CN105256275A

CN105256275A - Electrolyte layer material lithium phosphate target material powder metallurgy preparation technology for thin film lithium batteries

Info

Publication number: CN105256275A
Application number: CN201510736619.3A
Authority: CN
Inventors: 贾泽夏; 庄志杰
Original assignee: Mike Material Technology (suzhou) Co Ltd
Current assignee: Mike Material Technology (suzhou) Co Ltd
Priority date: 2015-11-03
Filing date: 2015-11-03
Publication date: 2016-01-20

Abstract

The invention relates to an electrolyte layer material lithium phosphate target material powder metallurgy preparation technology for thin film lithium batteries. Lithium phosphate powder is subject to ball milling and screening, and isostatic cool pressing is carried out after die filling is carried out; a molded biscuit is taken out and arranged in a vacuum sintering furnace for stage warming sintering; and finally, a sintered and cooled target material is taken out to be machined, and then a lithium phosphate target material finished product in the needed size can be manufactured; and the lithium phosphate target material prepared above is subject to scanning electron microscope analysis, obtained crystalline grains are wee in size and high in density, and the density is about 98.4%. The prepared lithium phosphate target material is wee in size and high in density, it is guaranteed that the texture of the material is even, the performance is stable, and the good cold and heat machining performance is obtained; and under the appropriate condition, the target material is sputtered, a thin film with the excellent performance can be obtained, and the energy storage amount and the circulation frequency of full-solid thin film lithium batteries are accordingly improved.

Description

Film lithium cell electrolyte layer lithium phosphate target powder metallurgy preparation technique

Technical field

The present invention relates to the C23C sputtering method coating technology in IPC classification, belong to and be applied to electrochemical field new and high technology material, especially film lithium cell electrolyte layer lithium phosphate target powder metallurgy preparation technique.

Background technology

Film lithium cell is the important directions of lithium ion battery development, except having the advantage of conventional lithium-ion battery, as high in voltage, memory-less effect, environmentally friendly outside, film lithium cell also has extremely high energy density, be known as wireless cycle performance, and truly all solid state, obtain very large market at micro-energy field.Solid-State Thin Film Li-Ion Batteries owing to having high power density, low self-discharge rate, excellent charge-discharge performance, shape and size can design arbitrarily, and reveal without solution, do not explode, the advantage such as use safety, obtain extensive concern at home and abroad in recent years, Countries realizes suitability for industrialized production.

Common prepares film lithium cell electrolyte layer lithium phosphate target (Li ₃po ₄) method of target adds sintering for colding pressing.In cold pressure procedure, the binding agent adding 0.5% ~ 2% can strengthen the formability of biscuit, but too increases the foreign matter content of target simultaneously.Because the relative density of biscuit is 60% ~ 70%, after target has sintered, the relative density of target can only reach 70% ~ 90%.

Thin-film electrolyte for all solid-state thin-film lithium battery requires to have higher ionic conductivity (> 10 ^-7s/cm), very low electronic conductivity and activation energy, and with have good stability during electrode material contacts.At present, the above electrolyte system required can be met little simultaneously, limit the development of solid-State Thin Film Li-Ion Batteries.Therefore in the urgent need to finding and developing a kind of thin-film electrolyte material of good performance.

The lithium phosphate target that normal pressure atmosphere sintering process is conventionally prepared, its grain-size is larger, and density is not high yet.Under suitable condition, the energy storage capacity and the cycle index that employ the solid-State Thin Film Li-Ion Batteries that these targets of sputtering obtain are also lower.

Comparatively close prior art is less, and published patent documentation does not have good reference value yet.

Summary of the invention

The object of this invention is to provide a kind of film lithium cell electrolyte layer lithium phosphate target powder metallurgy preparation technique, the deficiencies in the prior art can be overcome, for production volume is little, the solid-State Thin Film Li-Ion Batteries of high-energy-density, life-span length provides the electrolytic thin-membrane with high ionic conductivity and low electronic conductivity.

Object of the present invention will be realized by following technical measures: step of preparation process:

1) choosing Trilithium phosphate (Li3Po4) powder that purity is greater than 99.95% is raw material, then carries out ball-milling processing to material powder, and obtain fine size and uniform spherical particle, mean particle size range is 50 ~ 100nm;

2) powder processed is carried out die-filling;

3) carry out isostatic cool pressing processing after die-filling, the density of material can be improved, pressure range 100MPa ~ 300MPa;

4) isostatic cool pressing is complete, shaping blank is taken out and is placed in vacuum sintering furnace and sinters, sintering processing is interim intensification, first with the heat-up rate of 100 ~ 200 DEG C/h, temperature is risen to 800 ~ 900 DEG C, be incubated 2 ~ 4 hours, then rise to 900 ~ 1200 DEG C with the heat-up rate of 200 ~ 400 DEG C/h, be incubated and be down to normal temperature after 4 ~ 24 hours, cooling rate is 50 ~ 100 DEG C/h;

5) taking out sintering the target cooled, mechanical workout being carried out to it, obtains described lithium phosphate target finished product.

