Energy storage battery module based on forced air cooling type thermal management

Abstract

The application belongs to the technical field of battery thermal management, and relates to an energy storage battery module based on forced air cooling type thermal management, which comprises a module shell and a forced air cooling assembly. The module shell is sequentially divided into multiple phase change material areas along the cooling air flow direction. Each phase change material area is filled with phase change material. The filling amount of the phase change material in the multiple phase change material areas sequentially increases along the cooling air flow direction. The application sequentially divides multiple phase change material areas along the cooling air flow direction, and sequentially increases the filling amount of the phase change material in each area along the cooling air flow direction. The latent heat absorption capacity of the phase change material near the air outlet side is gradually enhanced, so that under the working condition that the heat exchange capacity of forced air cooling is attenuated due to the temperature rise of air along the pipeline, the change trend of the heat exchange capacity of the cooling air is matched by using the zoning configuration of the phase change material, and the temperature gradient along the airflow direction in the battery module is effectively inhibited.

Description

Technical Field

[0001] This invention belongs to the field of battery thermal management technology and relates to an energy storage battery module based on forced air cooling thermal management. Background Technology

[0002] With the continuous development of the new energy industry, energy storage battery modules are widely used in scenarios such as power peak shaving, renewable energy grid connection, and industrial energy storage. Energy storage battery modules are generally assembled from a large number of battery cells connected in series and parallel. Under high-rate charge and discharge conditions, a large amount of heat will be continuously generated inside the battery. The heat distribution state inside the module directly affects the cycle life, operational stability, and safety of the battery. Therefore, energy storage battery modules need to be equipped with a reliable thermal management system to control the module temperature rise and internal temperature distribution.

[0003] Currently, mainstream thermal management solutions for energy storage battery modules include forced air cooling, liquid cooling, phase change material (PCM) cooling, and a combination of air cooling and PCM cooling. Forced air cooling is widely used in the energy storage field due to its simple structure, low cost, and convenient maintenance. PCM, relying on its ability to absorb a large amount of latent heat during the phase change process, can suppress rapid temperature rise in the battery. Therefore, a composite thermal management solution has emerged in the industry that fills the gaps between battery cells with PCM and combines it with forced air cooling. This type of solution combines phase change heat storage with air convection heat transfer. The PCM absorbs the heat generated by the battery, and then the flowing cooling air carries away the heat, thereby achieving temperature control of the energy storage battery module.

[0004] However, as the cooling air continuously absorbs the heat released by the battery along the flow path, the air temperature gradually rises, and the temperature difference between the air and the battery continues to narrow. This causes the actual heat exchange capacity of the air along the airflow direction to continuously decrease, resulting in the continuous accumulation of heat on the air outlet side of the energy storage battery module. A significant temperature gradient in the airflow direction is formed inside the energy storage battery module, affecting the temperature consistency of each battery cell inside the energy storage battery module and reducing the safety performance of the energy storage battery module during high-rate charging and discharging operation. Summary of the Invention

[0005] The purpose of this invention is to provide an energy storage battery module based on forced air cooling thermal management, which can reduce the temperature gradient in the airflow direction inside the energy storage battery module, improve the temperature consistency between battery cells, and ensure the safety performance of the energy storage battery module under high-rate charging and discharging conditions.

[0006] To achieve the above objectives, the technical solution provided by the present invention is as follows: An energy storage battery module based on forced air cooling thermal management includes a module housing and a forced air cooling component. The module housing has an air inlet and an air outlet at its two ends, respectively. The forced air cooling component is connected to the air inlet and the air outlet, respectively. The forced air cooling component is used to drive cooling air into the module housing through the air inlet and out through the air outlet. The module housing is divided into multiple phase change material zones along the cooling air flow direction. Each phase change material zone is filled with phase change material. The amount of phase change material in the multiple phase change material zones increases sequentially along the cooling air flow direction to enhance the latent heat absorption capacity of the phase change material step by step along the cooling air flow direction.

[0007] The invention is further characterized by: The types of phase change materials are the same in several of the phase change material regions.

