The present invention relates to a carbonaceous material having a silicon element content of less than 200 ppm, a powder conductivity of 10.0 to 22.0 S/cm, a total amount of surface functional groups of 0.22 to 0.36 meq/g, and a pore volume of 0.10 to 0.20 cm.sup.3/g in terms of pores having a pore size of not less than 4 nm as measured by a BJH method.

Composites comprising an exfoliated graphite support material having a degree of graphitization g in an range of 50 to 93%, obtained by XRD Rietveld analysis, which is coated with ZnO nanoparticles. These composites are produced by three different methods: A) (syn) the method comprises the following consecutive steps: i) a Zn(II)salt is dissolved in a solvent ii) graphite and a base are added simultaneously iii) the mixture is stirred under impact of ultrasound iv) the solvent is removed from the suspension or B) (pre) the method comprises the following consecutive steps: i) graphite is suspended in a solvent and exfoliated via impact of ultrasound ii) a Zn(II)salt and a base are added simultaneously forming nano-ZnO particles iii) the mixture is stirred iv) the solvent is removed from the suspension or C) (post) the method comprises the following steps: i) a Zn(II)salt and a base are mixed in a solvent in a first reactor forming nano-ZnO particles ii) graphite is exfoliated via impact of ultrasound in a second reactor iii) both suspensions of i) and ii) are mixed together iv) after step iii) the solvent is removed from the suspension. These coated composites may be tempered in a further step and again coated and again tempered.

A mesoporous, nanocrystalline, metal oxide construct particularly suited for capacitive energy storage that has an architecture with short diffusion path lengths and large surface areas and a method for production are provided. Energy density is substantially increased without compromising the capacitive charge storage kinetics and electrode demonstrates long term cycling stability. Charge storage devices with electrodes using the construct can use three different charge storage mechanisms immersed in an electrolyte: (1) cations can be stored in a thin double layer at the electrode/electrolyte interface (non-faradaic mechanism); (2) cations can interact with the bulk of an electroactive material which then undergoes a redox reaction or phase change, as in conventional batteries (faradaic mechanism); or (3) cations can electrochemically adsorb onto the surface of a material through charge transfer processes (faradaic mechanism).

A mesoporous, nanocrystalline, metal oxide construct particularly suited for capacitive energy storage that has an architecture with short diffusion path lengths and large surface areas and a method for production are provided. Energy density is substantially increased without compromising the capacitive charge storage kinetics and electrode demonstrates long term cycling stability. Charge storage devices with electrodes using the construct can use three different charge storage mechanisms immersed in an electrolyte: (1) cations can be stored in a thin double layer at the electrode/electrolyte interface (non-faradaic mechanism); (2) cations can interact with the bulk of an electroactive material which then undergoes a redox reaction or phase change, as in conventional batteries (faradaic mechanism); or (3) cations can electrochemically adsorb onto the surface of a material through charge transfer processes (faradaic mechanism).

A laminated power storage device that includes a first end portion of a first current collector extends to an inside of an insulating adhesive portion relative to a first polarizable electrode layer, and a second end portion of a second current collector extends to an inside of the insulating adhesive portion relative to a second polarizable electrode layer.

A laminated power storage device that includes a first end portion of a first current collector extends to an inside of an insulating adhesive portion relative to a first polarizable electrode layer, and a second end portion of a second current collector extends to an inside of the insulating adhesive portion relative to a second polarizable electrode layer.

A method for fabricating an electrode includes: determining a thickness of an active layer; selecting lithium (Li) foil having a specified thickness; determining widths of one or more Li strips based on an active layer to Li layer weight ratio or volume ratio; laminating the active layer onto a conductive substrate; forming one or more grooves in the active layer exposing a bare surface of the conductive substrate; and pressing the one or more Li strips into the one or more grooves, wherein widths of the one or more grooves are slightly larger than the widths of the Li strips.

A boron-sulfur-codoped porous carbon material and a preparation method is disclosed. The boron-sulfur-codoped porous carbon material includes a porous carbon, and B and S doped in the surface and pores of the porous carbon; where B has a doping content of 5.56 wt.% to 7.85 wt.%, and S has a doping content of 0.90 wt.% to 1.55 wt.%. Test results of examples show that the boron-sulfur-codoped porous carbon material has high doping contents of B and S, and abundant pores; in a three-electrode system, the material shows a maximum specific capacitance of 168 F.Math.g.sup.- .sup.1 to 290.7 F.Math.g.sup.-1 at 0.5 A.Math.g.sup.-1; after the material is assembled into a symmetrical supercapacitor, the supercapacitor has an ultra-high energy density of 11.3 Wh.Math.kg.sup.-1 to 16.65 Wh.Math.kg.sup.-1 in a neutral electrolyte system, and has a capacitance retention rate of 97.09% to 100.67% after 10,000 life tests.

A boron-sulfur-codoped porous carbon material and a preparation method is disclosed. The boron-sulfur-codoped porous carbon material includes a porous carbon, and B and S doped in the surface and pores of the porous carbon; where B has a doping content of 5.56 wt.% to 7.85 wt.%, and S has a doping content of 0.90 wt.% to 1.55 wt.%. Test results of examples show that the boron-sulfur-codoped porous carbon material has high doping contents of B and S, and abundant pores; in a three-electrode system, the material shows a maximum specific capacitance of 168 F.Math.g.sup.- .sup.1 to 290.7 F.Math.g.sup.-1 at 0.5 A.Math.g.sup.-1; after the material is assembled into a symmetrical supercapacitor, the supercapacitor has an ultra-high energy density of 11.3 Wh.Math.kg.sup.-1 to 16.65 Wh.Math.kg.sup.-1 in a neutral electrolyte system, and has a capacitance retention rate of 97.09% to 100.67% after 10,000 life tests.

A porous silicon composite including: a porous silicon composite cluster comprising a porous silicon composite secondary particle and a second carbon flake on at least one surface of the porous silicon composite secondary particle; and a carbonaceous layer on the porous silicon composite cluster, the carbonaceous layer comprising amorphous carbon, wherein the porous silicon composite secondary particle comprises an aggregate of two or more silicon primary particles, the two or more silicon primary particles comprise silicon, a silicon suboxide of the formula SiO.sub.x, wherein 0<x<2 on a surface of the silicon, and a first carbon flake on at least one surface of the silicon suboxide, the silicon suboxide is in a form of a film, a matrix, or a combination thereof, and the first carbon flake and the second carbon flake are each independently present in a form of a film, particles, a matrix, or a combination thereof. Also a method of preparing the porous silicon composite, a carbon composite, an electrode, and a device, each including the porous silicon composite, and a lithium battery including the electrode.