CN112510284B

CN112510284B - Battery pack with liquid collecting groove

Info

Publication number: CN112510284B
Application number: CN202011266672.9A
Authority: CN
Inventors: 梁其军; 郭盛昌; 魏立群; 肖人漳; 何建; 夏循钊
Original assignee: Chongqing Jinkang Power New Energy Co Ltd
Current assignee: Chongqing Jinkang Power New Energy Co Ltd
Priority date: 2020-11-13
Filing date: 2020-11-13
Publication date: 2022-07-08
Anticipated expiration: 2040-11-13
Also published as: CN112510284A

Abstract

The disclosure belongs to the technical field of battery packs, and particularly relates to a liquid collecting tank of a battery pack, which comprises a spray pipe for spraying a battery module; the device also comprises a liquid collecting tank arranged below the module. Adopt this technical scheme, this scheme is used for holding back the spray liquid through being equipped with the collecting tank in battery module bottom, makes the lower part of battery module can soak in spray liquid, has improved the utilization ratio of coolant liquid, and is good to the cooling effect of battery module, helps putting out a fire.

Description

Battery pack with liquid collecting groove

Technical Field

The disclosure relates to the technical field of battery packs, in particular to a battery pack with a liquid collecting groove.

Background

At present, the safety accidents of the electric vehicle frequently occur, wherein one of the major factors causing the safety accidents of the electric vehicle is the spontaneous combustion of the battery pack. The battery includes battery module and the box that holds battery module, and release high temperature thermal current when battery module takes place thermal runaway, and this high temperature thermal current reveals the back and takes place the burning easily when contacting with the air, and leads to the burning of battery package easily when the thermal current spreads adjacent battery module, brings serious harm for passenger and driver personal safety.

Therefore, the prior art adds a spraying system in the battery pack so as to effectively cope with the thermal runaway phenomenon of the battery pack. However, the fire-retardant liquid sprayed by the spraying system can quickly flow away, the utilization rate of the fire-retardant liquid is low, and the spraying fire-extinguishing effect is poor.

Disclosure of Invention

To above-mentioned problem, this disclosure provides a battery package with collecting tank for hold back spray liquid through set up the collecting tank in battery module bottom. The lower part of the battery module can be soaked in the spraying liquid, the utilization rate of the spraying liquid is improved, the cooling effect is good, and the fire extinguishing is facilitated.

The scheme of the disclosure is as follows:

the battery pack comprises a battery module and a spraying system for spraying the battery module;

the liquid collecting groove is arranged below the battery module.

Preferably, the liquid collecting tank is made of a high-temperature-resistant material which is not easy to deform.

Preferably, the liquid collecting tank is internally provided with a light and high-temperature-resistant filler.

Preferably, the battery module is provided with water-absorbing heat insulation cotton; the side wall of the liquid collecting groove is higher than the lower edge of the water-absorbing heat-insulating cotton.

Preferably, the liquid tank is composed of a box body for accommodating the battery module and a stop block arranged at the bottom of the box body; the bottom of the liquid collecting tank is formed by part of the bottom of the box body; and part of side wall of the box body and the side wall of the stop block form the side wall of the liquid collecting tank.

Preferably, the battery modules comprise an upper layer battery module and a lower layer battery module; the liquid collecting tank comprises a first liquid collecting tank arranged below the upper-layer battery module and a second liquid collecting tank arranged below the lower-layer battery module.

Preferably, the first liquid collecting tank comprises a partition plate arranged below the upper battery module and a side wall arranged at the edge of the partition plate.

Preferably, the second liquid collecting tank is composed of a box body for accommodating the battery module and a stop block arranged at the bottom of the box body; the bottom of the second liquid collecting tank is formed by part of the bottom of the box body; and part of the side wall of the box body and the side wall of the stop block form the side wall of the second liquid collecting tank.

Preferably, the first liquid collecting tank is supported to the lower battery module by a support block.

Preferably, the spraying system comprises a first spraying pipe arranged above the upper-layer battery module and a second spraying pipe arranged above the lower-layer battery module; the second spraying pipe is attached to the bottom of the upper-layer battery module; the partition plate is positioned below the second spraying pipe, a through hole is formed in the bottom of the partition plate relative to the second spraying pipe, and the through hole is sealed by an easily-fused plugging piece.

