A safe sodium-ion battery

Abstract

The utility model discloses a safe sodium ion battery, including battery body. The utility model discloses, through the heat dissipation system of the inclination ventilation hole and multiple first group cavity coupling, utilize the principle of natural convection and realize sustained heat dissipation, combine the high heat capacity characteristic of phase change material nanometer composite PCM and quickly absorb heat when battery temperature sudden rise, and the automatic release of flame retardant in the thermal runaway stage simultaneously, form triple synergistic protection, solved the technical problem of traditional encapsulation battery low heat dissipation efficiency, high temperature heat accumulation and thermal runaway, adopt integrated heat dissipation - damping - flame retardant integrated structure, discarded motor drive heat dissipation fan blade, mechanical linkage damping component etc. Redundant design, through the built -in encapsulation of phase change material and flame retardant, guarantee heat dissipation efficiency and security while, battery volume increment is little, give consideration to miniaturization and high security demand, overcome the volume expansion and energy density drop problem of traditional scheme because of complex structure.

Description

Technical Field

[0001] This utility model relates to the field of sodium-ion battery technology, and in particular to a safe sodium-ion battery. Background Technology

[0002] Sodium-ion batteries are a type of rechargeable battery that primarily relies on the movement of sodium ions between the positive and negative electrodes to function. Existing sodium-ion batteries generally suffer from low safety. While they are typically encapsulated in a casing for protection, the casing can be subjected to frequent vibrations during normal use, leading to prolonged shocks and potential damage to the internal sodium-ion batteries. Furthermore, the poor heat dissipation of ordinary sodium-ion batteries encapsulated in the casing results in high internal temperatures, also contributing to damage. To address this, a publicly available technology proposes a high-safety sodium-ion battery, comprising a sodium-ion battery case. The bottom of the battery case is fixedly connected to a shock-absorbing base. The top of the shock-absorbing base has two parallel sliding grooves. A shock-absorbing plate is positioned above the shock-absorbing base. The bottom of the shock-absorbing plate is fixedly connected to two parallel fixing strips. Movable rods are rotatably connected to both sides of the two fixing strips. A rotating shaft is fixedly connected to the end of each of the four movable rods. Sliding blocks are rotatably connected to the outer diameter of each of the four rotating shafts, and these sliding blocks slide within the sliding grooves. The disclosed technology states that by working together, the shock-absorbing base, shock-absorbing plate, fixing strip, movable rod, sliding block and spring can provide a certain degree of protection for the sodium-ion battery on the shock-absorbing plate. By working together, the heat dissipation base, motor, heat dissipation fan blades, heat dissipation holes, copper heat dissipation pipe and heat dissipation fins can achieve a heat dissipation effect and protect the sodium-ion battery.

[0003] However, the aforementioned disclosed technologies have significant drawbacks: structural redundancy and space constraints. The mechanical linkage structures such as the shock-absorbing base, sliding groove, and movable rod require a large amount of space in the outer diameter direction of the battery body, resulting in a significant increase in battery volume, which contradicts the development trend of miniaturization and integration of sodium-ion batteries. Furthermore, its active heat dissipation design has flaws: setting a motor-driven heat dissipation fan blade inside the sodium-ion battery packaging shell not only increases energy consumption by an additional 5%-8%, but the micro motor also has heat dissipation problems, while greatly increasing the overall weight of the battery and significantly reducing portability.

[0004] Therefore, it is necessary to further optimize and improve the structure of sodium-ion batteries to enhance their heat dissipation and safety. Utility Model Content

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a safe sodium-ion battery.

[0006] To achieve the above objectives, this utility model adopts the following technical solution: a safe sodium-ion battery, comprising a battery body, with a positive electrode and a negative electrode at its upper and lower ends, respectively. A shell is provided on the outer wall of the battery body, and a heat-conducting pipe is fixedly connected between the shell and the battery body. An upper cover and a lower cover are fixedly connected at the upper and lower ends of the shell, respectively. A base is fixedly connected to the end of the lower cover away from the shell. Multiple upper and lower ventilation holes are provided on the circumferential sidewalls of the upper and lower covers, respectively. The upper and lower ventilation holes are arranged in a ring array. Multiple sets of vertically penetrating first, second, and third passage cavities are provided on the inner wall of the heat-conducting pipe. The two ends of the first passage cavity penetrate the interior of the upper and lower covers, respectively. The second passage cavity is filled with nano-composite PCM, and the third passage cavity is filled with powdered flame retardant. The upper and lower ends of the second and third passage cavities are sealed with UV adhesive.

