CN109888176B - Positive electrode of lithium-sulfur secondary battery - Google Patents
Positive electrode of lithium-sulfur secondary battery Download PDFInfo
- Publication number
- CN109888176B CN109888176B CN201910059149.XA CN201910059149A CN109888176B CN 109888176 B CN109888176 B CN 109888176B CN 201910059149 A CN201910059149 A CN 201910059149A CN 109888176 B CN109888176 B CN 109888176B
- Authority
- CN
- China
- Prior art keywords
- sulfur
- lithium
- positive electrode
- storage material
- lithium storage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention aims to provide a positive electrode of a lithium-sulfur secondary battery, which comprises 1-5 sulfur-containing positive electrode material layers and 1-5 lithium storage material layers containing transition metal elements, wherein the sulfur-containing positive electrode material layers and the lithium storage material layers are alternately coated. The total thickness of the positive electrode is 50-800 micrometers, the thickness of the sulfur-containing positive electrode material layer is 1-500 micrometers, and the thickness of the lithium storage material layer is 1-200 micrometers. The electrode provided by the invention can inhibit shuttle effect, has lithium storage performance and can provide partial capacity; can provide more active sites for lithium sulfide and improve the utilization rate of sulfur.
Description
Technical Field
The invention relates to the technical field of lithium-sulfur secondary batteries, in particular to a positive electrode of a lithium-sulfur secondary battery.
Background
The lithium-sulfur secondary battery is a high specific energy electrochemical energy storage system, mainly uses sulfur as a positive active substance, uses metallic lithium as a negative electrode, and uses an ether solution of lithium salt as an electrolyte. The theoretical specific capacity of the elemental sulfur is up to 1675mAh/g, which is 10 times of that of the layered lithium cobaltate cathode material. However, sulfur has poor conductivity, and a large amount of a conductive agent is added to make full use of sulfur, which is an active material in the electrode. More importantly, the discharge intermediate product of sulfur is a highly soluble polysulfide ion, which easily diffuses to the negative electrode to undergo a self-discharge reaction with lithium metal (i.e., a "shuttle effect"), resulting in a loss of active material and a lower coulombic efficiency. The discharge product of sulfur, lithium sulfide, is poor in both electrochemical activity and conductivity, and lithium sulfide deposited on inactive sites is not easily reused. The above reasons result in low utilization rate of active materials of lithium-sulfur secondary batteries, low coulombic efficiency, rapid capacity fading, and poor cycle performance. In order to improve the performance of the lithium-sulfur secondary battery, improvements are mainly made in the aspects of battery structure design, compounding of positive electrode materials, electrolyte additives, modification of negative electrode surfaces and the like. Among them, the compounding of positive electrode materials is being studied, and carriers of various components and structures are designed for supporting sulfur. For example, sulfur is supported by various porous carbon materials to improve the conductivity thereof, and a part of polysulfide ions can be adsorbed by the porous nature thereof to suppress the shuttle effect. In addition, because of strong polarity, oxide, sulfide and the like of transition metal can strongly adsorb polysulfide ions, so that the shuttle effect is better inhibited, wherein part of materials also have higher conductivity, and the conductivity of the sulfur positive electrode is improved. In these sulfur-containing cathode materials, the conductive additive and the polysulfide adsorbent tend to occupy a greater specific gravity, thereby reducing the specific capacity of the cathode as a whole. Positive electrode materials with lithium storage activity, such as lithium-containing transition metal oxides, can also be used to adsorb polysulfide ions and provide some capacity. For example, CN105529446A discloses a lithium-sulfur battery composite positive electrode material and a preparation method thereof, wherein a lithium storage material can bind polysulfide ions in a positive electrode region, thereby improving the utilization rate of sulfur. C. S.kim et al report that a composite positive electrode material composed of sulfur and lithium iron phosphate can improve the utilization rate of sulfur and the rate capability of a battery (c. -s.kim, et al, Electrochemistry Communications,2013,32, 35-38). However, the electron conductivity of the composite positive electrode composed of sulfur and lithium storage material is poor, a large amount of conductive carbon needs to be added, and the discharge product of sulfur is easy to accumulate on the surface of the lithium storage material and lose electrochemical activity, so that the cycle performance of the battery formed by the composite positive electrode is poor.
