CN219321444U - Battery pack - Google Patents

Abstract

The utility model discloses a battery pack, which comprises a battery pack, wherein the battery pack comprises a plurality of batteries which are sequentially arranged along a first direction; the cooling assembly is provided with a cavity, and phase change materials are filled in the cavity and are used for being led out from the cavity when the battery is in thermal runaway so as to reduce the temperature of the battery; and the lyophile heat insulation pad is clamped between two adjacent batteries, and can be used for absorbing the phase change material after the phase change material flows out, and the absorption multiplying power of the lyophile heat insulation pad is 0.3-30. The battery pack is provided with the lyophilic heat insulation pad between two adjacent batteries, the lyophilic heat insulation pad can absorb the phase change material that the cooling component erupts when the battery takes place thermal runaway to the phase change material takes place the phase change after receiving a large amount of heat within the lyophilic heat insulation pad, forms gaseous outflow and takes away a large amount of heat, thereby slowed down the speed that the heat spread between the battery, improved the security performance of battery pack.

Description

Battery pack

Technical Field

The utility model relates to the technical field of batteries, in particular to a battery pack.

Background

Currently, with the promotion and development of power battery systems, CIR, CTP, CTC and other technologies are applied to battery systems in succession, and the safety performance of the battery system structure and the thermal runaway of the battery are increasingly emphasized.

Thermal runaway is a serious safety accident of a battery, when a battery monomer in the battery is subjected to thermal runaway, the heat generated by the battery monomer is suddenly increased, and the heat is transferred to surrounding batteries, so that the large-scale thermal runaway of the surrounding batteries is rapidly initiated, the battery is caused to fire or even explode, and the life safety of a user is directly threatened. And along with the promotion of battery energy density, the heat that produces when battery thermal runaway can be more, can be higher to the thermal insulation performance demand of heat insulating mattress, the heat insulating mattress among the prior art is when battery thermal runaway takes place, because unable absorption moisture to in the clearance between the moisture packing insulating material, lead to the thermal insulation performance of heat insulating mattress to reduce, when the thermal runaway takes place for arbitrary battery in the battery package easily, the heat that it produced can start adjacent battery thermal runaway, causes quick thermal spread in the battery package, therefore the thermal insulation performance of heat insulating mattress has not satisfied current thermal insulation requirement.

Disclosure of Invention

In order to overcome the defects in the prior art, the utility model aims to provide a battery pack, which can absorb phase change materials of a cooling assembly by arranging a lyophilic heat insulation pad between two adjacent batteries, thereby improving the heat insulation performance of the heat insulation pad.

The utility model adopts the following technical scheme:

a battery pack, comprising:

the battery pack comprises a plurality of batteries which are sequentially arranged along a first direction;

the cooling assembly is provided with a cavity, and phase change materials are filled in the cavity and are used for being led out from the cavity when the battery is in thermal runaway so as to reduce the temperature of the battery;

and the lyophile heat insulation pad is clamped between two adjacent batteries, and can be used for absorbing the phase change material after the phase change material flows out, and the absorption multiplying power of the lyophile heat insulation pad is 0.3-30.

Compared with the prior art, the utility model has the beneficial effects that:

the battery pack of this application is equipped with lyophilic heat insulating mattress between two adjacent batteries, and this lyophilic heat insulating mattress can take place when thermal runaway at the battery, absorbs the phase change material that cooling module erupts out to phase change material takes place the phase change after receiving a large amount of heat within lyophilic heat insulating mattress, forms gaseous outflow and takes away a large amount of heat. When the phase change material is changed into gas to flow out, the lyophilic heat insulation pad recovers the heat insulation performance to continue heat insulation, so that the speed of heat spreading among batteries is slowed down, and the safety performance of the battery pack is improved.

Drawings

FIG. 1 is a cross-sectional view from a perspective of a battery pack according to an embodiment of the present disclosure;

FIG. 2 is another schematic view of a partial cell according to an embodiment of the present disclosure;

fig. 3 is a schematic diagram of an experimental design provided in an embodiment of the present disclosure.

In the figure: 1. a battery; 11. a positive electrode post; 12. a negative electrode column; 13. a first face; 14. a second face; 15. a side surface; 2. a lyophile insulation pad; 3. a cooling assembly; 31. a phase change material; 4. a battery case; 41. a beam; 42. a liquid cooling plate; 43. and a side plate.

Detailed Description

The utility model will be further described with reference to the accompanying drawings and detailed description below:

in the description of the present utility model, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, merely to facilitate description of the present utility model and simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used herein in the description of the utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model.

The utility model is described in further detail below with reference to the accompanying drawings.

