阅读说明：本技术 一种动力电池热流泄放装置及动力电池热流泄放方法 (Power battery heat flow discharge device and power battery heat flow discharge method ) 是由 孙士杰 孙焕丽 乔延涛 刘鹏 陈雷 耿宇明 于 2020-12-25 设计创作，主要内容包括：本发明属于电动车技术领域,公开了一种动力电池热流泄放装置及动力电池热流泄放方法。该动力电池热流泄放装置包括：电池箱,其用于容纳电芯,在电池箱的侧面设置有防爆阀；在隔离机构内设置有引流流道和主流道,在引流流道靠近电芯的一侧设置有引流界面,引流界面与电芯的泄压阀正对设置并与其选择性连通,在隔离机构的侧面设置有排气孔,排气孔与防爆阀正对设置并与其相连通；引流流道、主流道、排气孔依次连通,形成泄放流道,使从电芯的泄压阀流出的高压气体能够通过引流界面进入引流流道内,并通过主流道经排气孔后从防爆阀排出。该动力电池热流泄放装置延缓动力电池内热失控的扩散,保护车内乘员安全,最大限度降低损失。(The invention belongs to the technical field of electric vehicles, and discloses a power battery heat flow discharge device and a power battery heat flow discharge method. This power battery thermal current bleeder mechanism includes: the battery box is used for accommodating the battery core, and an explosion-proof valve is arranged on the side surface of the battery box; a drainage flow channel and a main flow channel are arranged in the isolation mechanism, a drainage interface is arranged on one side of the drainage flow channel close to the battery core, the drainage interface is arranged opposite to and selectively communicated with a pressure release valve of the battery core, and an exhaust hole is arranged on the side surface of the isolation mechanism and opposite to and communicated with an explosion-proof valve; the drainage flow channel, the main flow channel and the exhaust holes are communicated in sequence to form a discharge flow channel, so that high-pressure gas flowing out of the pressure release valve of the battery core can enter the drainage flow channel through the drainage interface and is discharged from the explosion-proof valve through the main flow channel after passing through the exhaust holes. The heat flow release device of the power battery delays the diffusion of thermal runaway in the power battery, protects the safety of passengers in the vehicle and reduces the loss to the maximum extent.)

1. A power battery heat flow relief device, characterized by, includes:

the battery box (1) is used for accommodating the battery core (100), and an explosion-proof valve (13) is arranged on the side surface of the battery box (1);

the isolating mechanism (2) is arranged above the battery cell (100), a drainage flow channel (211) and a main flow channel (212) are arranged in the isolating mechanism (2), a drainage interface (213) is arranged on one side, close to the battery cell (100), of the drainage flow channel (211), the drainage interface (213) is opposite to and selectively communicated with a pressure release valve of the battery cell (100), the section of the drainage flow channel (211) is gradually increased along the direction far away from the battery cell (100), an exhaust hole (214) is arranged on the side face of the isolating mechanism (2), the exhaust hole (214) is opposite to and communicated with the explosion-proof valve (13), and the section of the main flow channel (212) is gradually increased along the direction close to the exhaust hole (214);

drainage runner (211), sprue (212) exhaust hole (214) communicate in proper order, form the discharge runner, make follow the high-pressure gas that the relief valve of electricity core (100) flows can pass through drainage interface (213) gets into in drainage runner (211), and pass through sprue (212) process follow behind exhaust hole (214) explosion-proof valve (13) discharge.

2. The power battery heat flow bleeder device according to claim 1, wherein the isolating mechanism (2) comprises an isolating piece (21) and an isolating upper cover (22), an opening is arranged on one side of the isolating piece (21) far away from the battery core (100), the isolating upper cover (22) is blocked at the opening, the isolating piece (21) is arranged above the battery core (100), and the drainage flow channel (211) and the main flow channel (212) are formed between the isolating piece (21) and the isolating upper cover (22).

