Battery pack

1. A battery pack comprising:

at least one battery module comprising a plurality of unit cells stacked together;

at least one thermoelectric module on the at least one battery module, the at least one thermoelectric module comprising at least one thermoelectric device comprising a first heat transfer member contacting a first surface of the at least one thermoelectric device, and a second heat transfer member contacting a second surface of the at least one thermoelectric device generally opposite to the first surface; and

a plurality of heat pipes on the battery module and contacting the first heat transfer member and the battery module, wherein the heat pipes are accommodated in grooves on the first heat transfer member.

2. The battery pack of claim 1 , comprising:

a housing generally encompassing the at least one battery module,

wherein the second heat transfer member is a heat sink at least partially protruding from the housing.

3. The battery pack of claim 1 , wherein the at least one thermoelectric module comprises a Peltier device comprising an input terminal configured to receive a polarity-convertible current.

4. The battery pack of claim 3 , further comprising a battery management system comprising a switching device configured to convert a polarity of a current applied to an electrode of the Peltier device.

5. The battery pack of claim 3 , wherein the at least one thermoelectric module further comprises a temperature sensor, and wherein the at least one thermoelectric module is configured to convert a polarity of a current applied to an electrode of the Peltier device based on a temperature measured by the temperature sensor.

6. The battery pack of claim 5 , comprising a plurality of thermoelectric modules, wherein each of the thermoelectric modules is configured to operate independently.

7. The battery pack of claim 1 , wherein the at least one thermoelectric module is mounted on at least a first side of the battery module.

8. The battery pack of claim 7 , wherein the at least one thermoelectric module comprises at least two thermoelectric modules mounted on the battery module and extending in directions substantially perpendicular to each other.

9. The battery pack of claim 8 , wherein the at least two thermoelectric modules each comprise at least one thermoelectric device including a positive input terminal and a negative input terminal, a first heat transfer member contacting a first surface of the at least one thermoelectric device, and a second heat transfer member contacting a second surface of the at least one thermoelectric device.

10. The battery pack of claim 1 , wherein a first thermoelectric module of the at least one thermoelectric module is located on a first end of the unit cells and a second thermoelectric module of the at least one thermoelectric module is located on a second end of the unit cells to fix the unit cells together.

11. The battery pack of claim 1 , wherein the at least one thermoelectric device further comprises a positive input terminal and a negative input terminal.

12. The battery pack of claim 1 , wherein the battery pack is configured to power an electric bicycle.

13. The battery pack of claim 1 , wherein the at least one thermoelectric module is mounted on the at least one battery module and configured to selectively heat or cool the at least one battery module.

14. The battery pack of claim 1 , wherein the heat pipes extend along the battery module in a first direction and in a second direction substantially perpendicular to the first direction.