JP6988307B2 - Battery pack system - Google Patents

Description

The present invention relates to a battery pack system.

Conventionally, a battery pack system including a battery pack in which a battery is housed inside a battery case is known (see, for example, Patent Document 1).

Patent Document 1 describes a power supply device for accommodating a plurality of batteries provided with a safety valve in a case. This power supply device has a battery compartment for accommodating a plurality of batteries and a partition wall for partitioning the inside of the case into an exhaust chamber for exhausting gas discharged from an opening of a safety valve of the batteries housed in the battery chamber. Be prepared. This partition wall is configured to allow gas to flow into the exhaust chamber without flowing into the battery compartment and to be discharged from the exhaust chamber to the outside of the case.

Japanese Unexamined Patent Publication No. 2012-15121

In the battery pack system as described above, an abnormality occurs in the battery to generate gas, and the gas discharged from the inside of the battery case to the outside reacts with oxygen outside the battery case (oxidation reaction) to generate high temperature gas. This may adversely affect the devices around the battery case. Therefore, by supplying an oxidation inhibitor for suppressing the oxidation reaction to the gas discharged from the inside of the battery case to the outside and mixing the gas with the oxidation inhibitor, the gas outside the battery case can be used. It is conceivable to suppress the oxidation reaction.

However, even if the oxidation inhibitor is simply supplied to the gas discharged from the inside of the battery case to the outside, the gas and the oxidation inhibitor are not sufficiently mixed, and the oxidation reaction of the gas outside the battery case is sufficiently suppressed. You may not be able to.

Therefore, in the present invention, when the oxidation inhibitor is supplied to the gas discharged from the inside of the battery case to the outside, the gas and the oxidation inhibitor are sufficiently mixed to carry out the oxidation reaction of the gas outside the battery case. The purpose is to suppress it sufficiently.

The battery pack system according to the present invention includes a battery pack containing a battery inside the battery case. The battery pack system has a gas discharge member having a gas discharge space inside that extends along a predetermined direction and communicates with the inside of the battery case, and gas discharged from the inside of the battery case into the gas discharge space. It is equipped with a gas swivel granting mechanism that swivels in the discharge space. The battery pack system further includes a supply mechanism for supplying the oxidation inhibitor to the gas in the gas discharge space, and the supply direction of the oxidation inhibitor by the supply mechanism is an angle with respect to the turning direction of the gas.

According to the battery pack system according to the present invention, when the oxidation inhibitor is supplied to the gas discharged from the inside of the battery case to the outside, the gas and the oxidation inhibitor are sufficiently mixed to be used outside the battery case. The oxidation reaction of the gas can be sufficiently suppressed.

It is a schematic diagram of a vehicle equipped with a battery pack system. It is a perspective view of the battery pack system which concerns on embodiment of this invention. It is an exploded perspective view of the battery pack system which concerns on embodiment of this invention. It is a schematic plan view of the battery pack system which concerns on embodiment of this invention. FIG. 4 is a cross-sectional view taken along the line AA of FIG. It is sectional drawing of a gas discharge member. It is sectional drawing of the gas discharge member which concerns on the modification. It is sectional drawing of the gas discharge member which concerns on the modification. It is a top view of the battery pack system which concerns on other embodiment of this invention. FIG. 7 is a cross-sectional view taken along the line BB of FIG. FIG. 8 is a cross-sectional view taken along the line CC of FIG. It is a top view of the battery pack system which concerns on other embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail together with drawings.

As shown in FIG. 1, the battery pack system 10A is installed in the electric vehicle 1 and supplies energy for running to the electric vehicle 1. Specifically, the battery pack system 10A is arranged under the floor (floor panel) 2 of the electric vehicle 1. The electric vehicle 1 includes not only a vehicle equipped with only an electric power train but also a hybrid vehicle equipped with both an internal combustion engine and an electric power train. In FIG. 1, reference numeral 3 indicates a driver's seat of the electric vehicle 1, and reference numeral 4 indicates a tire of the electric vehicle 1.

As shown in FIGS. 2 to 5, the battery pack system 10A according to the present embodiment includes a battery pack 11, a gas discharge mechanism 12, a gas discharge member 13, a gas swirl imparting mechanism 14, and a supply mechanism (oxidation suppression). Agent supply mechanism) 15 and the like. In FIGS. 2 and 3, the arrow FR indicates the front side of the vehicle, the arrow UP indicates the upper side of the vehicle, the arrow R indicates the right side in the vehicle width direction, and the arrow L indicates the left side in the vehicle width direction.

