Patent
US 10,749,170GRAPHENE-COATED METAL OXIDE SPINEL CATHODES
Mark C. Hersam
US
Copyright © 2026 Matter42. All rights reserved.
Patent
Atlas literature
Patent
US 10,749,170Patent drawings and their descriptions. Click a drawing to enlarge it.
Figure 1 shows a schematic illustration of the sample preparation process. Graphene may be grown using chemical vapor deposition (CVD) on copper foil and then transferred on top of 15 spinel LiMn 2 0 4 (LMO) thin fi lms using a poly(methyl methacrylate) (PMMA) transfer method. The thin film LMO may …
Figure 2A shows an SEM image of spinel LMO thin films.
Figure 2B shows a grazing incidence X-ray diffraction of LMO thin fi lms showing a spinel crystal structure. 20
Figure 2C shows an SEM image of graphene transferred onto a LMO thin film; the graphene is indicated by arrows.
Figure 2D shows a Raman spectrum of graphene-coated LMO obtained using a Raman laser wavelength of 514 nm. The shape of the 2 D (2700 cm 1) peak and the ratio of 2 D to G (1580 cm⁻¹) intensity are characteristic of single-layer graphene. The high-intensity peak at-620 25 cm⁻¹ is attributed to the …
Figure 3A shows capacity retention of LMO and graphene-LMO thin films versus cycle 30 number for LMO and graphene-coated LMO cathodes in lithium half cells at 100 mA/cm 3.
Figures 3B shows capacity retention versus cycle number for uncoated and graphene- coated LMO cathodes in graphite/LMO full cells at various cu rr ent rates (100-500 mA/cm 3).
Figure 4A shows a cyclic voltammetry curve of LMO thin film vs. lithium.
Figure 4B shows a voltage-capacity curve of LMO thin film vs. lithium. 5
Figure 4C shows a cyclic voltammetry curveof graphene-coated LMO thin films vs. lithium.
Figure 4D shows a voltage-capacity curve of graphene-coated LMO thin fi lms vs. lithium.
Figure 4E shows a voltage-capacity curve of uncoated LMO thin films vs. graphite. 10
Figure 4F shows a voltage-capacity curves of graphene-coated LMO thin films vs. graphite.
Figure 4G shows volumetric capacity of LMO and graphene-coated LMO thin fi lms vs. lithium.
Figure 4 H shows volumetric capacity of LMO and graphene-coated LMO thin fi lms vs. 15 graphite.
Figure 5A shows XPS depth profiling of the Mn 2P peaks for graphene-coated LMO cathodes after 750 lithiation/delithiation cycles.
Figure 5B shows XPS depth pro fi ling of the Mn 2P peaks for uncoated LMO cathodes after 350 lithiation/delithiation cycles. 20
Figure 5C shows no rm alized Li 1S peaks for graphene-coated LMO after 750 lithiation/delithiation cycles.
Figure 5D shows no rm alized Li 1S peaks for uncoated LMO after 350 lithiation/delithiation cycles.
Figure 5E shows the variation of Mn 2P (3/2) peak intensity versus depth for graphene- 25 coated LMO and uncoated LMO after lithiation/delithiation in a lithium half cell (3.5 to 4.4 V) for 750 and 350 cycles, respectively.
Figure 5F shows the variation of Mn 2P (3/2) peak intensity versus depth for graphene-coated LMO and uncoated LMO after lithiation/delithiation in graphite/LMO full cells (2 to 4.4 V) for 100 cycles. 30
Figure 6A shows the effect of graphene on SE I formation of LMO cathodes by XPS depth pro fi les of O 1S peak for graphene-coated LMO after cycling.
Figure 6B shows the effect of graphene on SE I fo rm ation of LMO cathodes by XPS depth profiles of O 15 peak for uncoated LMO after cycling.
Figure 6C shows bright-field cross-sectional STEM images of graphene-coated LMO after cycling. 5
Figure 6D shows bright-field cross-sectional STEM images of uncoated LMO after cycling.
Figure 6E shows cross-sectional HRTEM images of graphene-coated LMO after cycling.
Figure 6F shows cross-sectional HRTEM images of uncoated LMO after cycling.
Figure 7A shows a grazing incidence x-ray diffraction measurement of the LMO and graphene-coated 10 LMO films after cycling.
Figure 7B shows an SEM image of the LMO cathode after 350 cycles.
Figure 7C shows a Raman spectrum of graphene-coated LMO after 750 cycles. The sharp peak to the left of the 2D peak (~ 2400 cm-) is due to ambient nitrogen.
Figure 7D shows an SEM image of the graphene-coated LMO after 750 cycles. 15
Figure 8A illustrates a diffusion energy barrier through DV(5-8-5) in graphene for Mn approaching the graphene sheet. The inset shows the structure of the DV in the closed configuration with Mn near the graphene sheet (0.6 A away from graphene).
Figure 8B illustrates a Mn potential energy profile for Mn within the DV. The inset shows the structure of the DV in the open configuration. The insets are truncations near the DV 20 of the K e kule 156-atom graphene flake model. For reference, the calculated binding energies for Li and Mn for the …
Figure 9A illustrates a LMO (001) surface in thin film LMO electrodes for a graphene patch adsorbed perpendicular (90 0) to the surface. 25
Figure 9B illustrates a LMO (001) surface in thin film LMO electrodes for a graphene patch adsorbed at 45 0 relative to the surface.
Figure 9C illustrates a LMO (001) surface in thin film LMO electrodes for a graphene patch adsorbed parallel (0 0) relative to the surface.
Figure 10 B illustrates the effect of the 0/45/90 graphene bound to (001) LMO surface (Mn 4 +) and subsurface (Mn.'+ x-). The Fermi level is set as zero in the DOS plots. 5
Figure 11 A shows the chemical structure of a graphene patch adsorbed perpendicularly on a "Long" slab of a (001) Li i 6 Mn 32 O 6 4 surface.
Figure 11B shows the chemical structure of a graphene patch adsorbed perpendicularly on a "Wide" slab of a (001) Li 16 Mn 32 O 6 4 surface.