In the structure of a battery (electrode), many researches have been carried out to prepare porous carbon and other materials into a thin film to cover the surface of a sulfur-containing anode or directly coat the thin film on the surface of the sulfur-containing anode to form a double-layer or sulfur-concentration-gradient electrode. For example, CN103972467B discloses a multilayer composite positive electrode for a lithium-sulfur battery, which is composed of a first graphene film layer, a carbon/sulfur active material layer, a second graphene film layer and a polymer layer, wherein the second layer functions as a separator, increases electron and ion transport, and limits the shuttle of polysulfide ions. CN106207088A discloses a gradient multilayer sulfur positive electrode structure, in which the sulfur content of each layer in the multilayer structure is distributed in a gradient manner from inside to outside, the sulfur content of the innermost layer is the highest, the outermost layer does not contain sulfur, a diffusion space is provided for sulfur, the barrier effect on polysulfide ions is enhanced, and the polysulfide ions are limited in an electrode space as much as possible. CN108630890A discloses a lithium sulfur secondary battery anode structure composed of a loose porous layer, a conductive framework layer and a confinement layer covering the surface of an electrode, wherein the confinement layer on the surface of the electrode can limit the diffusion of polysulfide ions and inhibit the shuttle effect. The structure mainly utilizes the adsorption performance of materials such as porous carbon and the like, inhibits the dissolution and shuttle effects of polysulfide ions, and provides certain conductivity. However, the additional adsorption layer occupies a larger volume and mass, does not provide capacity per se, and inevitably reduces the mass specific energy and the volume energy density of the battery as a whole.
Disclosure of Invention
The invention aims to provide a positive electrode of a lithium-sulfur secondary battery, which can inhibit shuttle effect, has lithium storage performance, can provide partial capacity, can provide more active sites for lithium sulfide and improves the utilization rate of sulfur.
The invention provides the following technical scheme:
the positive electrode comprises 1-5 sulfur-containing positive electrode material layers and 1-5 lithium storage material layers containing transition metal elements, wherein the sulfur-containing positive electrode material layers and the lithium storage material layers are alternately coated.
The total thickness of the positive electrode is 50-800 micrometers, the thickness of the sulfur-containing positive electrode material layer is 1-500 micrometers, and the thickness of the lithium storage material layer is 1-200 micrometers.
In the invention, the thickness of each sulfur-containing cathode material layer in the cathode is the same or different, and the thickness of each lithium storage material layer is the same or different.
Preferably, the positive electrode is of a 2-6-layer structure, the total thickness of the positive electrode is 150-180 micrometers, the positive electrode comprises 1-3 sulfur-containing positive electrode material layers and 1-3 lithium storage material layers containing transition metal elements, the sulfur-containing positive electrode material layers are coated alternately, the thickness of each sulfur-containing positive electrode material layer is 10-60 micrometers, and the thickness of each lithium storage material layer is 10-50 micrometers. The lithium storage material layer can inhibit shuttle effect, and more active sites are added to the sulfur-containing positive electrode material layer through the multilayer structure, so that the electrochemical reaction area of sulfur and lithium sulfide can be expanded; however, considering the total thickness of the positive electrode and the fact that the coating and forming are not easy when each layer of the sulfur-containing positive electrode material layer and the lithium storage material layer is too thin, the thickness and the number of layers are easy to prepare and form and have better performance.
The sulfur-containing positive electrode material layer comprises sulfur, conductive carbon and a binder, wherein the mass ratio of the sulfur to the conductive carbon to the binder is 30-90: 10-70: 2 to 20. Preferably, the mass ratio of the sulfur to the conductive carbon to the binder is 40-80: 30-50: 8 to 10. Sulfur has poor conductivity and generally contains some more conductive carbon.
When the sulfur-containing positive electrode material layer is prepared, firstly, a sulfur/carbon composite material is prepared, wherein the sulfur/carbon composite material comprises elemental sulfur and conductive carbon A, and the content of sulfur is controlled to be 20-95%, preferably 50-85%. The conductive carbon A in the sulfur/carbon composite material is selected from one or the combination of at least two of activated carbon, graphene, carbon nano tubes, acetylene black or Ketjen black. Preferably, the conductive carbon a for preparing the sulfur/carbon composite is selected from activated carbon or ketjen black. And mixing the prepared sulfur/carbon composite material with conductive carbon B and a binder to obtain a sulfur-containing cathode material layer, wherein the conductive carbon B is selected from one of graphene, carbon nano tubes and acetylene black. Preferably, the conductive carbon B is selected from acetylene black.
