JP2013098105A - Battery module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery module which inhibits holes from opening in a smoke exhaustion cover more effectively compared to a conventional battery module.SOLUTION: A battery module has a rib 70 which is provided protruding from a smoke exhaustion cover 60 into a smoke exhaustion gas passage R, and onto which a gas discharged from a safety valve 33 directly blows. Thus, heat (heat energy) of the gas discharged from the safety valve 33 is entirely or partially absorbed by the rib 70. Thus, compared to a (conventional) case where the rib 70 is not provided, the battery module inhibits the gas discharged from the safety valve 33 from melting the smoke exhaustion cover 60 and forming holes in the smoke exhaustion cover 60 more effectively.

Description

  The present invention relates to a battery module having a smoke exhaust cover that forms a smoke exhaust gas passage for discharging gas released from a safety valve of a battery to the outside of a vehicle.

Japanese Patent Application Laid-Open No. 2008-262733 covers at least a part of a smoke exhaust cover (exhaust cover) that covers the safety valve of the battery and extends in the stacking direction of the battery from the outside (above) of the smoke exhaust cover with a flame retardant member. The technology is disclosed.
According to the technology disclosed in the above publication, when the smoke exhaust cover is melted by the fluid discharged from the battery safety valve and the smoke exhaust cover has a hole, the fluid around the battery module is discharged from the battery safety valve. Can be suppressed from being affected.

However, the technique disclosed in the above publication has the following problems.
It is not possible to prevent the smoke exhaust cover from being perforated by the fluid discharged from the battery safety valve. Therefore, there is room for improvement in terms of suppressing the fluid discharged from the safety valve from flowing out of the smoke exhaust cover through the hole opened in the smoke exhaust cover.

JP 2008-262733 A

  The objective of this invention is providing the battery module which can suppress that a smoke exhaust cover has a hole compared with the past.

The present invention for achieving the above object is as follows.
(1) (a) Lamination formed by alternately laminating a battery including a safety valve that discharges gas to the outside of the battery when the battery temperature rises and the battery internal pressure becomes a predetermined value or more, and a resin frame Body,
(B) a smoke exhaust cover that covers the safety valve and extends in the stacking direction of the laminate, and forms a smoke exhaust gas flow path through which the gas released from the safety valve flows. ,
(C) a rib protruding from the smoke exhaust cover into the smoke exhaust gas flow path and provided at a position corresponding to at least the safety valve;
A battery module.
(2) The battery module according to (1), wherein the rib is provided to extend in a direction in which the smoke exhaust cover extends.
(3) The battery module according to (2), wherein only one rib is provided to extend in a direction in which the smoke exhaust cover extends.

According to the battery module of (1) above, since the rib is provided in the position corresponding to the safety valve, protruding from the smoke exhaust cover into the smoke exhaust gas flow path, the following effects can be obtained.
The gas released from the safety valve directly hits the rib. Therefore, all or part of the heat (thermal energy) of the gas released from the safety valve can be absorbed by the rib. Therefore, compared with the case where the rib is not provided (conventional), it is possible to suppress the smoke exhaust cover from being melted by the gas released from the safety valve and opening the smoke exhaust cover.

According to the battery module of (2) above, the ribs are provided so as to extend in the direction in which the smoke exhaust cover extends, so the following effects can be obtained.
The rigidity of the smoke exhaust cover can be improved. Therefore, deformation of the smoke exhaust cover can be suppressed as compared with the case where the rib is provided extending in a direction other than the direction in which the smoke exhaust cover extends.

According to the battery module of (3), since only one rib is provided, the following effects can be obtained.
Compared with the case where a plurality of ribs are provided, the pressure loss of the gas flow flowing through the flue gas passage can be reduced. Moreover, it is advantageous in terms of material cost compared to the case where a plurality of ribs are provided.

It is a model side view only of a laminated body of the battery module of this invention Example. It is a schematic perspective view of the battery of the battery module of an Example of this invention. It is a perspective view of a smoke exhaust cover and a sealing member of a battery module of an embodiment of the present invention. It is a model expanded sectional view which shows the positional relationship of a battery, a smoke exhaust cover, a rib, and a sealing member of the battery module of this invention Example.

Below, the battery module of this invention Example is demonstrated with reference to FIGS.
The battery module 10 according to the embodiment of the present invention is mounted on, for example, an electric vehicle. As shown in FIG. 4, the battery module 10 includes a stacked body 20, a smoke exhaust cover 60, a rib 70, and a seal member 80. However, the seal member 80 is not an essential component.

