A temperature equalization control device for a power battery and a control method thereof

Abstract

The application provides a temperature equalization control device of a power battery and a control method thereof, and belongs to the technical field of battery thermal management. The power battery comprises a plurality of battery cells. First heat-conducting plates are arranged between every two battery cells in the plurality of battery cells. The electrodes of every two battery cells are connected through metal connecting pieces. The temperature equalization control device comprises a liquid cooling plate, a thermoelectric module and a second heat-conducting plate. A plurality of thermoelectric modules are arranged between the first end face and the second end face of the thermoelectric module. The first end face and the second end face constitute the hot end face and the cold end face of the thermoelectric module. The third end face of the second heat-conducting plate is attached to the cold end face, the fourth end face is attached to the metal connecting piece, the second heat-conducting plate is attached to the first heat-conducting plate, and a phase change medium is arranged between the metal connecting piece and the second heat-conducting plate. In this way, the control of different battery cells in the power battery can be realized by controlling the temperature adjustment of the thermoelectric module, and the efficiency of temperature equalization control is improved.

Description

Technical Field

[0001] This application relates to the field of battery thermal management technology, and in particular to a temperature equalization control device and control method for a power battery. Background Technology

[0002] Lithium-ion batteries are widely used in energy storage and power applications. While their fast charging and discharging characteristics meet electrical energy demands, they also generate a significant amount of heat during the process. When the battery temperature exceeds the normal operating temperature range (0°C), the battery becomes hot. At 40℃, both the reduced discharge efficiency and lifespan caused by high temperatures, and the reduced charging and discharging efficiency and accelerated capacity degradation caused by low temperatures, severely impact battery performance and lifespan. Currently, common heat dissipation methods such as air cooling, liquid cooling, composite phase change material homogenization, and phase change cooling can reduce battery temperature to some extent, but they have limitations in battery thermal management under low-temperature environments and cannot effectively solve the many problems caused by low temperatures. Thermoelectric cooling technology, based on the Peltier cooling and heating effects of semiconductors, achieves thermal exchange by changing the input current of the thermoelectric chip, and can cope with battery thermal management in a wide temperature range. However, existing thermoelectric cooling technologies have slow response speeds and poor temperature homogenization performance.

[0003] Therefore, improving the temperature control efficiency of power batteries is an urgent problem to be solved. Summary of the Invention

[0004] This application provides a temperature equalization control device and method for a power battery, which enables precise adjustment of the temperature of different cells in the power battery, thereby improving the temperature equalization control efficiency.

[0005] In a first aspect, this application provides a temperature equalization control device for a power battery, wherein the power battery includes multiple cells, a first heat-conducting plate is disposed between each pair of cells, and the electrodes of each pair of cells are connected by a metal connecting piece, and the temperature equalization control device includes: A thermoelectric module includes a plurality of thermoelectric modules disposed between a first end face and a second end face; the first end face and the second end face are disposed opposite to each other. A liquid cooling plate is disposed at a preset mounting position on the first end face; The second heat-conducting plate includes a third end face and a fourth end face. The third end face is attached to the second end face, and the fourth end face is attached to the metal connecting piece. The second heat-conducting plate is also attached to the first heat-conducting plate. A phase change medium is disposed between the metal connecting piece and the second heat-conducting plate. The third end face and the fourth end face are disposed opposite to each other.

[0006] Furthermore, each of the plurality of thermoelectric modules includes a first electrode and a second electrode; the first electrode and the second electrode are respectively connected to the control drive circuit of the temperature equalization control device; the control drive circuit is used to adjust a preset current parameter of the drive current applied between the first electrode and the second electrode; the current parameter includes current magnitude and current direction; The thermoelectric module adjusts the temperature type of the first end face and the second end face according to the current direction to achieve switching between cold and hot end faces; and adjusts the first temperature and the second temperature corresponding to the first end face and the second end face according to the current magnitude; and determines the heat conduction parameters of the first end face and the second end face according to the first temperature and the second temperature, so that the thermoelectric module selectively absorbs or releases heat on the area corresponding to the second heat-conducting plate and / or the metal connecting piece.

[0007] Furthermore, a thermally conductive buffer layer is provided between the first end face and the liquid cooling plate. The thermally conductive buffer layer is a thermoelastic material with a preset thermal conductivity. The thermally conductive buffer layer is used to provide a heat conduction path between the thermoelectric module and the liquid cooling plate, and to absorb the mechanical impact generated when the liquid cooling plate moves. The first end face of the thermoelectric module is fixed to the liquid cooling plate by welding.

[0008] Furthermore, the thermoelectric module is arranged along the height direction of the power battery; the power battery includes multiple thermoelectric modules; at least one of the multiple thermoelectric modules is arranged in the upper region of the power battery, and / or at least one thermoelectric module is arranged in the lower region of the power battery.

[0009] Furthermore, the multiple thermoelectric modules of the thermoelectric module are arranged along the arrangement direction of the cells in the power battery, and the first region where the cells are located is correspondingly arranged with the second region of the multiple thermoelectric modules, so as to achieve heat regulation of the first region.

[0010] Furthermore, the liquid cooling plate has a liquid inlet and a liquid outlet; a thermally conductive silicone layer is provided between the liquid cooling plate and the first end face, the thermally conductive silicone layer is attached between the liquid cooling plate and the first end face, for transferring heat from the first end face to the liquid cooling plate, and providing buffer protection between the liquid cooling plate and the first end face.

[0011] Furthermore, the metal connecting piece includes a bent portion and two flattened portions, the bent portion protruding away from the battery cell electrode relative to the flattened portion of the metal connecting piece; the two flattened portions are respectively fixedly connected to the battery cell electrode by laser welding.

[0012] Furthermore, the adjacent metal connecting pieces together with the second heat-conducting plate form a second space, the phase change medium is disposed in the second space and is attached to the second heat-conducting plate; the phase change medium is an insulating and buffering material used to absorb mechanical vibrations between the multiple battery cells.

[0013] Secondly, this application provides a method for controlling the uniform temperature of a power battery, applied to a control drive board in a uniform temperature control device. The uniform temperature control device includes a thermoelectric module, which includes multiple thermoelectric modules. The control drive board is connected to the thermoelectric module. The method includes: The system monitors multiple first temperature values ​​of multiple cells in the power battery and multiple first voltage values ​​of multiple thermoelectric modules corresponding to the multiple cells within a preset time period in real time. Each voltage value corresponds one-to-one with each first temperature value. The system determines the average temperature of the multiple first temperature values. The system determines the difference between each first temperature value and the average temperature value to obtain multiple temperature difference values. When the target temperature difference value is greater than a preset first threshold, the system determines the adjustment voltage value corresponding to the target temperature difference value according to a preset mapping relationship between the temperature difference value and the adjustment voltage value to obtain a target voltage adjustment value. The target temperature difference value is any one of the multiple temperature difference values. The system determines the target first voltage value corresponding to the target voltage adjustment value from the multiple first voltage values. The system adjusts the voltage of the target thermoelectric module corresponding to the target voltage adjustment value according to the target first voltage value to obtain a second voltage value. The system performs heat control on the target thermoelectric module according to the second voltage value.