[0007] As a further description of the above technical solution:

[0008] The central axis of the upper ventilation hole extends radially outward and obliquely upward toward the battery body, and the central axis of the upper ventilation hole makes an angle of 55°-65° with the horizontal plane. The central axis of the lower ventilation hole extends radially outward and obliquely downward toward the battery body, and the central axis of the lower ventilation hole makes an angle of 55°-65° with the horizontal plane.

[0009] As a further description of the above technical solution:

[0010] The upper ventilation hole, lower ventilation hole, and first passage cavity together form a V-shaped convection channel.

[0011] As a further description of the above technical solution:

[0012] Multiple sets of the first, second, and third passage cavities are distributed alternately.

[0013] As a further description of the above technical solution:

[0014] An elastic layer is provided between the battery body and the top cover. The positive electrode of the battery body penetrates the inner wall of the elastic layer and the upper wall of the top cover and extends to the top of the top cover.

[0015] As a further description of the above technical solution:

[0016] A conductive layer is fixedly provided on the lower wall of the base, the upper wall of the conductive layer abuts against the negative electrode of the battery body, and the lower wall of the conductive layer protrudes from the lower wall of the base.

[0017] As a further description of the above technical solution:

[0018] The outer shell and heat pipe are both made of aluminum alloy.

[0019] This utility model has the following beneficial effects:

[0020] 1. Compared with existing technologies, this safe sodium-ion battery uses a heat dissipation system coupled with inclined ventilation holes and multiple sets of first passage cavities to achieve continuous heat dissipation through the principle of natural convection. Combined with the high heat capacity characteristics of phase change material nanocomposite PCM, it can quickly absorb heat when the battery temperature rises sharply. At the same time, the flame retardant is automatically released during the thermal runaway stage, forming a triple synergistic protection, which solves the technical problems of low heat dissipation efficiency, high temperature heat accumulation and thermal runaway of traditional packaged batteries.

[0021] 2. Compared with existing technologies, this safe sodium-ion battery adopts an integrated heat dissipation-shock absorption-flame retardant structure, which eliminates redundant designs such as motor-driven heat dissipation fan blades and mechanical linkage shock absorption components. Through the built-in encapsulation of phase change materials and flame retardants, the battery volume increases only slightly while ensuring heat dissipation efficiency and safety. It takes into account both miniaturization and high safety requirements, and overcomes the problems of volume expansion and energy density reduction caused by complex structures in traditional solutions. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of a safe sodium-ion battery proposed in this utility model.

[0023] Figure 2 This is a schematic cross-sectional view of the overall structure of a safe sodium-ion battery proposed in this utility model;

[0024] Figure 3 This invention proposes a safe sodium-ion battery. Figure 2 A magnified view of a section at point A in the middle;

[0025] Figure 4 This invention proposes a safe sodium-ion battery. Figure 2 A magnified view of a section at point B in the middle;

[0026] Figure 5 This is a top sectional view of the heat pipe of a safe sodium-ion battery proposed in this utility model.

[0027] Legend:

[0028] 1. Battery body; 2. Outer shell; 3. Top cover; 4. Bottom cover; 5. Base; 6. Top ventilation hole; 7. Bottom ventilation hole; 8. Conductive layer; 9. Elastic layer; 10. Heat pipe; 11. First cavity; 12. Second cavity; 13. Third cavity; 14. Nanocomposite PCM; 15. Powder flame retardant. Detailed Implementation

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0030] Reference Figures 1 to 5 The present invention provides a safe sodium-ion battery: including a battery body 1, with a positive electrode and a negative electrode at the upper and lower ends of the battery body 1, respectively;

[0031] In order to achieve efficient heat dissipation and lightweight packaging of the battery body 1, an outer shell 2 is provided on the outer wall of the battery body 1, and a heat pipe 10 is fixedly connected between the outer shell 2 and the battery body 1. Both the outer shell 2 and the heat pipe 10 are aluminum alloy tubes.

