Thermal protection device of power battery

Abstract

The invention discloses a thermal protection device of a power battery. The thermal protection device comprises a battery placement tray and a thermal protection assembly, a plurality of through holes are formed in the battery placing tray, and are uniformly formed in the length direction and the width direction of the battery placing tray at intervals; the thermal protection assembly comprises an annular boss and a flame-retardant body, the annular boss is arranged at the bottom of the through hole, the interior of the through hole is used for placing a battery monomer, the bottom of the battery monomer abuts against the annular boss, the flame-retardant body wraps the battery monomer, and the flame-retardant body is matched with a gap formed between the through hole and the battery monomer. According to the invention, when a certain battery monomer on the battery placement tray is exploded due to a thermal event, the adjacent battery monomers can be protected from being influenced by high-temperature gas / solid after explosion through the flame-retardant body, and the plurality of battery monomers are separated by arranging the plurality of through holes in the battery placement tray, so that the battery can be conveniently stored. The subsequent battery monomer system can be conveniently returned to a factory for maintenance, and the maintenance cost is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicle batteries, and more specifically, to a thermal protection device for a power battery. Background Art

[0002] At present, the new energy vehicle market is booming, and China has become the world's largest new energy vehicle market. As the core component of electric vehicles, the safety of power batteries is the key to the development of new energy vehicles. Among the many battery system options, large cylindrical batteries are widely used due to their relatively small single-cell energy, reliable directional pressure relief, flexible arrangement, good heat dissipation, and high volume utilization. However, the battery system lacks effective thermal protection. When a thermal safety event occurs in a battery cell, the heat released will affect the surrounding cells, causing a chain reaction and leading to thermal runaway of the entire battery system.

[0003] With the development of various thermal protection methods for cylindrical battery systems, the risk of thermal runaway of battery systems has been greatly reduced. For example, the widely used polyurethane foam glue technology can fully fill the interior of the battery system, which can not only fix the battery cells and replace the brackets in the battery pack to insulate them from each other, but also isolate and buffer the battery cells. However, this solution will result in the battery pack as a whole. If there are quality problems with hundreds or thousands of battery cells in the pack, the possibility of subsequent repairs will be zero, which will place extremely high demands on the consistency of the battery cells and increase the cost of the battery pack.

[0004] Therefore, how to provide a thermal protection device for a power battery has become a technical problem that urgently needs to be solved in this field. Summary of the invention

[0005] An object of the present invention is to provide a new technical solution for a thermal protection device of a power battery.

[0006] According to a first aspect of the present invention, a thermal protection device for a power battery is provided, comprising: a battery placement tray and a thermal protection assembly; the battery placement tray is provided with a plurality of through holes, and the plurality of through holes are evenly spaced along the length direction and the width direction of the battery placement tray;

[0007] The heat protection component includes an annular boss and a flame retardant body, the annular boss is arranged at the bottom of the through hole, the interior of the through hole is used to place the battery cell, and the bottom of the battery cell abuts against the annular boss, the flame retardant body wraps the battery cell, and the flame retardant body cooperates with the gap formed between the through hole and the battery cell.

[0008] Optionally, the through hole and the annular boss are both dodecagonal structures.

[0009] Optionally, an explosion-proof valve is provided at the bottom of the battery cell, and at least a portion of the explosion-proof valve is located in the annular boss.

[0010] Optionally, the flame retardant is AB type organic silica gel.

[0011] Optionally, fixing blocks are provided on both sides of the battery placement tray, the fixing blocks are arranged at intervals along the length direction of the battery placement tray, and mounting holes are provided on the fixing blocks, and the battery placement tray is fixed by installing fastening bolts on the mounting holes.

[0012] Optionally, the heat protection assembly further includes arc-shaped guide fins, and the arc-shaped guide fins are spaced between the two groups of battery cells.

[0013] Optionally, the through holes include a first column and a second column arranged sequentially along the length direction of the battery placement tray, and the projection of the midpoint between two adjacent through holes in the first column coincides with the center of the through holes in the second column; the arc-shaped guide fins sequentially connect the midpoint between two adjacent through holes in the first column and the midpoint between two adjacent through holes in the second column to form an arc-shaped structure.

[0014] The beneficial effects of the present invention are:

[0015] The present invention provides a plurality of through holes on the battery placement tray, and the plurality of through holes are evenly spaced along the length direction and the width direction of the battery placement tray to separate a plurality of battery cells. If the battery cells have quality problems such as excessive pressure difference and excessive internal resistance, the manufacturer can only peel and replace the abnormal battery cells, which is convenient for the subsequent return of the battery cell system to the factory for repair, thereby greatly reducing the maintenance cost.

[0016] Moreover, the present application places the battery cell inside the through hole by setting an annular boss at the bottom of the through hole, and the bottom of the battery cell abuts against the annular boss, the flame retardant wraps the battery cell, and the flame retardant cooperates with the gap between the through hole and the battery cell. Therefore, when a battery cell on the battery placement tray explodes due to a thermal event, the flame retardant can protect the adjacent battery cells from being affected by the high-temperature gas / solid after the explosion.