[0014] Thirdly, this application provides a temperature equalization control system for a power battery, wherein the temperature equalization control system for the power battery includes the apparatus described in the first aspect of the embodiments of this application.

[0015] Fourthly, this application provides a temperature equalization control device for a power battery, including a processor, a memory, a communication interface, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the processor, and the programs include instructions for performing the steps in the method of the second aspect of the embodiments of this application.

[0016] Fifthly, this application provides a computer program product, wherein the computer program product includes a non-transitory computer-readable storage medium storing a computer program operable to cause a computer to perform some or all of the steps described in the method of the second aspect of the embodiments of this application. The computer program product may be a software installation package.

[0017] This application describes a power battery temperature equalization control device and control method. The power battery includes multiple cells, with a first heat-conducting plate disposed between each pair of cells, and the electrodes of each pair of cells connected by a metal connecting piece. The temperature equalization control device includes a liquid cooling plate, a thermoelectric module, and a second heat-conducting plate. The thermoelectric module includes a first end face and a second end face, and multiple thermoelectric modules disposed on the first end face and the second end face. The first end face and the second end face are disposed opposite to each other. The third end face of the second heat-conducting plate is attached to the second end face, and the fourth end face is attached to the metal connecting piece. The second heat-conducting plate is also attached to the first heat-conducting plate. A phase change medium is disposed between the metal connecting piece and the second heat-conducting plate. Thus, on the one hand, by configuring multiple sets of temperature equalization control devices in the power battery pack, the cold end of the thermoelectric module of the temperature equalization control device is bonded to the cell electrode through insulating thermally conductive silicon, while the hot end is fixed to the metal surface of the liquid cooling plate through thermally conductive silicone, ensuring efficient heat transfer and thus improving the heat dissipation capacity of the power battery. When the external temperature is low, by changing the direction of the drive current, the cold and hot ends of the thermoelectric module are interchanged, and the thermoelectric module can switch to heating mode to achieve preheating of the power battery. On the other hand, the power battery uses multiple thermoelectric modules to deliver current independently or in groups. According to the temperature difference between different cells, the current of the thermoelectric module of the corresponding battery cell is adjusted to finely control the temperature of each cell, thereby improving the response speed of TEC and improving the efficiency of temperature equalization control. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of a thermal management system for a power battery provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of a temperature equalization control device provided in an embodiment of this application; Figure 3 This is a schematic diagram of the structure of a thermoelectric module provided in an embodiment of this application; Figure 4 This is a schematic diagram of the structure of a thermoelectric module provided in an embodiment of this application; Figure 5 This is a schematic diagram of a thermoelectric module connection structure provided in an embodiment of this application; Figure 6 This is a schematic diagram of a power battery cell connection provided in an embodiment of this application; Figure 7This is a schematic diagram of the installation structure of a power battery provided in an embodiment of this application; Figure 8 This is a schematic flowchart of a method for controlling the uniform temperature of a power battery according to an embodiment of this application; Figure 9 This is a schematic diagram of the structure of a power battery temperature equalization control device provided in an embodiment of this application. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present application.

[0021] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0022] It should be understood that the term "and / or" in this document 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 existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document indicates that the preceding and following related objects are in an "or" relationship. In the embodiments of this application, "multiple" refers to two or more.

[0023] In the embodiments of this application, "at least one item" or its similar expression refers to any combination of these items, including any combination of a single item or a plurality of items. "One or more" means one or more, while "multiple" means two or more. For example, "at least one item" of a, b, or c can represent the following seven cases: a, b, c; a and b; a and c; b and c; a, b, and c. Each of a, b, and c can be an element or a set containing one or more elements.

[0024] In this application, the term "connection" refers to various connection methods, such as direct connection or indirect connection, to achieve communication between devices. This application does not impose any limitations on this.

[0025] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0026] The relevant terms used in the embodiments of this application will be explained below: Thermoelectric cooling technology: Thermoelectric cooling (TEC), also known as semiconductor refrigeration / heating technology, is a technology that converts electrical energy into heat energy based on the Peltier effect of semiconductors.

[0027] During high-temperature charging and discharging, lithium-ion battery packs reduce their output capacity to ensure safety, potentially affecting battery performance and lifespan. Existing battery temperature control methods primarily include air cooling, liquid cooling, phase change material (PCM) cooling, and composite PCM temperature equalization. However, these methods mainly focus on heat dissipation and lack solutions for low-temperature battery temperature management. Furthermore, existing temperature control methods are suitable for wide temperature ranges, but the temperatures of multiple lithium-ion cells within a battery pack may differ, resulting in a lack of precise cell-level control. Consequently, existing thermoelectric cooling (TEC) technologies exhibit slow response times and poor temperature equalization performance.

[0028] To address the aforementioned problems, this application provides a temperature equalization control device and method for a power battery. The power battery includes multiple cells, with a first heat-conducting plate positioned between each pair of cells. The electrodes of each pair of cells are connected by a metal connecting piece. The temperature equalization control device includes a liquid cooling plate, a thermoelectric module, and a second heat-conducting plate. The thermoelectric module includes multiple thermoelectric modules disposed between a first end face and a second end face. The third end face of the second heat-conducting plate is attached to the first end face, and the fourth end face is attached to the metal connecting piece. The second heat-conducting plate is also attached to the first heat-conducting plate. A phase change medium is disposed between the metal connecting piece and the second heat-conducting plate. This method enables control of different cells within the power battery, thereby improving the efficiency of temperature equalization control.

[0029] The following is combined Figure 1 The structure of a thermal management system for a power battery according to an embodiment of this application will be described. Figure 1This is a schematic diagram of the structure of a thermal management system for a power battery provided in an embodiment of this application. The thermal management system for the power battery includes: a liquid cooling plate 101, a heat insulation material 102, an insulating heat-conducting plate 103, a phase change material 104, a lithium battery cell 105, a heat-conducting plate 106, a metal connecting piece 107, and thermoelectric modules 108, wherein 7 or 8 thermoelectric modules 108 constitute a thermoelectric module. Figure 1 (Not marked in the text).

