NOVELTY - The battery (101) has an electrode assembly (10) including a positive electrode (11) and a negative electrode (12). A case accommodates the electrode assembly. A negative terminal (20) is electrically connected to the negative electrode. A cap plate (31) is electrically connected to the positive electrode. An electron donor (62) is electrically connected to the terminal, where the donor is made of material having higher reactivity than material of the terminal. A positive terminal (21) is electrically connected to the positive electrode of the electrode assembly.    USE - Rechargeable battery e.g. prismatic or hexahedral shaped lithium ion rechargeable battery such as low-capacity lithium ion rechargeable battery used in a small portable electronic device e.g. mobile phone, laptop computer and camcorder, and large-capacity lithium ion rechargeable battery used as power supply for driving a motor of a hybrid electric vehicle. Can also be used for a lithium polymer battery and a cylindrical shaped battery.    ADVANTAGE - The battery allows electrons to be moved to the cap plate such that a number of the electrons in the negative terminal can not decrease, so that corrosion in the negative terminal by decrease of the number of the electrons in the negative terminal can be reduced and prevented and not oxidation of the negative terminal can be prevented, thus reducing deterioration of performance of the battery.    DETAILED DESCRIPTION - The material is selected from a group consisting of magnesium, sodium, zinc, iron, cobalt and lead. The terminal is made of aluminum or copper. The electron donor is a sacrificial electrode that corrodes at higher rate than the former terminal.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of a rechargeable battery.    Electrode assembly (10)    Positive electrode (11)    Negative electrode (12)    Negative terminal (20)    Positive terminal (21)    Cap assembly (30)    Cap plate (31)    Electron donor (62)    Rechargeable battery (101)