Abstract: An apparatus and method for fusing the ends of battery cell terminal posts and the ends of hollow bushings fixed in the plastic cover of a battery being assembled and within which the terminal posts are concentrically disposed. The apparatus includes a pair of induction heating coils which each concentrically support a mold cavity insert adapted to receive the ends of the terminal posts and bushings to be fused and a ferrite insert adapted to concentrate induced current in the ends of the terminal post and bushings upon energization of the coils. An electrical control is provided for selectively generating a radio-frequency oscillating current in the coils to effect heating, melting, and fusion of the ends of the terminal posts and bushings to consistent fusion depths while the plastic battery case remains substantially uneffected.