Abstract: A cooling and heating system includes a battery pack, a temperature sensing module, a semiconductor cooling chip, a current adjustment module, and a control module. The control module controls the current adjustment module to make a current flowed into the semiconductor cooling chip in a first direction, when a temperature of the battery pack is greater than a first reference temperature; and controls the current adjustment module to make the current flowed into the semiconductor cooling chip in a second direction opposite to the first direction, when the temperature of the battery pack is less than a second reference temperature. The battery pack is cooled by the semiconductor cooling chip, when the current flowed into the semiconductor cooling chip is in the first direction. The battery pack is heated by the semiconductor cooling chip, when the current flowed into the semiconductor cooling chip is in the second direction.