[0032] The aluminum alloy shell 2 and the heat pipe 10 are in direct contact with the surface of the battery body 1, forming a continuous heat dissipation path. At the same time, the low density of aluminum alloy is used to control the overall weight increase of the packaging structure to within 105%.

[0033] To ensure the stability of the electrode connection and buffer external vibration and impact, the upper cover 3 and the lower cover 4 are fixedly connected to the upper and lower ends of the outer shell 2, respectively. The lower cover 4 is fixedly connected to the bottom support 5 at the end away from the outer shell 2. An elastic layer 9 is provided between the battery body 1 and the upper cover 3. The positive electrode of the battery body 1 penetrates the inner wall of the elastic layer 9 and the upper wall of the upper cover 3 and extends to the top of the upper cover 3. A conductive layer 8 is fixedly provided on the lower wall of the bottom support 5. The upper wall of the conductive layer 8 abuts against the negative electrode of the battery body 1, and the lower wall of the conductive layer 8 protrudes from the lower wall of the bottom support 5.

[0034] The elastic layer 9 absorbs kinetic energy through elastic deformation when the battery body 1 is vibrated, preventing the positive electrode from breaking due to hard collision with the top cover 3. At the same time, the protruding design of the conductive layer 8 ensures low-impedance contact between the negative electrode and the external circuit.

[0035] To enhance the efficiency of natural convection heat dissipation and construct a directional airflow channel, the upper cover 3 and the lower cover 4 are provided with multiple upper ventilation holes 6 and lower ventilation holes 7 on their circumferential sidewalls, respectively. The upper ventilation holes 6 and lower ventilation holes 7 are distributed in a ring array. The inner wall of the heat pipe 10 is provided with multiple sets of vertically penetrating first cavities 11. The two ends of the first cavities 11 penetrate the interior of the upper cover 3 and the lower cover 4, respectively. The central axis of the upper ventilation hole 6 extends radially outward and obliquely upward toward the battery body 1, and the central axis of the upper ventilation hole 6 makes an angle of 60° with the horizontal plane. The central axis of the lower ventilation hole 7 extends radially outward and obliquely downward toward the battery body 1, and the central axis of the lower ventilation hole 7 makes an angle of 60° with the horizontal plane. The upper ventilation holes 6, lower ventilation holes 7 and the first cavities 11 together form a V-shaped convection channel.

[0036] When the battery body 1 heats up, the V-shaped convection channel, based on the principle of hot air rising, drives cold air to enter from the lower ventilation hole 7 and hot air to exit from the upper ventilation hole 6, forming a self-circulating airflow that can achieve continuous heat dissipation without additional energy consumption.

[0037] In order to absorb heat instantly and slow down the rate of temperature rise under high temperature conditions, the inner wall of the heat pipe 10 is provided with multiple sets of vertically connected second cavities 12, and the second cavities 12 are filled with nano-composite PCM 14.

[0038] When the temperature of the battery body 1 exceeds 50℃, the nanocomposite PCM14 undergoes a solid-liquid phase transition, rapidly absorbing the heat conducted by the surface of the battery body 1, and controlling the local temperature fluctuation within the range of ±3℃.

[0039] In order to actively suppress the spread of flame during the thermal runaway stage, the inner wall of the heat pipe 10 is provided with multiple sets of vertically connected third cavities 13. The third cavities 13 are filled with powdered flame retardant 15, and the upper and lower ends of the second cavities 12 and the third cavities 13 are sealed with UV adhesive.

[0040] When the internal temperature of the battery body 1 exceeds 120°C, the UV adhesive decomposes due to heat, and the powdered flame retardant 15 is released from the third cavity 13 and covers the surface of the battery body 1, thus blocking the combustion chain reaction.

[0041] In order to optimize the multi-cavity layout and balance the functions of heat dissipation, heat storage and flame retardancy, multiple sets of first cavities 11, second cavities 12 and third cavities 13 are distributed in an alternating interval;

[0042] The alternating cavities allow for uniform coverage of heat dissipation airflow, phase change materials, and flame retardants around the battery body, avoiding blind spots.

