Battery pack
A battery pack includes a pack housing, and at least one battery assembly accommodated in the pack housing. The battery assembly includes a first cell stack and a second cell stack in each of which a plurality of battery cells are stacked, and a busbar assembly electrically connecting the plurality of battery cells to each other. The busbar assembly includes a first coupling portion coupled to the first cell stack, a second coupling portion coupled to the second cell stack, and a connection portion connecting the first coupling portion and the second coupling portion to each other.
1 . A battery pack comprising:
a pack housing including an inner space and a partition wall member partitioning the inner space into multiple accommodating spaces; and
at least one battery assembly accommodated in the pack housing,
wherein the partition wall member includes a venting portion,
wherein the battery assembly includes:
a first cell stack and a second cell stack in each of which a plurality of battery cells are stacked and are disposed in different accommodating spaces, respectively, and
a busbar assembly electrically connecting the plurality of battery cells to each other,
wherein the busbar assembly includes:
a first coupling portion coupled to the first cell stack,
a second coupling portion coupled to the second cell stack, and
a connection portion connecting the first coupling portion and the second coupling portion to each other,
wherein the connection portion includes a breakable portion formed of a material different from that of the first coupling portion and the second coupling portion, and
wherein the breakable portion is disposed to oppose the venting portion, and is melted by high-temperature and high-pressure gas discharged from the venting portion or by an overcurrent, thereby cutting off an electrical connection between the first cell stack and the second cell stack.
2 . The battery pack of claim 1 , wherein the busbar assembly includes:
multiple busbars disposed on the first coupling portion and the second coupling portion to be bonded to the plurality of battery cells; and
a support plate to which the multiple busbars are fixedly fastened.
3 . The battery pack of claim 2 , wherein the multiple busbars further includes a bridge busbar interconnecting a first busbar disposed on the first coupling portion and a second busbar disposed on the second coupling portion.
4 . The battery pack of claim 3 , wherein the bridge busbar is integrally formed with the first busbar and the second busbar.
5 . The battery pack of claim 3 , wherein at least a portion of the bridge busbar is embedded in the support plate.
6 . The battery pack of claim 3 , wherein the bridge busbar includes the breakable portion formed of a material different from that of the multiple busbars, and the breakable portion is fused at a temperature lower than a melting point of the multiple busbars.
7 . The battery pack of claim 6 , wherein at least a portion of the breakable portion is formed to have a cross-sectional area smaller than those of other portions of the bridge busbar.
8 . The battery pack of claim 6 , wherein
the multiple busbars are formed of a copper material, and
the breakable portion is formed of an aluminum material.
9 . The battery pack of claim 6 , wherein the breakable portion is entirely embedded in the support plate.
10 . The battery pack of claim 3 , wherein the bridge busbar has at least one through-hole formed therein.
11 . The battery pack of claim 1 , wherein the connection portion of the busbar assembly includes an insertion groove into which the partition wall member is inserted.
12 . The battery pack of claim 1 , wherein
an inner space of the partition wall member is used as a gas flow path through which gas moves, and
the venting portion discharges the gas toward the venting portion.
13 . A battery pack comprising:
a pack housing including a partition wall member partitioning an inner space into multiple accommodating spaces; and
at least one battery assembly accommodated in the accommodating spaces,
wherein the battery assembly includes:
a first cell stack and a second cell stack in which a plurality of battery cells are stacked and are disposed in different accommodating spaces, respectively, and
a busbar assembly to which the first cell stack and the second cell stack are fixedly coupled,
wherein the partition wall member includes a venting portion, and is disposed to cross between the first cell stack and the second cell stack, and
wherein the busbar assembly includes a bridge busbar including a breakable portion and an insertion groove into which the partition wall member is inserted,
wherein the breakable portion is disposed to oppose the venting portion, and is melted by high-temperature and high-pressure gas discharged from the venting portion, thereby cutting off electrical insulation between the first cell stack and the second cell stack.
14 . The battery pack of claim 13 , wherein the busbar assembly includes:
a first busbar coupled to the first cell stack, and
a second busbar coupled to the second cell stack,
wherein
the bridge busbar interconnects the first busbar and the second busbar, and
a support plate to which the first busbar, the second busbar, and the bridge busbar are fixedly fastened.
15 . The battery pack of claim 14 , wherein at least a portion of the bridge busbar is embedded in the support plate.
16 . The battery pack of claim 14 , wherein the breakable portion melts at a temperature lower than melting points of the first and second busbars.
17 . The battery pack of claim 13 , wherein
an inner space of the partition wall member is used as a gas flow path through which gas moves, and
wherein the venting portion is provided to discharge the gas outside of the partition wall member.