Abstract: A controller in a charging control system controls a charger to heat a battery at a low temperature by pulse charging and discharging up to a desired temperature and then moves to a normal charging mode. The controller calculates an ion concentration of an active material at electrode portions of the battery on the basis of the temperature data and the electric current data obtained, switch the pulse charging and discharging between a charging mode and a discharging mode on the basis of a pulse width when the ion concentration reaches a threshold.

Abstract: Disclosed is an anode material comprising a metal core layer capable of repetitive lithium intercalation/deintercalation; an amorphous carbon layer coated on the surface of the metal core layer, and a crystalline carbon layer coated on the amorphous carbon layer. The anode material not only maintains a high charge/discharge capacity, which is an advantage of a metal-based anode material, but also inhibits changes in the volume of a metal core layer caused by repetitive lithium intercalation/deintercalation in virtue of an amorphous carbon layer and a crystalline carbon layer, thereby improving the cycle life characteristics of cells.

Abstract: A controller in a charging control system controls a charger to heat a battery at a low temperature by pulse charging and discharging up to a desired temperature and then moves to a normal charging mode. The controller calculates an ion concentration of an active material at electrode portions of the battery on the basis of the temperature data and the electric current data obtained, switch the pulse charging and discharging between a charging mode and a discharging mode on the basis of a pulse width when the ion concentration reaches a threshold.

Abstract: Disclosed is an electrode active material comprising: a core layer capable of repeating lithium intercalation/deintercalation; an amorphous carbon layer; and a crystalline carbon layer, successively, wherein the core layer comprises at least two core particles. A secondary battery comprising the same electrode active material is also disclosed. The electrode active material can inhibit variations in volume of the core layer that may occur during repeated charge/discharge cycles, since the core layer comprising at least two core particles, each core particle having an increased area that is in contact with the carbon layer coated thereon. Therefore, the battery using the electrode active material can provide improved cycle life characteristics.

Abstract: The present invention provides a method for preparing spherical carbon comprising step of heat-treating a mixture of a carbon precursor and dispersion media, a spherical non-graphitizable carbon using the same, and a method for preparing spherical artificial graphite.

Abstract: The present invention provides a method for preparing spherical carbon comprising step of heat-treating a mixture of a carbon precursor and dispersion media, a spherical non-graphitizable carbon using the same, and a method for preparing spherical artificial graphite.

Abstract: The present invention provides a method for preparing spherical carbon comprising step of heat-treating a mixture of a carbon precursor and dispersion media, a spherical non-graphitizable carbon using the same, and a method for preparing spherical artificial graphite.

Abstract: Disclosed is an electrode active material comprising: a core layer capable of repeating lithium intercalation/deintercalation; an amorphous carbon layer; and a crystalline carbon layer, successively, wherein the crystalline carbon layer comprises sheet-like carbon layer units, and the c-axis direction of the sheet-like carbon layer units is perpendicular to a tangent direction of the electrode active material particle. A secondary battery comprising the same electrode active material is also disclosed.

Abstract: Disclosed is an electrode active material comprising: a core layer capable of repeating lithium intercalation/deintercalation; an amorphous carbon layer; and a crystalline carbon layer, successively, wherein the core layer comprises at least two core particles. A secondary battery comprising the same electrode active material is also disclosed. The electrode active material can inhibit variations in volume of the core layer that may occur during repeated charge/discharge cycles, since the core layer comprising at least two core particles, each core particle having an increased area that is in contact with the carbon layer coated thereon. Therefore, the battery using the electrode active material can provide improved cycle life characteristics.

Abstract: Disclosed is an electrode active material comprising: a core layer capable of repeating lithium intercalation/deintercalation; an amorphous carbon layer; and a crystalline carbon layer, successively, wherein the crystalline carbon layer comprises sheet-like carbon layer units and partially or totally comprises multilayer sheet-like carbon layer units. A secondary battery comprising the same electrode active material is also disclosed. The electrode active material can inhibit variations in volume of the core layer that may occur during repeated charge/discharge cycles, by virtue of the interstitial volumes formed by the multilayer sheet-like carbon layer units in the crystalline carbon layer. Therefore, the battery using the electrode active material can provide improved cycle life characteristics.

Abstract: The present invention provides a method for preparing spherical carbon comprising step of heat-treating a mixture of a carbon precursor and dispersion media, a spherical non-graphitizable carbon using the same, and a method for preparing spherical artificial graphite.