As shown in FIG. 1, the laminated body 20 is formed by alternately laminating batteries 30 and resin frames (resin plates) 40 that are heating elements.
In addition to the resin frame 30 and the battery 40, the stacked body 20 further includes end plates 50 and 50 provided at both ends in the stacking direction of the stacked body 20. The end plates 50 and 50 at both ends in the stacking direction of the stacked body 20 are connected to each other using unillustrated restraining bands extending in the stacking direction of the stacked body 20. The laminated body 20 is restrained by a restraining band (not shown).

  The battery 30 is a square battery as shown in FIG. The battery 30 has a substantially rectangular plate shape when viewed from the front (when viewed from the stacking direction of the stacked body 20) except for the positive electrode terminal 31 and the negative electrode terminal 32 provided on the upper portion (upper surface). The battery 30 is a secondary battery such as a lithium ion battery or a nickel metal hydride battery. Each battery 30 is electrically connected in series.

In the upper part (upper surface) of the battery 30, when the temperature of the battery 30 rises due to an internal short circuit of the battery 30 and the internal pressure of the battery 30 exceeds a predetermined value, the gas in the battery 30 is transferred to the outside of the battery 30. A discharge safety valve 33 is provided. Hereinafter, the surface of the battery 30 on which the safety valve 33 is provided is referred to as a safety valve arrangement surface 30a.
The safety valve 33 is provided at the center (including the vicinity) of the positive terminal 31 and the negative terminal 32. The safety valve 33 is formed, for example, by covering a hole (not shown) that communicates the inside and the outside of the battery 30 with a film (not shown). When the temperature of the battery 30 rises and the internal pressure of the battery 30 exceeds a predetermined value, the membrane (not shown) is broken, and the gas in the battery 30 is released from the battery 30 through the hole (not shown). The gas from the safety valve 33 is released in the direction perpendicular to the surface of the safety valve arrangement surface 30a (upward).

  As shown in FIG. 1, the resin frame 40 is disposed between adjacent batteries 30 in the stacking direction of the stacked body 20. The resin frame 40 is made of resin and made of an insulating material (for example, made of polypropylene). The resin frame 40 is an injection-molded product and has a single component configuration. However, the resin frame 40 may have a multi-part configuration. The resin frame 40 has a substantially rectangular plate shape when viewed from the front (when viewed from the stacking direction of the stacked body 20). One side of the front and back sides of the resin frame 40 is an uneven surface, and a coolant channel is formed between the battery 30 and the battery 30 that is in a position facing the one side and in contact therewith. The front and back other side surfaces of the resin frame 40 are flat to reduce the distance in the stacking direction of the stacked body 20 and to make the stacked body 20 compact. doing. However, the front and back other side surfaces of the resin frame 40 may be uneven as well as the front and back side surfaces of the resin frame 40.

The smoke exhaust cover 60 is not made of metal but made of an insulating material to enable electrical insulation and reduce costs. The smoke exhaust cover 60 is a molded product. Although the smoke exhaust cover 60 may have a multi-part configuration, as shown in FIG. 3, it is desirable that the smoke exhaust cover 60 has a single-part configuration to reduce the number of components. The smoke exhaust cover 60 is made of a material that softens (melts) when heated, and is made of, for example, a thermoplastic resin. The smoke exhaust cover 60 is made of a material that softens (melts) at a temperature lower than the temperature of the gas released from the safety valve 33 to the outside of the battery 30.

The smoke exhaust cover 60 extends in the stacking direction of the stacked body 20 and covers the safety valve 33 from above. The smoke exhaust cover 60 is fixed at one end in the extending direction (including the vicinity thereof) to the end plate 50 at one end in the stacking direction of the stacked body 20 using clips, rivets, screws, screws, bolts, etc. (not shown). At the other end in the extending direction (including the vicinity thereof), a clip, a rivet, a screw, a screw, a bolt, etc. (not shown) is used for the end plate 50 at the other end in the stacking direction of the stacked body 20. It is fixedly installed. A tube 63 whose internal channel communicates with the outside of the vehicle is connected to one end of the smoke exhaust cover 60 in the extending direction.

As shown in FIG. 4, the cross-sectional shape of the portion excluding both ends in the extending direction of the smoke exhaust cover 60 is, for example, a U shape (substantially U shape, U shape, substantially U shape) that opens to the laminated body 20 side. Shape). The smoke exhaust cover 60 includes a pair of side walls 61 and 61 extending in a direction away from the stacked body 20 and a direction in which the pair of side walls 61 and 61 extend in a cross-sectional view of a portion excluding both ends of the smoke exhaust cover 60 in the extending direction. And a ceiling wall 62 that connects the tip portions.

The pair of side walls 61 and 61 are flange portions that increase the contact area with the laminate 20 and increase the sealing performance of the gap between the laminate 20 and the smoke exhaust cover 60 at the end on the laminate 20 side, respectively. 61a. The pair of side walls 61, 61 may extend linearly in a direction away from the laminate 20 in a cross sectional view of the smoke exhaust cover 60, and extend with at least one curved portion or bent portion. It may be.