The lithium storage material layer comprises a lithium storage material, conductive carbon and a binder, and the mass ratio of the conductive carbon to the binder is 60-90: 10-30: 1 to 15. Preferably, the mass ratio of the lithium storage material, the conductive carbon and the binder is 70-90: 15-20: 2 to 8. The lithium storage material occupies most of the mass, and as it provides energy, the greater the mass fraction, the higher the battery energy. The conductive carbon plays a conductive role, and the adhesive ensures that the electrode can be formed into a film.
In the present invention, the composition and the mass ratio thereof of each sulfur-containing cathode material layer are the same or different, and the composition and the mass ratio thereof of each lithium storage material layer are the same or different.
The binding agents in the sulfur-containing positive material layer and the lithium storage material layer are selected from oil-based binding agents or water-based binding agents, and the binding agents are selected from polyvinylidene fluoride, nitrile rubber, carboxymethyl cellulose, styrene butadiene rubber or acrylonitrile multipolymer; the polarity of the binder in the sulfur-containing cathode material layer is opposite to that of the binder in the lithium storage material layer.
The conductive carbon in the sulfur-containing cathode material layer and the lithium storage material layer is selected from one of graphene, carbon nanotubes and acetylene black. Preferably, the conductive carbon in the sulfur-containing cathode material layer and the lithium storage material layer is selected from acetylene black.
The lithium storage material is selected from one or a combination of at least two of lithium iron phosphate, ferrous disulfide, ferrous sulfide, lithium vanadate, vanadium pentoxide, lithium vanadium phosphate, lithium cobaltate, lithium nickelate, lithium manganate, lithium nickel manganese cobaltate and lithium titanate. Preferably, the lithium storage material is selected from one or a combination of at least two of ferrous disulfide, ferrous sulfide, lithium vanadate, lithium manganate, vanadium pentoxide or lithium titanate. In order to match the voltage range of the sulfur positive electrode and in consideration of the adsorption capacity to lithium polysulfide, the above-mentioned lithium storage material is preferable.
Preferably, the positive electrode comprises 2-3 sulfur-containing positive electrode material layers and 2-3 lithium storage material layers containing transition metal elements, the sulfur-containing positive electrode material layers and the lithium storage material layers are coated alternately, the total thickness of the positive electrode is 150-180 micrometers, the thickness of each positive electrode material layer is 20-50 micrometers, the thickness of each lithium storage material layer is 20-50 micrometers, lithium storage materials in the lithium storage material layers are selected from lithium manganate or vanadium pentoxide, and the mass ratio of the lithium storage materials to conductive carbon to a binder is 80-85: 10-15: 5. in view of the compatibility of the battery technology, an electrode which is too thin is not easy to coat and form; and the specific selection of the lithium storage material, the performance of the positive electrode of the lithium-sulfur battery prepared by the process range is better.
Preferably, the positive electrode is of a 4-layer structure and sequentially comprises a sulfur-containing positive electrode material layer, a lithium storage material layer, a sulfur-containing positive electrode material layer and a lithium storage material layer from bottom to top, and the thicknesses of the sulfur-containing positive electrode material layer, the lithium storage material layer, the sulfur-containing positive electrode material layer and the lithium storage material layer are 50 micrometers, 20 micrometers, 50 micrometers and 30 micrometers respectively; the mass ratio of sulfur to active carbon in the sulfur/carbon composite material of the sulfur-containing cathode material is 50: 50, the mass ratio of the sulfur/carbon composite material to the acetylene black to the styrene butadiene rubber is 70: 20: 10; the mass ratio of lithium manganese oxide to acetylene black to polyvinylidene fluoride in the lithium storage material layer is 80: 15: 5.
in the invention, the thickness of the lithium storage material layer is correspondingly set according to the thickness of the sulfur-containing cathode material layer, so that the lithium storage material layer has enough adsorption effect on the sulfur-containing cathode material layer and provides more active sites, and the lithium storage material layer can play a role in supporting the sulfur-containing cathode material layer.