The battery pack 11 has a battery 16, a battery case 17 for accommodating the battery 16 inside, and a gas discharge port 18 formed in the battery case 17.

The battery case 17 is composed of a lower case 19 and an upper case 20. By combining and joining both the lower case 19 and the upper case 20, a closed space (battery storage space 21) is formed inside the battery case 17, and a plurality of batteries 16 are arranged in this closed space.

The lower case 19 is fixed to a vehicle body skeleton member (not shown). The lower case 19 is formed in a bottomed box shape in which the upper part of the box shape is open. Specifically, the lower case 19 has a bottom surface portion 19a and a side surface portion 19b extending upward from the outer peripheral edge of the bottom surface portion 19a.

The upper case 20 is joined to the lower case 19 at a plurality of points. The upper case 20 is formed in the shape of a covered box in which the lower part of the box shape is open. Specifically, the upper case 20 has a lid surface portion 20a, a side surface portion 20b extending downward from the outer peripheral edge of the lid surface portion 20a to the lower side of the vehicle, and an outer peripheral edge portion 20c connected to the side surface portion 20b. A gas discharge port 18 that communicates the inside and the outside of the battery case 17 is formed on the side surface portion 20b of the upper case 20. The gas discharge port 18 may be formed in the lower case 19.

The lower case 19 and the upper case 20 are made of a metal material such as iron.

The battery 16 is also referred to as a battery module, is mounted on a lower case 19, and is composed of a first battery module 22, a second battery module 23, and a third battery module 24. The first battery module 22, the second battery module 23, and the third battery module 24 have an aggregate structure in which a plurality of battery cells made of a secondary battery (lithium ion battery or the like) are laminated and fixed.

The first battery module 22 is mounted in the vehicle rear side region of the battery storage space 21. The first battery module 22 has a rectangular parallelepiped battery cell having a thin thickness as a constituent unit, and a plurality of battery cells are laminated and fixed in the thickness direction. The first battery module 22 is vertically stacked so that the stacking direction of the battery cells coincides with the vehicle width direction.

The second battery module 23 and the third battery module 24 are mounted on the left and right sides of the battery storage space 21 in the vehicle center region in the vehicle width direction. Similar to the first battery module 22, the second battery module 23 and the third battery module 24 have a thin rectangular parallelepiped battery cell as a constituent unit, and a plurality of battery cells are laminated and fixed in the thickness direction. It was done. The second battery module 23 and the third battery module 24 are mounted in a flat stacking state in which the stacking direction of the battery cells coincides with the vertical direction of the vehicle.

The gas discharge mechanism 12 normally closes the gas discharge port 18, and opens the gas discharge port 18 when the pressure inside the battery case 17 exceeds a predetermined pressure. As the gas discharge mechanism 12, for example, a pressure release valve, a rupture disc (rupture disc), or the like can be used.

The gas discharge member 13 includes a gas discharge space 25 inside. The gas discharge space 25 extends along a predetermined direction and communicates with the inside of the battery case 17 via the gas discharge port 18 and the gas discharge port connection space 26 described later. The gas discharge space 25 is a tubular space that extends at an angle with respect to the extending direction of the gas discharge port connection space 26 and has an opening 27 for gas discharge at one end 25a.

As the gas discharge member 13, for example, a vehicle body skeleton member such as a side member and a side sill extending in the front-rear direction of the vehicle can be used. In the present embodiment, the gas discharge member 13 is composed of a side sill, and a gas discharge space 25 is formed in the internal space of the side sill (see FIG. 6A). As shown in FIG. 6B, an internal wall 28 having a curved surface may be arranged inside the gas discharge member 13. Further, as shown in FIG. 6C, a cylindrical gas discharge member 29 may be arranged instead of the square tubular gas discharge member 13.

The gas discharge member 13 is formed of, for example, a metal material such as iron, similarly to the lower case 19 and the upper case 20 of the battery case 17.

The gas swirling mechanism 14 swirls the gas discharged from the inside of the battery case 17 through the gas discharge port 18 into the gas discharge space 25 in the gas discharge space 25.