Figure 11 C shows the majority-spin channel of the Mn 3d projected density of states 10 (DOS) of the 90 0 GP/Li 6 Mn₃₂ O₆₄ (001) surface and the Mn subsurface, where the oxidation states of the Mn atoms are found to be +4.
Figure 12 shows the Mn-O average bond length: Mn₃+ changes its valence to Mn 4 + when the graphene sheet is present, and the average Mn-O bond length in z-direction is reduced. In comparison, Mn 4 + atoms in the subsurface change their valence to Mn 3., and the average Mn-O 15 bond length is …
Figure 13 shows the metal-graphene binding energy (eV) versus displacement from divacancy (A).
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A cathode comprising: a metal oxide spinel film comprising LiM x Mn₂- xO 4, and a graphene film, the graphene film disposed on a surface of the metal oxide film, wherein M is selected from a group comprising Li, Co, Ni, Al, Y, Ti, and Zn and X is any real number greater than or equal to zero and less than or equal to two and wherein the cathode is configured to form a solid electrolyte interphase layer disposed on the graphene film when the cathode is contacted with an electrolyte. Previously presented
The cathode of claim 1, wherein the metal oxide spinel comprises LiMn₂ 04. Previously presented
The cathode of claim 1, wherein the metal oxide spinel further comprises Co, Ni, Al, Y, Ti, or Zn. Previously presented
The cathode of claim 1, wherein M is selected from a group comprising Li, Co, Ni, and Zn. Previously presented
The cathode of claim 1, wherein the metal oxide spinel film has a thickness greater than or equal to 100 nm and less than or equal to 150 nm. Previously presented
The cathode of claim 1, wherein the graphene film comprises a substantially monolayer graphene film. Previously presented
The cathode of claim 1, wherein the graphene film comprises less than or equal to 20 % double-layer graphene islands. Previously presented
The cathode of claim 1, wherein the graphene film is substantially free of vacancy defects. Previously presented
The cathode of claim 1, wherein the metal oxide spinel film comprises a plurality of manganese atoms having a bulk oxidation state and a plurality of manganese atoms having a surface oxidation state, wherein the surface oxidation state is greater than the bulk oxidation state. Previously presented
The cathode of claim 1, wherein the cathode further comprises the solid electrolyte interphase layer disposed on the graphene film and wherein the solid electrolyte interphase layer comprises lithium carbonate. Previously presented
An electrochemical cell comprising the cathode of claim 1, an anode, and an electrolyte. Previously presented
A method for preparing a cathode, the method comprising: (a) obtaining the metal oxide spinel film of claim 1; (b) obtaining a graphene film; and (c) transferring the graphene film onto a surface of the metal oxide spinel film. Previously presented
9-10. Canceled
Canceled
Canceled
Canceled
24-49. Canceled
Canceled
Layer stacks claimed or described, ordered top of device to substrate.
graphene-coated LiMxMn₂-xO₄ spinel cathode
electrochemical cell (lithium-ion battery)
Materials described outside the worked examples.
lithium manganese oxide spinel (LiMxMn₂-xO₄)
LiMxMn₂-xO₄
graphene film
solid electrolyte interphase layer
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
Figure 2A shows an SEM image of spinel LMO thin films.
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
metal oxide spinel film thickness (claimed range) | 100–150 nm | LiMxMn₂-xO₄ |
solid electrolyte interphase film thickness (claimed upper bound) | ≤ 100 nm |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 10,749,170Patent drawings and their descriptions. Click a drawing to enlarge it.
Figure 1 shows a schematic illustration of the sample preparation process. Graphene may be grown using chemical vapor deposition (CVD) on copper foil and then transferred on top of 15 spinel LiMn 2 0 4 (LMO) thin fi lms using a poly(methyl methacrylate) (PMMA) transfer method. The thin film LMO may …
Figure 2A shows an SEM image of spinel LMO thin films.
Figure 2B shows a grazing incidence X-ray diffraction of LMO thin fi lms showing a spinel crystal structure. 20
Figure 2C shows an SEM image of graphene transferred onto a LMO thin film; the graphene is indicated by arrows.
Figure 2D shows a Raman spectrum of graphene-coated LMO obtained using a Raman laser wavelength of 514 nm. The shape of the 2 D (2700 cm 1) peak and the ratio of 2 D to G (1580 cm⁻¹) intensity are characteristic of single-layer graphene. The high-intensity peak at-620 25 cm⁻¹ is attributed to the …
Figure 3A shows capacity retention of LMO and graphene-LMO thin films versus cycle 30 number for LMO and graphene-coated LMO cathodes in lithium half cells at 100 mA/cm 3.
Figures 3B shows capacity retention versus cycle number for uncoated and graphene- coated LMO cathodes in graphite/LMO full cells at various cu rr ent rates (100-500 mA/cm 3).
Figure 4A shows a cyclic voltammetry curve of LMO thin film vs. lithium.
Figure 4B shows a voltage-capacity curve of LMO thin film vs. lithium. 5
Figure 4C shows a cyclic voltammetry curveof graphene-coated LMO thin films vs. lithium.
Figure 4D shows a voltage-capacity curve of graphene-coated LMO thin fi lms vs. lithium.
Figure 4E shows a voltage-capacity curve of uncoated LMO thin films vs. graphite. 10
Figure 4F shows a voltage-capacity curves of graphene-coated LMO thin films vs. graphite.
Figure 4G shows volumetric capacity of LMO and graphene-coated LMO thin fi lms vs. lithium.
Figure 4 H shows volumetric capacity of LMO and graphene-coated LMO thin fi lms vs. 15 graphite.
Figure 5A shows XPS depth profiling of the Mn 2P peaks for graphene-coated LMO cathodes after 750 lithiation/delithiation cycles.
Figure 5B shows XPS depth pro fi ling of the Mn 2P peaks for uncoated LMO cathodes after 350 lithiation/delithiation cycles. 20
Figure 5C shows no rm alized Li 1S peaks for graphene-coated LMO after 750 lithiation/delithiation cycles.
Figure 5D shows no rm alized Li 1S peaks for uncoated LMO after 350 lithiation/delithiation cycles.
