CN217114532U

CN217114532U - High-capacity battery shell structure

Info

Publication number: CN217114532U
Application number: CN202122541361.5U
Authority: CN
Inventors: 张三学; 雷政军; 翟腾飞; 雷玮; 蔡潇
Original assignee: Shaanxi Yadianna Power Energy Co ltd
Current assignee: Shaanxi Yadianna Power Energy Co ltd
Priority date: 2021-10-21
Filing date: 2021-10-21
Publication date: 2022-08-02
Anticipated expiration: 2031-10-21

Abstract

The utility model provides a large capacity battery shell structure belongs to energy storage battery technical field, and it includes the cavity structure, and the cavity structure intussuseption is filled with the paraffin layer, and the paraffin layer is used for absorbing the latent heat that the battery during operation produced. The paraffin has good latent heat and can absorb heat generated by the large-capacity battery during working, so that the large-capacity battery is cooled, the working temperature of the large-capacity battery is kept below 50 ℃, the working stability of the large-capacity battery is ensured, and the large-capacity battery works efficiently; the life of the large-capacity battery is prolonged.

Description

High-capacity battery shell structure

Technical Field

The utility model belongs to the technical field of the energy storage battery, a large capacity lithium cell safety technique is related to, specifically is a large capacity battery case structure.

Background

In recent years, lithium ion battery technology has been rapidly developed and has been applied to more and more fields. However, due to the working principle and the structural characteristics of the lithium ion battery, when the lithium ion battery has overcharge, short circuit, overheating or manufacturing defects, internal short circuits of a positive electrode and a negative electrode can be caused, a large amount of combustible gas and heat can be instantly generated in a battery cell, the battery can be subjected to thermal runaway combustion caused by the reaction of components such as a diaphragm, electrolyte and the like at high temperature in the battery, a large amount of combustible gas can be generated in a battery cell material during thermal runaway, a battery box is torn or exploded, and thermal runaway diffusion and aggravation can be caused by the contact and combustion of a large amount of oxygen and the combustible gas, so that a large-area fire is difficult to suppress, and the hazard is very large.

According to the existing research, the normal operation temperature of the lithium ion battery is concentrated at 0-40 ℃; when the temperature exceeds 50 ℃, the SEI film on the surface of the positive electrode cannot be kept stable, and the service life and safety of the battery are influenced; the low-temperature working condition can cause the internal chemical reaction of the battery to be slowed down, and the conductivity of the electrolyte and the diffusion rate of lithium ions of the positive electrode are reduced, so that the capacity of the battery is reduced, and even the overall failure of the battery is caused. In addition, the strong polarization effect of low temperature on the graphite anode can also cause the occurrence of lithium plating on the surface of the electrode, and the aging of the battery is accelerated. In addition to the requirement for the overall temperature range of the battery, the temperature difference has a great influence on the performance and safety of the battery, because the existence of the temperature difference can cause imbalance of chemical reactions inside the battery, thereby affecting the safe and effective operation of the battery.

In the current market, for the heat management of the lithium ion battery, an air conditioning system or circulating liquid is mainly used for cooling or heating the battery, and the heat management mode has high energy consumption and poor refrigerating or heating effect.

The patent publication CN 106654430B discloses a thermal management system for a power battery at low temperature based on a heat pipe and a phase-change material, which comprises a battery, a phase-change material and a heat pipe; the batteries are placed in a separate battery box; the phase change material is placed in a separate phase change material box; each battery in the battery box is attached to one end of at least one heat pipe; the other end of the heat pipe extends into the phase-change material box to be contacted with the phase-change material; it also includes an insulating layer which wraps the whole system. The system utilizes the heat pipe to transfer heat generated when the power battery operates, utilizes the phase-change material to store the heat, and conveys the heat when the temperature of the battery is reduced, so that the purpose of heat preservation of the battery is achieved. In the system, when the latent heat of phase change of the phase change material is exhausted, the heat absorption and release capacity is obviously reduced, and the heat dissipation or heating requirement of the battery cannot be met.

