Method and apparatus for charging a secondary battery by supplying pulsed current as charging current

In a method for charging a secondary battery having a positive electrode, a negative electrode, and an electrolyte, a pulsed current is supplied to the secondary battery to make the pulsed current flow between the positive electrode and the negative electrode through the electrolyte to thereby charge the secondary battery. The pulsed current comprises positive pulse current which has a positive pulse amplitude corresponding to a first current density of 1 μA/cm2 to 100 mA/cm2 in the positive electrode. However, the pulsed current may include a negative pulse current following after each positive pulse and having a negative amplitude corresponding to a second current density not greater than a quarter of the first current density.