[0030] The thermal management system of the power battery includes three temperature equalization control devices. Two of these devices are located on top of the lithium battery and arranged in parallel, while one device is located at the bottom. In one possible embodiment, the power battery includes multiple battery cells (lithium battery cells 105). A first heat-conducting plate (heat-conducting plate 106) is disposed between each pair of cells, and the electrodes of each pair of cells are connected by a metal connecting piece (metal connecting piece 107). The temperature equalization control device includes: Thermoelectric module includes a plurality of thermoelectric modules (thermoelectric module 108) disposed between a first end face and a second end face, wherein the first end face and the second end face are disposed opposite to each other. Liquid cooling plate 101 is disposed at a preset mounting position on the hot end face; The second heat-conducting plate (insulating heat-conducting plate 103) includes a third end face and a fourth end face. The third end face is attached to the cold end face, and the fourth end face is attached to the metal connecting piece. The second heat-conducting plate is attached to the first heat-conducting plate. A phase change medium (phase change material 104) is disposed between the metal connecting piece and the second heat-conducting plate. The third end face and the fourth end face are disposed opposite to each other.

[0031] In this system, a first heat-conducting plate (heat-conducting plate 106) is embedded between two battery cells. Its high thermal conductivity allows for the transfer of chemical heat from the battery cells to the liquid cooling plate 101, suppressing the formation of localized hot spots. The electrodes of the two battery cells are electrically connected via metal connecting pieces 107, which also generate heat (electrode heat). The phase change material 104, based on the characteristics of metal phase change, absorbs the electrode heat from the metal connecting pieces 107 and transfers the temperature to the insulating heat-conducting plate 103 for heat dissipation through the liquid cooling plate 101. The core of the temperature control device is a thermoelectric module, composed of multiple thermoelectric modules 108. Each thermoelectric module includes interconnected first and second substrates, and a thermoelectric structure (such as a semiconductor cooling / heating unit) sandwiched between the two substrates. The multiple first substrates together form the cold end face of the thermoelectric module, while the multiple second substrates form the hot end face. Through the thermoelectric effect, the heat can be directionally transferred between the cold and hot ends, providing active temperature control capabilities.

[0032] The liquid cooling plate 101 is positioned at a pre-installed location on the hot end face of the thermoelectric module. A cooling medium flows within it, rapidly removing heat from the hot end face and preventing heat buildup that could reduce thermoelectric conversion efficiency. The close fit between the liquid cooling plate 101 and the hot end face minimizes contact thermal resistance at the heat exchange interface, improving heat dissipation rate. Furthermore, the liquid cooling plate 101 is surrounded by a thermal insulation material 102 to collect heat from the hot end face for dissipation through the liquid cooling plate 101, thereby improving heat dissipation efficiency. The third end face of the second heat-conducting plate (insulating heat-conducting plate 103) is tightly fitted to the cold end face of the thermoelectric module, achieving efficient heat / cold transfer. The fourth end face is simultaneously fitted to the metal connecting piece 107 and the heat-conducting plate 106 for better temperature control. Between the metal connecting piece 107 and the insulating heat-conducting plate 103, a phase change material 104 is also filled. This material can absorb or release heat through latent heat of phase change when the cell temperature fluctuates, further smoothing temperature changes and enhancing thermal buffering capacity. The heat insulation material 102 is disposed in the edge area between the liquid cooling plate 101 and the insulating heat-conducting plate 103, which can block unnecessary heat exchange between the liquid cooling plate and the cell module, ensuring that the temperature control energy is concentrated on the target area. The number of thermoelectric modules 108 (7 to 8) is selected to match the heat load characteristics of the cell module, and the adjustment range of temperature control power is improved by connecting multiple modules in parallel. When the cell is under high load heat release, the thermoelectric module starts the cooling mode. The cold end face transfers the cold energy to the cell and metal connecting piece through the insulating heat-conducting plate 103, while the phase change material 104 absorbs excess heat. When the cell temperature is too low, the thermoelectric module switches to the heating mode. The heat from the hot end face is transferred back to the cell through the cold end face, realizing preheating start-up in low temperature environment.

[0033] It is evident that through active thermoelectric regulation, phase change thermal storage buffer, and multi-stage heat conduction design, temperature control of the power battery under various operating conditions is achieved, effectively suppressing temperature differences between cells. Furthermore, the coupling of liquid cooling and thermoelectric modules improves temperature control efficiency. At the same time, the electrical insulation and thermal directional conduction characteristics of the combination of insulating heat-conducting plates and heat-insulating materials ensure the safety and energy utilization efficiency of the power battery. The introduction of phase change materials further enhances the adaptability to load fluctuations, thereby improving the cycle life and operational stability of the power battery.

[0034] Furthermore, for ease of understanding, please refer to Figure 2 , Figure 2This is a schematic diagram of a temperature equalization control device provided in an embodiment of this application. As can be seen, the temperature equalization control device 200 mainly consists of a thermoelectric module 108, a liquid cooling plate 101, etc. Among them, the battery cell 203 is the energy storage unit of the power battery, which adopts a multi-cell series arrangement. Adjacent cells are electrically connected to the electrodes on the cells through metal connecting pieces. The chemical heat generated during its operation and the Joule heat of the electrical connection parts together constitute the temperature control object. The thermoelectric module 108 is the core execution unit of active temperature control. Based on the semiconductor Peltier effect, it realizes the switching between cooling and heating modes by switching the current direction, adapting to the wide temperature range operating conditions. The liquid cooling plate 101 is the heat export terminal. Through the circulation of the internal cooling medium, the heat transferred by the thermoelectric module is quickly transferred to the outside of the module.

[0035] Specifically, the cold end of the thermoelectric module 108 is tightly bonded to the electrode connection of the battery cell 203 via insulating thermally conductive silicone, allowing heat generated by the battery cell and its connection to be efficiently conducted to the cold end of the thermoelectric module. The hot end of the thermoelectric module 108 is fixed to the metal surface of the liquid cooling plate 101 via a thermally conductive silicone layer. This thermally conductive silicone layer serves both as a buffer and a heat conductor, mitigating mechanical damage to the thermoelectric module from vibration and impact, while ensuring that heat from the hot end is transferred to the liquid cooling plate without loss. Based on the heat generation characteristics of the battery cell module, each lithium battery module with a capacity of at least 2 kWh is equipped with two of these temperature equalization control devices. Each device contains 8-9 thermoelectric modules, forming a multi-node array layout to achieve precise temperature control of different areas of the battery cell module. This solves the problem of insufficient adaptability of traditional heat dissipation methods to low-temperature environments, and further improves temperature equalization performance and response speed through the array layout and independent control strategy of the thermoelectric modules. The optimized heat conduction path is achieved by bonding the thermoelectric module with the battery cell and liquid cooling plate. Combined with the improved mechanical properties and consistency of the thermoelectric module through powder metallurgy, this ensures the long-term stable operation of the temperature control system and provides a reliable guarantee for the temperature balance of the power battery under complex operating conditions such as fast charging and discharging and extreme temperature environments.