SUMMERY OF THE UTILITY MODEL

To above-mentioned current battery thermal management system, its not good problem of regulating effect to battery thermal runaway temperature (heating or refrigeration), the utility model provides a large capacity battery shell structure.

The utility model is characterized in that a paraffin layer is arranged in a cavity structure formed between the outer shell and the inner shell, and the paraffin has good phase change latent heat, so that the heat generated when the battery works normally can be absorbed, and the purpose of cooling the battery is achieved; meanwhile, the heat pipe is arranged in the paraffin layer, and when the paraffin layer is completely melted, the heat pipe can lead the heat of the paraffin out of the outer side of the battery shell to dissipate the heat; if the battery is in a low-temperature environment, in order to provide a good working temperature environment for the battery, the heat pipe can heat the battery through external heating equipment, so that the battery keeps good working efficiency; the specific technical scheme is as follows:

the utility model provides a large capacity battery shell structure, includes the cavity structure, cavity structure intussuseption is filled with the paraffin layer, the paraffin layer is used for absorbing the heat that the battery during operation produced.

Further inject, the high-capacity battery shell structure still includes interior casing and the shell body that sets gradually from inside to outside, the cavity structure sets up between shell body and interior casing, the inner chamber of interior casing is used for placing the electric core of high-capacity battery.

Further defined, the paraffin layer comprises paraffin and a heat conducting material, and the paraffin and the heat conducting material are uniformly mixed; the heat conduction material is foam copper, foam aluminum, graphite, copper powder, aluminum powder or carbon fiber.

Further defined, a heat pipe is inserted into the paraffin layer.

Further, the heat pipes are provided with a plurality of heat pipes, and the plurality of heat pipes are arranged in parallel.

Further, the heat pipe is attached to the outer side of the wall of the inner shell.

Further limited, the heat conducting medium of the heat pipe is one or a combination of two or more of acetone, water, alcohol, ammonia water, pentane and Freon 11.

Further inject, large capacity battery shell structure still includes the upper cover plate, the top opening part of shell body and interior casing is arranged in to the upper cover plate, the heat pipe runs through the upper cover plate and extends the upper cover plate top and be connected with refrigeration heating module.

Further limiting, a flame retardant is added into the paraffin wax; one or more weakenings are arranged on the wall of the inner shell.

Further, the flame retardant is a brominated flame retardant or a phosphorus-nitrogen flame retardant.

Further defined, the weakened portion is a fusible metal sheet, a scored groove, or a weakened hole.

Further defined, the outer and inner housings are each of cylindrical or prismatic configuration.

Further defined, the paraffin wax has a melting point greater than 45 ℃.

Compared with the prior art, the beneficial effects of the utility model reside in that:

1. the utility model relates to a large capacity battery shell structure, it includes the cavity structure, is filled with the paraffin layer in the cavity structure intussuseption, and the paraffin layer is used for absorbing the heat that the battery during operation produced. The melting point of the paraffin is more than 45 ℃, so when the heat generated by the battery during working is more than 45 ℃, the paraffin has good latent heat and can absorb the heat generated by the high-capacity battery during working, thereby cooling the high-capacity battery, keeping the working temperature of the high-capacity battery below 50 ℃, ensuring the high-capacity battery to work stably and ensuring the high-efficiency working of the high-capacity battery; the life of the large-capacity battery is prolonged.

2. The paraffin layer comprises paraffin and a heat conduction material, and the paraffin and the heat conduction material are uniformly mixed; make heat conduction rate accelerate through the heat conduction material, improved the radiating rate in the battery, ensure simultaneously that the heat transfer at each inside position of battery is even, avoid the inside local overheat of battery.

3. A heat pipe is inserted in the paraffin layer. The heat absorbed by the paraffin can be conducted and dissipated through the heat pipe, and when the temperature of the battery is too high, the paraffin layer and the heat pipe cooperate to enable the heat dissipation effect to be better.