In the case of example 1,

a battery pack as shown in fig. 1 and 2, comprising a battery pack including a plurality of batteries 1 arranged in sequence in a first direction, a cooling module 3, and a lyophile heat insulation pad 2; the cooling component 3 is provided with a cavity, the cavity is filled with a phase change material 31, and the phase change material 31 can be led out of the cavity when the battery 1 is in thermal runaway, so that the temperature of the battery 1 is reduced; and the lyophile heat insulation pad 2 is clamped between two adjacent batteries 1, after the batteries 1 are out of control and the phase change material 31 flows out, the lyophile heat insulation pad 2 can absorb the phase change material 31, and the absorption multiplying power of the lyophile heat insulation pad is 0.3-30.

On the basis of the above structure, during assembly, the lyophile heat insulation pad 2 is clamped between two adjacent batteries 1, and then during normal operation, the lyophile heat insulation pad 2 can effectively reduce heat transfer between the batteries 1. After the thermal runaway of the single battery 1 occurs, the cooling component 3 guides out the phase-change material 31 from the cavity, after the phase-change material 31 flows out, the cooling component contacts with the single battery 1 to reduce the temperature of the single battery 1, and then is absorbed by the lyophile heat insulation pad 2, and because the temperature generated by the battery 1 in the thermal runaway is too high, the phase-change material 31 can be gasified into gas after being absorbed into the lyophile heat insulation pad 2, thereby taking away part of heat generated by the thermal runaway of the battery 1, and after the phase-change material 31 absorbed in the lyophile heat insulation pad 2 is gasified, the lyophile heat insulation pad 2 is restored to an initial state, the heat insulation performance of the cooling component is maintained, and the heat transfer between two adjacent batteries 1 is continuously reduced.

With the continuous development of the technology of the power battery 1, the safety of the battery 1 is more and more paid attention. In the working process of the battery 1, the temperature of the internal single battery 1 can rise, if the temperature is not controlled, the thermal runaway of the single battery 1 is easily caused, and the thermal runaway is the most serious safety accident of the power battery 1. When thermal runaway occurs in the elevator battery 1 in the battery 1, heat generation amount is suddenly increased, and the heat is transferred to the surrounding batteries 1, so that the large-scale thermal runaway of the surrounding batteries 1 is rapidly initiated, the battery 1 fires and even explodes, and the life safety of a user is directly threatened.

In the prior art, in order to reduce the heat transfer efficiency between the cells 1 and to slow down the heat spreading to other peripheral cells 1 during thermal runaway, a cooling module 3 is disposed in a cell case 4, and a heat insulating pad is disposed between two adjacent cells 1. In the case of thermal runaway of the cells 1, the cooling assembly 3 ejects the phase change material 31, but in the prior art, a hydrophobic heat insulation pad is mostly adopted, and the phase change material 31 blocks the gap between the heat insulation materials, so that the heat insulation effect of the heat insulation pad is reduced, and the heat transfer between two adjacent cells 1 is relatively large, so that the thermal runaway of the peripheral cells 1 is initiated on a large scale.

In this embodiment, after the phase-change material 31 is sprayed out of the cooling component 3 by adopting the lyophile heat-insulating pad 2, the phase-change material 31 is absorbed by the lyophile heat-insulating pad 2, and the heat-insulating performance of the lyophile heat-insulating pad 2 can be ensured, and the phase-change material 31 is subjected to the heat generated by the thermal runaway of the battery 1 in the lyophile heat-insulating pad 2, so that the phase-change material 31 can be gasified into gas, and peripheral heat can be absorbed in the gasification process, thereby further improving the heat-insulating effect and the cooling effect of the lyophile heat-insulating pad 2, effectively reducing the heat transfer between two adjacent batteries 1, and effectively slowing down the heat spreading occurring during the thermal runaway, so that the time of the thermal runaway of the peripheral battery 1 in large scale can be prolonged when the thermal runaway occurs in the single battery 1, thereby delaying the time of the ignition or even explosion of the battery 1, and ensuring the life safety of the user.

It should be noted that, the phase change material 31 may be a material capable of storing more heat when the phase is changed into the gas phase in the prior art, such as water, a hydrated salt, or silicone oil, and the like, and only needs to enable the phase change material 31 to absorb and store a large amount of latent heat when the phase change material is changed into the gas phase, and may be selected and set according to the actual situation.

When the phase change material is water or hydrated salt, the lyophile heat insulation pad 2 is a hydrophilic heat insulation pad which can absorb water or hydrated salt; when the phase change material is silicone oil, the lyophile heat insulation pad 2 is a lyophile heat insulation pad, and the heat insulation pad can absorb silicone oil and exert a heat dissipation effect.

The first direction mentioned herein is the length direction of the battery pack, the batteries 1 are sequentially arranged along the length direction of the battery pack, and the lyophile heat insulation pad 2 is clamped between two adjacent batteries 1, that is, the lyophile heat insulation pads 2 are also arranged at intervals along the length direction of the battery pack. Of course, the battery pack has a length direction and a width direction, the batteries 1 can be arranged in the width direction, and the lyophile heat insulation pad 2 can be clamped between two adjacent batteries 1 in the width direction, that is, the lyophile heat insulation pads 2 can be arranged at intervals along the width direction of the battery pack.