Figure 5E shows the variation of Mn 2P (3/2) peak intensity versus depth for graphene- 25 coated LMO and uncoated LMO after lithiation/delithiation in a lithium half cell (3.5 to 4.4 V) for 750 and 350 cycles, respectively.
Figure 5F shows the variation of Mn 2P (3/2) peak intensity versus depth for graphene-coated LMO and uncoated LMO after lithiation/delithiation in graphite/LMO full cells (2 to 4.4 V) for 100 cycles. 30
Figure 6A shows the effect of graphene on SE I formation of LMO cathodes by XPS depth pro fi les of O 1S peak for graphene-coated LMO after cycling.
Figure 6B shows the effect of graphene on SE I fo rm ation of LMO cathodes by XPS depth profiles of O 15 peak for uncoated LMO after cycling.
Figure 6C shows bright-field cross-sectional STEM images of graphene-coated LMO after cycling. 5
Figure 6D shows bright-field cross-sectional STEM images of uncoated LMO after cycling.
Figure 6E shows cross-sectional HRTEM images of graphene-coated LMO after cycling.
Figure 6F shows cross-sectional HRTEM images of uncoated LMO after cycling.
Figure 7A shows a grazing incidence x-ray diffraction measurement of the LMO and graphene-coated 10 LMO films after cycling.
Figure 7B shows an SEM image of the LMO cathode after 350 cycles.
Figure 7C shows a Raman spectrum of graphene-coated LMO after 750 cycles. The sharp peak to the left of the 2D peak (~ 2400 cm-) is due to ambient nitrogen.
Figure 7D shows an SEM image of the graphene-coated LMO after 750 cycles. 15
Figure 8A illustrates a diffusion energy barrier through DV(5-8-5) in graphene for Mn approaching the graphene sheet. The inset shows the structure of the DV in the closed configuration with Mn near the graphene sheet (0.6 A away from graphene).
Figure 8B illustrates a Mn potential energy profile for Mn within the DV. The inset shows the structure of the DV in the open configuration. The insets are truncations near the DV 20 of the K e kule 156-atom graphene flake model. For reference, the calculated binding energies for Li and Mn for the …
Figure 9A illustrates a LMO (001) surface in thin film LMO electrodes for a graphene patch adsorbed perpendicular (90 0) to the surface. 25
Figure 9B illustrates a LMO (001) surface in thin film LMO electrodes for a graphene patch adsorbed at 45 0 relative to the surface.
Figure 9C illustrates a LMO (001) surface in thin film LMO electrodes for a graphene patch adsorbed parallel (0 0) relative to the surface.
Figure 10 B illustrates the effect of the 0/45/90 graphene bound to (001) LMO surface (Mn 4 +) and subsurface (Mn.'+ x-). The Fermi level is set as zero in the DOS plots. 5
Figure 11 A shows the chemical structure of a graphene patch adsorbed perpendicularly on a "Long" slab of a (001) Li i 6 Mn 32 O 6 4 surface.
Figure 11B shows the chemical structure of a graphene patch adsorbed perpendicularly on a "Wide" slab of a (001) Li 16 Mn 32 O 6 4 surface.
Figure 11 C shows the majority-spin channel of the Mn 3d projected density of states 10 (DOS) of the 90 0 GP/Li 6 Mn₃₂ O₆₄ (001) surface and the Mn subsurface, where the oxidation states of the Mn atoms are found to be +4.
Figure 12 shows the Mn-O average bond length: Mn₃+ changes its valence to Mn 4 + when the graphene sheet is present, and the average Mn-O bond length in z-direction is reduced. In comparison, Mn 4 + atoms in the subsurface change their valence to Mn 3., and the average Mn-O 15 bond length is …
Figure 13 shows the metal-graphene binding energy (eV) versus displacement from divacancy (A).
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A cathode comprising: a metal oxide spinel film comprising LiM x Mn₂- xO 4, and a graphene film, the graphene film disposed on a surface of the metal oxide film, wherein M is selected from a group comprising Li, Co, Ni, Al, Y, Ti, and Zn and X is any real number greater than or equal to zero and less than or equal to two and wherein the cathode is configured to form a solid electrolyte interphase layer disposed on the graphene film when the cathode is contacted with an electrolyte. Previously presented
The cathode of claim 1, wherein the metal oxide spinel comprises LiMn₂ 04. Previously presented
The cathode of claim 1, wherein the metal oxide spinel further comprises Co, Ni, Al, Y, Ti, or Zn. Previously presented
The cathode of claim 1, wherein M is selected from a group comprising Li, Co, Ni, and Zn. Previously presented
The cathode of claim 1, wherein the metal oxide spinel film has a thickness greater than or equal to 100 nm and less than or equal to 150 nm. Previously presented
The cathode of claim 1, wherein the graphene film comprises a substantially monolayer graphene film. Previously presented
The cathode of claim 1, wherein the graphene film comprises less than or equal to 20 % double-layer graphene islands. Previously presented
The cathode of claim 1, wherein the graphene film is substantially free of vacancy defects. Previously presented
The cathode of claim 1, wherein the metal oxide spinel film comprises a plurality of manganese atoms having a bulk oxidation state and a plurality of manganese atoms having a surface oxidation state, wherein the surface oxidation state is greater than the bulk oxidation state. Previously presented
The cathode of claim 1, wherein the cathode further comprises the solid electrolyte interphase layer disposed on the graphene film and wherein the solid electrolyte interphase layer comprises lithium carbonate. Previously presented
An electrochemical cell comprising the cathode of claim 1, an anode, and an electrolyte. Previously presented
A method for preparing a cathode, the method comprising: (a) obtaining the metal oxide spinel film of claim 1; (b) obtaining a graphene film; and (c) transferring the graphene film onto a surface of the metal oxide spinel film. Previously presented
9-10. Canceled
Canceled
Canceled
Canceled
24-49. Canceled
Canceled
Layer stacks claimed or described, ordered top of device to substrate.
graphene-coated LiMxMn₂-xO₄ spinel cathode
electrochemical cell (lithium-ion battery)
Materials described outside the worked examples.
lithium manganese oxide spinel (LiMxMn₂-xO₄)
LiMxMn₂-xO₄
graphene film
solid electrolyte interphase layer
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
Figure 2A shows an SEM image of spinel LMO thin films.