[0036] In one possible embodiment, each of the plurality of thermoelectric modules includes a first electrode and a second electrode; the first electrode and the second electrode are respectively connected to the control drive circuit of the temperature equalization control device; the control drive circuit is used to adjust a preset current parameter of the drive current applied between the first electrode and the second electrode; the current parameter includes current magnitude and current direction; The thermoelectric module adjusts the temperature type of the first end face and the second end face according to the current direction to achieve switching between cold and hot end faces; and adjusts the first temperature and the second temperature corresponding to the first end face and the second end face according to the current magnitude; and determines the heat conduction parameters of the first end face and the second end face according to the first temperature and the second temperature, so that the thermoelectric module selectively absorbs or releases heat on the area corresponding to the second heat-conducting plate and / or the metal connecting piece.

[0037] The first and second substrates are preferably made of alumina ceramic or aluminum nitride ceramic materials to ensure electrical isolation between the electrodes and the PN junction and reduce interfacial thermal resistance. The first and second electrodes are integrated onto the surface of the first substrate using a copper or silver conductive layer through a thick-film printing process. The electrode layout matches the PN junction array to achieve uniform current distribution and low-loss transmission. The PN junction is composed of alternating N-type and P-type bismuth telluride-based semiconductor materials, forming an electrically series and thermally parallel structure with the upper and lower substrates through metallized connection points. The number of PN junctions is set to dozens to hundreds of pairs according to the power requirements of the thermoelectric module to ensure that the heat conduction efficiency meets the temperature control requirements of the power battery. The thermoelectric module is connected to the driving current through the first and second electrodes. The direction of the current controls the direction of heat conduction, and the magnitude of the current controls the heat conduction power to achieve heating or cooling of the battery cell.

[0038] Specifically, the control drive circuit switches between the cooling and heating modes of the thermoelectric module by adjusting the direction of the drive current applied between the first and second electrodes. When the drive current is in the first direction, the PN junction drives heat to migrate directionally from the second substrate to the first substrate through the Peltier effect, making the first substrate the cold end. The heat is absorbed by the metal connecting piece and the battery cell tab area through the second heat-conducting plate, achieving active cooling. When the drive current is switched to the second direction, the heat is driven to migrate from the first substrate to the second substrate, making the second substrate the hot end. The heat is transferred to the battery cell through the second heat-conducting plate, achieving active preheating. Simultaneously, the control drive circuit controls the temperature difference between the first and second substrates by adjusting the magnitude of the drive current, thereby adjusting the heat conduction parameters of the thermoelectric module on the second heat-conducting plate and / or the corresponding area of ​​the metal connecting piece. This allows for differentiated heat control based on the temperature differences of different battery cells, improving the accuracy and response speed of temperature uniformity control.

[0039] For easier understanding, please refer to Figure 3 , Figure 3This is a schematic diagram of a thermoelectric module provided in an embodiment of this application. As can be seen, the thermoelectric module 108 adopts a stacked integrated structure, consisting of a first substrate 301, a second substrate 302, a thermoelectric structure 303, a first electrode 304, and a second electrode 305. Reversible conversion between heat absorption and heat generation modes is achieved by switching the direction of the electrode current, adapting to the bidirectional requirements of power battery temperature control. The first substrate 301 and the second substrate 302 serve as supporting and insulating carriers, ensuring the stability and electrical isolation of the thermoelectric structure. The thermoelectric structure 303 achieves the mutual conversion of electrothermal energy through a PN junction array. The first electrode 304 and the second electrode 305 serve as current input ports, switching polarity according to operating conditions.

[0040] Specifically, the first substrate 301 and the second substrate 302 are made of high thermal conductivity aluminum nitride ceramic material, which can efficiently transfer heat and protect the internal structure. The thermoelectric structure 303 consists of multiple sets of alternately arranged N-type and P-type semiconductor thermoelectric arms. The two ends of the thermoelectric arms are connected to the upper and lower substrates through metallized connection layers to form a series PN junction array. The number and size of the arms are precisely designed according to the temperature control power requirements. The first electrode 304 and the second electrode 305 are made of high conductivity copper material and are integrated on the edge of the second substrate 302 through thick film printing process. The pin layout is adapted to the wiring requirements of the external control circuit. When the first electrode 304 is the positive electrode and the second electrode 305 is the negative electrode, the PN junction exhibits the Peltier effect. The first substrate 301 side absorbs heat to form a cold end, and the second substrate 302 side releases heat to form a hot end. When the electrode polarity is switched so that the second electrode 305 is the positive electrode and the first electrode 304 is the negative electrode, the heat transfer direction is reversed. The first substrate 301 side releases heat to form a hot end, and the second substrate 302 side absorbs heat to form a cold end. It can be seen that the thermoelectric module 108 achieves the switching between heat absorption and heat generation functions by changing the polarity of the first electrode 304 and the second electrode 305, so as to adapt to the temperature control requirements of high temperature heat dissipation and low temperature preheating of the power battery.

[0041] In one possible embodiment, a thermally conductive buffer layer is provided between the first end face and the liquid cooling plate. The thermally conductive buffer layer is a thermoelastic material with a preset thermal conductivity. The thermally conductive buffer layer is used to provide a heat conduction path between the thermoelectric module and the liquid cooling plate, and to absorb the mechanical impact generated when the liquid cooling plate moves. The first end face of the thermoelectric module is fixed to the liquid cooling plate by welding.

[0042] The thermally conductive buffer layer is made of a high thermal conductivity pad material with a preset thermal conductivity coefficient, such as a silicone pad with added thermally conductive filler, whose thermal conductivity is not less than [a certain value]. This system combines efficient heat conduction with elastic buffering. The thermally conductive buffer layer is tightly bonded between the first end face and the liquid cooling plate, forming a low-thermal-resistance heat conduction path. This efficiently transfers heat generated at the hot end of the thermoelectric module to the liquid cooling plate. Simultaneously, utilizing its thermoelastic material deformation capability, it absorbs the relative movement of the power battery caused by vibration, impact, or thermal expansion differences during operation, providing stress buffering protection for the thermoelectric module and preventing chip damage caused by rigid connections. Preferably, the first end face of the thermoelectric module can also be directly welded to the end face of the liquid cooling plate for a more robust physical connection. Welding completely eliminates microscopic gaps between the contact interfaces, further reducing contact thermal resistance and minimizing the risk of relative movement and impact between components.