[0008] The multiple phase change material regions include at least a first phase change region, a second phase change region, and a third phase change region, which are arranged sequentially along the cooling air flow direction.

[0009] The module housing is divided into multiple height zones along the height direction of the battery cell, and phase change material is filled in each of the multiple height zones.

[0010] The phase change materials are paraffin-based phase change materials, organic composite phase change materials, or composite phase change materials with added high thermal conductivity fillers.

[0011] The module housing contains multiple battery cells arranged in a matrix. Phase change material is filled in the gaps between adjacent battery cells, and the gaps are connected along the direction of cooling air flow to form an air flow channel for cooling air circulation.

[0012] Each battery cell is connected to the phase change material via a thermally conductive structure.

[0013] The forced air cooling component includes a fan, with the fan outlet connected to the air inlet or the fan inlet connected to the air outlet.

[0014] The energy storage battery module based on forced air cooling thermal management of the present invention has the following advantages: This invention divides the cooling airflow direction into multiple phase change material zones, with the amount of phase change material in each zone increasing sequentially along the airflow direction. This gradually enhances the latent heat absorption capacity of the phase change material near the air outlet. Under the condition that forced air cooling reduces heat exchange capacity due to the temperature rise of the air along the flow path, the partitioned configuration of the phase change material matches the changing trend of the cooling air heat exchange capacity. This effectively suppresses the temperature gradient along the airflow direction inside the battery module, improves the temperature consistency between individual battery cells, and enhances the temperature uniformity and safety performance of the battery module during high-rate charging and discharging. Attached Figure Description

[0015] Figure 1 This is a top view of the structure of the present invention.

[0016] Figure 2 This is a cloud map showing the distribution of the cooling air velocity field in this invention.

[0017] Figure 3 This is a cloud map showing the distribution of the liquid phase fraction of the phase change material in this invention.

[0018] Figure 4 This is a cloud map showing the distribution of the temperature field in this invention.

[0019] Figure label: 1. Module housing, 2. Battery cell, 3. Air inlet, 4. Air outlet, 5. Phase change material, 6. First phase change zone, 7. Second phase change zone, 8. Third phase change zone, 9. Air flow channel. Detailed Implementation

[0020] The technical solutions of the present invention will now be described clearly and in detail with reference to the accompanying drawings. In the description of the embodiments of the present invention, unless otherwise stated, " / " indicates "or," for example, A / B can mean A or B. "And / or" in the text is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone. Furthermore, in the description of the embodiments of the present invention, "multiple" refers to two or more. The terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0021] like Figure 1As shown, the present invention provides an energy storage battery module based on forced air cooling thermal management, including a module housing 1 and a forced air cooling component. The two ends of the module housing 1 are respectively provided with an air inlet 3 and an air outlet 4. Multiple battery cells 2 are arranged in a matrix inside the module housing 1. The forced air cooling component is connected to the air inlet 3 and the air outlet 4 respectively. The forced air cooling component is used to drive cooling air into the module housing 1 through the air inlet 3 and out through the air outlet 4. The module housing 1 is divided into multiple phase change material zones along the cooling air flow direction. Each phase change material zone is filled with phase change material 5. The filling amount of phase change material 5 in the multiple phase change material zones increases sequentially along the cooling air flow direction to enhance the latent heat absorption capacity of the phase change material 5 step by step along the cooling air flow direction. This invention divides the cooling airflow direction into multiple phase change material zones, and increases the amount of phase change material in each zone sequentially along the airflow direction. This gradually enhances the latent heat absorption capacity of the phase change material near the air outlet 4. Under the condition that forced air cooling reduces heat exchange capacity due to the temperature rise of the air along the flow path, the partitioned configuration of the phase change material matches the changing trend of the cooling air heat exchange capacity. This effectively suppresses the temperature gradient along the airflow direction inside the battery module, improves the temperature consistency between individual battery cells 2, and enhances the temperature uniformity and safety performance of the battery module during high-rate charging and discharging.

