Battery cell assembly comprising heat exchanger with spiral flow path

Provided is a battery cell assembly comprising both a battery cell and a heat exchanger which is mounted adjacent to the battery cell to cool the battery cell. The heat exchanger has an outer housing. The outer housing comprises an interior region and first and second flow guide members. The first and second flow guide members comprise a spiral flow path inside the interior region and are totallytilted in the interior region upwardly. The spiral flow path extends from an inlet aperture inside the outer housing to another flow path of the outer housing, wherein another flow path extends from the spiral flow path to an outlet aperture. Another flow path has a smaller cross-sectional area than those of each portion of the spiral flow path so that bubbles in the fluid flowing into the inlet aperture are pressurized while moving upward through the spiral flow path and the discharge of the bubbles through the outer housing from the outlet aperture is accelerated through another flow path.