Preferably, the partition plate is provided with an avoidance groove for accommodating the second spraying pipe; the through hole is formed in the bottom of the avoidance groove; the top of the second spray pipe is flush with the baffle plate.

The battery module bottom of this scheme is equipped with the collecting tank, utilizes the collecting tank to hold back and sprays liquid, and the lower part of battery module can soak in spraying liquid, has improved the utilization ratio of coolant liquid, and is good to the cooling effect of battery module, helps putting out a fire.

Drawings

FIG. 1 is a schematic structural view of the present disclosure;

fig. 2 is a schematic structural view after the battery module is detached;

FIG. 3 is a schematic view of the construction of the first and second sumps;

FIG. 4 is a partial enlarged view at A;

FIG. 5 is a schematic view of a spray system;

FIG. 6 is a schematic view of the first sump configuration;

FIG. 7 is a schematic view of the second sump configuration;

fig. 8 is a schematic structural view of a battery module.

In the figure, a battery module 1, an upper layer battery module 2, a lower layer battery module 3, a box body 4, a water tank 5, a water pump 6, a first spray pipe 7, a second spray pipe 8, a first collecting pipe 9, a second collecting pipe 10, a radiating pipe 11, a third collecting pipe 12, a first collecting tank 13, a side wall 131, a partition plate 132, an avoiding groove 133, a through hole 134, a second collecting tank 14, a stop block 141, a positioning bracket 15, a support lug 16, a liquid supply pipe 17, a return pipe 18, an electromagnetic valve 19, a flow meter 20 and heat insulation cotton 21.

Detailed Description

The following is further detailed by the specific embodiments:

as shown in fig. 1, a battery pack for an automobile includes an upper battery module 2, a lower battery module 3, a cooling system, and a spray system.

In this embodiment, the upper layer battery module 2 and the lower layer battery module 3 each include a plurality of battery modules 1. The upper layer battery module 2 and the lower layer battery module 3 are both installed in the box body 4. The lower battery module 3 is attached to the bottom of the box body 4 through the heat conducting sheet.

The cooling system comprises a water tank 5 for storing cooling liquid, and a water outlet is formed in the lowest position of the water tank 5, so that the cooling liquid in the water tank 5 can flow out completely. The upper part of the water tank 5 is provided with a reflux opening for the cooling liquid to flow back to the water tank 5. The cooling fluid is 50% glycol in some embodiments, which has good fluidity and high thermal conductivity. The cooling system comprises a power device, and the power device selects a water pump 6 to improve power for the flowing of cooling liquid.

As shown in fig. 2, the cooling system further includes a first header 9, a second header 10, and a plurality of parallel cooling pipes; the cooling pipe is provided between the upper layer battery module 2 and the lower layer battery module 3. The top of each cooling pipe carries out heat dissipation and cooling on each row/column of battery modules 1 of the upper battery module 2; the water inlet ends of the cooling pipes are connected to the first collecting pipe 9, and the first collecting pipe 9 divides the cooling liquid into the cooling pipes; the water outlet ends of the cooling pipes are connected to the second collecting pipe 10, and the second collecting pipe 10 converges the cooling liquid and delivers the cooling liquid to the water tank 5 through the return pipe 18.

Through setting up the cooling tube between upper battery module 2 and lower floor's battery module 3, utilize the cooling tube to carry out cooling to upper battery module 2, the heat that upper battery module 2 produced distributes through the cooling tube, avoids taking place the thermal runaway because of upper battery module 2's heat gathering, improves the security of battery package.

The cooling system further includes a radiating pipe 11 attached to the case 4. The cross section of the radiating pipe 11 is rectangular, the bottom of the radiating pipe 11 is attached to the bottom of the box body 4, and one side wall of the radiating pipe 11 is attached to the inner side wall of the box body 4. The radiating pipe 11 is attached to the surface of the box body 4, and radiating fins are extended on the surface of the box body 4, so that the contact area between the radiating pipe 11 and the box body 4 is increased through the radiating fins, and the radiating effect of the box body 4 is enhanced. One end of the radiating pipe 11 is connected to the first collecting pipe 9, and the other end is connected to the water outlet of the water tank 5 through the water supply pipe 17.

As shown in fig. 5, in the present embodiment, the shower system includes a plurality of first shower pipes 7 provided above the upper layer battery module 2 and a plurality of second shower pipes 8 provided above the lower layer battery module 3.