[0043] Working principle: The aluminum alloy shell 2 and the heat pipe 10 directly contact the surface of the battery body 1, forming a continuous heat dissipation path. Simultaneously, the low density of the aluminum alloy keeps the overall weight increase of the packaging structure within 105%. The elastic layer 9 absorbs kinetic energy through elastic deformation when the battery body 1 is vibrated, preventing the positive electrode from breaking due to a hard collision with the top cover 3. Meanwhile, the protruding design of the conductive layer 8 ensures low-impedance contact between the negative electrode and the external circuit. When the battery body 1 heats up, the V-shaped convection channel, based on the principle of hot air rising, drives cool air to enter through the lower ventilation hole 7 and hot air to exit through the upper ventilation hole 6, forming a self-circulating airflow that achieves continuous heat dissipation without additional energy consumption. When the battery body 1 heats up, the V-shaped convection channel, based on the principle of hot air rising, drives cool air to enter through the lower ventilation hole 7 and hot air to exit through the upper ventilation hole 6, forming a self-circulating airflow that achieves continuous heat dissipation without additional energy consumption. When the temperature of the battery body 1 exceeds 50°C, the nanocomposite PCM14 undergoes a solid-liquid phase change, rapidly absorbing the heat conducted from the surface of the battery body 1 and controlling the local temperature fluctuation within ±3°C. When the internal temperature of the battery body 1 exceeds 120°C, the UV adhesive decomposes upon heating, and the powdered flame retardant 15 is released from the third cavity 13 and covers the surface of the battery body 1, blocking the combustion chain reaction. In order to optimize the multi-cavity layout to balance heat dissipation, heat storage and flame retardant functions, multiple sets of first cavities 11, second cavities 12 and third cavities 13 are alternately distributed. The alternating distribution of cavities ensures that the heat dissipation airflow, phase change material and flame retardant are uniformly covered around the battery body 1, avoiding blind spots.

[0044] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A safe sodium-ion battery, characterized in that: The battery includes a battery body (1), with a positive electrode at the top and a negative electrode at the bottom. A shell (2) is provided on the outer wall of the battery body (1). A heat pipe (10) is fixedly connected between the shell (2) and the battery body (1). An upper cover (3) and a lower cover (4) are fixedly connected to the top and bottom of the shell (2), respectively. A base (5) is fixedly connected to the end of the lower cover (4) away from the shell (2). Multiple upper ventilation holes (6) and lower ventilation holes (7) are provided on the circumferential sidewalls of the upper cover (3) and lower cover (4), respectively. The upper ventilation hole (6) and the lower ventilation hole (7) are arranged in a ring array. The inner wall of the heat pipe (10) is provided with a number of vertically connected first cavity (11), second cavity (12) and third cavity (13). The two ends of the first cavity (11) are respectively connected to the interior of the upper cover (3) and the lower cover (4). The second cavity (12) is filled with nano-composite PCM (14). The third cavity (13) is filled with powder flame retardant (15). The upper and lower ends of the second cavity (12) and the third cavity (13) are sealed with UV adhesive.

2. The safe sodium-ion battery according to claim 1, characterized in that: The central axis of the upper ventilation hole (6) extends radially outward and obliquely upward toward the battery body (1), and the central axis of the upper ventilation hole (6) makes an angle of 55°-65° with the horizontal plane. The central axis of the lower ventilation hole (7) extends radially outward and obliquely downward toward the battery body (1), and the central axis of the lower ventilation hole (7) makes an angle of 55°-65° with the horizontal plane.

3. A safe sodium-ion battery according to claim 1, characterized in that: The upper ventilation hole (6), the lower ventilation hole (7), and the first passage cavity (11) together form a V-shaped convection channel.

4. A safe sodium-ion battery according to claim 1, characterized in that: Multiple sets of the first through cavity (11), the second through cavity (12) and the third through cavity (13) are distributed alternately.

5. A safe sodium-ion battery according to claim 1, characterized in that: An elastic layer (9) is provided between the battery body (1) and the top cover (3). The positive electrode of the battery body (1) penetrates the inner wall of the elastic layer (9) and the upper wall of the top cover (3) and extends to the top of the top cover (3).

6. A safe sodium-ion battery according to claim 1, characterized in that: A conductive layer (8) is fixedly provided on the lower wall of the base (5). The upper wall of the conductive layer (8) abuts against the negative electrode of the battery body (1), and the lower wall of the conductive layer (8) protrudes from the lower wall of the base (5).

7. A safe sodium-ion battery according to claim 1, characterized in that: Both the outer shell (2) and the heat pipe (10) are aluminum alloy pipes.

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