The absorption multiplying power of the lyophile heat insulation pad 2 is 0.3-30.

In the case of test example 1,

in the present embodiment, the absorption capacity of the lyophile heat insulation pad 2 is defined as the weight capable of absorbing liquid per unit weight of the lyophile heat insulation pad, that is, absorption capacity= (post-absorption mass-pre-absorption mass)/pre-absorption mass.

The absorption rate test mode is as follows:

step one: selecting a lyophile heat insulation pad, and weighing the lyophile heat insulation pad to obtain the mass m1 of the original lyophile heat insulation material;

step two: placing the lyophile heat-insulating pad in the phase-change liquid to enable the lyophile heat-insulating material to fully absorb the phase-change liquid (for example, the lyophile heat-insulating pad is provided with a packaging layer, and the lyophile heat-insulating pad is placed in the phase-change liquid after the sealing property of the packaging layer is destroyed);

step three: weighing the lyophile heat insulation material fully absorbing the phase-change liquid, and obtaining the mass m2 of the lyophile heat insulation material after absorption;

step four: the mass of the absorbed phase-change liquid m3=m2-m 1;

step five: absorption capacity=m3/m 1.

Based on the above structure, after obtaining the absorption multiplying power of different lyophilic heat insulation pads, the heat inhibition effect of the lyophilic heat insulation pad under the condition of different absorption multiplying power is detected by the following experiment.

Test example 2 the test sample was prepared,

as shown in fig. 3, five batteries are adopted as experimental batteries, wherein the serial numbers of the experimental batteries are 1#, 2#, 3#, 4#, and 5#, a lyophile heat insulation pad is arranged between two adjacent batteries, a phase change material is arranged above the batteries, temperature monitoring sites T3 and T4 are arranged on the left side and the right side of the 3# battery to detect the temperature rise condition of the 3# battery, wherein T3 is close to one side of the 2# battery, and T4 is close to one side of the 4# battery; temperature monitoring sites T1 and T2 are arranged on the left side and the right side of the No. 2 battery to detect the temperature rise condition of the No. 2 battery, wherein T1 is close to one side of the No. 1 battery, and T2 is close to one side of the No. 3 battery; temperature monitoring sites T5 and T6 are arranged on the left side and the right side of the No. 4 battery to detect the temperature rise condition of the No. 4 battery, wherein T5 is close to one side of the No. 3 battery, and T6 is close to one side of the No. 5 battery.

The 3# battery is used as a triggering out-of-control battery, the battery can impact the cooling assembly 3 filled with the phase change material after out-of-control, the phase change material can flow down and be absorbed by the hydrophilic heat insulation pad after packaging failure, the phase change material can take away heat, and the absorption rate of the hydrophilic heat insulation pad material can influence the absorption capacity of the phase change material, so that the effect of heat inhibition under different absorption rates is influenced.

In the experiment, the temperature acquisition sheet is arranged on the temperature monitoring site to monitor the temperature, and other modes can be adopted to monitor the temperature. The temperature rise condition of the battery in 24 hours is detected to judge whether the battery is in thermal runaway, and when the temperature rise rate of the battery in 24 hours is too high, the temperature rise condition is defined as that the battery is in thermal runaway.

In the case of example 1,

taking the absorption rate of the lyophile heat-insulating pad as an example, when the lyophile heat-insulating material with the absorption rate is adopted, the maximum heating rate of T2 is 1 ℃/s, the maximum heating rate of T5 is 0.9 ℃/s, the maximum temperature of T2 is 198 ℃, the maximum temperature of T5 is 205 ℃, the absorption rate of the lyophile heat-insulating pad is increased, more phase-change materials can be absorbed, and more heat is taken away by phase change of the phase-change materials.

In the case of example 2,

taking the absorption rate of the lyophile heat-insulating pad as 1 as an example, when the lyophile heat-insulating material with the absorption rate is adopted, the maximum heating rate of T2 is 0.8 ℃/s, the maximum heating rate of T5 is 0.8 ℃/s, the maximum temperature of T2 is 192 ℃, the maximum temperature of T5 is 201 ℃, the thermal runaway of only the 3# battery is shown, and other four batteries are not caused, so that the reason is possible that the absorption rate of the lyophile heat-insulating pad is increased, more phase-change materials can be absorbed, and more heat is taken away by phase change of the phase-change materials.

In the case of example 3,

taking the absorption rate of the lyophile heat-insulating pad as 5 as an example, when the lyophile heat-insulating material with the absorption rate is adopted, the maximum temperature rise rate of T2 is 0.8 ℃/s, the maximum temperature rise rate of T5 is 0.7 ℃/s, the maximum temperature of T2 is 188 ℃, the maximum temperature of T5 is 195 ℃, the thermal runaway of only the 3# battery is shown, and the other four batteries are not thermal runaway, so that the reason is probably that the absorption rate of the lyophile heat-insulating pad is increased, more phase-change materials can be absorbed, more heat is taken away by the phase-change materials in a phase-change manner, and compared with the temperature of the embodiment 2, the temperature of T2 and the temperature of T5 are lower.