Each first spraying pipe 7 is arranged relative to the explosion-proof valve of each row/column of battery modules 1 of the upper-layer battery module, the part of the first spraying pipe 7, which is at least opposite to the explosion-proof valve, is heated to form an opening, and one end of each first spraying pipe 7 is connected to the third collecting pipe 12 in parallel for cooling liquid to flow in; the other end of the first spray pipe 7 is blocked. The third header 12 is connected to the first header 9.

In this embodiment, the cooling pipe also serves as the second shower pipe 8, each second shower pipe 8 is provided with respect to the explosion-proof valve of each row/column of the battery modules 1 of the lower battery module 3, and at least a portion of the second shower pipe 8 facing the explosion-proof valve is easily opened by heat. In this embodiment, the opening formed by heating means that when thermal runaway occurs, the flame easily burns through the shower pipe to form an opening for spraying the cooling liquid.

In some embodiments, the first shower pipe 7 and the second shower pipe 8 may also be selected from serpentine pipes, and due to the defects of low structural strength, large flow resistance, slow response speed, etc., the foregoing manner of multiple shower pipes is preferred in this embodiment.

In order to reduce the installation space of the first spray pipe 7 and the second spray pipe 8 and facilitate the capture of flame to the first spray pipe 7 and the second spray pipe 8, the first spray pipe 7 and the second spray pipe 8 in the embodiment are preferably flat pipes and preferably made of aluminum, so that the first spray pipe 7 has good thermal conductivity and the cooling effect of the upper battery module 2 is ensured; and the first spray pipe 7 and the second spray pipe 8 made of aluminum have low melting points and are easy to be heated to form openings in a thermal runaway environment.

In this embodiment, for avoiding spraying the liquid that sprays on upper battery module 2 and the lower floor's battery module 3 and run off fast, as shown in fig. 3, be equipped with first collecting tank 13 in upper battery module 2 bottom, lower floor's battery module 3 bottom is equipped with second collecting tank 14, first collecting tank 13 and second collecting tank 14 are used for holding back the liquid that sprays, make upper battery module 2 and lower floor's battery module 3 lower part can soak in the liquid that sprays, the utilization ratio of coolant liquid has been improved, good to the cooling effect of battery module, help putting out a fire.

In the embodiment, the first liquid collecting tank and the second liquid collecting tank are both made of materials which are high temperature resistant and difficult to deform, such as iron, aluminum and the like; the high temperature resistance and the deformation resistance in the present embodiment mean that the alloy does not melt and deform at an ambient temperature of 100 ℃.

As shown in fig. 6, the first catch tank 13 includes a partition plate 132 disposed below the second shower pipe 8 and a side wall 131 disposed at an edge of the partition plate 132; partition 132 forms a recessed relief groove 133 relative to second shower 8, relief groove 133 being configured to receive second shower 8 such that the top of second shower 8 is flush with partition 132. Avoid shower protrusion in first collecting tank 13 bottom, conveniently install battery module 1 in first collecting tank 13, the bottom laminating of the second shower 8 and upper battery module 2 of being convenient for.

In this embodiment, a through hole 134 is formed at the bottom of the avoiding groove 133, and the through hole 134 is sealed by a fusible sealing member. In this embodiment, the through-hole 134 is preferably sealed with an aluminum foil tape. When thermal runaway occurs, the flame can conveniently burn through the aluminum foil tape to expose the through hole 134. Flame passes through the through hole 134 to ignite the second spray pipe 8, so that an opening is formed on the second spray pipe 8, and the lower-layer battery module 2 is sprayed and extinguished.

As shown in fig. 7, the second sump 14 is composed of a bottom of the case 4 and a stopper 141 provided at the bottom of the case 4, a part of the bottom of the case 4 constitutes a bottom of the second sump 14, and a part of the side walls of the case 4 and the side walls of the stopper 141 enclose the side walls of the second sump 14, which is simple in structure.

In some embodiments, the second liquid collecting tank 14 may be directly formed at the lower portion of the case 4, and since the space at the lower portion of the case 4 is large, the liquid level of the spray liquid at the bottom of the case 4 is low, and the cooling effect on the lower battery module 2 is poor, the second liquid collecting tank 14 with the stopper 141 is preferably used in this embodiment.