Especially, choose purity be 99.95% Trilithium phosphate powder be raw material, carry out ball milling, screening process to it, obtain fine size and uniform spherical particle, median size is 80nm; The powder processed is carried out die-filling; Carry out isostatic cool pressing after die-filling, pressure is 100MPa, and the biscuit relative density after repressed is 60%; Isostatic cool pressing is complete, shaping biscuit is taken out and is placed in vacuum sintering furnace and carry out stage intensification sintering, first with the heat-up rate of 100 DEG C/h, temperature is risen to 800 DEG C, be incubated 4 hours, then 1200 DEG C are risen to the heat-up rate of 200 DEG C/h, be incubated and be down to normal temperature after 12 hours, cooling rate is 50 DEG C/h; Finally taking out sintering the target cooled, mechanical workout being carried out to it and can obtain desired size cobalt acid lithium target finished product; Scanning electron microscope analysis is carried out to the cobalt of above-mentioned preparation acid lithium target, can obtain that its grain-size is tiny and density is high, be about 98.4%.

Advantage of the present invention and effect: the lithium phosphate target grain-size prepared is tiny and density is high, ensure that materials microstructure is even, stable performance, and good hot and cold processing characteristics; Sputter these targets under proper condition, the film of excellent performance can be obtained, thus improve energy storage capacity and the cycle index of solid-State Thin Film Li-Ion Batteries.

Embodiment

The principle of the invention is, ball milling, screening process are carried out to Trilithium phosphate powder, isostatic cool pressing is carried out after die-filling, shaping biscuit is taken out and is placed in vacuum sintering furnace and carry out stage intensification sintering, finally taking out sintering the target cooled, mechanical workout being carried out to it and can obtain desired size cobalt acid lithium target finished product.

In the present invention, step of preparation process:

2) powder processed is carried out die-filling;

Below in conjunction with embodiment, the invention will be further described.

Embodiment 1: choose purity be 99.95% Trilithium phosphate powder be raw material, carry out ball milling, screening process to it, obtain fine size and uniform spherical particle, median size is 80nm; The powder processed is carried out die-filling; Carry out isostatic cool pressing after die-filling, pressure is 100MPa, and the biscuit relative density after repressed is about 60%; Isostatic cool pressing is complete, shaping biscuit is taken out and is placed in vacuum sintering furnace and carry out stage intensification sintering, first with the heat-up rate of 100 DEG C/h, temperature is risen to 800 DEG C, be incubated 4 hours, then 1200 DEG C are risen to the heat-up rate of 200 DEG C/h, be incubated and be down to normal temperature after 12 hours, cooling rate is 50 DEG C/h; Finally taking out sintering the target cooled, mechanical workout being carried out to it and can obtain desired size cobalt acid lithium target finished product.Scanning electron microscope analysis is carried out to the cobalt of above-mentioned preparation acid lithium target, can obtain that its grain-size is tiny and density is high, be about 98.4%.

Claims

1. film lithium cell electrolyte layer lithium phosphate target powder metallurgy preparation technique, is characterized in that, step of preparation process:

1) choosing the Trilithium phosphate powder that purity is greater than 99.95% is raw material, then carries out ball-milling processing to material powder, and obtain fine size and uniform spherical particle, mean particle size range is 50 ~ 100nm;

2) powder processed is carried out die-filling;

2. film lithium cell electrolyte layer lithium phosphate target powder metallurgy preparation technique as claimed in claim 1, it is characterized in that, choose purity be 99.95% Trilithium phosphate powder be raw material, ball milling, screening process are carried out to it, obtain fine size and uniform spherical particle, median size is 80nm; The powder processed is carried out die-filling; Carry out isostatic cool pressing after die-filling, pressure is 100MPa, and the biscuit relative density after repressed is 60%; Isostatic cool pressing is complete, shaping biscuit is taken out and is placed in vacuum sintering furnace and carry out stage intensification sintering, first with the heat-up rate of 100 DEG C/h, temperature is risen to 800 DEG C, be incubated 4 hours, then 1200 DEG C are risen to the heat-up rate of 200 DEG C/h, be incubated and be down to normal temperature after 12 hours, cooling rate is 50 DEG C/h; Finally taking out sintering the target cooled, mechanical workout being carried out to it and can obtain desired size cobalt acid lithium target finished product; Scanning electron microscope analysis is carried out to the cobalt of above-mentioned preparation acid lithium target, can obtain that its grain-size is tiny and density is high, be about 98.4%.