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
metal oxide spinel film thickness (claimed range) | 100–150 nm | LiMxMn₂-xO₄ |
solid electrolyte interphase film thickness (claimed upper bound) | ≤ 100 nm |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 10,749,170Patent drawings and their descriptions. Click a drawing to enlarge it.
Figure 1 shows a schematic illustration of the sample preparation process. Graphene may be grown using chemical vapor deposition (CVD) on copper foil and then transferred on top of 15 spinel LiMn 2 0 4 (LMO) thin fi lms using a poly(methyl methacrylate) (PMMA) transfer method. The thin film LMO may …
Figure 2A shows an SEM image of spinel LMO thin films.
Figure 2B shows a grazing incidence X-ray diffraction of LMO thin fi lms showing a spinel crystal structure. 20
Figure 2C shows an SEM image of graphene transferred onto a LMO thin film; the graphene is indicated by arrows.
Figure 2D shows a Raman spectrum of graphene-coated LMO obtained using a Raman laser wavelength of 514 nm. The shape of the 2 D (2700 cm 1) peak and the ratio of 2 D to G (1580 cm⁻¹) intensity are characteristic of single-layer graphene. The high-intensity peak at-620 25 cm⁻¹ is attributed to the …
Figure 3A shows capacity retention of LMO and graphene-LMO thin films versus cycle 30 number for LMO and graphene-coated LMO cathodes in lithium half cells at 100 mA/cm 3.
Figures 3B shows capacity retention versus cycle number for uncoated and graphene- coated LMO cathodes in graphite/LMO full cells at various cu rr ent rates (100-500 mA/cm 3).
Figure 4A shows a cyclic voltammetry curve of LMO thin film vs. lithium.
Figure 4B shows a voltage-capacity curve of LMO thin film vs. lithium. 5
Figure 4C shows a cyclic voltammetry curveof graphene-coated LMO thin films vs. lithium.
Figure 4D shows a voltage-capacity curve of graphene-coated LMO thin fi lms vs. lithium.
Figure 4E shows a voltage-capacity curve of uncoated LMO thin films vs. graphite. 10
Figure 4F shows a voltage-capacity curves of graphene-coated LMO thin films vs. graphite.
Figure 4G shows volumetric capacity of LMO and graphene-coated LMO thin fi lms vs. lithium.
Figure 4 H shows volumetric capacity of LMO and graphene-coated LMO thin fi lms vs. 15 graphite.
Figure 5A shows XPS depth profiling of the Mn 2P peaks for graphene-coated LMO cathodes after 750 lithiation/delithiation cycles.
Figure 5B shows XPS depth pro fi ling of the Mn 2P peaks for uncoated LMO cathodes after 350 lithiation/delithiation cycles. 20
Figure 5C shows no rm alized Li 1S peaks for graphene-coated LMO after 750 lithiation/delithiation cycles.
Figure 5D shows no rm alized Li 1S peaks for uncoated LMO after 350 lithiation/delithiation cycles.
Figure 5E shows the variation of Mn 2P (3/2) peak intensity versus depth for graphene- 25 coated LMO and uncoated LMO after lithiation/delithiation in a lithium half cell (3.5 to 4.4 V) for 750 and 350 cycles, respectively.
Figure 5F shows the variation of Mn 2P (3/2) peak intensity versus depth for graphene-coated LMO and uncoated LMO after lithiation/delithiation in graphite/LMO full cells (2 to 4.4 V) for 100 cycles. 30
Figure 6A shows the effect of graphene on SE I formation of LMO cathodes by XPS depth pro fi les of O 1S peak for graphene-coated LMO after cycling.
Figure 6B shows the effect of graphene on SE I fo rm ation of LMO cathodes by XPS depth profiles of O 15 peak for uncoated LMO after cycling.
Figure 6C shows bright-field cross-sectional STEM images of graphene-coated LMO after cycling. 5
Figure 6D shows bright-field cross-sectional STEM images of uncoated LMO after cycling.
Figure 6E shows cross-sectional HRTEM images of graphene-coated LMO after cycling.
Figure 6F shows cross-sectional HRTEM images of uncoated LMO after cycling.
Figure 7A shows a grazing incidence x-ray diffraction measurement of the LMO and graphene-coated 10 LMO films after cycling.
Figure 7B shows an SEM image of the LMO cathode after 350 cycles.
Figure 7C shows a Raman spectrum of graphene-coated LMO after 750 cycles. The sharp peak to the left of the 2D peak (~ 2400 cm-) is due to ambient nitrogen.
Figure 7D shows an SEM image of the graphene-coated LMO after 750 cycles. 15
Figure 8A illustrates a diffusion energy barrier through DV(5-8-5) in graphene for Mn approaching the graphene sheet. The inset shows the structure of the DV in the closed configuration with Mn near the graphene sheet (0.6 A away from graphene).
Figure 8B illustrates a Mn potential energy profile for Mn within the DV. The inset shows the structure of the DV in the open configuration. The insets are truncations near the DV 20 of the K e kule 156-atom graphene flake model. For reference, the calculated binding energies for Li and Mn for the …
Figure 9A illustrates a LMO (001) surface in thin film LMO electrodes for a graphene patch adsorbed perpendicular (90 0) to the surface. 25
Figure 9B illustrates a LMO (001) surface in thin film LMO electrodes for a graphene patch adsorbed at 45 0 relative to the surface.
Figure 9C illustrates a LMO (001) surface in thin film LMO electrodes for a graphene patch adsorbed parallel (0 0) relative to the surface.
Figure 10 B illustrates the effect of the 0/45/90 graphene bound to (001) LMO surface (Mn 4 +) and subsurface (Mn.'+ x-). The Fermi level is set as zero in the DOS plots. 5
Figure 11 A shows the chemical structure of a graphene patch adsorbed perpendicularly on a "Long" slab of a (001) Li i 6 Mn 32 O 6 4 surface.
Figure 11B shows the chemical structure of a graphene patch adsorbed perpendicularly on a "Wide" slab of a (001) Li 16 Mn 32 O 6 4 surface.