In this embodiment, the empty spaces between the bottoms of the first and second

liquid collecting grooves

13 and 14 and the bottom of the battery module are filled with light and high-temperature-resistant filler, so as to increase the effective height of the liquid contacting the battery module. The filler in this embodiment is preferably a cotton filler having a heat insulating effect.

As shown in fig. 3 and 4, the bottom of the first liquid collecting tank 13 abuts against the lower battery module 3 through a support block (not shown), and is fixed by bolts. Two vertical positioning brackets 15 are arranged on the stopper 141; the positioning bracket 15 is a vertically arranged metal strip, and the top and the bottom of the positioning bracket 15 form horizontal folded edges. The hem at the bottom is welded on the stop block 141, and the hem at the top is provided with a first positioning hole. The side wall 131 is provided with a support lug 16 relative to the positioning bracket 15, and the support lug 16 is right-angled; the vertical surface of the support lug 16 is welded on the side wall 131, and a second positioning hole is formed on the horizontal surface of the support lug 16 relative to the first positioning hole. In the installation process, the first liquid collecting tank 13 is matched with the first positioning hole through the second positioning hole, and positioning pins are arranged in the first positioning hole and the second positioning hole in a penetrating mode, so that the installation precision is guaranteed.

As shown in fig. 8, in the embodiment, the thermal insulation cotton 21 is wrapped on both sides of the battery module 1, the thermal conductivity of the thermal insulation cotton 21 is small, so that not only can the thermal runaway phenomenon be prevented from diffusing, but also the thermal insulation cotton 21 has water absorption, so that sprayed coolant can be absorbed, and temperature reduction and fire prevention can be realized. The heat insulation cotton 21 has good heat insulation effect, and the battery pack can adapt to low-temperature environment.

In this embodiment, the heat insulation cotton 21 is used in cooperation with the first liquid collecting tank 13 or the second liquid collecting tank 14, and the heat insulation cotton 21 can sufficiently absorb the coolant collected by the first liquid collecting tank 13 or the second liquid collecting tank 14, so that the cooling effect is better.

In this embodiment, the lower edge that is higher than thermal-insulated cotton 21 of the lateral wall of first collecting tank 13 and second collecting tank 14 or the curb plate that is higher than the battery module, thermal-insulated cotton 21 can absorb the liquid that sprays, forms the state that the liquid that sprays surrounds electric core, battery module to increase the area of contact of the liquid that sprays with electric core, battery module, improve cooling efficiency. The height of the side walls of the first sump 13 and the second sump 14 in this embodiment is not less than 1 mm. Also, a plurality of small compartments, each capable of accommodating a single or a plurality of battery modules, may be provided in the first and

second sumps

13 and 14 in this embodiment.

In this embodiment, a solenoid valve 19 is installed on the return pipe 18, and a water pump 6 and a flow rate meter 20 are installed on the supply pipe 17. The solenoid valve 19, the water pump 6 and the flow rate meter 20 are all electrically connected to the BMS control system.

When the battery pack normally works, the solenoid valve 19 is normally opened, and the cooling fluid in the water tank 5 flows into the first collecting main 9 through the fluid supply pipe 17 and the radiating pipe 11 in sequence. A part of the cooling liquid in the first collecting pipe 9 sequentially passes through the cooling pipe, the second collecting pipe 10 and the return pipe 18 and then flows back to the water tank 5; another portion of the cooling fluid flows into the shower pipe through the third header 12. BMS control system adjusts the flow of coolant liquid through the power of control water pump 6, satisfies the cooling demand of not equidimension, and the cooling effect is good.

When thermal runaway occurs, the solenoid valve 19 is controlled to be closed by the BMS control system, and the connection between the return pipe 18 and the water tank 5 is cut off by the solenoid valve 19. Flame that upper battery module 2 generated spouts through explosion-proof valve is upwards, the first shower 7 of firing makes first shower 7 form the opening, sprays to upper battery module 2 and puts out a fire. The first liquid collecting tank 13 collects the cooling liquid sprayed by the first spraying pipe 7, so that the lower part of the upper-layer battery module is soaked in the cooling liquid to cool the upper-layer battery module 2.