3. The power battery heat flow bleeder device according to claim 2, wherein a limiting portion (23) is convexly provided at one side of the isolating member (21) close to the explosion-proof valve (13), the limiting portion (23) is disposed at an outer side surface of the battery core (100), a limiting groove is provided in the battery box (1) corresponding to the limiting portion (23), and the limiting portion (23) is disposed in the limiting groove.

4. The power battery heat flow relief device according to claim 3, wherein a communication channel (231) is provided in the limiting portion (23), and the main flow channel (212) is communicated with the exhaust hole (214) through the communication channel (231).

5. The power cell heat flow bleeder device according to claim 2, wherein the isolating means (2) further comprises a seal disposed between the isolator (21) and the isolating upper cover (22).

6. The power battery heat flow relief device according to claim 5, wherein the drainage flow channel (211) and the main flow channel (212) are both sealed cavity structures.

7. The power battery heat flow relief device according to claim 2, wherein the isolating upper cover (22) is made of mica material.

8. The power battery heat flow relief device according to claim 2, characterized in that the spacer (21) is made of SMC composite material.

9. The power cell heat flow drain of claim 1, wherein a wall thickness of the drain interface (213) is less than a wall thickness of the drain flow channel (211).

10. A power battery thermal flow relief method for controlling the power battery thermal flow relief device according to any one of claims 1 to 9, the power battery thermal flow relief method comprising the steps of:

setting a preset opening pressure of a drainage interface (213) according to the valve opening impact force of the pressure release valve when the battery cell (100) is out of control due to heat;

if the actual pressure of the high-temperature gas generated by the thermal runaway of the battery cell (100) is greater than the preset opening pressure, the high-temperature gas breaks through the drainage interface (213) and enters the drainage flow channel (211);

the high-temperature gas flows into the main flow passage (212) through the drainage flow passage (211);

if the pressure of the high-temperature gas flowing out of the exhaust hole (214) is greater than the preset pressure of the explosion-proof valve (13), the high-temperature gas is exhausted through the explosion-proof valve (13).

Technical Field

The invention relates to the technical field of electric vehicles, in particular to a power battery heat flow discharging device and a power battery heat flow discharging method.

Background

The power battery used by the electric vehicle is generally a lithium battery, and the lithium battery has the risk of thermal runaway under the conditions of short circuit, overcharge and overdischarge, temperature overrun, mechanical damage and the like. With the increasing use amount of electric vehicles, thermal runaway accidents are frequent, and the safety problem of the electric vehicles becomes a hot spot of social attention.

Along with the continuous promotion of electric core energy density, lithium cell thermal runaway's danger also is increasing constantly. Because the power battery pack for the vehicle is a relatively closed space, a large amount of heat can be released by thermal runaway of a single battery cell, and then linkage thermal runaway of other battery cells in the battery pack is triggered.

At present, a fire-retardant device such as a fire-proof plate is only arranged inside a battery pack of a power battery so as to delay the diffusion speed of open fire to the outside of the power battery pack, but the spread of thermal runaway in the battery pack cannot be prevented, and the thermal runaway in a battery pack system is diffused, so that the safety of passengers in a vehicle is influenced.

Disclosure of Invention

The invention aims to provide a power battery heat flow discharge device and a power battery heat flow discharge method, which can delay the diffusion of thermal runaway in a battery pack system, protect the safety of passengers in a vehicle and reduce loss.

In order to achieve the purpose, the invention adopts the following technical scheme:

a power battery thermal flow relief device, comprising:

the battery box is used for accommodating the battery core, and an explosion-proof valve is arranged on the side surface of the battery box;

the isolation mechanism is arranged above the battery cell, a drainage flow channel and a main flow channel are arranged in the isolation mechanism, a drainage interface is arranged on one side, close to the battery cell, of the drainage flow channel, the drainage interface is arranged opposite to a pressure release valve of the battery cell and is selectively communicated with the pressure release valve of the battery cell, the section of the drainage flow channel is gradually increased along the direction far away from the battery cell, an exhaust hole is arranged on the side face of the isolation mechanism, the exhaust hole is arranged opposite to the explosion-proof valve and is communicated with the explosion-proof valve, and the section of the main flow channel is gradually increased along the direction close to the exhaust hole;

the drainage flow channel, the main flow channel and the exhaust holes are sequentially communicated to form a discharge flow channel, so that high-pressure gas flowing out of the pressure release valve of the battery cell can enter the drainage flow channel through the drainage interface and is discharged from the explosion-proof valve through the main flow channel after passing through the exhaust holes.