4. The top openings of the outer shell and the inner shell are provided with upper cover plates, and the tops of the outer shell and the inner shell can be sealed through the upper cover plates; the heat pipe penetrates through the upper cover plate and extends above the upper cover plate to be connected with the refrigerating and heating module, and the refrigerating and heating module can help the heat pipe to better radiate heat when radiating outwards; meanwhile, when the battery operates in a low-temperature environment, the refrigeration and heating module can heat the heat pipe, and based on the bidirectional heat conduction characteristic of the heat pipe, heat is conducted to the interior of the battery through the heat pipe to heat the interior of the battery, so that the battery is in a normal working environment temperature, and the working efficiency of the battery is improved.

5. The flame retardant is added into paraffin, one or more weak parts are arranged on the shell wall of the inner shell, when the battery generates combustible gas due to thermal runaway, the pressure in the inner cavity of the inner shell is continuously increased, when the pressure reaches the limit, the weak part of the cavity wall of the inner shell is opened, the melted paraffin carries the flame retardant to enter the inner cavity of the inner shell, and the flame retardant is large in resistance and contains flame retardant materials, so that the conductive capacity of a large-capacity battery cell can be reduced, and the thermal runaway is prevented from further spreading.

Drawings

Fig. 1 is a schematic structural diagram of a high-capacity battery case structure according to the present invention;

FIG. 2 is a schematic view of the connection between the inner and outer housings;

the battery comprises a shell 1, an upper cover plate 2, a heat pipe 3, a battery anode 4, a battery cathode 5, an inner shell 6 and a weak part 7.

Detailed Description

The technical solution of the present invention is further explained below with reference to the drawings and examples, but the present invention is not limited to the embodiments explained below.

The utility model relates to a large capacity battery case structure, including the cavity structure, the cavity structure intussuseption is filled with the paraffin layer, and the paraffin layer is used for absorbing the heat that the battery during operation produced. The high-capacity battery shell structure further comprises an inner shell 6 and an outer shell 1 which are sequentially arranged from inside to outside, the cavity structure is arranged between the outer shell 1 and the inner shell 6, and the inner cavity of the inner shell 6 is used for placing the battery core of the high-capacity battery. The paraffin layer comprises paraffin and a heat conduction material, and the paraffin and the heat conduction material are uniformly mixed; the heat conducting material is foam copper, foam aluminum, graphite, copper powder, aluminum powder or carbon fiber. The heat pipes 3 are provided with a plurality of heat pipes 3 which are arranged in parallel. The heat pipe 3 is attached to the outer side of the wall of the inner shell 6. The heat conducting medium of the heat pipe 3 is one or the combination of two or more of acetone, water, alcohol, ammonia water, pentane and freon 11. The high-capacity battery shell structure further comprises an upper cover plate 2, the upper cover plate 2 is arranged at the top openings of the outer shell 1 and the inner shell 6, and the heat pipe 3 penetrates through the upper cover plate 2 and extends to be connected with the refrigerating and heating module above the upper cover plate 2. A flame retardant is added into the paraffin; the wall of the inner housing 6 is provided with one or more weakenings 7. The flame retardant is a brominated flame retardant or a phosphorus-nitrogen flame retardant. The heat pipe 3 is inserted in the paraffin layer. The weakened portion 7 is a fusible metal piece, a scored groove or a weakened hole. The outer housing 1 and the inner housing 6 are both of cylindrical or prismatic configuration. The melting point of the paraffin wax is more than 45 ℃.

Example 1

Referring to fig. 1 and 2, the high-capacity battery casing structure of the present embodiment includes an inner casing 6, an outer casing 1, and a cavity structure, where the inner casing 6 and the outer casing 1 are in turn from inside to outside, and the cavity structure is formed between the inner casing 6 and the outer casing 1, and since paraffin has good latent heat, a paraffin layer is used to absorb heat generated during battery operation; the inner cavity of the inner shell 6 is used for placing the electric core of the high-capacity battery.

