BATTERY PACK

Discussed is a battery pack, the temperature of which is maintained within a certain range by a heating component or a heat dissipating component attached thereto. The battery pack includes an upper end cover provided above cylindrical cells to protect an inside of the battery pack, a first metal panel positioned below the upper end cover and jointed to the upper portion of the cylindrical cells, a second metal panel jointed to a lower portion of the cylindrical cells, a holder configured to surround and fix an outer side surface of the entire cylindrical cells and the lower portion of the second metal panel, and a lower end cover positioned below the second metal panel and the holder to form a lower end portion of the battery pack.