A battery pack comprising: a plurality of unit modules, wherein each unit module includes a case and a rechargeable battery cell inserted in the case, continuously disposed in a first direction; a unit cooling member having a through-passage and positioned below each unit module; and a pressure member pressing the unit cooling member, wherein the pressure member includes: a first pressure member connected to the through-passage having an inlet part and outlet part where the coolant inflows and is discharged; and a second pressure member coupled with the first pressure member to press the unit cooling member, and wherein the unit cooling member is arranged in the first direction and includes a first unit cooling member neighboring the first pressure member, a third unit cooling member neighboring the second pressure member, and at least one second unit cooling member disposed between the first unit cooling member and the third unit cooling member, and wherein each unit cooling member has a plurality of through-passages extending in the first direction, and the through-passages of neighboring unit cooling members are connected to each other, and wherein the first unit cooling member has a first through-passage having a pair of linear through-passages (21a1) respectively connected to the inlet part and the outlet part and a curved through-passage (21a2) disposed between the linear through-passages (21a1) and formed with both ends respectively opened toward the second unit cooling member side, the second unit cooling member has a plurality of second through-passages respectively connected to both ends and extending in the first direction, and the second through-passage is disposed to be connected to the first through-passage, and the third unit cooling member has a plurality of third curved through-passages having both ends opened in the second unit cooling member side and connecting neighboring second through-passages, and wherein through-passages of the unit cooling members neighboring in the first direction are connected so that a coolant flows. a plurality of unit modules, wherein each unit module includes a case and a rechargeable battery cell inserted in the case, continuously disposed in a first direction; a unit cooling member having a through-passage and positioned below each unit module; and a pressure member pressing the unit cooling member, wherein the pressure member includes: a first pressure member connected to the through-passage having an inlet part and outlet part where the coolant inflows and is discharged; and a second pressure member coupled with the first pressure member to press the unit cooling member, and wherein the unit cooling member is arranged in the first direction and includes a first unit cooling member neighboring the first pressure member, a third unit cooling member neighboring the second pressure member, and at least one second unit cooling member disposed between the first unit cooling member and the third unit cooling member, and wherein each unit cooling member has a plurality of through-passages extending in the first direction, and the through-passages of neighboring unit cooling members are connected to each other, and wherein the first unit cooling member has a first through-passage having a pair of linear through-passages (21a1) respectively connected to the inlet part and the outlet part and a curved through-passage (21a2) disposed between the linear through-passages (21a1) and formed with both ends respectively opened toward the second unit cooling member side, the second unit cooling member has a plurality of second through-passages respectively connected to both ends and extending in the first direction, and the second through-passage is disposed to be connected to the first through-passage, and the third unit cooling member has a plurality of third curved through-passages having both ends opened in the second unit cooling member side and connecting neighboring second through-passages, and wherein through-passages of the unit cooling members neighboring in the first direction are connected so that a coolant flows.