Preferably, the isolation mechanism includes an isolation piece and an isolation upper cover, an opening is provided at a side of the isolation piece away from the battery cell, the isolation upper cover is plugged in the opening, the isolation piece is disposed above the battery cell, and the drainage channel and the main channel are formed between the isolation piece and the isolation upper cover.

Preferably, one side of the isolating piece, which is close to the explosion-proof valve, is convexly provided with a limiting part, the limiting part is arranged on the outer side surface of the battery core, a limiting groove is arranged in the battery box corresponding to the limiting part, and the limiting part is arranged in the limiting groove.

Preferably, a communication flow passage is provided in the stopper portion, and the main flow passage is communicated with the exhaust hole through the communication flow passage.

Preferably, the isolation mechanism further comprises a sealing member disposed between the isolation member and the isolation upper cover.

Preferably, the drainage channel and the main channel are both of a sealed cavity structure.

Preferably, the isolation upper cover is made of mica material.

Preferably, the spacer is made of SMC composite material.

Preferably, the wall thickness of the drainage interface is smaller than the wall thickness of the drainage flow channel.

In order to achieve the above object, the present invention further provides a power battery thermal flow discharging method for controlling the above power battery thermal flow discharging device, where the power battery thermal flow discharging method includes the following steps:

setting a preset opening pressure of a drainage interface according to the valve opening impact force of the pressure release valve when the battery core is out of control due to heat;

if the actual pressure of the high-temperature gas generated by the thermal runaway of the battery cell is greater than the preset opening pressure, the high-temperature gas breaks through the drainage interface and enters the drainage flow channel;

the high-temperature gas flows into the main flow channel through the drainage flow channel;

if the pressure of the high-temperature gas flowing out of the exhaust hole is greater than the preset pressure of the explosion-proof valve, the high-temperature gas is exhausted through the explosion-proof valve.

The invention has the beneficial effects that:

according to the power battery heat flow discharge device provided by the invention, the drainage interface is arranged on one side of the drainage flow channel, which is close to the battery core, and is opposite to and selectively communicated with the pressure release valve of the battery core, so that high-pressure gas flowing out of the pressure release valve of the battery core can enter the drainage flow channel through the drainage interface after breaking the drainage interface, the drainage flow channel plays a drainage role, the main flow channel is communicated with the drainage flow channel, the main flow channel plays a role of collecting the drainage flow channel, and the exhaust holes are respectively communicated with the main flow channel and the explosion-proof valve, so that the high-pressure gas is exhausted from the explosion-proof valve through the main flow channel after passing through the exhaust holes, under the condition of thermal runaway of a battery module, the thermal runaway diffusion of the power battery is delayed, the. Compared with the prior art, this power battery thermal current bleeder mechanism's drainage runner, sprue, exhaust hole communicate in proper order, form the runner of bleeding, outside the high-temperature gas with the thermal runaway release derives the battery module rapidly, through setting up isolation mechanism, keeps apart high-temperature gas and electric core, restraines battery module heat diffusion.

The cross-section of drainage runner increases along the direction of keeping away from electric core gradually, and the drainage runner adopts the mode that expands gradually, increases the flow area of blowout high temperature gas, reduces the flow speed, reduces the impact of air current to keeping apart the upper cover, has played the effect to keeping apart the upper cover protection.