Figure 11 C shows the majority-spin channel of the Mn 3d projected density of states 10 (DOS) of the 90 0 GP/Li 6 Mn₃₂ O₆₄ (001) surface and the Mn subsurface, where the oxidation states of the Mn atoms are found to be +4.
Figure 12 shows the Mn-O average bond length: Mn₃+ changes its valence to Mn 4 + when the graphene sheet is present, and the average Mn-O bond length in z-direction is reduced. In comparison, Mn 4 + atoms in the subsurface change their valence to Mn 3., and the average Mn-O 15 bond length is …
Figure 13 shows the metal-graphene binding energy (eV) versus displacement from divacancy (A).
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A cathode comprising: a metal oxide spinel film comprising LiM x Mn₂- xO 4, and a graphene film, the graphene film disposed on a surface of the metal oxide film, wherein M is selected from a group comprising Li, Co, Ni, Al, Y, Ti, and Zn and X is any real number greater than or equal to zero and less than or equal to two and wherein the cathode is configured to form a solid electrolyte interphase layer disposed on the graphene film when the cathode is contacted with an electrolyte. Previously presented
The cathode of claim 1, wherein the metal oxide spinel comprises LiMn₂ 04. Previously presented
The cathode of claim 1, wherein the metal oxide spinel further comprises Co, Ni, Al, Y, Ti, or Zn. Previously presented
The cathode of claim 1, wherein M is selected from a group comprising Li, Co, Ni, and Zn. Previously presented
The cathode of claim 1, wherein the metal oxide spinel film has a thickness greater than or equal to 100 nm and less than or equal to 150 nm. Previously presented
The cathode of claim 1, wherein the graphene film comprises a substantially monolayer graphene film. Previously presented
The cathode of claim 1, wherein the graphene film comprises less than or equal to 20 % double-layer graphene islands. Previously presented
The cathode of claim 1, wherein the graphene film is substantially free of vacancy defects. Previously presented
The cathode of claim 1, wherein the metal oxide spinel film comprises a plurality of manganese atoms having a bulk oxidation state and a plurality of manganese atoms having a surface oxidation state, wherein the surface oxidation state is greater than the bulk oxidation state. Previously presented
The cathode of claim 1, wherein the cathode further comprises the solid electrolyte interphase layer disposed on the graphene film and wherein the solid electrolyte interphase layer comprises lithium carbonate. Previously presented
An electrochemical cell comprising the cathode of claim 1, an anode, and an electrolyte. Previously presented
A method for preparing a cathode, the method comprising: (a) obtaining the metal oxide spinel film of claim 1; (b) obtaining a graphene film; and (c) transferring the graphene film onto a surface of the metal oxide spinel film. Previously presented
9-10. Canceled
Canceled
Canceled
Canceled
24-49. Canceled
Canceled
Layer stacks claimed or described, ordered top of device to substrate.
graphene-coated LiMxMn₂-xO₄ spinel cathode
electrochemical cell (lithium-ion battery)
Materials described outside the worked examples.
lithium manganese oxide spinel (LiMxMn₂-xO₄)
LiMxMn₂-xO₄
graphene film
solid electrolyte interphase layer
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
Figure 2A shows an SEM image of spinel LMO thin films.
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
metal oxide spinel film thickness (claimed range) | 100–150 nm | LiMxMn₂-xO₄ |
solid electrolyte interphase film thickness (claimed upper bound) | ≤ 100 nm |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 10,749,170Patent drawings and their descriptions. Click a drawing to enlarge it.
Figure 1 shows a schematic illustration of the sample preparation process. Graphene may be grown using chemical vapor deposition (CVD) on copper foil and then transferred on top of 15 spinel LiMn 2 0 4 (LMO) thin fi lms using a poly(methyl methacrylate) (PMMA) transfer method. The thin film LMO may …
Figure 2A shows an SEM image of spinel LMO thin films.
Figure 2B shows a grazing incidence X-ray diffraction of LMO thin fi lms showing a spinel crystal structure. 20
Figure 2C shows an SEM image of graphene transferred onto a LMO thin film; the graphene is indicated by arrows.
Figure 2D shows a Raman spectrum of graphene-coated LMO obtained using a Raman laser wavelength of 514 nm. The shape of the 2 D (2700 cm 1) peak and the ratio of 2 D to G (1580 cm⁻¹) intensity are characteristic of single-layer graphene. The high-intensity peak at-620 25 cm⁻¹ is attributed to the …
Figure 3A shows capacity retention of LMO and graphene-LMO thin films versus cycle 30 number for LMO and graphene-coated LMO cathodes in lithium half cells at 100 mA/cm 3.
Figures 3B shows capacity retention versus cycle number for uncoated and graphene- coated LMO cathodes in graphite/LMO full cells at various cu rr ent rates (100-500 mA/cm 3).
Figure 4A shows a cyclic voltammetry curve of LMO thin film vs. lithium.
Figure 4B shows a voltage-capacity curve of LMO thin film vs. lithium. 5
Figure 4C shows a cyclic voltammetry curveof graphene-coated LMO thin films vs. lithium.
Figure 4D shows a voltage-capacity curve of graphene-coated LMO thin fi lms vs. lithium.
Figure 4E shows a voltage-capacity curve of uncoated LMO thin films vs. graphite. 10
Figure 4F shows a voltage-capacity curves of graphene-coated LMO thin films vs. graphite.
Figure 4G shows volumetric capacity of LMO and graphene-coated LMO thin fi lms vs. lithium.
Figure 4 H shows volumetric capacity of LMO and graphene-coated LMO thin fi lms vs. 15 graphite.
Figure 5A shows XPS depth profiling of the Mn 2P peaks for graphene-coated LMO cathodes after 750 lithiation/delithiation cycles.
Figure 5B shows XPS depth pro fi ling of the Mn 2P peaks for uncoated LMO cathodes after 350 lithiation/delithiation cycles. 20
Figure 5C shows no rm alized Li 1S peaks for graphene-coated LMO after 750 lithiation/delithiation cycles.