A part of the ceiling wall 62 is at a position facing the safety valve 33 in the direction perpendicular to the safety valve arrangement surface 30a. A part of the ceiling wall 62 is directly above the safety valve 33. The ceiling wall 62 may extend linearly from one of the pair of side walls 61, 61 to the other in a cross-sectional view of the smoke exhaust cover 60, and extends with at least one curved portion or bent portion. It may be.

As shown in FIG. 4, the smoke exhaust cover 60 forms a smoke exhaust gas flow path R through which the gas released from the safety valve 33 flows. The smoke exhaust gas flow path R extends in the stacking direction of the stacked body 20, which is the direction in which the smoke exhaust cover 60 extends. As shown in FIG. 3, only one end in the extending direction of the flue gas passage R is an open end R1, and the other end in the extending direction of the flue gas passage R is a closed end R2. The open end R1 of the flue gas passage R is located at one end of the flue gas cover 60 in the extending direction, and the closed end R2 of the flue gas passage R is at the other end of the flue gas cover 60 in the extending direction. positioned. The flue gas passage R communicates with the passage in the tube 63.
The gas released from the safety valve 33 to the outside of the battery 30 flows into the flue gas flow path R, flows through the flue gas flow path R, flows into the flow path in the tube 63 from the open end R1, and flows in the tube 63. It flows through the road and is discharged outside the vehicle.

  The rib 70 is provided in the smoke exhaust cover 60 as shown in FIG. The rib 70 may be formed separately from the smoke exhaust cover 60 and fixedly attached to the smoke exhaust cover 60. However, the number of parts is reduced, and deformation (warpage) due to sink marks when the smoke exhaust cover 60 is molded is suppressed. In view of suppressing deformation of the smoke exhaust cover 60 including, it is desirable that the smoke exhaust cover 60 be formed integrally (molded integrally). The rib 70 is made of a material that softens (melts) when heated, and is made of, for example, a thermoplastic resin. The rib 70 is made of a material that softens (melts) at a temperature lower than the temperature of the gas released from the safety valve 33 to the outside of the battery 30.

The rib 70 is a surface facing the safety valve 33 of the ceiling wall 62 of the smoke exhaust cover 60 (a surface on the side of the smoke exhaust gas flow path R, a surface in contact with the smoke exhaust gas flow path R, hereinafter referred to as a safety valve facing surface) 62a. Is provided. The rib 70 is provided at a position corresponding to at least the safety valve 33. The position corresponding to the safety valve is a position where the gas released from the safety valve 33 directly hits. The rib 70 is provided so as to protrude from the safety valve facing surface 62a into the flue gas flow path R in a direction approaching the safety valve 33 (downward and in a direction opposite to the direction in which the gas released from the safety valve 33 is released). The gas released from the nozzle directly hits the front end (lower end) in the protruding direction.
The width of the rib 70 becomes smaller as it goes to the front end in the protruding direction (downward). The protruding end (lower end) of the rib 70 is not in contact with the battery 30 in order to prevent the rib 70 from destroying the safety valve 33.

  The ribs 70 are provided so as to extend continuously in the direction in which the smoke exhaust cover 60 extends except for both ends in the direction in which the smoke exhaust cover 60 extends. A plurality of ribs 70 may be provided, but it is desirable that only one rib 70 is provided in order to reduce the pressure loss of the gas flow flowing through the flue gas passage R.

  The seal member 80 is disposed between the laminated body 20 and the smoke exhaust cover 60 so as to be in surface contact with both sides in a compressed state, and seals the gap between the laminate 20 and the smoke exhaust cover 60. Yes. The seal member 80 is formed separately from the stacked body 20 and the smoke exhaust cover 60. The seal member 80 may have a multi-part configuration, but it is desirable that the seal member 80 has a single-part configuration in order to reduce the number of parts. The surface of the seal member 80 that contacts the stacked body 20 is in contact with not only the resin frame 40 but also the battery 30.

The seal member 80 is not made of metal but is made of a non-metallic material and is made of an insulating material in order to enable electrical insulation and reduce costs. The seal member 80 is made of a material that is elastically deformable and softens (melts) when heated. For example, the seal member 80 is made of a thermoplastic resin (including a sponge) or rubber. The seal member 80 is a material that softens (melts) at a temperature lower than the temperature of the gas released from the safety valve 33 to the outside of the battery 30, and softens at a temperature lower than the surface temperature of the battery 30 when the safety valve 33 opens. It is a material that melts (melts), and further, a material that softens (melts) at a temperature lower than the melting point of the smoke exhaust cover 60.

