powder carried out under the protective condition of nitrogen to be heated at high temperature to 550 DEG C, constant temperature 7 hours, temperature is then raised to 750 DEG C, constant temperature 12 hours, products therefrom naturally cools to room temperature under inert atmosphere protection, collects powder and produces product.

Embodiment three：

With Li₂CO₃As lithium source, with FeC₂O₄・2H₂O is as source of iron, NH₄H₂PO₄Make as source of phosphoric acid, and Er powder and Cu powder For doped raw material, according to Li_0.9Er_0.1Fe_0.8Cu_0.2PO₄Atom ratio dispensing 50g mixture, the mixture prepared is former Material poured into together in ball grinder after tentatively mixing, then toward adding appropriate steel ball and absolute alcohol ball-milling medium in ball grinder, Then cover ball grinder lid and tighten screw, then put it into planetary ball mill and carry out ball milling 15 hours, remove ball milling After tank stands a period of time, ball grinder is opened, alloy powder slurry in ball grinder is taken out and carries out being spray-dried to obtain precursor End, then precursor powder is fitted into the quartz glass tube of an end closure, inside full of appropriate nitrogen, then melted with thermal-flame The quartzy tube opening other end makes its sealing, will verify air-tightness in the quartz glass tube input water of sealing, if bubble-free, can recognize Its fixed sealing is good, will carry out being heated at high temperature to 600 DEG C under protective condition of the powder in nitrogen, constant temperature 8 hours, Ran Housheng For high-temperature to 800 DEG C, constant temperature 15 hours, products therefrom naturally cools to room temperature under inert atmosphere protection, collects powder and produces Product.

Claims

1. the preparation method of a kind of Cu, Er codope combination electrode material, it is characterised in that the preparation method is entered as follows OK：

(1) with Li₂CO₃As lithium source, with FeC₂O₄・2H₂O is as source of iron, NH₄H₂PO₄Make as source of phosphoric acid, and Er powder and Cu powder For the raw material of foreign atom, according to Li_1-xEr_xFe_1-yCu_yPO₄（0.02≤x≤0.1, 0. 05≤y≤0.2）Atomic ratio match somebody with somebody Material, then obtain slurry with certain steel ball and ball-milling medium progress mechanical ball mill 10-15 hours；

2. a kind of Cu as claimed in claim 1, the preparation method of Er codope combination electrode materials, it is characterised in that in step Suddenly (1) in, ball-milling medium is absolute alcohol or acetone.

3. a kind of Cu as claimed in claim 1, the preparation method of Er codope combination electrode materials, it is characterised in that in step Suddenly (2) in, the drying process of the presoma is spray drying treatment method.

4. a kind of Cu as claimed in claim 1, the preparation method of Er codope combination electrode materials, it is characterised in that in step Suddenly (3) in, described inert gas is the mixed gas of nitrogen, argon gas or both.

5. a kind of Cu as claimed in claim 1, the preparation method of Er codope combination electrode materials, it is characterised in that in step Suddenly (5) in, described inert gas is the mixed gas of nitrogen, argon gas or both.