NOVELTY - The storing device (20) has the primary switches and secondary switches, each are coupled between one of the rechargeable battery modules (RBT1-RBTn) and a high-voltage terminal (202) or a low-voltage terminal (204) respectively for turning on or off electrical connection between the battery module and the high or low-voltage terminal according to a control command. The tertiary switches are coupled between two of battery modules for turning on or off connection between the two battery modules. A control module (206) outputs the control command to control switches.    USE - Electricity storing device of electronic device (claimed) or equipment requiring independent power, such as mobile phone, personal digital assistant (PDA), electronic book, portable computer, and electric car.    ADVANTAGE - Since all of the rechargeable battery modules can be easily replaced, even if one rechargeable battery module fails, the user only needs to replace the rechargeable battery module, where the replacing operation is only a simple plugging operation and does not require special equipments or steps, which significantly enhances convenience and avoids waste of resources when a rechargeable battery is realized by the electricity storing device. Each rechargeable battery module operates in parallel, which can avoid the risk of one rechargeable battery module draining too much current and thus being burnt when the electricity storing device performs charging operations. The voltages across each rechargeable battery module are the same when the rechargeable battery modules are charged in parallel, so as to ensure charging efficiencies for each rechargeable battery module at approximate levels. Thus, protecting circuits between the rechargeable battery modules can be omitted, or replaced with protecting circuits of low cost to achieve protecting effect. The main feature of the electricity storing device is flexible operations, which can meet all kinds of different power outputting or storing requirements, and are not limited to rechargeable battery.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for electronic device.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram of an electricity storing device.    Electricity storing device (20)    High-voltage terminal (202)    Low-voltage terminal (204)    Control module (206)    Rechargeable battery modules (RBT-1-RBT-n)