  As shown in FIG. 3, the sealing member 80 has a plate shape (substantially including a plate shape) whose longitudinal direction is the stacking direction of the stacked body 20. In order to prevent the sealing member 80 from covering the safety valve 33 with the sealing member 80 and inhibiting the flow of the gas released from the safety valve 33 to the flue gas passage R, the sealing member 80 is arranged in the thickness direction. A penetrating through hole 81 is provided. The number of the through holes 81 may be the same as the number of the safety valves 33 so that one through hole 81 can correspond to one safety valve 33, and one layer of the stacked body 20 can correspond to a plurality of safety valves 33 with one through hole 81. A small number of safety valves 33 may be provided by forming a long hole extending in the stacking direction. In the illustrated example, the same number of the through holes 81 as the safety valves 33 is provided so that one through hole 81 can correspond to one safety valve 33.

Next, the operation of the embodiment of the present invention will be described.
(A) Since the rib 70 that protrudes from the smoke exhaust cover 60 into the smoke exhaust gas flow path R and is provided at a position corresponding to at least the safety valve 33, the following action can be obtained.
(A1) The gas released from the safety valve 33 can be first applied to the rib 70 instead of the smoke exhaust cover 60. Therefore, all or part of the heat (thermal energy) of the gas released from the safety valve 33 can be absorbed by the rib 70 (by softening (melting) the rib 70). Therefore, compared with the case where the rib 70 is not provided (conventional), it is possible to prevent the smoke exhaust cover 60 from being melted by the gas released from the safety valve 33 and the smoke exhaust cover 60 to be opened.
(A2) All or part of the heat of the gas released from the safety valve 33 can be absorbed by the rib 70. As a result, the smoke exhaust cover 60 is melted by the gas released from the safety valve 33 and a hole is opened in the smoke exhaust cover 60. Therefore, the thickness of the smoke exhaust cover 60 can be reduced as compared with the conventional case. Therefore, the battery module 10 is advantageous in terms of cost, mass, and space.

(B) Since the rib 70 is provided so as to extend in the extending direction of the smoke exhaust cover 60, the following action can be obtained.
The rigidity of the smoke exhaust cover 60 can be improved. Therefore, as compared with the case where the rib 70 is provided extending in a direction other than the direction in which the smoke exhaust cover 60 extends, deformation of the smoke exhaust cover 60 including deformation (warping) due to sink marks at the time of molding of the smoke exhaust cover 60 is effective. Can be suppressed.

(C) Since only one rib 70 is provided, the following operation can be obtained.
Compared with the case where a plurality of ribs 70 are provided, the pressure loss of the gas flow flowing through the flue gas passage R can be reduced. Moreover, it is more advantageous in terms of material cost and mold forming cost than in the case where a plurality of ribs 70 are provided.

(D) Since the rib 70 is provided integrally with the smoke exhaust cover 60, the number of parts is larger than when the smoke exhaust cover 60 is prevented from having a hole using a separate member from the smoke exhaust cover 60. This is advantageous in terms of cost.

(E) Since the rib 70 is provided in the flue gas flow path R, the space of the battery module 10 is advantageous as compared with the case where the rib 70 is provided outside the flue gas flow path R.

(F) At the rib 70, the gas released from the safety valve 33 can be divided into one side and the other side of the rib 70 (can be divided into two). Therefore, the heat and pressure of the gas released from the safety valve 33 can be dispersed, and the heat and pressure of the gas released from the safety valve 33 can be prevented from concentrating on one station.

DESCRIPTION OF SYMBOLS 10 Attachment structure of smoke exhaust cover to laminated body 20 Laminated body 30 Battery 30a Safety valve arrangement surface 31 Positive electrode terminal 32 Negative electrode terminal 33 Safety valve 40 Resin frame 50 End plate 52 Restraint band 60 Smoke exhaust cover 61 Side wall 62 Ceiling wall 62a Safety valve facing surface 63 Tube 70 Rib 80 Seal member 81 Through-hole R Exhaust gas channel R1 Open end R2 of exhaust gas channel Closed end of exhaust gas channel

Claims (3)

(A) a laminated body constituted by alternately laminating a battery including a safety valve that discharges gas to the outside of the battery when the battery temperature rises and the battery internal pressure becomes a predetermined value or more, and a resin frame;
(B) a smoke exhaust cover that covers the safety valve and extends in the stacking direction of the laminate, and forms a smoke exhaust gas flow path through which the gas released from the safety valve flows. ,
(C) a rib protruding from the smoke exhaust cover into the smoke exhaust gas flow path and provided at a position corresponding to at least the safety valve;
A battery module.   The battery module according to claim 1, wherein the rib is provided so as to extend in a direction in which the smoke exhaust cover extends.   The battery module according to claim 2, wherein only one rib is provided to extend in a direction in which the smoke exhaust cover extends.

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