NOVELTY - The structure has a first connecting duct connecting a first duct to a third duct and extending in a vehicle width direction. A second connecting duct connects a second duct to a fourth duct and extending in the vehicle width direction, where the second connecting duct allows heat exchange with a battery group (B2). A third connecting duct connects a third duct to a fifth duct, and extends in the vehicle width direction, where the third connecting duct allows heat exchange with another battery group (B3). A bypass duct connects the fifth duct to the second duct or to the first duct.    USE - Battery cooling structure for use in an electric vehicle.    ADVANTAGE - The structure collects water on upper surfaces of a heat exchange panel, which flows through drainage holes of longitudinal frame members and into interiors of hollow frames passing through drainage pipes passing vertically through the third and fourth ducts, and discharged to a lower surface of a tray, thus preventing degradation of battery modules in an effective manner. The structure blocks an entry of water from the drainage pipes into the tray in an effective manner. The structure utilizes the longitudinal frame members to discharge water so as to prevent an increase in a number of components and reduce complexity of the structure in an effective manner. The fifth duct communicates through the bypass duct with the second duct so as to reduce time during which high-temperature air after heat exchange stays inside the fifth duct, and prevent easy occurrence of heat exchange with low-temperature air inside the fourth duct, thus minimizing temperature rise of air inside the fourth duct and minimizing the degradation of an effect of cooling the battery group in an effective manner.    DESCRIPTION OF DRAWING(S) - The drawing shows a perspective view of a battery unit of an electric vehicle.    Battery groups (B1-B6)    Tray (11)    Battery modules (12)    Mounting bracket (14)    Cross member (15)    Fan unit (19)