The invention has the beneficial effects that the positive electrode material with a multilayer structure is designed, and the lithium storage material layer containing the transition metal element is arranged on the outer side of the sulfur-containing positive electrode material layer, so that the invention has the following three functions: firstly, the compound has stronger polysulfide ion adsorption effect and can inhibit shuttle effect; secondly, the lithium storage battery has lithium storage performance and can provide partial capacity; and thirdly, more active sites can be provided for lithium sulfide, the electrochemical reaction area of sulfur and lithium sulfide is expanded, and the utilization rate of active substances is improved. The lithium-sulfur secondary battery anode provided by the invention has a simple structure, is compatible with the existing lithium ion battery coating process, and can be produced in a large scale.
Drawings
Fig. 1 is a schematic view of a positive electrode structure of a lithium sulfur secondary battery according to the present invention;
fig. 2 is a cyclic voltammogram of the positive electrode of the lithium sulfur secondary battery in example 1;
FIG. 3 is a graph showing cycle characteristics of a positive electrode of a lithium sulfur secondary battery in example 1;
FIG. 4 is a cyclic voltammogram of the positive electrode of the lithium sulfur secondary battery in example 4;
FIG. 5 is a graph showing cycle characteristics of a positive electrode of a lithium sulfur secondary battery in example 4;
fig. 6 is a graph showing cycle characteristics of the positive electrode of the lithium sulfur secondary battery in comparative example 1.
Detailed Description
The present invention will be further described with reference to the following examples and accompanying drawings.
Example 1
(1) Mixing the following components in percentage by mass of 70: 30, heating to 165 ℃ to melt the sulfur and permeate the sulfur into the activated carbon to obtain the sulfur/carbon composite material. The resulting sulfur/carbon composite was mixed with acetylene black and carboxymethyl cellulose at a ratio of 70: 20: 10, adding a proper amount of water to prepare slurry, coating the slurry on an aluminum foil fluid, naturally airing the aluminum foil fluid, and performing vacuum drying at 100 ℃ for 24 hours to obtain a sulfur-containing cathode material layer with the thickness of 100 microns.
(2) Lithium vanadate was mixed with acetylene black and polyvinylidene fluoride in a ratio of 85: 10: 5, grinding and mixing, adding a proper amount of N-methyl pyrrolidone serving as a solvent to prepare slurry, coating the slurry on a sulfur-containing anode material layer, naturally airing, and then drying in vacuum at 100 ℃ for 24 hours to obtain a 50-micron thick anode material.
The obtained lithium-sulfur secondary battery positive electrode with the double-layer structure has the total thickness of 150 micrometers. The performance of the assembled battery is shown in fig. 2 and 3, and the capacity retention rate is 75% after charging and discharging for 100 circles between 1.0V and 3.5V.
Example 2
(1) Mixing the following components in percentage by mass of 70: 30, heating to 165 ℃ to melt the sulfur and permeate the sulfur into the activated carbon to obtain the sulfur/carbon composite material. The resulting sulfur/carbon composite was mixed with acetylene black and carboxymethyl cellulose at a ratio of 70: 20: 10, adding a proper amount of water to prepare slurry, coating the slurry on an aluminum foil fluid, naturally airing the aluminum foil fluid, and performing vacuum drying at 100 ℃ for 24 hours to obtain a sulfur-containing anode material layer with the thickness of 60 microns.
(2) Mixing ferrous disulfide, acetylene black and polyvinylidene fluoride in a weight ratio of 80: 15: 5, grinding and mixing, adding a proper amount of N-methyl pyrrolidone serving as a solvent to prepare slurry, coating the slurry on a sulfur-containing anode material layer, naturally airing, and then drying in vacuum at 100 ℃ for 24 hours, wherein the thickness is 20 microns.
(3) Mixing the components in a mass ratio of 60: 40, grinding and mixing the elemental sulfur and the activated carbon, heating to 165 ℃ to melt the sulfur and infiltrating the sulfur into the activated carbon to obtain the sulfur/carbon composite material. The resulting sulfur/carbon composite was mixed with acetylene black and carboxymethyl cellulose at a ratio of 70: 20: 10, adding a proper amount of water to prepare slurry, coating the slurry on the electrode obtained in the step (2), naturally airing, and performing vacuum drying at 100 ℃ for 24 hours to obtain a sulfur-containing anode material layer with the thickness of 50 microns.