Preferably, the inner shell 6 and the outer shell 1 of the present embodiment are both of a quadrangular device structure, and a cavity structure is arranged between four side surfaces of the inner shell 6 and the outer shell 1; namely, the cross section of the cavity structure is a rectangular ring structure.

Preferably, the paraffin layer of this embodiment includes paraffin and heat conduction material, paraffin and heat conduction material homogeneous mixing, the heat conduction material is on the copper foam, carries out load and bearing to paraffin through the copper foam.

Preferably, the mass ratio of the paraffin to the heat conduction material is as follows: 10:1-5:1.

Preferably, the paraffin wax has a melting point of greater than 45 ℃.

In the embodiment, the heat pipes are inserted in the paraffin layer, 5 heat pipes 3 are correspondingly arranged on one side surfaces of the inner shell 6 and the outer shell 1, namely, 20 heat pipes 3 are arranged on the four side surfaces, and the 20 heat pipes 3 are uniformly distributed in the paraffin layer.

It should be noted that the number of the heat pipes 3 in the paraffin layer may be 5, 10, 15, 25, or even more, and the specific number may be set according to the heat dissipation or heating requirement in the battery.

Preferably, the heat pipe 3 of the present embodiment is tightly attached to the outer side of the wall of the inner housing 6.

Preferably, the heat conducting working medium filled in the heat pipe 3 of the present embodiment is acetone.

Preferably, the high-capacity battery casing structure of the embodiment further includes an upper cover plate 2, the upper cover plate 2 is provided with a battery anode 4 and a battery cathode 5, and the battery anode 4 and the battery cathode 5 are electrically connected with an anode pole and a cathode pole corresponding to a battery core of the high-capacity battery; the upper cover plate 2 is arranged at the top openings of the inner shell 1 and the outer shell 6, and the heat pipe 3 penetrates through the upper cover plate 2 and extends above the upper cover plate 2 to be connected with the refrigerating and heating module.

Preferably, the refrigerating and heating module of the present embodiment is a semiconductor refrigerating and heating module.

Example 2

The embodiment provides a large capacity battery shell structure, and it includes interior casing 6, shell body 1 and cavity structure, and interior casing 6 and shell body 1 are by the inside and outside in proper order, form the cavity structure between interior casing 6 and shell body 1, because paraffin has good latent heat, the paraffin layer is used for absorbing the heat that the battery during operation produced.

Preferably, the inner shell 6 and the outer shell 1 of the present embodiment are both cylindrical structures, and a cavity structure is arranged between the side surfaces of the inner shell 6 and the outer shell 1; namely, the cross section of the cavity structure is of a circular ring structure; the inner cavity of the inner shell 6 is used for placing the electric core of the high-capacity battery.

Preferably, the paraffin layer of this embodiment includes paraffin and heat conduction material, paraffin and heat conduction material homogeneous mixing, and the heat conduction material is on the foamed aluminum, carries out load and bearing to paraffin through the foamed aluminum.

Preferably, the paraffin wax has a melting point of greater than 45 ℃.

In this embodiment, heat pipes are inserted into the paraffin layer, 20 heat pipes 3 are correspondingly disposed between the inner shell 6 and the outer shell 1, and the 20 heat pipes 3 are uniformly distributed in the paraffin layer.

Preferably, the heat conducting working medium filled in the heat pipe 3 of the present embodiment is water.

Preferably, the refrigeration and heating module of the embodiment is a structure formed by a heat dissipation fan and a heating wire, wherein the heat dissipation fan and the heating wire are both connected with the heat pipe 3.

Example 3

In the case structure of the large-capacity battery of the present embodiment, in addition to embodiment 1 or embodiment 2, a flame retardant is added to paraffin, and a weak portion 7 is provided on the wall of the inner case 6.