In the case of example 4,

taking the absorption rate of the lyophile heat-insulating pad as 10 as an example, when the lyophile heat-insulating material with the absorption rate is adopted, the maximum temperature rise rate of T2 is 0.7 ℃/s, the maximum temperature rise rate of T5 is 0.8 ℃/s, the maximum temperature of T2 is 180 ℃, the maximum temperature of T5 is 190 ℃, the thermal runaway of only the 3# battery is shown, and the other four batteries are not thermal runaway, so that the reason is probably that the absorption rate of the lyophile heat-insulating pad is increased, more phase-change material can be absorbed, more heat is taken away by the phase-change material in a phase change mode, and compared with the temperature of the embodiment 2 or 3, and the temperature of T2 and T5 is lower.

In example 5 the process was carried out,

taking the absorption rate of the lyophile heat-insulating pad as 30 as an example, when the lyophile heat-insulating material with the absorption rate is adopted, the maximum temperature rise rate of T2 is 0.7 ℃/s, the maximum temperature rise rate of T5 is 0.8 ℃/s, the maximum temperature of T2 is 176 ℃, the maximum temperature of T5 is 184 ℃, the thermal runaway of only the 3# battery is shown, and the other four batteries are not thermal runaway, so that the reason is probably that the absorption rate of the lyophile heat-insulating pad is increased, more phase-change material can be absorbed, more heat is taken away by the phase-change material in a phase change manner, and compared with the temperature of examples 2, 3 or 4, and the temperatures of T2 and T5 are lower.

In comparative example 1,

taking the absorption rate of the lyophile heat-insulating pad as 0.1 as an example, when the lyophile heat-insulating material with the absorption rate is adopted, the maximum heating rate of T2 is 335 ℃/s, the maximum heating rate of T5 is 330 ℃/s, and the 2# and 4# batteries are in thermal runaway, so that the thermal inhibition effect is not realized, and the reason may be that the absorption rate of the lyophile heat-insulating pad is small, the phase-change material is not absorbed by the lyophile heat-insulating pad after flowing out, and flows to the bottom of the battery box body, so that the thermal inhibition effect is poor.

Comparative example 2,

taking 35 as an example of the absorption rate of the lyophile heat-insulating pad, when the lyophile heat-insulating material with the absorption rate is adopted, the maximum heating rate of T2 is 341 ℃/s, the maximum heating rate of T5 is 337 ℃/s, and the 2# and 4# batteries are out of control, so that the heat inhibition effect is not realized, and the reason may be that the absorption rate of the lyophile heat-insulating pad is too large, only the upper part of the lyophile heat-insulating pad is fully absorbed by the lyophile heat-insulating pad after the phase change material flows out, the lower part of the lyophile heat-insulating pad is free of the phase change material, the lower part of the lyophile heat-insulating pad is heat-transferred, and the heat inhibition effect is poor; meanwhile, as the absorption multiplying power of the lyophile heat insulation pad is too large, the phase change material is excessively absorbed by the lyophile heat insulation pads on the two sides of the 3# battery, and the other heat insulation pads do not absorb the phase change material and do not play a phase change role.

Examples 1-5 and comparative examples 1-2 were prepared as set forth in Table one below:

list one

As can be seen from the above table one, in the case that the absorption magnification of the lyophile heat insulation pad 2 is 0.3, 1, 5, 10, 30, the lyophile heat insulation pad 2 can effectively absorb the phase change material and make the phase change material phase change to take away a large amount of heat, thereby effectively realizing heat inhibition. When the absorption capacity of the lyophile heat-insulating pad is 0.1 or 35, thermal runaway occurs in the 2# and 4# batteries, and thermal inhibition cannot be effectively achieved.

From the above, it can be seen that when the absorption ratio of the lyophile heat insulation pad 2 is in the range of 0.3-30, the higher the absorption ratio of the lyophile heat insulation pad, the better the heat dissipation effect and the heat suppression effect; when the absorption capacity of the lyophile heat insulation pad 2 is out of the range of 0.3-30, the phase change material cannot effectively achieve heat inhibition.

Further, the lyophile heat insulation pad 2 comprises an encapsulation layer and a lyophile heat insulation material, the encapsulation layer is coated outside the lyophile heat insulation material, and the encapsulation layer is used for melting when the battery 1 is in thermal runaway so that the lyophile heat insulation material absorbs the phase change material 31.

On the basis of the structure, the packaging layer is used for coating the lyophile heat insulation material, so that the lyophile heat insulation material is effectively prevented from absorbing moisture in the air in the normal working process of the battery 1, and the heat insulation performance of the lyophile heat insulation pad 2 is affected. And when thermal runaway occurs in the battery 1, the encapsulation layer is melted at a high temperature and the lyophile heat insulating material is exposed to air, so that the lyophile heat insulating material can absorb the phase change material 31.

