摘要:
A supercapacitor comprising a two electrodes, a porous separator disposed between the two electrodes, and an ionic liquid electrolyte in physical contact with the two electrodes, wherein at least one of the two electrodes comprises a meso-porous structure being formed of a plurality of nano graphene platelets and multiple pores having a pore size in the range of 2 nm and 25 nm, wherein the graphene platelets are not spacer-modified or surface-modified platelets. Preferably, the graphene platelets are curved, not flat-shaped. The pores are accessible to ionic liquid molecules, enabling the formation of large amounts of electric double layer charges in a supercapacitor, which exhibits an exceptionally high specific capacitance and high energy density.
摘要:
A supercapacitor comprising a two electrodes, a porous separator disposed between the two electrodes, and an ionic liquid electrolyte in physical contact with the two electrodes, wherein at least one of the two electrodes comprises a meso-porous structure being formed of a plurality of nano graphene platelets and multiple pores having a pore size in the range of 2 nm and 25 nm, wherein the graphene platelets are not spacer-modified or surface-modified platelets. Preferably, the graphene platelets are curved, not flat-shaped. The pores are accessible to ionic liquid molecules, enabling the formation of large amounts of electric double layer charges in a supercapacitor, which exhibits an exceptionally high specific capacitance and high energy density.
摘要:
A spacer-modified nano graphene platelet electrode, comprising: (a) multiple nano graphene platelets or sheets having an average thickness smaller than 10 nm; and (b) discrete, non-metallic nano-scaled particles that are disposed between two graphene platelets or sheets to serve as a spacer. In such a spacer-modified graphene electrode, large amounts of electrolyte-accessible pores are formed, enabling the formation of large amounts of electric double layer charges in a supercapacitor, which exhibits an exceptionally high specific capacitance.
摘要:
A spacer-modified nano graphene platelet electrode, comprising: (a) multiple nano graphene platelets or sheets having an average thickness smaller than 10 nm; and (b) discrete, non-metallic nano-scaled particles that are disposed between two graphene platelets or sheets to serve as a spacer. In such a spacer-modified graphene electrode, large amounts of electrolyte-accessible pores are formed, enabling the formation of large amounts of electric double layer charges in a supercapacitor, which exhibits an exceptionally high specific capacitance.
摘要:
A flexible, asymmetric electrochemical cell comprising: (A) A sheet of graphene paper as first electrode comprising nano graphene platelets having a platelet thickness less than 1 nm, wherein the first electrode has electrolyte-accessible pores; (B) A thin-film or paper-like first separator and electrolyte; and (C) A thin-film or paper-like second electrode which is different in composition than the first electrode; wherein the separator is sandwiched between the first and second electrode to form a flexible laminate configuration. The asymmetric supercapacitor cells with different NGP-based electrodes exhibit an exceptionally high capacitance, specific energy, and stable and long cycle life.
摘要:
A flexible, asymmetric electrochemical cell comprising: (A) A sheet of graphene paper as first electrode comprising nano graphene platelets having a platelet thickness less than 1 nm, wherein the first electrode has electrolyte-accessible pores; (B) A thin-film or paper-like first separator and electrolyte; and (C) A thin-film or paper-like second electrode which is different in composition than the first electrode; wherein the separator is sandwiched between the first and second electrode to form a flexible laminate configuration. The asymmetric supercapacitor cells with different NGP-based electrodes exhibit an exceptionally high capacitance, specific energy, and stable and long cycle life.
摘要:
A surface-enabled, metal ion-exchanging battery device comprising a cathode, an anode, a porous separator, and a metal ion-containing electrolyte, wherein the metal ion is selected from (A) non-Li alkali metals; (B) alkaline-earth metals; (C) transition metals; (D) other metals such as aluminum (Al); or (E) a combination thereof; and wherein at least one of the electrodes contains therein a metal ion source prior to the first charge or discharge cycle of the device and at least the cathode comprises a functional material or nano-structured material having a metal ion-capturing functional group or metal ion-storing surface in direct contact with said electrolyte, and wherein the operation of the battery device does not involve the introduction of oxygen from outside the device and does not involve the formation of a metal oxide, metal sulfide, metal selenide, metal telluride, metal hydroxide, or metal-halogen compound. This energy storage device has a power density significantly higher than that of a lithium-ion battery and an energy density dramatically higher than that of a supercapacitor.
摘要:
A surface-enabled, metal ion-exchanging battery device comprising a cathode, an anode, a porous separator, and a metal ion-containing electrolyte, wherein the metal ion is selected from (A) non-Li alkali metals; (B) alkaline-earth metals; (C) transition metals; (D) other metals such as aluminum (Al); or (E) a combination thereof; and wherein at least one of the electrodes contains therein a metal ion source prior to the first charge or discharge cycle of the device and at least the cathode comprises a functional material or nano-structured material having a metal ion-capturing functional group or metal ion-storing surface in direct contact with said electrolyte, and wherein the operation of the battery device does not involve the introduction of oxygen from outside the device and does not involve the formation of a metal oxide, metal sulfide, metal selenide, metal telluride, metal hydroxide, or metal-halogen compound. This energy storage device has a power density significantly higher than that of a lithium-ion battery and an energy density dramatically higher than that of a supercapacitor.
摘要:
A specific embodiment of the present invention is a process for continuously producing a porous solid film of spacer-modified nano graphene platelets for supercapacitor electrode applications. This process comprises: (a) dissolving a precursor material in a solvent to form a precursor solution and dispersing multiple nano graphene platelets into the solution to form a suspension; (b) continuously delivering and forming the suspension into a layer of solid film composed of precursor material-coated graphene platelets overlapping one another, and removing the solvent from the solid film (e.g., analogous to a paper-making, mat-making, or web-making procedure); (c) continuously converting the precursor material into nodules bonded to surfaces of graphene platelets to form a porous solid film composed of spacer-modified graphene platelets; and (d) continuously collecting the porous solid film on a collector (e.g., a winding roller). The roll of porous solid film (mat, paper, or web) can then be cut into pieces for used as supercapacitor electrodes.
摘要:
A surface-modified nano graphene platelet (NGP), comprising: (a) a nano graphene platelet having a thickness smaller than 10 nm; and (b) discrete, non-continuous, and non-metallic bumps or nodules bonded to a surface of the graphene platelet to serve as a spacer. When multiple surface-modified NGP sheets are stacked together to form an electrode, large numbers of electrolyte-accessible pores are formed, enabling the formation of large amounts of double layer charges in a supercapacitor, which exhibits an exceptionally high specific capacitance.