NOVELTY - The battery pack (100) has multiple temperature sensors (120) arranged adjacent to battery cells (111). A temperature data generating unit (130) detects battery temperatures from the temperature sensors and generates battery temperature data including temperature values corresponding to the battery temperatures. A control unit (140) determines whether each of the temperature sensors is defective or not based on the battery temperature data, and controls a battery module (110) based on temperature values corresponding to temperature sensors determined not to be defective.    USE - Battery pack for secondary or rechargeable batteries of an energy storage apparatus (claimed) in electronic devices at a house or factory. Uses include but are not limited to smart phones, laptop computers, personal digital assistants, vehicles such as hybrid vehicles and electric vehicles e.g. electric bicycles and electric motorcycles, and energy storage systems.    ADVANTAGE - The battery pack utilizes a power converting unit to stop operating and minimize or reduce power consumed by a power conversion apparatus such as converter or the rectifier circuit when power is not generated by a power generation system and when charge and discharge operations with respect to the battery pack are not performed. The inverter ensures restriction of voltage fluctuation range, improvement of a power-factor, elimination of a direct current (DC) component and protection from transient phenomena, thus preventing a worker operating at a power line of a grid from being shocked by power from the power generation system or the battery pack by operating an energy storage apparatus in a stand alone system.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for the following:    (1) a method for managing a battery pack    (2) an energy storage apparatus.    DESCRIPTION OF DRAWING(S) - The drawing shows a circuit diagram of a battery pack.    Battery pack (100)    Battery module (110)    Battery cells (111)    Temperature sensors (120)    Temperature data generating unit (130)    Control unit (140)