It should be noted that, the above-mentioned packaging layer may be made of a plastic with a lower melting point in the prior art, so that the lyophile heat insulation material is sealed inside the packaging layer, and when the battery 1 is thermally out of control, the packaging layer may be melted and the lyophile heat insulation material is exposed, or the packaging layer may be made of a material such as polyethylene, resin, etc., and may be selected and set according to the needs of the actual situation.

In addition, the absorption rate of the lyophile heat insulation pad 2 can be adjusted by selecting different lyophile heat insulation materials, for example, lyophile fiber aerogel, ceramic fiber, glass fiber, pre-oxidized fiber and the like can be adopted as lyophile heat insulation materials, the materials can effectively play a role in heat insulation, heat transfer to the adjacent battery 1 is blocked, and when the battery 1 is out of control, the materials can play the lyophile property, and effectively absorb the phase change material 31 flowing out of the cooling component 3, so that the phase change material 31 is changed into a gas phase in the heat insulation pad, and absorbs and stores heat, thereby cooling the battery 1, slowing down the speed of heat spreading, and being selected and set according to the needs of actual situations.

Or the absorption capacity of the lyophile heat insulation pad 2 is adjusted by using the same kind of lyophile heat insulation material but lyophile heat insulation materials with capillary diameters different from structures. The absorption capacity of the lyophile heat insulation pad 2 is adjusted by compressing the lyophile heat insulation material to adjust the pore diameter and the structure of the lyophile heat insulation material.

The absorption multiplying power of the lyophile heat insulation pad 2 can also be adjusted by selecting a heat insulation pad with double layers, three layers or multiple layers of overlapped materials, such as at least one layer of heat insulation material and one layer of lyophile material, and adjusting the thickness and the volume of the lyophile material, and the preferred structure is a sandwich structure with one layer of heat insulation material sandwiched between two layers of lyophile material.

Further, the melting point of the encapsulation layer needs to be less than or equal to 400 ℃.

Based on the above structure, the battery 1 is manufactured at a temperature of about 400 c when thermal runaway occurs, and the encapsulation layer should be made of a material having a melting point in the range of 400 c or less in order to allow the encapsulation layer to be smoothly melted and the lyophile heat insulating material sealed therein to be exposed when thermal runaway occurs.

Further, the absorption rate of the lyophile heat insulation pad 2 is 1-10.

On the basis of the above-mentioned structure, as is clear from table 1, example 3, example 4 and example 5, taking the absorption rate of the lyophile heat-insulating pad 2 as an example, when the lyophile heat-insulating material with the absorption rate is adopted, only the 3# battery is out of control, and the other four batteries are not out of control, the absorption rate of the lyophile heat-insulating pad 2 is increased, more phase-change material can be absorbed, and more heat is taken away by the phase-change material, but the effect of the lyophile heat-insulating pad 2 with the absorption rate is better than that of the lyophile heat-insulating pad 2 with the absorption rate of 0.3.

Taking the absorption rate of the lyophile heat-insulating pad 2 as 10 as an example, when the lyophile heat-insulating material with the absorption rate is adopted, only the 3# battery is in thermal runaway, and other four batteries are not in thermal runaway, so that the reason is possible, the absorption rate of the lyophile heat-insulating pad 2 is increased, more phase-change material can be absorbed, more heat is taken away by phase-change material phase change, and the temperature of two adjacent batteries is lower than that of the embodiment 3 or 4,3# batteries.

As can be seen from the above, when the absorption rate of the lyophile heat insulation pad 2 is in the range of 0.3-30, the absorption rate is in direct proportion to the volume of the lyophile heat insulation pad 2, and when the volume of the lyophile heat insulation pad 2 is increased, the absorption rate is also increased, but the space occupied by the lyophile heat insulation pad 2 inside the battery case 4 is also increased, thereby reducing the discharging efficiency and performance of the battery pack. Therefore, the absorption capacity of the lyophile heat insulation pad 2 should be set in the range of 0.3-30, and further preferably the absorption capacity is in the range of 1-10.

Further, the interval between adjacent two cells 1 is 0.5mm to 10mm.

On the basis of the above structure, the interval between two adjacent cells 1 should be 0.5mm-10mm, so that the lyophile heat insulation pad 2 can have sufficient space to be clamped between the two adjacent cells 1.

Taking an example that the interval between two adjacent cells 1 is 0.5mm, when the interval between two adjacent cells 1 is 0.5mm, the thickness of the lyophile heat insulation pad 2 clamped between the two cells 1 at this time can only be less than or equal to 0.5mm. As can be seen from the above, the thickness and volume of the lyophile heat-insulating mat 2 affect the absorption rate of the lyophile heat-insulating mat 2 for absorbing the phase-change material 31, and when the thickness of the lyophile heat-insulating mat 2 is less than or equal to 0.5mm, the absorption rate is low, and more phase-change material 31 cannot be absorbed, and when the phase-change material 31 changes into gas phase in the lyophile heat-insulating mat 2, less heat can be absorbed and stored, so that the cooling effect of the lyophile heat-insulating mat 2 is poor.