[0022] In this design, the phase change material 5 in multiple phase change material zones is of the same type. This allows the phase change material 5 to form a heat storage structure with consistent material and differentiated filling amounts within the module housing 1 along the cooling airflow direction. While ensuring that the phase change material 5 in each zone has the same phase change temperature range and heat storage capacity per unit mass, the heat transfer capacity reduction caused by the temperature rise along the cooling airflow can be achieved simply by adjusting the filling amount of the phase change material 5 in different zones. This avoids the complexity of selecting multiple materials with different phase change temperatures and the interface compatibility issues, reducing the preparation cost and filling process difficulty of the phase change material 5. Simultaneously, it ensures the consistency of phase change temperature response in each phase change material zone, allowing the heat generated by the battery cell 2 to be stably absorbed by the phase change material 5 at different airflow locations, suppressing the temperature gradient along the airflow direction of the battery module, and improving the temperature consistency between the battery cells 2.

[0023] like Figure 1As shown, the multiple phase change material regions include at least a first phase change region 6, a second phase change region 7, and a third phase change region 8, which are arranged sequentially along the cooling airflow direction. This allows the phase change material 5 to form a multi-level heat storage structure along the airflow direction within the module housing 1. The first phase change region 6 provides basic heat absorption buffering on the inlet side where the air temperature is lower; the second phase change region 7 supplements the heat storage of the continuously heating air in the middle region; and the third phase change region 8 concentrates on enhancing latent heat absorption on the outlet side where the air heat exchange capacity is weakest. This allows the heat storage capacity of each phase change material region to be matched stepwise with the heat exchange capacity of the cooling air as it decreases along the flow path, suppressing heat accumulation on the outlet side, reducing the temperature gradient along the airflow direction inside the module housing 1, and improving the temperature consistency between the individual battery cells 2.

[0024] like Figure 1 As shown, the module housing 1 is divided into multiple height zones along the height direction of the battery cell 2, and the phase change material 5 is filled in each of these zones. This allows the phase change material 5 to cover different areas along the height direction of the battery cell 2, enabling the synchronous absorption and storage of heat generated at different heights during battery module operation. This avoids the temperature gradient along the height direction caused by the natural rise of hot air, which leads to heat accumulation in the upper part of the module housing 1 and insufficient heat in the lower part. This improves the uniformity of temperature distribution along the height direction, ensures temperature consistency of the battery cell 2 at different heights, and enhances the overall thermal stability of the battery module during continuous operation.

[0025] like Figure 1 As shown, the phase change material 5 is a paraffin-based phase change material, an organic composite phase change material, or a composite phase change material with added high thermal conductivity fillers. Among them, paraffin-based phase change materials and organic composite phase change materials have the characteristics of high latent heat of phase change, small volume change during phase change, stable chemical properties, and no corrosiveness when in contact with battery cell 2, which can ensure the stable performance of heat storage of phase change material 5 during long-term cycle use. The composite phase change material with added high thermal conductivity fillers retains a high latent heat of phase change while significantly improving the overall thermal conductivity of the material, so that the heat generated by battery cell 2 can be transferred to the interior of phase change material 5 more quickly and stimulate its phase change heat storage process, thereby improving the response speed and heat absorption efficiency of phase change material 5 under transient thermal shock conditions of battery module, and enhancing the thermal management reliability of battery module during continuous high-rate charge and discharge process.

[0026] like Figure 1As shown, the phase change material 5 fills the gap between adjacent battery cells 2, and the gap is continuous along the direction of cooling air flow to form an airflow channel 9 for cooling air circulation. This allows the phase change material 5 and the cooling air to form a synergistic heat dissipation structure in the same gap space on both sides of the battery cell 2. The phase change material 5 adheres to the side wall surface of the battery cell 2 and directly absorbs most of the heat generated by the battery operation. The remaining heat is removed from the inside of the module housing 1 by the cooling air flowing through the airflow channel 9 through convection heat exchange. The heat stored in the phase change material 5 can also be continuously discharged through the cooling air flowing in the airflow channel 9. Thus, during the operation of the battery module, the phase change heat storage and forced convection heat exchange are coordinated in real time, improving the overall heat dissipation efficiency and temperature control capability of the battery module thermal management system.