[0043] Specifically, during assembly, the thermally conductive buffer layer is first laid flat on the mounting surface of the liquid cooling plate. Then, the first end face of the thermoelectric module is pressed onto the thermally conductive buffer layer. Pre-set fasteners apply uniform pre-tightening force, causing the thermally conductive buffer layer to undergo slight elastic deformation, completely filling all interface gaps. If direct welding is used, reflow soldering or laser welding processes are used to form a metallurgical bond between the metallized area of ​​the first end face and the surface of the liquid cooling plate, eliminating the need for the thermally conductive buffer layer. The welded layer then simultaneously undertakes the functions of heat conduction and mechanical fixation. When the thermoelectric module is in cooling mode, heat is transferred from the battery cell to the cold end of the thermoelectric module via the second heat-conducting plate. Through the thermoelectric effect, it is pumped to the first end face and then conducted to the liquid cooling plate via the thermally conductive buffer layer or the welded interface, where it is carried away by the cooling medium. When the thermoelectric module switches to heating mode, the heat transfer path is reversed. The liquid cooling plate acts as a uniform heat source, providing initial heat to the thermoelectric module through the first end face, assisting in rapid preheating. The elastic buffering properties of the thermally conductive buffer layer can effectively absorb fatigue stress caused by long-term thermal cycling and vibration, while welding fixation provides a connection option with lower thermal resistance in scenarios with compact space and controllable vibration levels. This ensures stable operation of the temperature control device throughout its entire lifespan.

[0044] In one possible embodiment, the thermoelectric module is disposed along the height direction of the power battery; the power battery includes a plurality of thermoelectric modules; at least one of the plurality of thermoelectric modules is disposed in the upper region of the power battery, and / or, at least one of the thermoelectric modules is disposed in the lower region of the power battery.

[0045] Preferably, there are three thermoelectric modules. All three modules are tightly bonded to the metal connecting pieces and heat-conducting plates of the battery cell module via an insulating thermally conductive layer. The upper two modules primarily cover the battery cell tab connection area, which generates additional Joule heat due to interconnection resistance and is the main high-temperature heat source. The lower module corresponds to the lower part of the battery cell body, where the temperature is relatively low but overall temperature uniformity needs to be maintained. During fast charging and discharging, the temperature in the upper region rises rapidly. The two upper thermoelectric modules simultaneously activate cooling mode, quickly absorbing heat through the Peltier effect and transferring it to the liquid cooling plate for discharge. The lower module activates low-to-medium power cooling based on temperature feedback to suppress the widening of the temperature difference between the upper and lower regions. During preheating in low-temperature environments, all three modules collaboratively activate heating mode. The upper module, due to greater heat loss, uses slightly higher power to ensure that the overall temperature of the power battery rises uniformly to the operating threshold, avoiding insufficient local preheating that could affect performance.

[0046] In one possible embodiment, the multiple thermoelectric modules of the thermoelectric module are arranged along the arrangement direction of the cells in the power battery, and the first region where the cells are located is correspondingly arranged with the second region of the multiple thermoelectric modules, so as to achieve heat regulation of the first region.

[0047] The specific number of thermoelectric modules in the thermoelectric module is determined according to the number, arrangement, and heat load distribution characteristics of the battery cells. For example, when the battery uses 16 cells arranged in series, the thermoelectric module can be configured to include 8 or 9 thermoelectric modules, with each module covering the thermal management area of ​​1 to 2 cells. Each thermoelectric module in the thermoelectric module is electrically connected in parallel and independently connected to the control drive circuit to achieve independent adjustment of the start / stop and power of a single module. Multiple thermoelectric modules are arranged along the arrangement direction of the battery cells, and the second area where each thermoelectric module is located matches the first area where the corresponding battery cell is located, ensuring that the temperature control energy of each area can accurately match the actual heat load distribution of the battery cells in that area.

[0048] Specifically, during the charging and discharging process of a power battery, the heat dissipation conditions of the cells in the middle region are poor, and the temperature is usually higher than that of the end regions. Therefore, by dividing the thermoelectric module into multiple independent and controllable thermoelectric modules and establishing a one-to-one or one-to-many correspondence with the cell regions, the control drive circuit can apply differentiated drive voltages to each thermoelectric module according to the actual temperature differences of different cell regions. For example, a larger drive voltage is output to the thermoelectric module corresponding to the higher-temperature middle region to enhance the cooling capacity; a smaller drive voltage is output to the module corresponding to the lower-temperature edge region or the output is stopped to reduce unnecessary energy consumption. This independent control method based on the region correspondence allows the temperature equalization control device to adapt to power battery modules with different numbers and arrangements of cells, rather than being limited to a specific number of cells or modules, thereby significantly improving the applicability and universality of protection.

[0049] For easier understanding, please refer to Figure 4 , Figure 4 This is a schematic diagram of a thermoelectric module provided in an embodiment of this application. As can be seen, the thermoelectric module has two forms: one is thermoelectric module 1, composed of 8 thermoelectric modules and metal connecting pieces; the other is thermoelectric module 2, composed of 9 thermoelectric modules and metal connecting pieces. Both thermoelectric module 1 and thermoelectric module 2 are composed of multiple thermoelectric modules arranged in a linear array, and the thermoelectric modules are correspondingly arranged with the metal connecting pieces of the power battery. The thermoelectric modules are temperature control units, uniformly distributed along the extension direction of the metal connecting pieces; the metal connecting pieces are electrical connections and heat conduction nodes between battery cells, and their heat generation is one of the main local heat sources of the power battery. The module arrangement density of thermoelectric module 1 and thermoelectric module 2 differs to adapt to the heat load characteristics of different regions.

[0050] Specifically, both thermoelectric module 1 and thermoelectric module 2 adopt a linear array structure. The thermoelectric module is a square ceramic encapsulation unit, and adjacent modules are filled with phase change material to ensure continuous heat conduction and temperature control. The thermoelectric module corresponds one-to-one with the metal connecting piece, and its cold end face is directly attached to the surface of the metal connecting piece, so that the Joule heat generated by the connecting piece can be directly transferred to the thermoelectric module, reducing heat conduction path loss.

[0051] In one possible embodiment, the liquid cooling plate has a liquid inlet and a liquid outlet; a thermally conductive silicone layer is disposed on the liquid cooling plate and the hot end face, the thermally conductive silicone layer being attached to the liquid cooling plate and the first end face, for transferring heat from the first end face to the liquid cooling plate, and providing buffer protection between the liquid cooling plate and the first end face.