Figure 5D shows no rm alized Li 1S peaks for uncoated LMO after 350 lithiation/delithiation cycles.
Figure 5E shows the variation of Mn 2P (3/2) peak intensity versus depth for graphene- 25 coated LMO and uncoated LMO after lithiation/delithiation in a lithium half cell (3.5 to 4.4 V) for 750 and 350 cycles, respectively.
Figure 5F shows the variation of Mn 2P (3/2) peak intensity versus depth for graphene-coated LMO and uncoated LMO after lithiation/delithiation in graphite/LMO full cells (2 to 4.4 V) for 100 cycles. 30
Figure 6A shows the effect of graphene on SE I formation of LMO cathodes by XPS depth pro fi les of O 1S peak for graphene-coated LMO after cycling.
Figure 6B shows the effect of graphene on SE I fo rm ation of LMO cathodes by XPS depth profiles of O 15 peak for uncoated LMO after cycling.
Figure 6C shows bright-field cross-sectional STEM images of graphene-coated LMO after cycling. 5
Figure 6D shows bright-field cross-sectional STEM images of uncoated LMO after cycling.
Figure 6E shows cross-sectional HRTEM images of graphene-coated LMO after cycling.
Figure 6F shows cross-sectional HRTEM images of uncoated LMO after cycling.
Figure 7A shows a grazing incidence x-ray diffraction measurement of the LMO and graphene-coated 10 LMO films after cycling.
Figure 7B shows an SEM image of the LMO cathode after 350 cycles.
Figure 7C shows a Raman spectrum of graphene-coated LMO after 750 cycles. The sharp peak to the left of the 2D peak (~ 2400 cm-) is due to ambient nitrogen.
Figure 7D shows an SEM image of the graphene-coated LMO after 750 cycles. 15
Figure 8A illustrates a diffusion energy barrier through DV(5-8-5) in graphene for Mn approaching the graphene sheet. The inset shows the structure of the DV in the closed configuration with Mn near the graphene sheet (0.6 A away from graphene).
Figure 8B illustrates a Mn potential energy profile for Mn within the DV. The inset shows the structure of the DV in the open configuration. The insets are truncations near the DV 20 of the K e kule 156-atom graphene flake model. For reference, the calculated binding energies for Li and Mn for the …
Figure 9A illustrates a LMO (001) surface in thin film LMO electrodes for a graphene patch adsorbed perpendicular (90 0) to the surface. 25
Figure 9B illustrates a LMO (001) surface in thin film LMO electrodes for a graphene patch adsorbed at 45 0 relative to the surface.
Figure 9C illustrates a LMO (001) surface in thin film LMO electrodes for a graphene patch adsorbed parallel (0 0) relative to the surface.
Figure 10 B illustrates the effect of the 0/45/90 graphene bound to (001) LMO surface (Mn 4 +) and subsurface (Mn.'+ x-). The Fermi level is set as zero in the DOS plots. 5
Figure 11 A shows the chemical structure of a graphene patch adsorbed perpendicularly on a "Long" slab of a (001) Li i 6 Mn 32 O 6 4 surface.
Figure 11B shows the chemical structure of a graphene patch adsorbed perpendicularly on a "Wide" slab of a (001) Li 16 Mn 32 O 6 4 surface.
Figure 11 C shows the majority-spin channel of the Mn 3d projected density of states 10 (DOS) of the 90 0 GP/Li 6 Mn₃₂ O₆₄ (001) surface and the Mn subsurface, where the oxidation states of the Mn atoms are found to be +4.
Figure 12 shows the Mn-O average bond length: Mn₃+ changes its valence to Mn 4 + when the graphene sheet is present, and the average Mn-O bond length in z-direction is reduced. In comparison, Mn 4 + atoms in the subsurface change their valence to Mn 3., and the average Mn-O 15 bond length is …
Figure 13 shows the metal-graphene binding energy (eV) versus displacement from divacancy (A).
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A cathode comprising: a metal oxide spinel film comprising LiM x Mn₂- xO 4, and a graphene film, the graphene film disposed on a surface of the metal oxide film, wherein M is selected from a group comprising Li, Co, Ni, Al, Y, Ti, and Zn and X is any real number greater than or equal to zero and less than or equal to two and wherein the cathode is configured to form a solid electrolyte interphase layer disposed on the graphene film when the cathode is contacted with an electrolyte. Previously presented
The cathode of claim 1, wherein the metal oxide spinel comprises LiMn₂ 04. Previously presented
The cathode of claim 1, wherein the metal oxide spinel further comprises Co, Ni, Al, Y, Ti, or Zn. Previously presented
The cathode of claim 1, wherein M is selected from a group comprising Li, Co, Ni, and Zn. Previously presented
The cathode of claim 1, wherein the metal oxide spinel film has a thickness greater than or equal to 100 nm and less than or equal to 150 nm. Previously presented
The cathode of claim 1, wherein the graphene film comprises a substantially monolayer graphene film. Previously presented
The cathode of claim 1, wherein the graphene film comprises less than or equal to 20 % double-layer graphene islands. Previously presented
The cathode of claim 1, wherein the graphene film is substantially free of vacancy defects. Previously presented
The cathode of claim 1, wherein the metal oxide spinel film comprises a plurality of manganese atoms having a bulk oxidation state and a plurality of manganese atoms having a surface oxidation state, wherein the surface oxidation state is greater than the bulk oxidation state. Previously presented
The cathode of claim 1, wherein the cathode further comprises the solid electrolyte interphase layer disposed on the graphene film and wherein the solid electrolyte interphase layer comprises lithium carbonate. Previously presented
An electrochemical cell comprising the cathode of claim 1, an anode, and an electrolyte. Previously presented
A method for preparing a cathode, the method comprising: (a) obtaining the metal oxide spinel film of claim 1; (b) obtaining a graphene film; and (c) transferring the graphene film onto a surface of the metal oxide spinel film. Previously presented
9-10. Canceled
Canceled
Canceled
Canceled
24-49. Canceled
Canceled
Layer stacks claimed or described, ordered top of device to substrate.
graphene-coated LiMxMn₂-xO₄ spinel cathode
electrochemical cell (lithium-ion battery)
Materials described outside the worked examples.
lithium manganese oxide spinel (LiMxMn₂-xO₄)
LiMxMn₂-xO₄
graphene film
solid electrolyte interphase layer
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
Figure 2A shows an SEM image of spinel LMO thin films.