Taking an example that the interval between two adjacent cells 1 is 10mm, when the interval between two adjacent cells 1 is 10mm, the thickness of the lyophile heat insulation pad 2 clamped between the two cells 1 at this time can be only 10mm or less. As can be seen from the above, the thickness and the volume of the lyophile heat insulation pad 2 affect the absorption rate of the lyophile heat insulation pad 2 for absorbing the phase change material 31, and when the thickness of the lyophile heat insulation pad 2 is less than or equal to 10mm, the absorption rate of the lyophile heat insulation pad is higher, and the lyophile heat insulation pad can absorb relatively more phase change material 31, but the lyophile heat insulation pad 2 occupies more space inside the battery case 4, so that the space utilization inside the battery case 4 is reduced, and thus the energy density of the battery 1 is reduced, and more batteries 1 cannot be installed, thereby reducing the discharge efficiency and performance of the battery 1.

Further, the interval between adjacent two cells 1 is 0.5mm to 5mm.

On the basis of the above structure, taking an example that the interval between two adjacent cells 1 is 5mm, when the interval between two adjacent cells 1 is 5mm, the thickness of the lyophile heat insulation pad 2 clamped between the two cells 1 at this time can only be less than or equal to 5mm. As can be seen from the above, the thickness and the volume of the lyophile heat-insulating pad 2 affect the absorption rate of the lyophile heat-insulating pad 2 for absorbing the phase-change material 31, and when the thickness of the lyophile heat-insulating pad 2 is less than or equal to 5mm, the absorption rate of the lyophile heat-insulating pad is higher, so that relatively more phase-change material 31 can be absorbed, and when the thickness of the lyophile heat-insulating pad 2 is less than the thickness of the heat-insulating pad when the interval between two adjacent batteries 1 is 10mm, the lyophile heat-insulating pad 2 can not occupy too much space of the battery box 4, and the discharging efficiency and performance of the batteries 1 are ensured.

As is clear from the above, when the interval between two adjacent batteries 1 is 0.5mm to 10mm, the thickness of the lyophile heat insulation pad 2 increases as the interval between two batteries 1 increases, and the increase in the thickness of the lyophile heat insulation pad 2 also causes an increase in the absorption rate, but at the same time the space of the battery case 4 occupied increases, thereby resulting in a decrease in the energy density of the batteries 1, failing to mount more batteries 1, and further decreasing the discharge efficiency of the batteries 1. Therefore, the interval between two adjacent batteries 1 should be set within the range of 0.5mm-10mm, so that not only can the absorption rate of the lyophile heat insulation pad 2 be ensured, but also the phase change material 31 can be absorbed, the heat dissipation function and the heat insulation function can be fully exerted, more space of the battery box 4 can not be occupied, and the discharge efficiency and the performance of the batteries 1 are ensured.

Example 6, on the basis of all the above examples,

further, the cooling module 3 is provided with a lead-out portion for guiding the phase change material 31 to be led out of the cavity when the battery 1 is thermally out of control.

On the basis of the above-described structure, in the present embodiment, specifically, during normal operation of the battery 1, the phase change material 31 is stored in the cavity of the cooling module 3, and once thermal runaway occurs in the battery 1, the lead-out portion in the cooling module 3 forms an opening, so that the phase change material 31 in the cavity flows out from the lead-out portion and cools the runaway battery 1.

It should be noted that this guiding-out portion may be a weak portion, or may be a guiding-out hole and a plugging member described below, or may be provided in other manners, such as a spraying pipeline, etc., only by spraying the phase-change material 31 when the cooling component 3 is out of control when the battery 1 is thermally in a state, so as to cool down the battery 1, and may be selected and set according to the needs of practical situations.

Example 7 based on the above example 6,

further, the lead-out portion includes a lead-out hole penetrating the cavity, and a blocking member blocking the lead-out hole, the blocking member being for melting after thermal runaway of the battery 1 to lead out the phase change material 31 from the lead-out hole.

On the basis of the above structure, when thermal runaway occurs in the battery 1, the blocking member starts to melt by the high temperature generated by the thermal runaway battery 1, so that the lead-out hole is opened, the phase change material 31 in the cavity can be led out from the lead-out hole, and the thermal runaway battery 1 is cooled.

It should be noted that, the plugging member should be made of a material with a low melting point, so that the plugging member can be melted due to a high temperature generated by thermal runaway of the battery 1 under the condition of thermal runaway of the battery 1, and plastics or colloid with a low melting point in the prior art can be selected and set according to the needs of practical situations.