[0052] The liquid cooling plate is made of aluminum alloy using a one-piece molding process. It features an internal parallel flow channel structure with symmetrically arranged inlet and outlet ports at both ends. Connected to an external cooling circulation system, it achieves continuous flow and efficient heat exchange of the cooling medium. The thermally conductive silicone layer is made of high thermal conductivity (…). The material has low hardness, excellent thermal conductivity and elastic deformation capability, and a thickness of about 0.5-1.5mm. It can completely fill the micro gap between the liquid cooling plate and the hot end face of the thermoelectric module, eliminating the problem of increased thermal resistance caused by the interface air gap.

[0053] Specifically, during assembly, a thermally conductive silicone layer is first uniformly coated onto the bonding surface of the liquid cooling plate or the hot end face of the thermoelectric module (the first end face). Then, the liquid cooling plate and the thermoelectric module are fixed together using fasteners, causing the thermally conductive silicone layer to elastically deform under pressure, forming a gapless, tightly bonded interface. When the thermoelectric module is in cooling mode, the heat generated at the hot end face is rapidly conducted to the liquid cooling plate through the thermally conductive silicone layer, carried away by the internal cooling medium, and discharged through the outlet. When the module switches to heating mode, the thermally conductive silicone layer can also efficiently transfer heat, working in conjunction with the temperature regulation function of the liquid cooling plate to achieve uniform preheating of the battery cell. Furthermore, the elastic properties of the thermally conductive silicone layer can buffer the vibration and impact generated during battery operation, preventing structural damage caused by rigid contact between the liquid cooling plate and the thermoelectric module, while also compensating for assembly errors and differences in thermal expansion, ensuring the long-term stability of the interface bonding.

[0054] In one possible embodiment, the metal connecting piece includes a bent portion and two flattened portions, the bent portion protruding away from the battery cell electrode relative to the flattened portion of the metal connecting piece; the two flattened portions are respectively fixedly connected to the battery cell electrode by laser welding.

[0055] The metal connecting piece is integrally formed from a high-conductivity copper alloy or aluminum-magnesium alloy. The transition area between its bent and flattened sections features a rounded transition design to avoid stress concentration and ensure structural mechanical stability. The protrusion height of the bent section is set according to the assembly space and heat dissipation requirements of the power battery module, controlled within 3-8mm. This protrusion structure provides sufficient contact space for the cold end of the thermoelectric module to be bonded without affecting the cell arrangement density, allowing the thermoelectric module to directly align with the core heat-generating area of ​​the metal connecting piece, reducing intermediate medium loss in the heat conduction path. The two flattened sections are end extensions of the metal connecting piece, with their surfaces polished to ensure flatness and maximize the contact area with the cell electrodes. This improves the reliability of the electrical connection and enhances heat conduction efficiency, ensuring that the Joule heat generated at the tabs can be quickly transferred to the entire connecting piece.

[0056] For easier understanding, please refer to Figure 5 , Figure 5This is a schematic diagram of a thermoelectric module connection structure provided in an embodiment of this application. As can be seen, the thermoelectric module has a metal connecting piece as the bottom layer, with an insulating heat-conducting plate, a thermoelectric module, and the heat-conducting plate stacked sequentially. The metal connecting piece is the electrical connection component between the battery cells; however, since the battery cell tabs generate Joule heat and are also heat sources, heat conduction is required. The insulating heat-conducting plate serves both as electrical isolation and heat conduction. The thermoelectric module is the heat conversion execution unit, and the heat-conducting plate is used to further distribute or conduct heat to the liquid cooling plate.

[0057] Specifically, the metal connecting pieces are made of highly conductive copper alloy, with their bent sections bulging upwards to form a concentrated heat source area. The surface is nickel-plated to improve corrosion resistance and thermal contact performance. The insulating heat-conducting plate is made of aluminum nitride ceramic matrix composite material. One side of the plate is tightly fitted to the bulging area of ​​the metal connecting pieces, while the other side contacts the cold end of the thermoelectric module. This plate both blocks the electrical conduction between the metal connecting pieces and the thermoelectric module and efficiently transfers the Joule heat generated by the connecting pieces to the thermoelectric module through its high thermal conductivity. The hot end of the thermoelectric module is attached to the heat-conducting plate, which is made of aluminum alloy. This further distributes the heat dissipated by the thermoelectric module before transferring it to the liquid cooling system. A phase change material is filled between each metal connecting piece.

[0058] It is evident that the connection design of the various components in the thermoelectric module not only solves the electrical interference problem between the metal connecting plates and the thermoelectric module, but also constructs a short-range, efficient heat conduction path, effectively absorbing the Joule heat from the connecting plates. The cooperation between the insulating heat-conducting plates ensures system safety and improves the uniformity and dissipation of heat, enabling the thermoelectric module to act on the local heat source of the electrical connection node, significantly reducing the temperature difference between the cells, and providing reliable structural support for the efficient thermal management of the power battery module.

[0059] In one possible embodiment, the two adjacent metal connecting pieces and the second heat-conducting plate enclose a second space, the phase change medium is disposed in the second space and is attached to the second heat-conducting plate; the phase change medium is an insulating and buffering material used to absorb mechanical vibrations between the multiple battery cells.

[0060] The metal connecting pieces are manufactured using a one-piece molding process with high-conductivity copper alloy or aluminum-magnesium alloy. The spacing between adjacent connecting pieces is set according to the electrode distribution and heat load density of the battery cell module. The bent portions of these pieces bulge away from the battery cell, forming a closed second space together with the second heat-conducting plate (aluminum nitride ceramic matrix composite material). This second space has a U-shaped or trapezoidal cross-section, with a volume adapted to the required amount of phase change medium, ensuring that the phase change medium completely covers the heat-generating area of ​​the metal connecting pieces. The phase change medium, a composite functional medium with both insulating and buffering properties, is positioned between the metal connecting pieces and the second heat-conducting plate. This phase change medium not only absorbs or releases heat through latent heat of phase change to mitigate temperature fluctuations in the battery cell, but also acts as an elastic buffer filling the structural gaps between adjacent battery cells, absorbing mechanical vibration energy generated during battery operation due to vibration, impact, or the thermal expansion of the battery cell itself.

[0061] Specifically, during the battery module assembly stage, the second heat-conducting plate is first fixed to the preset position of the cell module using insulating thermally conductive adhesive. Then, adjacent metal connecting pieces are connected to the cell tabs using laser welding, forming a sealed second space between the bent portion of the connecting piece and the second heat-conducting plate. Subsequently, a phase change medium (phase change material) is injected into the second space. After the medium cools and solidifies, a solid phase change layer is formed that is tightly bonded to the second heat-conducting plate. When the cell is working, the heat generated by the Joule effect of the metal connecting pieces is first transferred to the phase change medium. When the temperature reaches the phase change threshold, the phase change medium absorbs latent heat and transforms into a liquid state, achieving rapid heat storage and preventing a sudden rise in the local temperature of the connecting pieces. When the cell temperature decreases or the thermoelectric module starts the heating mode, the phase change medium releases the stored latent heat, which is transferred back to the cell through the second heat-conducting plate, helping to maintain the stability of the cell temperature. Furthermore, the phase change medium is selected from elastic phase change materials with high insulation resistivity, such as silicone-based composite phase change materials with added thermally conductive fillers. These materials maintain excellent electrical insulation properties throughout the solid-liquid transition process, effectively isolating the electrical path between the metal connecting piece and the second heat-conducting plate, thus avoiding the risk of short circuits due to dielectric conductivity. Simultaneously, this phase change medium possesses a preset elastic modulus and compressive deformation capacity in its solid state. When the power battery is subjected to external mechanical impact or when internal cells experience expansion and contraction stress due to temperature changes, the phase change medium can absorb vibration energy through its own elastic deformation, reducing rigid collisions and friction between adjacent cells and between cells and metal connecting pieces. This reduces the risk of cell structural damage and improves the vibration resistance, durability, and long-term reliability of the battery module.

[0062] As can be seen, this design achieves the positioning of the phase change medium through the second space enclosed by the metal connecting piece and the second heat-conducting plate. It not only utilizes the latent heat storage characteristics of the phase change medium to smooth the temperature fluctuation of the metal connecting piece, but also constructs an efficient heat conduction path through the close fit between the phase change medium and the second heat-conducting plate, effectively solving the problems of untimely heat dissipation of local hot spots and poor temperature uniformity in traditional thermal management.

[0063] For easier understanding, please refer to Figure 6 , Figure 6 This is a schematic diagram of a power battery cell connection provided in an embodiment of this application. As can be seen, the tabs of adjacent cells are interconnected through metal connecting pieces to form a series cell module. The lithium battery cells are arranged in an array, with the positive and negative tabs of each cell located at both ends of the cell. The metal connecting piece is a strip-shaped conductive component that bridges the positive and negative tabs of adjacent cells, forming an electrical path between the cells. The connection area between the tabs and the metal connecting piece is the electrical contact point and also the main area for the generation of Joule heat.

[0064] Specifically, the lithium battery cell uses a square shell packaging. The positive and negative electrode tabs are made of aluminum and copper, respectively, and their surfaces are nickel-plated to improve corrosion resistance and weldability. The metal connecting piece is made of a high-conductivity copper alloy, with its width matching the tab width and its length covering the tab spacing between adjacent cells. It is fixedly connected to the tab using a laser welding process. The cells are arranged in an alternating positive and negative configuration, and the metal connecting piece sequentially connects the positive tab of the previous cell to the negative tab of the next cell, ultimately forming a continuous series circuit. This allows the total voltage of the cell module to linearly increase with the number of cells.

[0065] It is evident that this connection structure, through the bridging design of the metal connecting pieces, achieves efficient series integration of the cell modules, ensuring the reliability and low loss of the electrical connection. The combination of the array-style cell arrangement and the strip connecting pieces ensures the space utilization and ease of assembly of the thermoelectric module, while also making the heat distribution regular, facilitating the modular design and precise control of the thermal management system, and providing a structural foundation for the synergistic optimization of the electrical and thermal performance of the power battery module.

[0066] For easier understanding, please refer to Figure 7 , Figure 7This is a schematic diagram of the installation structure of a power battery provided in an embodiment of this application. As can be seen, the structure adopts a double-layer parallel arrangement of cell modules, with the outer shell 71 serving as the bottom support and protective carrier. Both the upper and lower layers are equipped with cell units with heat dissipation components, and also integrate electrical components such as cable interfaces, forming a compact and modular power battery assembly architecture. The outer shell 71 serves as the base of the overall structure, providing mechanical protection and installation positioning functions. Both the upper and lower cell units are equipped with independent heat dissipation modules (such as heat sinks), and are fixed between units via connecting pieces 74. The cable interface 72 on the right side is used for electrical connection between the power battery and external systems. Specifically, the inner surface of the shell has pre-set installation rails for the upper and lower cell units, enabling quick plug-and-play assembly of the cell units. Each cell unit layer consists of multiple square battery modules, each with a heat sink fixed to its outer side to increase the heat dissipation area and enhance passive heat dissipation. The pressure plate 73 between modules is an insulated positioning buckle, ensuring both uniform spacing between cell modules and electrical isolation, avoiding the risk of short circuits between modules. The upper and lower battery cells are arranged in parallel, utilizing the internal space of the metal casing to increase energy density, while the thermal conductivity of the casing allows for the conduction and diffusion of some heat. The multiple cables on the right side correspond to functions such as power output and signal acquisition, and the interfaces are designed with waterproof sealing to meet the protection requirements of complex application environments such as automotive.

[0067] After understanding the software and hardware architecture of this application, the following will be combined with... Figure 8 The method for controlling the uniform temperature of the power battery in the embodiments of this application will be described. Figure 8 This is a flowchart illustrating a method for controlling the uniform temperature of a power battery according to an embodiment of this application. The method is applied to a control drive board in a uniform temperature control device, which includes a thermoelectric module comprising multiple thermoelectric modules. The control drive board is connected to the thermoelectric module. The method specifically includes the following steps: Step S801: Real-time monitoring of multiple first temperature values ​​of multiple cells in the power battery and multiple first voltage values ​​of multiple thermoelectric modules corresponding to the multiple cells within a preset time period; each of the multiple first voltage values ​​corresponds one-to-one with each of the multiple first temperature values.

[0068] The preset time period is dynamically set according to the operating conditions of the power battery. Under normal charging and discharging conditions, it is set to 1-5 seconds, and shortened to 0.1-0.5 seconds under extreme conditions such as high-rate charging and discharging, ensuring timely capture of rapid fluctuations in temperature and current. Monitoring of multiple primary temperature values ​​covers key heat-generating areas of the power battery module, including the middle of each cell, the positive and negative electrode tab connections, and the metal connecting plate area. High-precision temperature signal acquisition is achieved through NTC thermistors or thermocouple temperature sensors deployed at these locations. Monitoring of multiple primary voltage values ​​targets the charging and discharging circuit of each cell, acquiring the voltage signal of each individual cell in real time.

