Battery assemblies, vehicles, and methods with gas manifold liners and battery tray seals for improved cell gas venting
Presented are battery assemblies with gas manifold liners and support tray seals for optimized gas venting, methods for making/using such battery assemblies, and vehicles equipped with such battery assemblies. A battery assembly, such as a rechargeable high-voltage traction battery pack, includes a support tray that seats thereon a cold plate. The cold plate is formed with a thermally conductive material and includes a gas manifold that exhausts gases from the battery assembly. At least one battery cell is supported on the cold plate and includes a cell case that contains a galvanic electrochemical cell and has a cell vent fluidly coupled with the gas manifold. A manifold liner is located within and abuts opposing walls of the gas manifold. The manifold insert includes one or more thermal barrier layers, each formed with a thermally insulating material, and one or more electrical barrier layers, each formed with an electrically insulating material.
1 . A battery assembly comprising:
a cold plate formed with a thermally conductive material and defining therethrough a gas manifold configured to exhaust gases from the battery assembly;
a battery cell including a cell case adjacent the cold plate, the cell case containing an electrochemical cell and having a cell vent in fluid communication with the gas manifold; and
a manifold liner located within and abutting opposing walls of the gas manifold, the manifold liner including a thermal barrier layer formed with a thermally insulating material and an electrical barrier layer attached to the thermal barrier layer and formed with an electrically insulating material, the electrical barrier layer including a first electrical barrier layer abutting a first inner surface of the gas manifold and a second electrical barrier layer abutting a second inner surface of the gas manifold, wherein the first and second electrical barrier layers each has a C-shaped transverse cross section and is friction fit onto a respective flange of the cold plate.
2 . The battery assembly of claim 1 , wherein the thermal barrier layer includes first and second thermal barrier layers extending across and substantially coterminous with opposing first and second sides, respectively, of the gas manifold.
3 . The battery assembly of claim 2 , wherein the first and second thermal barrier layers include first and second flexible mica sheets, respectively.
4 . The battery assembly of claim 3 , wherein the first thermal barrier layer includes a frangible segment configured to rupture at a predetermined surface pressure produced by cell gases released by the battery cell through the cell vent.
5 . The battery assembly of claim 4 , wherein the frangible segment of the first flexible mica sheet includes perforations, a tear seam, and/or a reduced-thickness area.
6 . The battery assembly of claim 2 , wherein the first thermal barrier layer has a first transverse width and the second thermal barrier layer has a second transverse width distinct from the first transverse width.
7 . The battery assembly of claim 1 , wherein the first and second electrical barrier layers extend across and are substantially coterminous with the first and second inner surfaces, respectively, of the gas manifold.
8 . The battery assembly of claim 7 , wherein the first and second electrical barrier layers include first and second fiber reinforced polymer (FRP) rails, respectively.
9 . The battery assembly of claim 1 , further comprising a first fluid seal strip formed with a thermally expanding material and located between the manifold liner and the cold plate.
10 . The battery assembly of claim 9 , further comprising:
a battery support tray seating thereon the cold plate; and
a second fluid seal strip formed with the thermally expanding material and located between the cold plate and the battery support tray.
11 . The battery assembly of claim 10 , further comprising a third fluid seal strip formed with the thermally expanding material and adjoining a side surface of the cold plate and a top surface of the battery support tray.
12 . The battery assembly of claim 11 , wherein the thermally expanding material of the first, second, and third fluid seal strips includes a conformable self-adhering intumescent putty.
13 . A motor vehicle, comprising:
a vehicle body with a passenger compartment;
a plurality of road wheels attached to the vehicle body;
a traction motor attached to the vehicle body and operable to drive one or more of the road wheels to thereby propel the motor vehicle; and
a traction battery pack electrically connected to and operable to power the traction motor, the traction battery pack including:
a battery support tray attached to the vehicle body;
a cold plate seated on the battery support tray, formed with a thermally conductive material, and defining therethrough a gas manifold configured to exhaust gases from the traction battery pack;
a plurality of battery cells each including a cell case seated on the cold plate, each of the cell cases containing an electrochemical cell and having a cell vent in fluid communication with the gas manifold;
a manifold liner sleeve located within and abutting opposing inner surfaces of the gas manifold, the manifold liner sleeve including opposing first and second thermal barrier layers, each formed with a thermally insulating material, and opposing first and second electrical barrier layers, each attached to the thermal barrier layers and formed with an electrically insulating material, the first and second electrical barrier layers abutting opposing first and second inner surfaces, respectively, of the gas manifold, wherein the first and second electrical barrier layers each has a C-shaped transverse cross section and is friction fit onto a respective flange of the cold plate; and
a fluid seal strip formed with a conformable and self-adhering thermally expanding material, the fluid seal strip being located between the cold plate and the manifold liner and/or the battery support tray.
14 . A method of constructing a battery assembly, the method comprising:
receiving a cold plate formed with a thermally conductive material and defining therethrough a gas manifold configured to exhaust gases from the battery assembly;
locating a battery cell with a cell case adjacent the cold plate, the cell case containing an electrochemical cell and having a cell vent, the battery cell being located such that the cell vent is in fluid communication with the gas manifold; and
locating a manifold liner within and abutting opposing inner surfaces of the gas manifold, the manifold liner including a thermal barrier layer formed with a thermally insulating material and an electrical barrier layer attached to the thermal barrier layer and formed with an electrically insulating material, the electrical barrier layer including a first electrical barrier layer abutting a first inner surface of the gas manifold and a second electrical barrier layer abutting a second inner surface of the gas manifold, wherein the first and second electrical barrier layers each has a C-shaped transverse cross section and is friction fit onto a respective flange of the cold plate.
15 . The method of claim 14 , wherein the thermal barrier layer includes first and second thermal barrier layers extending across and substantially coterminous with opposing first and second sides, respectively, of the gas manifold.
16 . The method of claim 15 , wherein the first and second thermal barrier layers include first and second flexible mica sheets, respectively.
17 . The method of claim 14 , wherein the first and second electrical barrier layers extend across and are substantially coterminous with the first and second inner surfaces, respectively, of the gas manifold.
18 . The method of claim 17 , wherein the first and second electrical barrier layers include first and second fiber reinforced polymer (FRP) rails, respectively.
19 . The method of claim 14 , further comprising:
locating the cold plate on a battery support tray;
locating a first fluid seal strip between the manifold liner and the cold plate, the first fluid seal strip being formed with a thermally expanding material; and
locating a second fluid seal strip between the cold plate and the battery support tray, the second fluid seal strip being formed with the thermally expanding material.
20 . The method of claim 19 , further comprising locating a third fluid seal strip against a side surface of the cold plate and a top surface of the battery support tray, the third fluid seal strip being formed with the thermally expanding material.