(4) Mixing ferrous disulfide, acetylene black and polyvinylidene fluoride in a weight ratio of 80: 15: 5, grinding and mixing, adding a proper amount of N-methyl pyrrolidone serving as a solvent to prepare slurry, coating the slurry on a sulfur-containing anode material layer, naturally airing, and then drying in vacuum at 100 ℃ for 24 hours, wherein the thickness is 20 microns.
As shown in fig. 1 (1 is aluminum foil fluid, 2 is sulfur-containing cathode material layer, and 3 is lithium storage material layer), the obtained four-layer structure cathode of the lithium-sulfur secondary battery has a total thickness of 150 μm. The capacity retention rate of the battery formed by the method is 75% after the battery is charged and discharged for 100 circles between 1.5V and 3.5V.
Example 3
(1) Mixing the components in a mass ratio of 50: 50, grinding and mixing the elemental sulfur and the activated carbon, heating to 165 ℃ to melt the sulfur and infiltrating the sulfur into the activated carbon to obtain the sulfur/carbon composite material. Mixing the obtained sulfur/carbon composite material with acetylene black and styrene-butadiene rubber emulsion to prepare slurry, wherein the mass ratio of the sulfur/carbon composite material to the acetylene black to the styrene-butadiene rubber is 70: 20: and 10, coating the solution on an aluminum foil fluid, naturally airing, and then drying in vacuum at 100 ℃ for 24 hours to obtain a sulfur-containing anode material layer with the thickness of 100 microns.
(2) Mixing lithium iron phosphate, acetylene black and polyvinylidene fluoride in a proportion of 80: 15: 5, grinding and mixing, adding a proper amount of N-methyl pyrrolidone serving as a solvent to prepare slurry, coating the slurry on a sulfur-containing anode material layer, naturally airing, and then drying in vacuum at 100 ℃ for 24 hours to obtain a 50-micron thick anode material.
The total thickness of the obtained lithium-sulfur secondary battery positive electrode with the double-layer structure is 150 micrometers. The capacity retention rate of the assembled battery after charging and discharging for 100 circles between 1.5V and 3.5V is 70%.
The lithium storage materials have different adsorption performance to polysulfide ions, the lithium storage materials have different charging and discharging platforms from sulfur, the charging and discharging platform potential of the lithium storage materials is generally higher than that of sulfur, and the cycle performance of the lithium storage materials is also different. Therefore, compared with the lithium storage material in example 1 or example 2, the performance is reduced.
Example 4
(1) Mixing the components in a mass ratio of 50: 50, grinding and mixing the elemental sulfur and the activated carbon, heating to 165 ℃ to melt the sulfur and infiltrating the sulfur into the activated carbon to obtain the sulfur/carbon composite material. Mixing the obtained sulfur/carbon composite material with acetylene black and styrene-butadiene rubber emulsion to prepare slurry, wherein the mass ratio of the sulfur/carbon composite material to the acetylene black to the styrene-butadiene rubber is 70: 20: and 10, coating the solution on an aluminum foil fluid, naturally airing, and then drying in vacuum at 100 ℃ for 24 hours to obtain a sulfur-containing cathode material layer with the thickness of 50 microns.
(2) Mixing lithium manganate, acetylene black and polyvinylidene fluoride in a weight ratio of 80: 15: 5, grinding and mixing, adding a proper amount of N-methyl pyrrolidone serving as a solvent to prepare slurry, coating the slurry on a sulfur-containing anode material layer, naturally airing, and then drying in vacuum at 100 ℃ for 24 hours, wherein the thickness is 20 microns.
(3) And (3) coating the slurry obtained in the step (1) on the surface of the electrode obtained in the step (2), naturally airing, and then carrying out vacuum drying at 100 ℃ for 24 hours to obtain a sulfur-containing anode material layer with the thickness of 50 microns.
(4) And (3) coating the coating obtained in the step (2) on a sulfur-containing anode material layer, naturally airing, and then drying in vacuum at 100 ℃ for 24 hours, wherein the thickness is 30 microns.
The total thickness of the obtained four-layer structured positive electrode of the lithium-sulfur secondary battery is 150 microns. The performance of the assembled battery is shown in figures 4 and 5, and the capacity retention rate is 90% after 100 circles of charging and discharging between 1.5V and 3.5V.