The number of the weak portions 7 may be 1, 2, 3 or more, and the weak portions 7 may be disposed at a certain portion of the wall of the inner housing 6, or may be uniformly distributed on the wall of the inner housing 6.

The flame retardant of this embodiment is a bromine-based flame retardant or a phosphorus-nitrogen-based flame retardant.

Preferably, the mass ratio of the paraffin wax to the flame retardant in the embodiment is: 2:1-4:1.

The weakened portion 7 of this embodiment is a fusible metal piece, a scored groove or a weakened hole. The thickness of the bottom wall of the scored groove or the thickness of the hole of the weak hole is one fourth to one sixth of the thickness of the wall of the inner housing 6.

The present embodiment provides a high-capacity battery case structure, which comprises the following steps: when the high-capacity battery works normally, because paraffin has high phase-change latent heat, heat generated by the high-capacity battery is absorbed by the latent heat of the paraffin in the paraffin layer, when the temperature of the paraffin layer rises or the paraffin is completely melted, the heat pipe 3 can conduct the heat in the paraffin layer to the outer side of the cavity structure for dissipation, and the paraffin layer and the heat pipe 3 are used for cooperatively dissipating heat to cool the high-capacity lithium battery; when paraffin melts completely, heat pipe 3 dispels the heat not in time, when leading to the inside thermal runaway that takes place of large capacity battery, constantly produce combustible gas in the 6 inner chambers of interior casing, pressure that leads to in the 6 inner chambers of interior casing rises constantly, when pressure reaches the limit, the weak part on the 6 inner walls of interior casing is opened, paraffin in the cavity structure carries the inner chamber that the fire retardant got into interior casing 6, because paraffin's resistance is big, and contain flame retardant material, can reduce the conducting capacity of battery electricity core, prevent the further stretching of battery out of control.

It should be noted that the heat conducting material of the present invention may also be graphite, copper powder, aluminum powder or carbon fiber. The utility model discloses a heat conduction working medium of filling notes in heat pipe 3 still can be for two kinds and the combination more than two kinds in alcohol, aqueous ammonia, pentane or freon 11 or acetone, water, alcohol, aqueous ammonia, pentane, freon 11, wherein, freon 11 is trichloro-monofluoromethane.

The foregoing is a further detailed description of the invention with reference to specific preferred embodiments and is not intended to limit the invention, to the extent that certain modifications or alterations may be made without departing from the spirit of the invention, any such modifications, equivalents, improvements, etc. as fall within the spirit and principles of the invention as defined by the appended claims.

Claims

1. A high-capacity battery shell structure is characterized by comprising a cavity structure, wherein a paraffin layer is filled in the cavity structure and used for absorbing heat generated by a battery during working;

the high-capacity battery shell structure also comprises an inner shell and an outer shell which are sequentially arranged from inside to outside, the cavity structure is arranged between the outer shell and the inner shell, and the inner cavity of the inner shell is used for placing a battery cell of a high-capacity battery;

a heat pipe is inserted in the paraffin layer;

the high-capacity battery shell structure further comprises an upper cover plate, the upper cover plate is arranged at the opening at the top of the outer shell and the inner shell, and the heat pipe penetrates through the upper cover plate and extends to the upper part of the upper cover plate to be connected with the refrigerating and heating module.

2. A large capacity battery case structure as set forth in claim 1, wherein said heat pipe has a plurality of heat pipes, and said plurality of heat pipes are juxtaposed.

3. A large capacity battery case structure as set forth in claim 1, wherein said heat pipe is attached to the outside of the wall of the inner case.

4. A large capacity battery case structure as set forth in claim 1, wherein said paraffin layer is a flame retardant paraffin layer, and one or more weak portions are provided on the wall of said inner case.

5. A large capacity battery case structure as set forth in claim 4, wherein said weak portion is a fusible metal piece, a scored groove or a weak hole.

6. A large capacity battery case structure as set forth in claim 1, wherein said outer case and said inner case are each of a cylindrical structure or a prismatic structure.