In this way, it is possible to effectively cause the cooling module 3 to release the phase change material 31 instantaneously when the battery 1 is thermally out of control, thereby cooling the thermally out of control battery 1.

Example 8, on the basis of example 6 or example 7 above,

further, a pressure pump is provided in the cooling module 3, and the pressure pump is used for generating pressure to press the lead-out part when the battery 1 is out of control thermally, and the lead-out part is used for guiding the phase change material 31 to lead out when the deformation is generated during pressing.

On the basis of the above structure, when thermal runaway occurs in the battery 1, the pressure pump in the cooling module 3 applies pressure to the lead-out portion of the cooling module 3, so that the lead-out portion deforms to form an opening, or the plugging member of the cooling module 3 is applied pressure, so that the lead-out hole is opened, then the phase change material 31 in the cavity can be led out, and the thermal runaway battery 1 is cooled.

In this way, the phase change material 31 can be released immediately when the battery 1 is in thermal runaway by the cooling assembly 3, so that the battery 1 in thermal runaway can be cooled. And if the lead-out part is a weak part of the cooling assembly 3, the manufacturing cost and the manufacturing procedure can be reduced; in addition, the time for releasing the phase-change material 31 can be shortened by using the pressure pump without waiting for the melting of the blocking piece, so that the phase-change material 31 can instantly cool the battery 1.

Further, the battery pack also comprises a temperature sensor, and the temperature sensor is electrically connected with the pressure pump; the temperature sensor is used for detecting the temperature change of the battery 1 and sending a temperature signal; the pressure pump can be activated in response to a temperature signal.

On the basis of the above structure, specifically, the temperature collecting point of the temperature sensor is arranged on the top cover of the battery 1 or the pole of the battery 1, once the temperature sensor detects that the temperature change of the battery 1 exceeds a set value, the battery 1 starts to generate a thermal runaway phenomenon, the temperature sensor sends a temperature signal to the pressure pump, the pressure pump can start up after receiving the temperature signal, and the leading-out part is pressed, so that the leading-out part is deformed and forms an opening, the phase change material 31 flows out of the cavity, and the battery 1 is cooled in time.

The provision of the temperature sensor further ensures that the cooling module 3 is able to accurately conduct out the phase change material 31 inside the cavity when thermal runaway of the battery 1 occurs, thereby cooling the battery 1. The more the cooling assembly 3 can instantly cool the battery 1 which is out of control, the more the speed of heat spreading can be prolonged, thereby further prolonging the escape time of the user and ensuring the safety of the user.

Example 9, on the basis of all the above examples,

further, the battery 1 is provided with a first surface 13, the first surface 13 is provided with an explosion-proof valve, the cooling module 3 is provided on the first surface 13, and the projection of the lead-out part on the first surface 13 is at least partially overlapped with the explosion-proof valve.

In addition to the above-described structure, when the battery 1 is thermally out of control, the explosion-proof valve on the battery 1 is exploded, and at this time, since the lead-out portion is at least partially overlapped with the explosion-proof valve, the lead-out portion is also broken after the explosion-proof valve is exploded, so that the lead-out portion is deformed to form an opening.

Through the combined action of the explosion-proof valve and the pressure pump, the time for forming the opening by deformation of the leading-out part becomes shorter, so that the phase change material 31 can be led out from the cavity in a shorter time, the battery 1 is cooled, and the heat spreading speed of the battery 1 and the escape time of a user are further prolonged.

The battery 1 includes a top surface provided with a pole and an explosion-proof valve, a bottom surface opposite to the top surface, and a side surface of the battery 1. In this embodiment, the first surface is the top surface of the battery 1, and the second surface is the bottom surface of the battery 1.

Further, the battery 1 is provided with a side surface 15 and a second surface 14, the side surface 15 is connected to the first surface 13, the second surface 14 is opposite to the first surface 13, and the cooling module 3 is provided on the side surface 15 and the second surface 14, or is provided on the side surface 15.

On the basis of the structure, the cooling assemblies 3 can be arranged on different surfaces of the battery 1, so that when the battery 1 is in thermal runaway, the cooling assemblies 3 on the different surfaces can lead out the phase change material 31 to cool each surface of the battery 1, the cooling efficiency of the phase change material 31 on the battery 1 is enhanced, and the thermal runaway speed of the battery 1 is effectively reduced.

Further, the cooling unit 3 may be a beam 41, a side plate 43 attached to the battery side 15, a bottom liquid cooling plate 42, a top liquid cooling plate 42, or a top shower pipe.

In this embodiment, specifically, when the cooling module 3 is disposed at the side of the battery pack, the cooling module 3 may be a beam 41, a side plate 43 attached to the side surface 15 of the battery pack, and a liquid cooling plate 42, that is, the beam 41 on the battery case 4, the side plate 43 attached to the side surface 15 of the battery pack, and the liquid cooling plate 42 are provided with cavities, and the phase change material 31 is filled in the cavities. Once thermal runaway of the battery 1 occurs, these cooling modules 3 lead out of the phase change material 31 at the sides 15 of the battery 1, thereby cooling the battery 1.