Example 5
(1) And (2) mixing the following components in percentage by mass: and (3) grinding and mixing the elemental sulfur of 20 with the activated carbon, heating to 165 ℃ to melt the sulfur, and infiltrating the sulfur into the activated carbon to obtain the sulfur/carbon composite material. Mixing the obtained sulfur/carbon composite material with acetylene black and styrene-butadiene rubber emulsion to prepare slurry, wherein the mass ratio of the sulfur/carbon composite material to the acetylene black to the styrene-butadiene rubber is 70: 20: and 10, coating the solution on an aluminum foil fluid, naturally airing, and then drying in vacuum at 100 ℃ for 24 hours to obtain a sulfur-containing cathode material layer with the thickness of 50 microns.
(2) Mixing vanadium pentoxide with acetylene black and polyvinylidene fluoride in a ratio of 80: 15: 5, grinding and mixing, adding a proper amount of N-methyl pyrrolidone serving as a solvent to prepare slurry, coating the slurry on a sulfur-containing anode material layer, naturally airing, and then drying in vacuum at 100 ℃ for 24 hours, wherein the thickness is 20 microns.
(3) And (3) coating the slurry obtained in the step (1) on the surface of the electrode obtained in the step (2), naturally airing, and then carrying out vacuum drying at 100 ℃ for 24 hours to obtain a sulfur-containing anode material layer with the thickness of 20 microns.
(4) And (3) coating the slurry obtained in the step (2) on a sulfur-containing anode material layer, naturally airing, and then drying in vacuum at 100 ℃ for 24 hours, wherein the thickness is 20 microns.
(5) Mixing the components in a mass ratio of 50: 50, grinding and mixing the elemental sulfur and the activated carbon, heating to 165 ℃ to melt the sulfur and infiltrating the sulfur into the activated carbon to obtain the sulfur/carbon composite material. Mixing the obtained sulfur/carbon composite material with acetylene black and styrene-butadiene rubber emulsion to prepare slurry, wherein the mass ratio of the sulfur/carbon composite material to the acetylene black to the styrene-butadiene rubber is 70: 20: and 10, coating the solution on aluminum foil fluid, naturally airing, and then drying in vacuum at 100 ℃ for 24 hours to obtain a sulfur-containing anode material layer with the thickness of 20 microns.
(6) Mixing vanadium pentoxide with acetylene black and polyvinylidene fluoride in a ratio of 80: 15: 5, grinding and mixing, adding a proper amount of N-methyl pyrrolidone serving as a solvent to prepare slurry, coating the slurry on a sulfur-containing anode material layer, naturally airing, and then drying in vacuum at 100 ℃ for 24 hours to obtain a 50-micron thick anode material.
The total thickness of the obtained six-layer structured lithium-sulfur secondary battery positive electrode is 180 micrometers. The capacity retention rate of the battery formed by the method is 80% after the battery is charged and discharged for 100 circles at 1.5-3.0V.
Comparative example 1
(1) Mixing the components in a mass ratio of 50: 50: and (2) grinding and mixing the elemental sulfur, the activated carbon and the lithium manganate of 20, heating to 165 ℃ to melt the sulfur, and infiltrating the sulfur into the activated carbon and the lithium manganate to obtain the sulfur/carbon/lithium manganate composite material.
(2) Mixing the obtained sulfur/carbon/lithium manganate composite material with acetylene black and polyvinylidene fluoride in a proportion of 70: 20: 10, grinding and mixing, adding a proper amount of N-methyl pyrrolidone serving as a solvent to prepare slurry, coating the slurry on an aluminum foil current collector, naturally airing, and performing vacuum drying at 100 ℃ for 24 hours to obtain a non-layered lithium-sulfur secondary battery anode with the thickness of 150 microns. The charge-discharge cycle performance of the assembled battery between 1.5V and 3.5V is shown in figure 6, and the capacity retention rate is 55% after 100 cycles.