The gas swirl imparting mechanism 14 has a gas discharge port connecting member 30. The gas discharge port connection member 30 includes a gas discharge port connection space 26 inside. The gas discharge port connection space 26 extends between the gas discharge port 18 and the gas discharge space 25, and has a tubular shape having one end communicating with the gas discharge port 18 and the other end communicating with the gas discharge space 25. Space. The gas discharge port connection space 26 is arranged on the front side of the vehicle and communicates with the vehicle front side end portion (the other end portion 25b) of the gas discharge space 25. The gas discharge port connection space 26 communicates eccentrically with the gas discharge space 25 inside the gas discharge member 13. That is, the gas discharge port connection space 26 communicates with the gas discharge space 25 at a position deviating from the center of gravity (center of gravity) G of the gas discharge space 25 (see FIG. 6A).

The gas outlet connecting member 30 is made of a metal material such as iron, for example, like the lower case 19 and the upper case 20 of the battery case 17.

The gas swirl imparting mechanism 14 further includes a gas deflection member 31. The gas deflection member 31 is arranged in the gas discharge space 25, and has a surface (flat surface or curved surface) having an angle with respect to the extending direction of the gas discharge port connection space 26. The gas deflection member 31 is arranged at the other end 25b on the opposite side of the one end 25a where the opening 27 is formed in the gas discharge space 25.

The gas deflection member 31 is formed of, for example, a metal material such as iron, similarly to the lower case 19 and the upper case 20 of the battery case 17.

The supply mechanism 15 supplies the oxidation inhibitor into the gas discharge space 25. As the oxidation inhibitor, for example, an inert gas such as nitrogen, carbon dioxide, or argon can be used. Further, as an oxidation inhibitor, an aerosol composition containing a nonflammable volatile liquid such as water, a halogenated hydrocarbon containing a halogen (hydrogen-based halogen compound), and potassium organic carboxylate, potassium acetate, potassium chlorate and the like. You can also use things.

The supply mechanism 15 has a holding portion (oxidation inhibitor holding portion) 32 for holding the oxidation inhibitor. The holding portion 32 has, for example, a wrapping material 33 that covers and holds the oxidation inhibitor, and the oxidation inhibitor is housed inside the wrapping material 33. Further, the oxidation inhibitor inside the wrapping material 33 has a property of expanding due to a chemical reaction due to heat, and when the temperature in the gas discharge space 25 exceeds a predetermined temperature, the wrapping material 33 is expanded by thermal expansion. It is configured to break and open. Such a holding portion 32 is arranged at the other end portion 25b of the gas discharge space 25. Therefore, the supply mechanism 15 supplies the oxidation inhibitor from the other end 25b of the gas discharge space 25 toward the one end 25a (opening 27). In other words, the supply direction of the oxidation inhibitor by the supply mechanism 15 is a direction having an angle with respect to the direction orthogonal to the extending direction of the gas discharge space 25. In other words, the supply direction of the oxidation inhibitor by the supply mechanism 15 is a direction parallel to the extending direction of the gas discharge space 25.

Next, the gas discharge in the battery pack system 10A will be described. In FIG. 4, the flow of gas discharged from the inside of the battery case 17 is indicated by an arrow.

When gas is generated inside the battery case 17 and the internal pressure rises at the time of some abnormality, the gas enters the gas discharge space 25 from the inside of the battery case 17 through the gas discharge port 18 and the gas discharge port connection space 26. Is discharged. The gas discharged into the gas discharge space 25 is given a swirling flow by the gas swirling granting mechanism 14.

The gas swirling in the gas discharge space 25 is from the vehicle front side end portion (the other end portion 25b) of the gas discharge space 25 in a state where the swirling flow is maintained with the extending direction of the gas discharge space 25 as the swivel axis. It flows toward the rear end of the vehicle (one end 25a). Then, the gas in the gas discharge space 25 is discharged to the atmosphere (outside the battery pack system 10A) from the opening 27 formed in the vehicle rear side end portion (one end portion 25a) of the gas discharge space 25.