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
metal oxide spinel film thickness (claimed range) | 100–150 nm | LiMxMn₂-xO₄ |
solid electrolyte interphase film thickness (claimed upper bound) | ≤ 100 nm |
Related documents with shared materials, methods, properties, or citations.
LiMn₂O₄
lithium carbonate solid electrolyte interphase layer
Li₂CO₃
lithium anode
Li
graphite anode
electrolyte comprising lithium salt and organic carbonate solvent
1 M LiClO₄ in 1:1 ethylene carbonate:dimethyl carbonate
monolayer graphene film (CVD-grown)
Figure 2C shows an SEM image of graphene transferred onto a LMO thin film; the graphene is indicated by arrows.
Figure 2D shows a Raman spectrum of graphene-coated LMO obtained using a Raman laser wavelength of 514 nm. The shape of the 2 D (2700 cm 1) peak and the ratio of 2 D to G (1580 cm⁻¹) intensity are characteristic of single-layer graphene. The high-intensity peak at-620 25 cm⁻¹ is attributed to the …
Figure 5A shows XPS depth profiling of the Mn 2P peaks for graphene-coated LMO cathodes after 750 lithiation/delithiation cycles.
Figure 5B shows XPS depth pro fi ling of the Mn 2P peaks for uncoated LMO cathodes after 350 lithiation/delithiation cycles. 20
Figure 6A shows the effect of graphene on SE I formation of LMO cathodes by XPS depth pro fi les of O 1S peak for graphene-coated LMO after cycling.
Figure 6B shows the effect of graphene on SE I fo rm ation of LMO cathodes by XPS depth profiles of O 15 peak for uncoated LMO after cycling.
Figure 6C shows bright-field cross-sectional STEM images of graphene-coated LMO after cycling. 5
Figure 6D shows bright-field cross-sectional STEM images of uncoated LMO after cycling.
Figure 6E shows cross-sectional HRTEM images of graphene-coated LMO after cycling.
Figure 6F shows cross-sectional HRTEM images of uncoated LMO after cycling.
Figure 7B shows an SEM image of the LMO cathode after 350 cycles.
Figure 7C shows a Raman spectrum of graphene-coated LMO after 750 cycles. The sharp peak to the left of the 2D peak (~ 2400 cm-) is due to ambient nitrogen.
Figure 7D shows an SEM image of the graphene-coated LMO after 750 cycles. 15
Figure 10 B illustrates the effect of the 0/45/90 graphene bound to (001) LMO surface (Mn 4 +) and subsurface (Mn.'+ x-). The Fermi level is set as zero in the DOS plots. 5
Figure 11 C shows the majority-spin channel of the Mn 3d projected density of states 10 (DOS) of the 90 0 GP/Li 6 Mn₃₂ O₆₄ (001) surface and the Mn subsurface, where the oxidation states of the Mn atoms are found to be +4.
Voltage | 2–4.4 V | — |
Voltage | 3.5–4.4 V | — |
Pressure | 30–50 mTorr | — |
Voltage | ≤ 3 V | — |
Thickness | ≤ 0.23 nm | — |
Thickness | 1–2 cm | — |
Thickness | ≤ 2 cm | — |
Thickness | ≥ 1 cm | — |
LiMn₂O₄
lithium carbonate solid electrolyte interphase layer
Li₂CO₃
lithium anode
Li
graphite anode
electrolyte comprising lithium salt and organic carbonate solvent
1 M LiClO₄ in 1:1 ethylene carbonate:dimethyl carbonate
monolayer graphene film (CVD-grown)
Figure 2C shows an SEM image of graphene transferred onto a LMO thin film; the graphene is indicated by arrows.
Figure 2D shows a Raman spectrum of graphene-coated LMO obtained using a Raman laser wavelength of 514 nm. The shape of the 2 D (2700 cm 1) peak and the ratio of 2 D to G (1580 cm⁻¹) intensity are characteristic of single-layer graphene. The high-intensity peak at-620 25 cm⁻¹ is attributed to the …
Figure 5A shows XPS depth profiling of the Mn 2P peaks for graphene-coated LMO cathodes after 750 lithiation/delithiation cycles.
Figure 5B shows XPS depth pro fi ling of the Mn 2P peaks for uncoated LMO cathodes after 350 lithiation/delithiation cycles. 20
Figure 6A shows the effect of graphene on SE I formation of LMO cathodes by XPS depth pro fi les of O 1S peak for graphene-coated LMO after cycling.
Figure 6B shows the effect of graphene on SE I fo rm ation of LMO cathodes by XPS depth profiles of O 15 peak for uncoated LMO after cycling.
Figure 6C shows bright-field cross-sectional STEM images of graphene-coated LMO after cycling. 5
Figure 6D shows bright-field cross-sectional STEM images of uncoated LMO after cycling.
Figure 6E shows cross-sectional HRTEM images of graphene-coated LMO after cycling.
Figure 6F shows cross-sectional HRTEM images of uncoated LMO after cycling.
Figure 7B shows an SEM image of the LMO cathode after 350 cycles.
Figure 7C shows a Raman spectrum of graphene-coated LMO after 750 cycles. The sharp peak to the left of the 2D peak (~ 2400 cm-) is due to ambient nitrogen.
Figure 7D shows an SEM image of the graphene-coated LMO after 750 cycles. 15
Figure 10 B illustrates the effect of the 0/45/90 graphene bound to (001) LMO surface (Mn 4 +) and subsurface (Mn.'+ x-). The Fermi level is set as zero in the DOS plots. 5
Figure 11 C shows the majority-spin channel of the Mn 3d projected density of states 10 (DOS) of the 90 0 GP/Li 6 Mn₃₂ O₆₄ (001) surface and the Mn subsurface, where the oxidation states of the Mn atoms are found to be +4.