Claims (5)
1. The positive electrode of the lithium-sulfur secondary battery is characterized by comprising 1-5 sulfur-containing positive electrode material layers and 1-5 lithium storage material layers containing transition metal elements, wherein the sulfur-containing positive electrode material layers and the lithium storage material layers are alternately coated;
the sulfur-containing positive material layer comprises elemental sulfur, conductive carbon and a binder, and the mass ratio of the elemental sulfur to the conductive carbon to the binder is 30-90: 10-70: 2-20; the lithium storage material layer comprises a lithium storage material, conductive carbon and a binder, and the mass ratio of the conductive carbon to the binder is 60-90: 10-30: 1-15;
the binder is selected from an oily binder or a water-based binder, and is selected from polyvinylidene fluoride, nitrile rubber, carboxymethyl cellulose, styrene butadiene rubber or acrylonitrile multipolymer; the polarity of the binder in the sulfur-containing cathode material layer is opposite to that of the binder in the lithium storage material layer.
2. The positive electrode for a lithium-sulfur secondary battery according to claim 1, wherein the total thickness of the positive electrode is 50 to 800 μm, the thickness of the sulfur-containing positive electrode material layer is 1 to 500 μm, and the thickness of the lithium storage material layer is 1 to 200 μm.
3. The positive electrode for a lithium sulfur secondary battery according to claim 2, wherein the total thickness of the positive electrode is 150 to 180 micrometers, the positive electrode comprises 1 to 3 sulfur-containing positive electrode material layers and 1 to 3 lithium storage material layers containing a transition metal element, which are alternately coated, the sulfur-containing positive electrode material layers have a thickness of 10 to 60 micrometers, and the lithium storage material layers have a thickness of 10 to 50 micrometers.
4. The positive electrode for a lithium-sulfur secondary battery according to claim 1, wherein the lithium storage material is selected from one or a combination of at least two of lithium iron phosphate, ferrous disulfide, ferrous sulfide, lithium vanadate, vanadium pentoxide, lithium vanadium phosphate, lithium cobaltate, lithium nickelate, lithium manganate, lithium nickel manganese cobaltate, lithium titanate.
5. The positive electrode of the lithium-sulfur secondary battery according to claim 4, wherein the positive electrode comprises 2-3 sulfur-containing positive electrode material layers and 2-3 lithium storage material layers containing a transition metal element, the positive electrode is coated alternately, the total thickness of the positive electrode is 150-180 micrometers, the thickness of the positive electrode material layers is 20-50 micrometers, the thickness of the lithium storage material layers is 20-50 micrometers, the lithium storage material in the lithium storage material layers is selected from lithium manganate or vanadium pentoxide, and the mass ratio of the lithium storage material, the conductive carbon and the binder is 80-85: 10-15: 5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910059149.XA CN109888176B (en) | 2019-01-22 | 2019-01-22 | Positive electrode of lithium-sulfur secondary battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910059149.XA CN109888176B (en) | 2019-01-22 | 2019-01-22 | Positive electrode of lithium-sulfur secondary battery |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109888176A CN109888176A (en) | 2019-06-14 |
| CN109888176B true CN109888176B (en) | 2020-12-01 |
Family
ID=66926513
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910059149.XA Active CN109888176B (en) | 2019-01-22 | 2019-01-22 | Positive electrode of lithium-sulfur secondary battery |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109888176B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114079038B (en) * | 2020-08-12 | 2023-09-26 | 清华大学 | High-sulfur-load lithium-sulfur battery positive electrode and preparation method thereof |
| CN113506953B (en) * | 2021-06-02 | 2022-11-22 | 郑州轻工业大学 | Application of lithium vanadium phosphate in coating of lithium-sulfur battery diaphragm |
| CN114023919B (en) * | 2021-10-20 | 2023-08-08 | 中国科学院上海硅酸盐研究所 | High-load sulfur positive electrode and lithium sulfur battery containing high-load sulfur positive electrode |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101346835A (en) * | 2005-12-27 | 2009-01-14 | 松下电器产业株式会社 | Electrode for lithium secondary battery and lithium secondary battery using same |
| CN103972467A (en) * | 2013-02-06 | 2014-08-06 | 中国科学院金属研究所 | Lithium-sulfur battery multilayer composite positive electrode and preparation method thereof |