The cross-section of sprue increases along the direction that is close to the exhaust hole gradually, and the sprue adopts the mode of gradually expanding, and the front end of sprue, sprue promptly to exhaust hole flow area increase gradually to reduce air velocity, according to Bernoulli's principle, flow velocity reduces and can lead to pressure to rise, in order to increase exhaust hole department pressure, open as early as possible in order to do benefit to explosion-proof valve, in time exhaust, in order to reach the purpose of restraining the heat diffusion.

According to the power battery heat flow discharge method provided by the invention, the preset opening pressure of the drainage interface is set according to the valve opening impact force of the pressure release valve when the battery core is out of control due to thermal runaway, and it can be understood that the wall thickness of the drainage interface is set, so that the impact force of the battery core pressure release valve can sufficiently break the drainage interface when the battery core is out of control due to thermal runaway, high-temperature gas can conveniently break the drainage interface, enter the drainage flow channel, flow out of the exhaust hole through the main flow channel and then be discharged by the explosion-proof valve, the power battery heat flow discharge method is used for delaying the diffusion of out of control due to thermal runaway in a battery.

Drawings

FIG. 1 is a schematic diagram of a partial explosion of a thermal flow relief device for a power cell in accordance with the present invention;

fig. 2 is an exploded view of an isolation mechanism in the thermal flow relief device of a power battery of the present invention;

fig. 3 is a schematic structural diagram of a drainage interface in the thermal flow relief device of the power battery of the present invention;

fig. 4 is a schematic structural diagram of a drainage flow channel in the thermal flow relief device for a power battery of the invention;

fig. 5 is a schematic structural diagram of a main flow channel in the heat flow relief device for the power battery of the invention.

In the figure:

100. an electric core;

1. a battery box; 2. an isolation mechanism;

11. a housing; 12. an upper cover of the battery; 13. an explosion-proof valve;

21. a spacer; 22. an isolating upper cover; 23. a limiting part;

211. a drainage flow channel; 212. a main flow channel; 213. a drainage interface; 214. an exhaust hole;

231. and the flow passage is communicated.

Detailed Description

In order to make the technical problems solved, technical solutions adopted and technical effects achieved by the present invention clearer, the technical solutions of the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.

The embodiment provides a power battery heat flow discharge device, as shown in fig. 1, the power battery heat flow discharge device includes a battery box 1, the battery box 1 includes a housing 11 and a battery upper cover 12, one side of the housing 11 is provided with an opening, the battery upper cover 12 closes the opening of the housing 11, a battery core 100 can be placed into the opening of the housing 11, the housing 11 of the battery box 1 is used for accommodating the battery core 100, and an explosion-proof valve 13 is arranged on a side surface of the housing 11 in the battery box 1 and used for discharging heat generated by the battery core 100. It can be understood that the number of the battery cells 100 may be multiple, in this embodiment, the number of the battery cells 100 is preferably four, and four battery cells 100 are distributed according to a two-row and two-column rectangular array structure to form a battery module.

As a large amount of heat is released by a single battery cell 100 due to thermal runaway, and then chain thermal runaway of other battery cells 100 is caused, in order to solve the problem, as shown in fig. 1-2, the power battery thermal flow discharge device further includes an isolation mechanism 2, the isolation mechanism 2 is disposed above the battery cell 100, a drainage flow channel 211 and a main flow channel 212 are disposed in the isolation mechanism 2, a drainage interface 213 is disposed on one side of the drainage flow channel 211 close to the battery cell 100, the drainage interface 213 is directly opposite to and selectively communicated with a pressure release valve of the battery cell 100, and it can be understood that each battery cell 100 corresponds to one drainage interface 213. An exhaust hole 214 is formed in the side surface of the isolation mechanism 2, and the exhaust hole 214 is arranged opposite to and communicated with the explosion-proof valve 13. The drainage flow channel 211, the main flow channel 212 and the exhaust hole 214 are sequentially communicated to form a discharge flow channel, so that the airflow flowing out of the pressure release valve of the battery cell 100 can enter the drainage flow channel 211 through the drainage interface 213 and is discharged from the explosion-proof valve 13 through the main flow channel 212 and the exhaust hole 214.

