NOVELTY - A battery module (100) comprises a cell barrier (20) interposed between two unit cells (10) and having a plate (23) that comprises a first surface facing the first unit cell, a second surface facing the second unit cell, two protrusions (21) protruding from two surfaces. Parts of protrusions contact the first and second unit cells, respectively, such that the plate is separated from the unit cell with a gap in-between and a fluid passage is formed between the plate and the unit cell through the gap.    USE - Used as a power source for driving a motor of a hybrid electric automobile.    ADVANTAGE - The cell barrier may improve the efficiency of cooling unit cells as it increases the diffusion rate of a coolant within the space formed by the cell barrier by letting the coolant to hit the protrusions often while passing. The cell barrier may have effects on appropriately supporting the unit cell without being inclined to one side, and is designed to flow the coolant in a direction parallel to the longer edge of the plate. This configuration allows the coolant to stay longer within the space formed by the cell barriers.    DETAILED DESCRIPTION - A battery module comprises unit cells comprising a first unit cell and a second unit cell; and a cell barrier interposed between the two unit cells. The cell barrier comprises a plate that comprises a first surface facing the first unit cell; a second surface facing the second unit cell; protrusions protruding from the first surface, where part of the protrusions contact the first unit cell such that the plate is separated from the first unit cell with a gap in-between and a fluid passage is formed between the plate and the first unit cell through the gap; and at least one protrusion protruding from the second surface, where the protrusion contacts the second unit cell such that the plate is separated from the second unit cell with a gap in-between and a fluid passage is formed between the plate and the second unit cell through the gap. INDEPENDENT CLAIMS are also included for:    (1) a method of cooling a battery module; and    (2) a method of making a battery module.    DESCRIPTION OF DRAWING(S) - The figure is a schematic perspective view of a battery.    Unit cells (10)    Cell barrier (20)    Protrusions (21)    Plate (23)    Battery module (100)