[0017] Further features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0019] Figure 1This is a structural diagram of the thermal protection device for the power battery of the present invention;

[0020] Figure 2 It is a structural diagram of the through hole and the annular boss of the present invention;

[0021] Figure 3 is a cross-sectional view of the through hole and the annular boss of the present invention;

[0022] Figure 4 This is a structural diagram of pouring a flame retardant in a through hole.

[0023] The markings in the figure are as follows: 1. battery placement tray; 11. through hole; 2. thermal protection component; 21. annular boss; 22. flame retardant body; 3. fixing block; 4. arc-shaped guide fin; 5. battery cell. DETAILED DESCRIPTION

[0024] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0025] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0026] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0027] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0028] like Figures 1 to 4 As shown, an embodiment of the present invention provides a thermal protection device for a power battery, comprising: a battery placement tray 1 and a thermal protection component 2; a plurality of through holes 11 are arranged on the battery placement tray 1, and the plurality of through holes 11 are evenly spaced along the length direction and the width direction of the battery placement tray 1.

[0029] The thermal protection component 2 includes an annular boss 21 and a flame retardant body 22. The annular boss 21 is arranged at the bottom of the through hole 11. The inside of the through hole 11 is used to place the battery cell 5, and the bottom of the battery cell 5 is abutted against the annular boss 21. The flame retardant body 22 wraps the battery cell 5, and the flame retardant body 22 cooperates with the gap formed between the through hole 11 and the battery cell 5.

[0030] Specifically, the annular boss 21 has a thickness of 3 mm and a height of 1 mm. The diameter of the through hole 11 is larger than the diameter of the battery cell 5, so that after the battery cell 5 is placed inside the through hole 11, the flame retardant 22 can be poured between the through hole 11 and the battery cell 5 to fix and protect the battery cell 5.

[0031] During the installation of the battery cells 5, the battery cells 5 are first placed in the battery placement tray 1, and the bottom of the battery cells 5 abuts against the annular boss 21, so that the battery cells 5 can be stably placed in the through hole 11; then, Figure 4 As shown, the flame retardant 22 is added into the through hole 11 from the center position of the annular boss 21 , so that the flame retardant 22 is filled into the gap between the through hole 11 and the battery cell 5 .

[0032] The present invention provides a plurality of through holes 11 on the battery placement tray 1, and the plurality of through holes 11 are evenly spaced along the length direction and the width direction of the battery placement tray 1 to separate the plurality of battery cells 5. If the battery cells 5 have quality problems such as excessive pressure difference and excessive internal resistance, the manufacturer can only peel and replace the abnormal battery cells, which is convenient for the subsequent return of the battery cells 5 to the factory for repair, thereby greatly reducing the maintenance cost.

[0033] Moreover, the present application places the battery cell 5 inside the through hole 11 by setting the annular boss 21 at the bottom of the through hole 11, and the bottom of the battery cell 5 abuts against the annular boss 21, the flame retardant body 22 wraps the battery cell 5, and the flame retardant body 22 cooperates with the gap between the through hole 11 and the battery cell 5. Therefore, when a thermal event occurs to a battery cell 5 on the battery placement tray 1 and an explosion occurs, due to the action of the flame retardant body 22, the adjacent battery cells 5 can be protected from being affected by the high-temperature gas / solid after the explosion.

[0034] In one embodiment of the thermal protection device of the power battery of the present invention, Figure 2 and Figure 3 As shown, the through hole 11 and the annular boss 21 are both 12-sided structures.

[0035] Specifically, the through hole 11 and the annular boss 21 are both configured as a regular dodecagonal structure, which has good symmetry and aesthetics, and also enhances the structural strength of the battery placement tray 1 of the present invention.

[0036] In one embodiment of the thermal protection device of the power battery of the present invention, an explosion-proof valve is provided at the bottom of the battery cell 5 , and at least a part of the explosion-proof valve is located in the annular boss 21 .

[0037] Specifically, the explosion-proof valve is used to prevent the battery from exploding due to thermal runaway caused by overcharging, overdischarging or other abnormal conditions. The explosion-proof valve can monitor the pressure changes inside the battery and open when necessary to release the internal accumulated pressure, thereby protecting the battery cell 5 from damage.

[0038] In one embodiment of the thermal protection device of the power battery of the present invention, the flame retardant body 22 is AB type organic silicone, which can quickly fill the gap between the through hole 11 and the battery cell 5 and quickly solidify. In addition to its own viscosity, the solidified AB type organic silicone also cooperates with the annular boss 21 to have a glue locking effect, which can ensure that the battery system after grouping can pass the mechanical performance test and the AB type organic silicone does not fall off. It has the advantages of high bonding strength, good temperature resistance, moisture and water resistance, non-toxicity, tastelessness, and environmental protection.