[0027] like Figure 1 As shown, each battery cell 2 is connected to the phase change material 5 via a thermally conductive structure. This allows the heat generated during the operation of the battery cell 2 to be rapidly transferred to the interior of the phase change material 5 through the thermally conductive structure, shortening the heat transfer path and time from the surface of the battery cell 2 to the center of the phase change material 5. This prevents a large amount of heat from accumulating on the sidewall surface of the battery cell 2. After receiving heat, the phase change material 5 undergoes a phase change and stores latent heat. Some of the stored heat is then fed back to the surface of the battery cell 2 through the thermally conductive structure and carried away by the cooling air flowing through the airflow channel 9. The thermally conductive structure also reduces the contact thermal resistance between the battery cell 2 and the phase change material 5, improves the heat exchange efficiency between them, ensures that the latent heat storage capacity of the phase change material 5 is fully utilized, and enhances the battery module's ability to withstand transient thermal shocks under high heat flux density conditions.

[0028] like Figure 1 As shown, the forced air cooling component includes a fan, with the fan outlet connected to the air inlet 3 or the fan inlet connected to the air outlet 4. This allows the fan to flexibly select between blowing and exhaust drive modes according to the actual heat dissipation requirements of the battery module. When the fan outlet is connected to the air inlet 3, cooler external air is forced into the module housing 1 and flows evenly through the airflow channels 9 between the individual battery cells 2 under positive pressure, which helps improve the uniformity of airflow distribution. When the fan inlet is connected to the air outlet 4, hot air inside the module housing 1 is actively extracted, and under negative pressure, external cooling air naturally replenishes the module housing 1 and flows through the airflow channels 9, which helps suppress the stagnation and backflow of hot air in the module housing 1. Both connection methods ensure that cooling air continuously flows through the gaps between the individual battery cells 2 and carries away heat, enhancing the adaptability and heat dissipation reliability of the battery module under different operating conditions.

[0029] Working principle: During operation, the battery cells 2 generate heat, and the forced air cooling component drives external cooling air to enter the module housing 1 through the air inlet 3. The cooling air flows along the air flow channel 9, exchanges heat with the surfaces of multiple battery cells 2, carries away some of the heat generated during the operation of the battery cells 2, and is finally discharged through the air outlet 4. At the same time, when the battery cells 2 generate instantaneous high heat flow, the phase change material 5 filled in the gaps between adjacent battery cells 2 absorbs heat and stores thermal energy through the phase change process, reducing the rate of temperature rise of the battery cells 2. Since the cooling air gradually rises in temperature and its heat exchange capacity continuously decreases due to heat absorption along the flow direction, this invention adopts a first phase change zone 6, a second phase change zone 7, and a third phase change zone 8 arranged sequentially along the cooling air flow direction, and the amount of phase change material 5 in each zone increases sequentially along the cooling air flow direction, so that the latent heat absorption capacity of the phase change material 5 on the outlet side is gradually enhanced. The phase change material 5 can adjust the heat according to the heat load difference of different areas.

[0030] Figure 2 The cooling air velocity field distribution cloud map shown reflects the state of cooling air entering the air flow channel 9 from the air inlet 3 and flowing along the channel direction. The cooling air forms a continuous air flow field inside the module housing 1 to achieve synchronous cooling of multiple battery cells 2. Figure 3 The phase change material liquid phase distribution cloud map shown reflects the phase change material 5 gradually undergoing phase change after absorbing the heat released by the battery during battery operation. The phase change material 5 in different phase change material regions shows different phase change degrees due to different heat loads at their locations. Among them, the third phase change region 8 has a higher heat accumulation and the largest filling amount on the side closer to the air outlet 4, and its phase change response is more obvious. Figure 4 The temperature field distribution cloud map shown reflects the internal temperature distribution of the battery module after the use of partitioned phase change materials to assist forced air cooling. The internal temperature distribution of the battery module is more uniform, and local high temperature areas are effectively suppressed.

[0031] By combining forced air cooling with zoned phase change thermal storage, this invention can effectively reduce the maximum temperature during battery module operation, reduce the temperature difference between individual battery cells 2, suppress heat accumulation on the outlet side, and improve the temperature uniformity and safety performance of the battery module during operation.

