Onboard battery for vehicle

1. An onboard battery for a vehicle comprising:

at least one battery module including battery cells disposed in a predetermined state, and a cell cover in which the battery cells are disposed, at least one part of an internal space of the cell cover being formed as at least one chamber into which cooling air is sent;

a housing case that houses the battery module;

at least one intake duct through which the cooling air is sent into the at least one battery module;

at least one exhaust duct through which the cooling air sent into the at least one battery module is discharged;

a heater that is disposed in the at least one chamber, and heats the battery cells; and

a heat sink that is disposed in the at least one chamber, located opposite to the battery cells, and attached to the heater, wherein:

the heat sink includes a base body formed by a resin material, and a heat conductor provided to an outer surface of the base body and formed by a metal material,

the base body includes a flat base plate section attached to the heater, and at least one protrusion protruding to the battery cells from the base plate section, and

the heat conductor is provided to a portion of the at least one protrusion, other than an end surface of the protrusion.

2. The onboard battery for a vehicle according to claim 1 , wherein:

the at least one protrusion comprises multiple protrusions, and

each of the multiple protrusions is formed in a shape extending in a direction in which the battery cells are disposed.

3. The onboard battery for a vehicle according to claim 2 , wherein the heat sink has heat transferring holes opened to the heater side and the battery cell side, respectively.

4. The onboard battery for a vehicle according to claim 2 , further comprising:

at least one cooling fan that causes the cooling air to flow is provided,

wherein driving of the at least one cooling fan is stopped when the heater is driven.

5. The onboard battery for a vehicle according to claim 2 , further comprising a heat insulating material that is attached to an outside of the at least one chamber in an outer surface of the at least one battery module.

6. The onboard battery for a vehicle according to claim 2 , wherein:

the at least one battery module comprises two battery modules,

the two battery modules are disposed to be adjacent to each other,

the at least one chamber of one of the adjacent battery modules and the at least one chamber of the other battery module communicate with each other,

the heater is disposed at a boundary of the at least one chamber of the one of the battery modules and the at least one chamber of the other battery module, and

the heat sink is disposed on each of two sides of the heater.

7. The onboard battery for a vehicle according to claim 1 , wherein the heat sink has heat transferring holes opened to the heater side and the battery cell side, respectively.

8. The onboard battery for a vehicle according to claim 1 , further comprising:

at least one cooling fan that causes the cooling air to flow,

wherein driving of the at least one cooling fan is stopped when the heater is driven.

9. The onboard battery for a vehicle according to claim 1 , further comprising a heat insulating material that is attached to an outside of the at least one chamber in an outer surface of the at least one battery module.

10. The onboard battery for a vehicle according to claim 1 , wherein the at least one battery module comprises two battery modules,

the two battery modules are disposed to be adjacent to each other,

the at least one chamber of one of the adjacent battery modules and the at least one chamber of the other battery module communicate with each other,

the heater is disposed at a boundary of the at least one chamber of the one of the battery modules and the at least one chamber of the other battery module, and

the heat sink is disposed on each of two sides of the heater.