In order not to obstruct the swirling flow of gas in the gas discharge space 25, the oxidation inhibitor is applied from the vehicle front side end portion (the other end portion 25b) to the vehicle rear side end portion (one end) of the gas discharge space 25. It is supplied toward the portion 25a). The effect of swirling of the gas and the effect of the supply direction of the oxidation inhibitor promotes the mixing of the gas and the oxidation inhibitor. More specifically, when the oxidation inhibitor is supplied from the swirling direction of the gas (the direction orthogonal to the swirling axis of the gas), the gas and the oxidation inhibitor may swirl in a separated state. However, by supplying the oxidation inhibitor from a direction angled with respect to the swirling direction of the gas, mixing of the gas and the oxidation inhibitor is promoted. In the present embodiment, the oxidation inhibitor is supplied from a direction substantially orthogonal to the swirling direction of the gas (parallel to the swirling axis of the gas) to promote mixing of the gas and the oxidation inhibitor. Therefore, the gas is released into the atmosphere through the opening 27 of the gas discharge space 25 in a state where the gas is sufficiently mixed with the oxidation inhibitor. When the gas is sufficiently mixed with the oxidation inhibitor in the gas discharge space 25, the oxidation reaction between the gas released into the atmosphere and the oxygen in the atmosphere is inhibited, and the gas released into the atmosphere becomes hot. Can be suppressed.

The effects of this embodiment will be described below.

(1) The battery pack system 10A includes a battery pack 11 having a battery 16, a battery case 17 for accommodating the battery 16 inside, and a gas discharge port 18 formed in the battery case 17. The battery pack system 10A includes a gas discharge mechanism 12 that normally closes the gas discharge port 18 and opens the gas discharge port 18 when the pressure inside the battery case 17 exceeds a predetermined pressure. The battery pack system 10A includes a gas discharge member 13 including a gas discharge space 25 that extends along a predetermined direction and communicates with the inside of the battery case 17 via the gas discharge port 18. The battery pack system 10A includes a gas swivel granting mechanism 14 for swirling the gas discharged from the inside of the battery case 17 through the gas discharge port 18 into the gas discharge space 25 in the gas discharge space 25, and a gas discharge space 25. A supply mechanism 15 for supplying an oxidation inhibitor is provided therein. The supply direction of the oxidation inhibitor by the supply mechanism 15 is a direction having an angle with respect to the swirling direction of the gas. In the present embodiment, the supply direction of the oxidation inhibitor by the supply mechanism 15 is a direction having an angle with respect to the direction orthogonal to the extending direction of the gas discharge space 25.

The gas discharged from the inside of the battery case 17 flows while swirling in the gas discharge space 25, and the oxidation inhibitor supplied in the gas discharge space 25 also flows while swirling in the gas discharge space 25. .. Here, the oxidation inhibitor is supplied into the gas discharge space 25 from a direction having an angle with respect to the swirling direction of the gas. Therefore, it is possible to promote the mixing of the gas and the oxidation inhibitor, and it is possible to efficiently mix the gas and the oxidation inhibitor.

Therefore, according to the battery pack system 10A, when the oxidation inhibitor is supplied to the gas discharged from the inside of the battery case 17 to the outside, the gas and the oxidation inhibitor are sufficiently mixed to the outside of the battery case 17. The oxidation reaction of the gas in the above can be sufficiently suppressed.

(2) The supply direction of the oxidation inhibitor by the supply mechanism 15 is a direction parallel to the extending direction of the gas discharge space 25.

Since the supply direction of the oxidation inhibitor is parallel to the extending direction of the gas discharge space 25, it is possible to prevent the supply of the oxidation inhibitor from obstructing the gas flow in the gas discharge space 25, and the gas. And the oxidation inhibitor can be efficiently mixed.

(3) The gas swivel granting mechanism 14 has a gas discharge port connecting member 30 internally provided with a gas discharge port connecting space 26 extending between the gas discharge port 18 and the gas discharge space 25. The gas swirling imparting mechanism 14 has a gas deflection member 31 arranged in the gas discharge space 25 and having a surface angled with respect to the extending direction of the gas discharge port connection space 26. The gas discharge space 25 is a tubular space that extends at an angle with respect to the extending direction of the gas discharge port connection space 26 and has an opening 27 for gas discharge at one end 25a.

By configuring the gas swirl imparting mechanism 14 and the gas discharge space 25 in this way, the flow of gas swirling in the gas discharge space 25 is promoted, so that the gas and the oxidation inhibitor can be efficiently mixed. Is possible.

