SEALED BATTERY

PURPOSE:To improve the sealing performance and the liquid-leakage resistance of a sealed battery by interposing in the sealing area of the battery a sealing agent prepared by adding a magnetic fluid to asphalt. CONSTITUTION:100pts.wt. of blown asphalt is mixed with 20pts.wt. of Marbomagna FN-40, a ferromagnetic body used as a magnetic fluid, using a liquid paraffin as a solvent to prepare a sealing agent 4. Next, after the sealing agent 4 is applied to the inner circumference surface of the opening of an exterior can 2 also serving as a negative terminal, caulking is performed with an insulating packing 3 interposed between the exterior can 2 and a sealing body 1 also serving as a positive terminal to seal the battery, thereby constituting a sealed battery. As a result, the magnetic fluid existing in the sealing agent 4 is magnetized by a magnetic field produced in the battery during its charging and discharging to enhance the close contact between the sealing agent 4 and the exterior can 2, thereby enabling the liquid-leakage resistance of the battery to be improved by increasing the sealing effect.