| CN104081561A (en) * | 2011-12-14 | 2014-10-01 | 罗伯特·博世有限公司 | Lithium-sulphur cell cathode with layer system |
| CN105529446A (en) * | 2016-01-20 | 2016-04-27 | 中南大学 | Lithium-sulfur battery composite positive electrode material and preparation method and application therefor |
| CN106463682A (en) * | 2014-04-30 | 2017-02-22 | 罗伯特·博世有限公司 | Protective layer system for a metallic lithium anode |
| CN108987729A (en) * | 2018-08-29 | 2018-12-11 | 武汉科技大学 | A kind of lithium sulfur battery anode material and preparation method thereof and lithium-sulfur cell |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103187570B (en) * | 2011-12-28 | 2015-09-30 | 清华大学 | The preparation method of sulphur-graphene composite material |
| CN107579201B (en) * | 2017-09-14 | 2023-07-18 | 珠海格力电器股份有限公司 | Multilayer body and preparation method thereof |
| CN108987725A (en) * | 2018-08-21 | 2018-12-11 | 南开大学 | A kind of anode composite material of lithium sulfur battery and preparation method thereof |
-
2019
- 2019-01-22 CN CN201910059149.XA patent/CN109888176B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101346835A (en) * | 2005-12-27 | 2009-01-14 | 松下电器产业株式会社 | Electrode for lithium secondary battery and lithium secondary battery using same |
| CN104081561A (en) * | 2011-12-14 | 2014-10-01 | 罗伯特·博世有限公司 | Lithium-sulphur cell cathode with layer system |
| CN103972467A (en) * | 2013-02-06 | 2014-08-06 | 中国科学院金属研究所 | Lithium-sulfur battery multilayer composite positive electrode and preparation method thereof |
| CN106463682A (en) * | 2014-04-30 | 2017-02-22 | 罗伯特·博世有限公司 | Protective layer system for a metallic lithium anode |
| CN105529446A (en) * | 2016-01-20 | 2016-04-27 | 中南大学 | Lithium-sulfur battery composite positive electrode material and preparation method and application therefor |
| CN108987729A (en) * | 2018-08-29 | 2018-12-11 | 武汉科技大学 | A kind of lithium sulfur battery anode material and preparation method thereof and lithium-sulfur cell |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109888176A (en) | 2019-06-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Huang et al. | Multi-functional separator/interlayer system for high-stable lithium-sulfur batteries: Progress and prospects | |
| CN109888176B (en) | Positive electrode of lithium-sulfur secondary battery | |
| CN109671987B (en) | Winding type lithium slurry battery | |
| US20150364755A1 (en) | Silicon Oxide (SiO) Anode Enabled by a Conductive Polymer Binder and Performance Enhancement by Stabilized Lithium Metal Power (SLMP) | |
| EP3486992B1 (en) | Battery | |
| KR20100014606A (en) | Optimised energy storage device | |
| Cheng et al. | Oxidized multiwall carbon nanotube modified separator for high performance lithium–sulfur batteries with high sulfur loading | |
| CN108807843A (en) | MULTILAYER COMPOSITE cathode and preparation method thereof and alkali metal battery including it | |
| CN105552281A (en) | Production method of carbon coated diaphragm used for lithium sulfur battery | |
| CN106129376A (en) | The lithium ion battery cathode pole piece of Graphene hollow ball load stannic disulfide composite | |
| CN111370626A (en) | Synergistic mechanism lithium-sulfur diaphragm, preparation method thereof and lithium-sulfur battery | |
| CN111430664A (en) | High-load electrode, preparation method and lithium ion battery thereof | |
| US20160285110A1 (en) | Positive electrode for lithium air battery and lithium air battery comprising the same | |
| US20160285085A1 (en) | Electrodes for energy storage devices and methods for their preparation | |
| CN104716405A (en) | Lithium-air battery structure | |
| KR20200028258A (en) | Anode for secondary battery and Secondary battery including the same | |
| CN111312990A (en) | Multifunctional composite negative plate, preparation method and secondary battery | |
| CN105374982A (en) | Electrode structure of lithium sulfur battery and processing technology therefor | |
| CN107331528A (en) | Multi-layer composite electrode and the lithium ion battery electric capacity using the electrode | |
| CN105551822A (en) | High-temperature hybrid supercapacitor and fabrication method thereof | |
| CN115312692A (en) | Positive lithium-rich composite pole piece and preparation method and application thereof | |
| CN106207097A (en) | A kind of lithium-sulfur cell pole piece and the preparation method of battery thereof | |
| CN108666533B (en) | Preparation method and application of sulfur electrode of lithium-sulfur battery | |
| CN112825349A (en) | Composite positive electrode plate and lithium secondary battery | |
| CN205900716U (en) | High power super capacitor lithium cell |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |