Low-temperature lithium battery module capable of improving preheating efficiency

Abstract

The invention discloses a low-temperature lithium battery module capable of improving preheating efficiency, the battery module comprises a battery cell assembly and a built-in heat management device, the heat management device comprises at least one heating assembly and a sensing device, the module further comprises a battery management system used for controlling the working state of the heating element and monitoring the charging and discharging state of the battery module, the heating assembly is arranged between the adjacent battery cell assemblies, and the sensing device is arranged inside or on the outer surface of each battery cell assembly. The battery cell assemblies form preset voltage and capacity in a series connection and parallel connection mode, the module is provided with a built-in heat management system, the heating assemblies are arranged at the adjacent positions of the battery cell assemblies, the temperature sensors are arranged on the surfaces or in the battery cell assemblies, and the device is rapid in preheating response and improves the battery performance in the low-temperature environment; the heat transfer efficiency is maximized due to the optimized arrangement mode of the battery cell components; the battery management system has a preset preheating program and automatically controls the heating element.

Description

Technical Field

[0001] The present invention belongs to the technical field of lithium batteries, and in particular relates to a low-temperature lithium battery module with improved preheating efficiency. Background Art

[0002] The lithium battery module in the prior art has the problem of low preheating efficiency when working in a low temperature environment, resulting in slow charging or reduced discharge capacity, affecting the performance and service life of the lithium battery module. In a low temperature environment, the performance of the lithium battery module will be affected and the charging and discharging efficiency will decrease. Therefore, effective preheating measures are required to ensure its normal operation. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a low-temperature lithium battery module with improved preheating efficiency. The module has high preheating efficiency and can quickly increase the temperature of the battery cell components in a low temperature environment, thereby improving the charging and discharging performance of the battery.

[0004] The technical solution of the present invention is as follows: a low-temperature lithium battery module with improved preheating efficiency, the battery module comprising a battery cell assembly and a built-in thermal management device, the thermal management device comprising at least one heating component and a sensor device, the module also comprising a battery management system for controlling the working state of the heating element and monitoring the charge and discharge state of the battery module, the heating component is arranged between adjacent battery cell assemblies, and the sensor device is arranged inside or on the outer surface of each battery cell assembly.

[0005] Based on the above technical features, the battery cell components form a predetermined voltage and capacity by connecting in series and in parallel. The module has a built-in thermal management system for quickly preheating the battery cell components in a low temperature environment. The heating component is arranged at an adjacent position of the battery cell components for directly heating the battery cell components. The temperature sensor is arranged on the surface or inside of each battery cell component for real-time monitoring of the temperature of the battery cell components. The temperature sensor adopts an NTC thermistor, which is arranged on the surface or inside of each battery cell component for real-time monitoring and feedback of the temperature of the battery cell components.

[0006] As an improvement of the present invention, the heating element is a flexible heating film.

[0007] Based on the above technical features, the heating element is a flexible heating film that can fit the shape of the battery cell assembly. The flexible heating film is arranged between the battery cell assemblies and applied on the battery cell assemblies to achieve uniform heating.

[0008] As an improvement of the present invention, the flexible heating film is a filament-like or strip-like structure, forming a plurality of flexible heating films with filament-like or strip-like structures that are evenly distributed.

[0009] As an improvement of the present invention, the flexible heating film includes a flexible base layer, a conductive layer, an insulating layer and a protective layer, the conductive layer is arranged on the insulating layer, the protective layer covers the conductive layer, the conductive layer is composed of metal, carbon-based material or a mixture thereof, and the conductive layer has a serpentine or spiral structure.

[0010] Based on the above technical features, the conductive layer is arranged on the insulating layer to generate heat when power is turned on; the protective layer covers the conductive layer to improve the durability and protection of the heating film; the conductive layer adopts a serpentine or spiral layout to improve the heating efficiency; the protective layer adopts wear-resistant material to enhance the mechanical strength of the heating film.

[0011] As an improvement of the present invention, the insulating layer is composed of a multi-layer structure, including a bottom insulating film and a top insulating film covering the conductive layer.

[0012] As an improvement of the present invention, the protective layer includes a transparent protective film, which allows the heating film to maintain a certain light transmittance in the visible light range.

[0013] As an improvement of the present invention, the flexible base layer further comprises a microporous structure, and the microporous structure is evenly distributed on the flexible base layer.

[0014] Based on the above technical features, the flexible substrate layer is made of flexible polymer material to ensure the flexibility of the heating film; As an improvement of the present invention, the thickness of the flexible heating film is between 0.1 mm and 1 mm.

[0015] Based on the above technical features, the thickness of the heating film is between 0.1 mm and 1 mm to maintain its flexibility while providing sufficient heating capacity.

[0016] As an improvement of the present invention, the preheating monitoring step includes real-time monitoring of the temperature of the battery cell components of the lithium battery module; automatically starting the heating system when the temperature is lower than a preset threshold; dynamically adjusting the heating intensity according to the temperature feedback of the battery cell components; and shutting down the heating system after heating the battery cell components to the optimal operating temperature.

[0017] Based on the above technical features, voltage sensors are installed on the positive and negative electrodes of each battery cell in the lithium battery module to monitor the battery cell voltage; current sensors are installed at the input and output ends of the battery module to measure the charging and discharging current; temperature sensors are installed at key positions of the battery module to detect the temperature distribution of the module. When voltage, current or temperature abnormalities are detected, the safety protection module is immediately activated to cut off the circuit.

[0018] As an improvement of the present invention, the preheating monitoring step further includes: Monitor the ambient temperature and start the module's thermal management system for preheating when the temperature is lower than the preset threshold of the optimal operating temperature of the battery cell assembly; During the preheating process, the battery management system monitors the temperature of the battery cell assembly in real time and dynamically adjusts the working state of the heating element according to the preset temperature curve until the battery cell assembly reaches the optimal working temperature; During the preheating process, the battery management system records the temperature change data of the battery cell components and optimizes the subsequent preheating procedures based on the data; After preheating is completed, the battery management system automatically switches to normal working mode, manages the charging and discharging process of the battery components, and monitors the status of the battery components.

[0019] Compared with the prior art, the beneficial effects of the present invention are: the device has a rapid preheating response to improve battery performance in low-temperature environments; the optimized arrangement of battery cell components maximizes heat transfer efficiency; the battery management system (BMS) has a preset preheating program to automatically control the heating elements. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the overall structure of the lithium battery module in this embodiment; Figure 2 This is a schematic diagram of the structure of the flexible heating film in this embodiment; Figure 3 This is a preheating monitoring flow chart in this embodiment.

[0021] List of figure symbols: 100 - battery cell assembly, 101 - thermal management device, 102 - heating assembly, 103 - sensing device, 104 - protective layer, 105 - insulating layer, 106 - conductive layer, 107 - flexible substrate layer. DETAILED DESCRIPTION

[0022] The present invention will be further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0023] Example: Figure 1-3As shown, a low-temperature lithium battery module with improved preheating efficiency, the battery module includes a battery cell assembly 100 and a built-in thermal management device 101, the thermal management device 101 includes at least one heating component 102 and a sensor device 103, the module also includes a battery management system for controlling the working state of the heating element and monitoring the charge and discharge state of the battery module, the heating component 102 is arranged between adjacent battery cell assemblies 100, and the sensor device 103 is arranged inside or outside the surface of each battery cell assembly 100. The battery cell assembly 100 forms a predetermined voltage and capacity by series and parallel connection, the module has a built-in thermal management system for quickly preheating the battery cell assembly 100 in a low temperature environment, the heating component 102 is arranged at a position adjacent to the battery cell assembly 100, and is used to directly heat the battery cell assembly 100, and the temperature sensor is arranged on the surface or inside of each battery cell assembly 100, and is used to monitor the temperature of the battery cell assembly 100 in real time. The temperature sensor is an NTC thermistor, which is disposed on the surface or inside of each battery cell assembly 100 and is used to monitor and feedback the temperature of the battery cell assembly 100 in real time.

[0024] Furthermore, the heating element is a flexible heating film, which can fit the shape of the battery cell assembly 100, and the flexible heating film is arranged between the battery cell assemblies 100 and applied on the battery cell assemblies 100 to achieve uniform heating.

[0025] Furthermore, the flexible heating film is a filament-like or strip-like structure, forming a plurality of flexible heating films with filament-like or strip-like structures that are evenly distributed.

[0026] Furthermore, the flexible heating film includes a flexible base layer 107, a conductive layer 106, an insulating layer 105 and a protective layer 104, wherein the conductive layer 106 is disposed on the insulating layer 105, and the protective layer 104 covers the conductive layer 106, wherein the conductive layer 106 is composed of metal, carbon-based material or a mixture thereof, and the conductive layer 106 is a serpentine or spiral structure. The conductive layer 106 is disposed on the insulating layer 105 to generate heat when power is supplied; the protective layer 104 covers the conductive layer 106 to improve the durability and protection of the heating film; the conductive layer 106 adopts a serpentine or spiral layout to improve the heating efficiency; the protective layer 104 adopts a wear-resistant material to enhance the mechanical strength of the heating film.

[0027] Furthermore, the insulating layer 105 is composed of a multi-layer structure, including a bottom insulating film and a top insulating film covering the conductive layer 106 .

[0028] Furthermore, the protective layer 104 includes a transparent protective film, which allows the heating film to maintain a certain light transmittance in the visible light range.

[0029] Furthermore, the flexible substrate layer 107 further comprises a microporous structure, and the microporous structure is evenly distributed on the flexible substrate layer 107. The flexible substrate layer 107 is made of a flexible polymer material to ensure the flexibility of the heating film.

[0030] Further, the thickness of the flexible heating film is between 0.1 mm and 1 mm. The thickness of the heating film is between 0.1 mm and 1 mm to maintain its flexibility while providing sufficient heating capacity.

[0031] Furthermore, the preheating monitoring step includes real-time monitoring of the temperature of the cell assembly 100 of the lithium battery module; automatically starting the heating system when the temperature is lower than a preset threshold; dynamically adjusting the heating intensity according to the temperature feedback of the cell assembly 100; and shutting down the heating system after heating the cell assembly 100 to the optimal working temperature. Voltage sensors are installed on the positive and negative electrodes of each cell in the lithium battery module to monitor the cell voltage; current sensors are installed at the input and output ends of the battery module to measure the charge and discharge current; temperature sensors are installed at key positions of the battery module to detect the temperature distribution of the module. When abnormal voltage, current or temperature is detected, the safety protection module is immediately activated to cut off the circuit.

[0032] Furthermore, the preheating monitoring step further includes: Monitor the ambient temperature, and when the temperature is lower than a preset threshold of the optimal operating temperature of the battery cell assembly 100, start the thermal management system of the module for preheating; During the preheating process, the battery management system monitors the temperature of the battery cell assembly 100 in real time, and dynamically adjusts the working state of the heating element according to a preset temperature curve until the battery cell assembly 100 reaches the optimal working temperature; During the preheating process, the battery management system records the temperature change data of the battery cell assembly 100 and optimizes the subsequent preheating program according to the data; After preheating is completed, the battery management system automatically switches to a normal working mode, manages the charging and discharging process of the battery cell assembly 100 , and monitors the status of the battery cell assembly 100 .

[0033] It should be noted that the above content only illustrates the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications all fall within the protection scope of the claims of the present invention.

Claims

1. A low-temperature lithium battery module with improved preheating efficiency, characterized in that: The battery module comprises a battery cell assembly (100) and a built-in thermal management device (101), wherein the thermal management device (101) comprises at least one heating assembly (102) and a sensor device (103), and the module further comprises a battery management system for controlling the working state of the heating element and monitoring the charge and discharge state of the battery module, wherein the heating assembly (102) is arranged between adjacent battery cell assemblies (100), and the sensor device (103) is arranged inside or on the outer surface of each battery cell assembly (100).

2. A low-temperature lithium battery module with improved preheating efficiency according to claim 1, characterized in that: The heating element is a flexible heating film.

3. A low-temperature lithium battery module with improved preheating efficiency according to claim 2, characterized in that: The flexible heating film is a filament-like or strip-like structure, and a plurality of flexible heating films with filament-like or strip-like structures are evenly distributed.

4. A low-temperature lithium battery module with improved preheating efficiency according to claim 2, characterized in that: The flexible heating film comprises a flexible base layer (107), a conductive layer (106), an insulating layer (105) and a protective layer (104); the conductive layer (106) is arranged on the insulating layer (105); the protective layer (104) covers the conductive layer (106); the conductive layer (106) is composed of metal, carbon-based material or a mixture thereof; and the conductive layer (106) is a serpentine or spiral structure.

5. A low-temperature lithium battery module with improved preheating efficiency according to claim 4, characterized in that: The insulating layer (105) is composed of a multi-layer structure, including a bottom insulating film and a top insulating film covering the conductive layer (106).

6. A low-temperature lithium battery module with improved preheating efficiency according to claim 4, characterized in that: The protective layer (104) comprises a transparent protective film, which allows the heating film to maintain a certain light transmittance in the visible light range.

7. A low-temperature lithium battery module with improved preheating efficiency according to claim 4, characterized in that: The flexible base layer (107) further comprises a microporous structure, and the microporous structure is evenly distributed on the flexible base layer (107).

8. A low-temperature lithium battery module with improved preheating efficiency according to claim 2, characterized in that: The thickness of the flexible heating film is between 0.1 mm and 1 mm.

9. A low-temperature lithium battery module with improved preheating efficiency according to claim 1, characterized in that: The preheating monitoring step comprises real-time monitoring of the temperature of the battery cell assembly (100) of the lithium battery module; automatically starting a heating system when the temperature is lower than a preset threshold; dynamically adjusting the heating intensity according to temperature feedback of the battery cell assembly (100); and shutting down the heating system after heating the battery cell assembly (100) to an optimal operating temperature.

10. A low-temperature lithium battery module with improved preheating efficiency according to claim 9, characterized in that: The preheating monitoring step also includes: Monitoring the ambient temperature, and when the temperature is lower than a preset threshold value of the optimal operating temperature of the battery cell assembly (100), starting the thermal management system of the module for preheating; During the preheating process, the battery management system monitors the temperature of the battery cell assembly (100) in real time, and dynamically adjusts the working state of the heating element according to a preset temperature curve until the battery cell assembly (100) reaches an optimal working temperature; During the preheating process, the battery management system records the temperature change data of the battery cell assembly (100) and optimizes the subsequent preheating program based on the data; After preheating is completed, the battery management system automatically switches to a normal working mode, manages the charging and discharging process of the battery cell assembly (100), and monitors the state of the battery cell assembly (100).

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