When the cooling assembly 3 is disposed on the second surface 14 of the battery pack, that is, the bottom surface of the battery, the cooling assembly 3 may be a liquid cooling plate 42, the liquid cooling plate 42 is abutted against the second surface 14 of the battery pack, when the battery 1 works normally, the liquid cooling plate 42 may cool the battery 1, and after the battery 1 is thermally out of control, the liquid cooling plate 42 flows out of the phase change material 31 from the second surface 14 of the battery 1, so as to cool the battery 1.

When cooling module 3 sets up in the first face 13 of group battery, namely when the top surface of battery, cooling module 3 also can be liquid cooling board 42, and liquid cooling board 42 and the first face 13 butt of group battery, and when battery 1 normally works, liquid cooling board 42 also can cool down to battery 1, and after battery 1 takes place thermal runaway, liquid cooling board 42 will flow out phase change material 31 to cool down to battery 1.

Further, the cooling module 3 disposed on the first surface 13 of the battery 1 may also be configured as a top spraying pipeline structure, and after the battery 1 is thermally out of control, the top spraying pipeline sprays the phase change material 31 to the battery 1, so as to cool the battery 1.

Of course, the cooling module 3 may be implemented by various other embodiments besides the above embodiments, for example, the cooling module is only disposed on a side beam or attached to a side of the battery pack, or may be implemented by combining the top liquid cooling plate 42 with the bottom liquid cooling plate 42, or combining the top spraying pipeline with the bottom liquid cooling plate 42, or the like, and may be implemented by using a single cooling module 3 or combining multiple cooling modules 3, or may be implemented by using other cooling modules 3 in the prior art, which may be selected and set according to actual needs.

It will be apparent to those skilled in the art from this disclosure that various other changes and modifications can be made which are within the scope of the utility model as defined in the appended claims.

Claims (12)

1. A battery pack, comprising:

a battery pack including a plurality of cells (1) arranged in sequence in a first direction;

-a cooling assembly (3), the cooling assembly (3) being provided with a cavity, the cavity being filled with a phase change material (31), the phase change material (31) being for being guided out of the cavity to lower the temperature of the battery (1) when the battery (1) is thermally out of control;

a lyophile heat insulation pad (2), wherein the lyophile heat insulation pad (2) is clamped between two adjacent batteries (1), and the lyophile heat insulation pad (2) can be used for absorbing the phase change material (31) after the phase change material (31) flows out; the absorption multiplying power of the lyophile heat insulation pad (2) is 0.3-30.

2. The battery pack according to claim 1, wherein the lyophile heat insulation pad (2) comprises an encapsulation layer and a lyophile heat insulation material, the encapsulation layer being coated outside the lyophile heat insulation material, the encapsulation layer being configured to melt upon thermal runaway of the battery (1) so that the lyophile heat insulation material absorbs the phase change material (31).

3. The battery pack of claim 2, wherein the encapsulant layer has a melting point of 400 ℃ or less.

4. The battery pack according to claim 1, wherein the lyophile heat insulation pad (2) has an absorption rate of 1 to 10.

5. Battery pack according to claim 1, characterized in that the spacing between adjacent two of the batteries (1) is 0.5-10 mm.

6. The battery pack according to claim 5, wherein the interval between adjacent two of the batteries (1) is 0.5mm to 5mm.

7. Battery pack according to any of claims 1-6, characterized in that the cooling module (3) is provided with a lead-out for guiding the phase change material (31) out of the cavity in case of thermal runaway of the battery (1).

8. The battery pack according to claim 7, wherein the lead-out portion includes a lead-out hole penetrating the cavity, and a blocking member blocking the lead-out hole, the blocking member being for melting after thermal runaway of the battery (1) to lead out the phase change material (31) from the lead-out hole.

9. Battery pack according to claim 7, characterized in that a pressure pump is provided in the cooling module (3) for generating pressure to press the lead-out portion for guiding the phase change material (31) out when pressed, in case of thermal runaway of the battery (1).

10. The battery pack of claim 9, further comprising a temperature sensor electrically connected to the pressure pump; the temperature sensor is used for detecting the temperature change of the battery (1) and sending a temperature signal; the pressure pump is used for starting according to the temperature signal.

11. The battery pack according to claim 7, wherein the battery (1) is provided with a first face (13), the first face (13) is provided with an explosion-proof valve, the cooling assembly (3) is provided on the first face (13), and the projection of the lead-out part on the first face (13) is at least partially overlapped with the explosion-proof valve.

12. Battery pack according to claim 11, wherein the battery (1) is provided with a side surface (15) and a second surface (14), the side surface (15) being connected to the first surface (13), the second surface (14) being opposite to the first surface (13), the cooling assembly (3) being provided at the side surface (15) and/or the second surface (14).

Images