The thermal flow discharging device for the power battery provided by the embodiment is provided with the drainage interface 213 on one side of the drainage channel 211 close to the battery core 100, the drainage interface 213 is opposite to and selectively communicated with the pressure release valve of the battery core 100, so that high-pressure gas flowing out from the pressure release valve of the battery core 100 breaks through the drainage interface 213 and can enter the drainage channel 211 through the drainage interface 213, the drainage channel 211 plays a role of drainage, the main channel 212 is communicated with the drainage channel 211, the main channel 212 plays a role of collecting the drainage channel 211, the exhaust holes 214 are respectively communicated with the main channel 212 and the explosion-proof valve 13, so that the high-pressure gas is exhausted from the explosion-proof valve 13 through the main channel 212 via the exhaust holes 214, under the condition that thermal runaway of the battery module occurs, the thermal runaway diffusion in the power battery is delayed, the safety of passengers in the vehicle is. Compared with the prior art, this power battery heat flow bleeder device's drainage runner 211, sprue 212, exhaust hole 214 communicate in proper order, form the runner of bleeding, lead out the high-temperature gas of thermal runaway release outside the battery module rapidly, through setting up isolation mechanism 2, keep apart high-temperature gas and electric core 100, restrain battery module heat diffusion.

Further, as shown in fig. 2, the isolation mechanism 2 includes a partition 21 and an isolation upper cover 22, an opening is provided at a side of the partition 21 away from the battery cell 100, the isolation upper cover 22 is sealed in the opening, the partition 21 is provided above the battery cell 100, and a drainage channel 211 and a main channel 212 are formed between the partition 21 and the isolation upper cover 22. Preferably, the isolating cover 22 is detachably coupled to the isolating member 21, facilitating the installation and removal of the isolating cover 22.

Wherein, keep apart upper cover 22 and adopt mica material to make, keep apart upper cover 22 and make by mica for keep apart upper cover 22's mechanical strength is high, and high temperature resistant is effectual, and thermal runaway impact force can't break through and keep apart upper cover 22, and intensity is good. The isolating piece 21 is made of SMC composite material, the SMC composite material has small heat conductivity coefficient, the isolation between high-temperature gas and the battery cell 100 can be realized, the heat diffusion is delayed, the heat exchange between the isolating piece 21 and the battery cell 100 is avoided, and the condition that the high-temperature gas in the discharging flow channel in the isolating piece 21 reversely heats the battery cell 100 is caused.

It will be appreciated that the material of the isolating cover 22 is not limited to mica, but may be replaced by a material that performs the same function. The material of the spacer 21 is not limited to the SMC composite material, and may be replaced by a material that can achieve the same function.

Further, the isolation mechanism 2 further includes a sealing member disposed between the isolation member 21 and the isolation upper cover 22. The sealing element can be a sealing ring or a sealant, and the sealing element is arranged between the isolation element 21 and the isolation upper cover 22, so that the isolation element 21 and the isolation upper cover 22 are in sealing adhesion, and the sealing effect between the isolation element 21 and the isolation upper cover 22 is ensured. It can be understood that, because the partition 21 and the partition upper cover 22 are in sealed connection, the drainage channel 211 and the main channel 212 are both in a sealed cavity structure, so as to avoid the leakage of high-temperature gas in the flowing process.

In order to ensure the fixing effect of the isolating piece 21 in the battery box 1, a limiting portion 23 is convexly arranged on one side of the isolating piece 21 close to the explosion-proof valve 13, the limiting portion 23 extends towards the direction close to the battery cell 100, the limiting portion 23 is arranged on the outer side surface of the battery cell 100, a limiting groove is arranged in the battery box 1 corresponding to the limiting portion 23, and the limiting portion 23 is arranged in the limiting groove. Through mutually supporting of spacing portion 23 and spacing groove to spacing to 21, avoid 21 to appear the position removal in battery box 1, structural stability is good.