Voltage | 2–4.4 V | — |
Voltage | 3.5–4.4 V | — |
Pressure | 30–50 mTorr | — |
Voltage | ≤ 3 V | — |
Thickness | ≤ 0.23 nm | — |
Thickness | 1–2 cm | — |
Thickness | ≤ 2 cm | — |
Thickness | ≥ 1 cm | — |
LiMn₂O₄
lithium carbonate solid electrolyte interphase layer
Li₂CO₃
lithium anode
Li
graphite anode
electrolyte comprising lithium salt and organic carbonate solvent
1 M LiClO₄ in 1:1 ethylene carbonate:dimethyl carbonate
monolayer graphene film (CVD-grown)
Figure 2C shows an SEM image of graphene transferred onto a LMO thin film; the graphene is indicated by arrows.
Figure 2D shows a Raman spectrum of graphene-coated LMO obtained using a Raman laser wavelength of 514 nm. The shape of the 2 D (2700 cm 1) peak and the ratio of 2 D to G (1580 cm⁻¹) intensity are characteristic of single-layer graphene. The high-intensity peak at-620 25 cm⁻¹ is attributed to the …
Figure 5A shows XPS depth profiling of the Mn 2P peaks for graphene-coated LMO cathodes after 750 lithiation/delithiation cycles.
Figure 5B shows XPS depth pro fi ling of the Mn 2P peaks for uncoated LMO cathodes after 350 lithiation/delithiation cycles. 20
Figure 6A shows the effect of graphene on SE I formation of LMO cathodes by XPS depth pro fi les of O 1S peak for graphene-coated LMO after cycling.
Figure 6B shows the effect of graphene on SE I fo rm ation of LMO cathodes by XPS depth profiles of O 15 peak for uncoated LMO after cycling.
Figure 6C shows bright-field cross-sectional STEM images of graphene-coated LMO after cycling. 5
Figure 6D shows bright-field cross-sectional STEM images of uncoated LMO after cycling.
Figure 6E shows cross-sectional HRTEM images of graphene-coated LMO after cycling.
Figure 6F shows cross-sectional HRTEM images of uncoated LMO after cycling.
Figure 7B shows an SEM image of the LMO cathode after 350 cycles.
Figure 7C shows a Raman spectrum of graphene-coated LMO after 750 cycles. The sharp peak to the left of the 2D peak (~ 2400 cm-) is due to ambient nitrogen.
Figure 7D shows an SEM image of the graphene-coated LMO after 750 cycles. 15
Figure 10 B illustrates the effect of the 0/45/90 graphene bound to (001) LMO surface (Mn 4 +) and subsurface (Mn.'+ x-). The Fermi level is set as zero in the DOS plots. 5
Figure 11 C shows the majority-spin channel of the Mn 3d projected density of states 10 (DOS) of the 90 0 GP/Li 6 Mn₃₂ O₆₄ (001) surface and the Mn subsurface, where the oxidation states of the Mn atoms are found to be +4.
Voltage | 2–4.4 V | — |
Voltage | 3.5–4.4 V | — |
Pressure | 30–50 mTorr | — |
Voltage | ≤ 3 V | — |
Thickness | ≤ 0.23 nm | — |
Thickness | 1–2 cm | — |
Thickness | ≤ 2 cm | — |
Thickness | ≥ 1 cm | — |
LiMn₂O₄
lithium carbonate solid electrolyte interphase layer
Li₂CO₃
lithium anode
Li
graphite anode
electrolyte comprising lithium salt and organic carbonate solvent
1 M LiClO₄ in 1:1 ethylene carbonate:dimethyl carbonate
monolayer graphene film (CVD-grown)
Figure 2C shows an SEM image of graphene transferred onto a LMO thin film; the graphene is indicated by arrows.
Figure 2D shows a Raman spectrum of graphene-coated LMO obtained using a Raman laser wavelength of 514 nm. The shape of the 2 D (2700 cm 1) peak and the ratio of 2 D to G (1580 cm⁻¹) intensity are characteristic of single-layer graphene. The high-intensity peak at-620 25 cm⁻¹ is attributed to the …
Figure 5A shows XPS depth profiling of the Mn 2P peaks for graphene-coated LMO cathodes after 750 lithiation/delithiation cycles.
Figure 5B shows XPS depth pro fi ling of the Mn 2P peaks for uncoated LMO cathodes after 350 lithiation/delithiation cycles. 20
Figure 6A shows the effect of graphene on SE I formation of LMO cathodes by XPS depth pro fi les of O 1S peak for graphene-coated LMO after cycling.
Figure 6B shows the effect of graphene on SE I fo rm ation of LMO cathodes by XPS depth profiles of O 15 peak for uncoated LMO after cycling.
Figure 6C shows bright-field cross-sectional STEM images of graphene-coated LMO after cycling. 5
Figure 6D shows bright-field cross-sectional STEM images of uncoated LMO after cycling.
Figure 6E shows cross-sectional HRTEM images of graphene-coated LMO after cycling.
Figure 6F shows cross-sectional HRTEM images of uncoated LMO after cycling.
Figure 7B shows an SEM image of the LMO cathode after 350 cycles.
Figure 7C shows a Raman spectrum of graphene-coated LMO after 750 cycles. The sharp peak to the left of the 2D peak (~ 2400 cm-) is due to ambient nitrogen.
Figure 7D shows an SEM image of the graphene-coated LMO after 750 cycles. 15
Figure 10 B illustrates the effect of the 0/45/90 graphene bound to (001) LMO surface (Mn 4 +) and subsurface (Mn.'+ x-). The Fermi level is set as zero in the DOS plots. 5
Figure 11 C shows the majority-spin channel of the Mn 3d projected density of states 10 (DOS) of the 90 0 GP/Li 6 Mn₃₂ O₆₄ (001) surface and the Mn subsurface, where the oxidation states of the Mn atoms are found to be +4.
Voltage | 2–4.4 V | — |
Voltage | 3.5–4.4 V | — |
Pressure | 30–50 mTorr | — |
Voltage | ≤ 3 V | — |
Thickness | ≤ 0.23 nm | — |
Thickness | 1–2 cm | — |
Thickness | ≤ 2 cm | — |
Thickness | ≥ 1 cm | — |