[0032] The energy storage battery module based on forced air cooling thermal management of the present invention has the following other advantages: First, this invention introduces a partitioned phase change material configuration along the cooling air flow direction on the basis of the traditional forced air cooling structure. This makes the heat storage capacity of the phase change material match the trend of the heat exchange capacity of the cooling air decreasing due to the temperature rise along the flow path. This allows for the configuration of less phase change material in areas with strong heat exchange capacity on the inlet side and more phase change material in areas with weak heat exchange capacity on the outlet side. This avoids the problem of phase change material in some areas completing phase change too early or failing to fully participate in heat storage in the uniform arrangement method.

[0033] Secondly, by increasing the amount of phase change material filling in the outlet area, the latent heat absorption capacity of the phase change material on the outlet side is enhanced. The larger amount of phase change material in the outlet area provides a stronger heat buffer in the area where the cooling air heat exchange capacity is weakest, effectively suppressing the heat accumulation on the air outlet side caused by the rise in air temperature.

[0034] Third, this invention combines forced air cooling with partitioned phase change heat storage. The cooling air flowing in the air flow channel carries away part of the heat generated by the battery cells from the inside of the module housing through forced convection heat exchange. At the same time, the phase change material filled in the gap between adjacent battery cells stores another part of the heat through the phase change process. The two thermal management methods work together in the same gap space to reduce the temperature difference between battery cells and improve the temperature uniformity and safety of the battery module during operation.

[0035] Fourth, the present invention does not require the addition of complex liquid cooling equipment such as liquid cooling plates and compressors. It can improve thermal management performance simply by filling the gaps between adjacent battery cells inside the module housing with phase change material and cooperating with forced air cooling components. It improves the temperature distribution of the battery module without significantly increasing the total amount of phase change material used, and has good engineering applicability and economy.

[0036] It is understood that this invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this invention. Furthermore, under the teachings of this invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of this invention. Therefore, this invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this invention are within the protection scope of this invention.

Claims

1. An energy storage battery module based on forced air cooling thermal management, comprising a module housing and a forced air cooling component, wherein an air inlet and an air outlet are respectively provided at both ends of the module housing, and the forced air cooling component is connected to the air inlet and the air outlet respectively, wherein the forced air cooling component is used to drive cooling air into the module housing from the air inlet and out from the air outlet, characterized in that, The module housing is divided into multiple phase change material zones along the cooling airflow direction. Each phase change material zone is filled with phase change material, and the amount of phase change material in the multiple phase change material zones increases sequentially along the cooling airflow direction to enhance the latent heat absorption capacity of the phase change material step by step along the cooling airflow direction.

2. The energy storage battery module based on forced air cooling thermal management according to claim 1, characterized in that, The phase change materials in multiple phase change material regions are of the same type.

3. The energy storage battery module based on forced air cooling thermal management according to claim 1, characterized in that, The plurality of phase change material regions include at least a first phase change region, a second phase change region, and a third phase change region, which are arranged sequentially along the cooling air flow direction.

4. The energy storage battery module based on forced air cooling thermal management according to claim 1, characterized in that, The module housing is divided into multiple height zones along the height direction of the battery cell, and the phase change material is filled in each of the multiple height zones.

5. The energy storage battery module based on forced air cooling thermal management according to claim 1, characterized in that, The phase change material is a paraffin-based phase change material, an organic composite phase change material, or a composite phase change material with added high thermal conductivity fillers.

6. The energy storage battery module based on forced air cooling thermal management according to claim 1, characterized in that, The module housing contains a matrix of battery cells, with the phase change material filling the gaps between adjacent battery cells. These gaps are connected along the direction of cooling airflow to form airflow channels for cooling air circulation.

7. The energy storage battery module based on forced air cooling thermal management according to claim 6, characterized in that, Each of the battery cells is connected to the phase change material via a thermally conductive structure.

8. The energy storage battery module based on forced air cooling thermal management according to claim 1, characterized in that, The forced air cooling component includes a fan, wherein the outlet of the fan is connected to the air inlet or the inlet of the fan is connected to the air outlet.

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