(4) The supply mechanism 15 supplies the oxidation inhibitor toward the opening 27 from the other end 25b on the opposite side of the one end 25a on which the opening 27 is formed in the gas discharge space 25.

By supplying the oxidation inhibitor from the other end 25b in the gas discharge space 25 toward the one end 25a (opening 27), the gas discharge space 25 can be fully utilized, and the gas and the oxidation inhibitor can be fully utilized. And can be efficiently mixed.

(5) The battery pack 11 is arranged under the floor 2 of the electric vehicle 1, and the gas discharge member 13 is composed of a vehicle body skeleton member such as a side member and a side sill extending in the front-rear direction of the vehicle.

By using the vehicle body skeleton members such as side members and side sills, which are indispensable for the electric vehicle 1, as the gas discharge member 13, it is not necessary to arrange new parts in the electric vehicle 1, and it is possible to suppress an increase in manufacturing cost. Is.

[Other Embodiments of the present invention]
As in the battery pack system 10B shown in FIGS. 7 to 9, the gas discharge space 25 and the gas discharge port connection space 26 may be formed in the lower case 19 of the battery pack 11. That is, the gas discharge member 13 and the gas discharge port connection member 30 may be integrally formed in the lower case 19. Also in this case, the gas discharge port connection space 26 is eccentrically communicated with the gas discharge space 25 inside the gas discharge member 13. By doing so, the gas discharged to the gas discharge space 25 through the gas discharge port connection space 26 flows while swirling in the gas discharge space 25.

As in the battery pack system 10C shown in FIG. 10, the inside of the battery pack 11 and the gas discharge space 25 may be connected by a plurality of gas discharge port connection spaces 26 (gas discharge port connection member 30). Also in this case, each gas discharge port connection space 26 is eccentrically communicated with the gas discharge space 25 inside the gas discharge member 13. By doing so, the gas discharged to the gas discharge space 25 through each gas discharge port connection space 26 flows while swirling in the gas discharge space 25.

By the way, the battery pack system of the present invention has been described by taking an example in the above-described embodiment, but the battery pack system is not limited to this embodiment, and various other embodiments can be adopted without departing from the gist of the present invention.

1 Electric vehicle (vehicle)
2 floors (floor panel)
10 Battery pack system 11 Battery pack 12 Gas discharge mechanism 13 Gas discharge member 14 Gas swirl granting mechanism 15 Supply mechanism (oxidation inhibitor supply mechanism)
16 Battery 17 Battery case 18 Gas discharge port 25 Gas discharge space 25a One end 25b The other end 26 Gas discharge port connection space 27 Opening 29 Gas discharge member 30 Gas discharge port connection member 31 Gas deflection member

Claims (3)

A battery, a battery case for accommodating the battery inside, and a battery pack having a gas discharge port formed in the battery case.
A gas discharge mechanism that normally closes the gas discharge port and opens the gas discharge port when the pressure inside the battery case exceeds a predetermined pressure.
A gas discharge member that extends along a predetermined direction and has a gas discharge space inside that communicates with the inside of the battery case through the gas discharge port.
A gas swivel granting mechanism that swirls the gas discharged from the inside of the battery case through the gas discharge port into the gas discharge space in the gas discharge space.
A supply mechanism for supplying an oxidation inhibitor into the gas discharge space is provided.
The gas swirling mechanism has a gas discharge port connecting member having a gas discharge port connection space extending between the gas discharge port and the gas discharge space inside.
The gas discharge space is a cylindrical space that extends at an angle with respect to the extending direction of the gas discharge port connection space and has an opening for gas discharge at one end.
The gas discharge port connection space is communicated with the gas discharge space at a position deviating from the center of gravity of the gas discharge space.
The battery pack system is characterized in that the supply mechanism is arranged at the other end of the gas discharge space opposite to the one end where the opening is formed. The gas swirl imparting mechanism is arranged in front Symbol gas discharge space, characterized in that it have a gas deflection member comprising a surface having an angle with respect to the extending direction of the gas outlet connection space The battery pack system according to claim 1. The battery pack is placed under the floor of the vehicle.
The battery pack system according to claim 1 or 2 , wherein the gas discharge member is composed of a side member extending in the front-rear direction of the vehicle and a vehicle body skeleton member such as a side sill.

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