The flame that lower floor's battery module 3 generated upwards spouts through the explosion-proof valve, and the aluminium foil adhesive tape on the baffle 132 that burns out earlier of flame spills through-hole 134, then burns second shower 8 through-hole 134, makes to form the opening on the second shower 8, sprays to put out a fire lower floor's battery module 3. The second liquid collecting tank 14 collects the cooling liquid sprayed by the second spraying pipe 8, so that the lower part of the lower-layer battery module is soaked in the cooling liquid to cool the lower-layer battery module 3. The utilization rate of the cooling liquid is improved, and the fire extinguishing effect is ensured.

In the present embodiment, when the electromagnetic valve 19 is closed, the water tank 5 continues to supply the cooling liquid, and the pressure in the first shower pipe 7 and the second shower pipe 8 gradually increases. The first spraying pipe 7 and the second spraying pipe 8 can only release pressure through the opening, and the pressure of the cooling liquid is high, so that the fire extinguishing effect is enhanced.

In the spraying and fire extinguishing process, the BMS control system can detect the flow rate of the cooling liquid through the flow rate regulating meter 20, and when the flow rate is too large, the BMS control system sends an instruction to reduce the power of the water pump 6 and reduce the flow rate of the cooling liquid. When the velocity of flow is too little, BMS control system sends the instruction and improves the power of water pump 6, promotes the velocity of flow of coolant liquid, realizes accurate control. The phenomenon of thermal runaway can be effectively solved by avoiding the too fast consumption or insufficient supply of the cooling liquid.

In some embodiments, the battery pack has only one layer of battery modules, and the structure of the liquid collecting groove below the battery modules is the same as that of the second liquid collecting groove. Although the box of battery package has a collection liquid function, the box of battery package is not equivalent to the collecting tank in this embodiment, because the area of bottom half is great, the liquid level of the coolant liquid in the box is low, and the lower part of battery module can't soak in the coolant liquid of collection, and the cooling effect is poor. The liquid collecting tank in this embodiment can guarantee that the coolant liquid has higher liquid level, and the cooling is effectual.

The disclosure is not limited solely to that described in the specification and the embodiments, and thus additional advantages and modifications may readily occur to those skilled in the art, and it is not intended to be limited to the specific details, representative apparatus, and illustrative examples shown and described herein, without departing from the spirit and scope of the general concept as defined by the appended claims and their equivalents.

Claims

1. The battery pack comprises a battery module and a spraying system for spraying the battery module;

the battery module comprises an upper layer battery module and a lower layer battery module;

the method is characterized in that:

the upper layer battery module and the lower layer battery module are provided with water-absorbing heat insulation cotton;

the liquid collecting grooves comprise a first liquid collecting groove arranged below the upper-layer battery module and a second liquid collecting groove arranged below the lower-layer battery module;

the side walls of the first liquid collecting groove and the second liquid collecting groove are higher than the lower edge of the water-absorbing heat-insulating cotton;

the first liquid collecting groove comprises a partition plate arranged below the upper-layer battery module and a side wall arranged at the edge of the partition plate;

the spraying system comprises a first spraying pipe arranged above the upper-layer battery module and a second spraying pipe arranged above the lower-layer battery module; the second spraying pipe is attached to the bottom of the upper-layer battery module;

the partition plate is positioned below the second spray pipe, the bottom of the partition plate is provided with a through hole relative to the second spray pipe, and the through hole is sealed by a fusible plugging piece;

the partition plate is provided with an avoiding groove for accommodating the second spraying pipe; the through hole is formed in the bottom of the avoidance groove; the top of the second spray pipe is flush with the baffle plate.

2. The battery pack having a sump according to claim 1, wherein: the first liquid collecting tank and the second liquid collecting tank are made of high-temperature-resistant materials which are not easy to deform.

3. The battery pack having a sump according to claim 2, wherein: and light and high-temperature-resistant fillers are arranged in the first liquid collecting tank and the second liquid collecting tank.

4. The battery pack having the sump according to claim 3, wherein: the second liquid collecting tank consists of a box body for accommodating the battery module and a stop block arranged at the bottom of the box body; the bottom of the second liquid collecting tank is formed by part of the bottom of the box body; and part of side walls of the box body and side walls of the stop block form side walls of the second liquid collecting tank.

5. The battery pack having the sump according to claim 4, wherein: the first liquid collecting groove is supported on the lower layer battery module through a supporting block.

6. The battery pack having a sump according to claim 5, wherein: a plurality of small separation grooves are formed in the first liquid collection groove and the second liquid collection groove, and each small separation groove can accommodate a single battery module or a plurality of battery modules.