Because the limiting part 23 is disposed between the partition 21 and the explosion-proof valve 13, in order to ensure smooth discharge of the high-temperature gas, a communication flow channel 231 is disposed in the limiting part 23, and the main flow channel 212 is communicated with the exhaust hole 214 through the communication flow channel 231, so that the high-temperature gas in the main flow channel 212 flows out of the exhaust hole 214 after passing through the communication flow channel 231.

Further, as shown in fig. 3, the wall thickness of the drainage interface 213 is smaller than the wall thickness of the drainage channel 211. The drainage interface 211 adopts a local wall thickness weakening mode, so that high-temperature gas generated by the battery cell 100 can break through the drainage interface 211 when the battery cell 100 is out of control due to heat, the selective opening effect of the drainage interface 211 is realized, and the high-temperature gas can conveniently enter the drainage flow channel 211.

Further, as shown in fig. 4, the cross section of the drainage flow channel 211 gradually increases along the direction away from the battery cell 100, and the drainage flow channel 211 increases the flow area of the ejected high-temperature gas in a gradually expanding manner, reduces the flow speed, reduces the impact of the airflow on the isolation upper cover 22, and plays a role in protecting the isolation upper cover 22.

Further, as shown in fig. 5, the cross section of the main flow channel 212 gradually increases along the direction close to the exhaust hole 214, the main flow channel 212 adopts a gradually expanding mode, the front end of the main flow channel 212, that is, the side of the main flow channel 212 close to the exhaust hole 214, the flow area of the main flow channel 212 towards the exhaust hole 214 gradually increases to reduce the air flow velocity, and according to the bernoulli principle, the reduction of the flow velocity can cause the pressure to rise to increase the pressure at the exhaust hole 214, so as to facilitate the explosion-proof valve 13 to open as soon as possible, and exhaust in time, so as to achieve the purpose of suppressing heat diffusion.

The embodiment also provides a power battery heat flow discharging method, which is used for controlling the power battery heat flow discharging device, and the power battery heat flow discharging method comprises the following steps:

setting a preset opening pressure of the drainage interface 213 according to the valve opening impact force of the pressure release valve when the battery cell 100 is out of control due to heat;

if the actual pressure of the high-temperature gas generated by the thermal runaway of the battery cell 100 is greater than the preset opening pressure, the high-temperature gas breaks through the drainage interface 213 and enters the drainage flow channel 211;

the high-temperature gas flows into the main flow passage 212 through the drainage flow passage 211;

if the pressure of the high-temperature gas flowing out of the exhaust hole 214 is greater than the preset pressure of the explosion-proof valve 13, the high-temperature gas is exhausted through the explosion-proof valve 13.

The method for discharging the heat flow of the power battery provided by the embodiment sets the preset opening pressure of the drainage interface 213 according to the valve opening impact force of the pressure release valve when the battery cell 100 is out of control due to heat, and it can be understood that the wall thickness of the drainage interface 213 is set so that the impact force of the pressure release valve of the battery cell 100 is enough to break the drainage interface 213 when the battery cell 100 is out of control due to heat, so that high-temperature gas can break the drainage interface 211 to enter the drainage flow channel 211, and is discharged from the vent hole 214 through the main flow channel 212 and then discharged by the explosion-proof valve 13, so that the diffusion of the out of control due to heat in the battery pack system is delayed under the.

In the description herein, it is to be understood that the terms "upper", "lower", "right", and the like are based on the orientations and positional relationships shown in the drawings and are used for convenience in description and simplicity in operation, but do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be constructed in a particular operation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used merely for descriptive purposes and are not intended to have any special meaning.

In the description herein, references to the description of "an embodiment," "an example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example.

In addition, the foregoing is only the preferred embodiment of the present invention and the technical principles applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.