[0039] In one embodiment of the thermal protection device of the power battery of the present invention, Figures 1 to 4 As shown, fixing blocks 3 are provided on both sides of the battery placement tray 1. The fixing blocks 3 are arranged at intervals along the length direction of the battery placement tray 1, and mounting holes are provided on the fixing blocks 3. The battery placement tray 1 is fixed by installing fastening bolts on the mounting holes.

[0040] The present invention arranges the fixing blocks 3 at intervals along the length direction of the battery placement tray 1, and arranges mounting holes on the fixing blocks 3. Fastening bolts are installed in the mounting holes to fix the battery placement tray 1 on the car, thereby effectively ensuring the stability of the installation of the thermal protection device of the power battery of the present invention.

[0041] In one embodiment of the thermal protection device of the power battery of the present invention, Figure 1 As shown, the heat protection assembly 2 further includes arc-shaped guide fins 4 , and the arc-shaped guide fins 4 are spaced between two groups of battery cells 5 .

[0042] The present invention designs arc-shaped guide fins 4 between the through holes 11 at the bottom of the battery placement tray 1. The direction of the arc-shaped guide fins 4 can be adjusted according to the exhaust direction of the battery placement tray 1, which has a guiding effect on the high-temperature gas after the explosion of the battery cell 5 and a blocking effect on some high-temperature solids, which not only reduces the subsequent maintenance cost of the battery pack, but also improves the safety of the battery pack.

[0043] In one embodiment of the thermal protection device for a power battery of the present invention, the through holes 11 include a first column and a second column arranged sequentially along the length direction of the battery placement tray 1, and the projection of the midpoint between two adjacent through holes 11 in the first column coincides with the center of the through holes 11 in the second column; the arc-shaped guide fins 4 sequentially connect the midpoint between two adjacent through holes 11 in the first column and the midpoint between two adjacent through holes 11 in the second column to form an arc-shaped structure.

[0044] Specifically, the through holes 11 are evenly spaced along the length direction and the width direction of the battery tray 1 , that is, the through holes 11 arranged along the length direction of the battery tray 1 are divided into a first column and a second column, and the first column and the second column are arranged sequentially.

[0045] The present invention forms an arc structure by aligning the projection of the midpoint between two adjacent through holes 11 in the first column with the center of the through hole 11 in the second column, and connecting the midpoint between two adjacent through holes 11 in the first column and the midpoint between two adjacent through holes 11 in the second column in sequence with the arc guide fin 4. The arc guide fin 4 provides thermal safety protection for the entire battery system, and in the absence of full filling with foam glue, it not only has flame retardant and heat insulation thermal protection, but also facilitates the subsequent replacement and maintenance of battery cells 5. Moreover, the conventional practice of full filling of foam glue in the battery pack is changed, which not only reduces the subsequent maintenance cost of the battery pack, but also improves the safety of the battery pack.

[0046] Although some specific embodiments of the present invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A thermal protection device for a power battery, characterized in that: include: A battery placement tray and a heat protection component; the battery placement tray is provided with a plurality of through holes, and the plurality of through holes are evenly spaced along the length direction and the width direction of the battery placement tray; The heat protection component includes an annular boss and a flame retardant body, the annular boss is arranged at the bottom of the through hole, the interior of the through hole is used to place the battery cell, and the bottom of the battery cell abuts against the annular boss, the flame retardant body wraps the battery cell, and the flame retardant body cooperates with the gap formed between the through hole and the battery cell.

2. The thermal protection device for a power battery according to claim 1, characterized in that: The through hole and the annular boss are both 12-sided structures.

3. The thermal protection device for a power battery according to claim 1, characterized in that: An explosion-proof valve is arranged at the bottom of the battery cell, and at least a part of the explosion-proof valve is located in the annular boss.

4. The thermal protection device for a power battery according to claim 1, characterized in that: The flame retardant is AB type organic silica gel.

5. The thermal protection device for a power battery according to claim 1, characterized in that: Fixing blocks are arranged on both sides of the battery placement tray. The fixing blocks are arranged at intervals along the length direction of the battery placement tray. Mounting holes are arranged on the fixing blocks. Fastening bolts are installed on the mounting holes to fix the battery placement tray.

6. The thermal protection device for a power battery according to claim 1, characterized in that: The heat protection assembly further includes arc-shaped guide fins, and the arc-shaped guide fins are spaced between the two groups of battery cells.

7. The thermal protection device for a power battery according to claim 6, characterized in that: The through holes include a first column and a second column arranged sequentially along the length direction of the battery placement tray, and the projection of the midpoint between two adjacent through holes in the first column coincides with the center of the through holes in the second column; the arc-shaped guide fins sequentially connect the midpoint between two adjacent through holes in the first column and the midpoint between two adjacent through holes in the second column to form an arc-shaped structure.

Images