[0069] Specifically, the temperature sensor is fixed to the preset monitoring position of the battery cell using thermally conductive adhesive. The sensor leads are shielded before being connected to the data acquisition module to avoid signal distortion caused by electromagnetic interference. The data acquisition module uses a multi-channel synchronous sampling chip to simultaneously receive analog signals from the temperature and current sensors. After analog-to-digital conversion (ADC), the digital signals are transmitted to the main control unit.

[0070] Step S802: Determine the average temperature of the plurality of first temperature values.

[0071] Because power battery packs use multiple thermoelectric modules to independently or in groups to deliver current, the average temperature of the lithium battery cells from left to right (or right to left) is inconsistent. Typically, the battery cells in the middle have a higher temperature, while those at the left and right ends have a lower temperature. To make the temperature of multiple cells more uniform, the average temperature can be used to determine the temperature.

[0072] Step S803: Determine the difference between each of the plurality of first temperature values ​​and the average temperature value to obtain a plurality of temperature differences.

[0073] The multiple first temperature values ​​include monitoring data from the middle of each cell body, the connection point of the positive and negative electrodes, and the metal connecting pieces. Each temperature value is independently calculated to differ from the average temperature. The difference results retain the positive and negative signs: a positive difference indicates that the temperature at that monitoring point is higher than the average level of the module (requiring focused heat dissipation), and a negative difference indicates that the temperature at that monitoring point is lower than the average level of the module (requiring auxiliary heating). Before calculating the difference, it must be confirmed that the timestamps of the average temperature and each first temperature value are completely consistent to ensure that the deviation analysis is based on synchronous data within the same preset time period, avoiding misjudgments caused by comparing data across time periods.

[0074] Step S804: When the target temperature difference is greater than a preset first threshold, determine the adjustment voltage value corresponding to the target temperature difference according to the preset mapping relationship between the temperature difference and the adjustment voltage value, and obtain the target voltage adjustment value; the target temperature difference is any one of the plurality of temperature differences.

[0075] The first threshold is set to 1℃-2℃ based on the thermal management accuracy requirements of the power battery. When the absolute value of the target temperature difference exceeds this threshold, it indicates that the temperature at the corresponding monitoring point deviates from the overall equilibrium level of the module, requiring active temperature control intervention. The preset mapping relationship between the temperature difference and the adjustment voltage value is a non-linear mapping table established based on the output characteristics of the thermoelectric module (the linear correlation between cooling / heating capacity and current), the heat generation characteristics of the battery cell, and a large amount of experimental data. The adjustment voltage value in the mapping relationship ranges from 20% to 100% of the rated voltage of the thermoelectric module, ensuring that the voltage adjustment meets the temperature control requirements while avoiding module overload damage. This mapping relationship is set in segments according to the temperature difference range. The larger the absolute value of the difference, the larger the corresponding adjustment voltage value. Furthermore, the cooling mode and the heating mode adopt symmetrical current adjustment (adjusted by the voltage applied to the thermoelectric module), that is, a positive temperature difference (high temperature) corresponds to a positive current (cooling), and a negative temperature difference (low temperature) corresponds to a reverse current (heating).

[0076] Specifically, in the mapping relationship establishment phase, the actual cooling / heating power of the thermoelectric module under different voltage values ​​is tested experimentally. Combined with heat generation data from the battery cell at different charge / discharge rates, a multi-dimensional dataset is constructed. A polynomial fitting algorithm is used to generate a nonlinear mapping model between temperature differences and adjustment voltage values ​​to ensure the accuracy of the mapping relationship. During actual execution, all temperature differences are iterated in real-time, and target temperature differences with absolute values ​​greater than a first threshold are selected. The temperature control mode (cooling / heating) is determined based on their positive or negative attributes, and the corresponding adjustment voltage value is calculated using the mapping model. By assigning a specific battery cell monitoring area to each thermoelectric module, the target adjustment current value is precisely allocated to the corresponding thermoelectric module in that area, achieving precise temperature control.

[0077] Step S805: Determine the target first voltage value corresponding to the target voltage adjustment value from the plurality of first voltage values.

[0078] The target voltage adjustment value is a thermoelectric module drive voltage parameter determined based on the target temperature difference. The corresponding target first voltage value is the actual charge and discharge voltage data of the cell belonging to the temperature anomaly monitoring point within the same preset time period. Since the heat generation characteristics of the power battery are strongly correlated with the charge and discharge current (current can be determined by voltage) (Joule heat is proportional to the square of the current), determining the target first voltage value can reflect whether the root cause of the temperature anomaly is excessive load, thus providing a basis for the dynamic correction of the subsequent adjustment current value and avoiding over-temperature control or under-temperature control caused by temperature deviation adjustment alone.

[0079] Specifically, firstly, the cell number (e.g., the i-th cell) is determined based on the monitoring point information corresponding to the target temperature difference. Then, based on the acquisition timestamp of the temperature difference, the first voltage value corresponding to that cell at the same timestamp is located, which is the target first voltage value. For example, if the target temperature difference is an increase of 3℃ at the tab connection of the 5th cell, and the acquisition time is t1, then the first voltage value of the 5th cell at time t1 is selected from the dataset as the target first voltage value. After obtaining the target first voltage value, it is further determined whether the voltage value is within the normal load range. When the target first voltage value exceeds 80% of the cell's rated current, it indicates that the temperature abnormality is mainly caused by high load heat generation, and the target voltage adjustment value needs to be maintained or moderately increased. When the target first voltage value is below 30% of the rated current, it indicates that the temperature abnormality may be due to obstructed heat dissipation path or sensor deviation, and the load-independent precise temperature control mode needs to be activated to avoid redundant adjustment current due to insufficient current.

[0080] Step S806: Adjust the voltage of the target thermoelectric module corresponding to the target voltage adjustment value according to the target first voltage value to obtain the second voltage value.

[0081] The target thermoelectric module is positioned based on spatial correspondence, meaning it is precisely coupled to the monitoring point (cell body, tab, or metal connector) corresponding to the target temperature difference. Voltage regulation is based on the target voltage adjustment value, dynamically corrected by combining the target first voltage value with the cell load intensity it reflects. When the target first voltage value is higher than 60% of the cell's rated voltage (high load condition), it indicates a fast cell heat generation rate, requiring an upward adjustment of 10%-20% from the target voltage adjustment value to enhance temperature control response speed. When the target first voltage value is lower than 40% of the rated voltage (low load condition), cell heat generation is gradual, allowing the target voltage adjustment value to be lowered by 5%-15% to avoid energy waste caused by excessive temperature control.

[0082] It is evident that the coordinated consideration of the target voltage adjustment value and the target first current value ensures that the temperature control power of the thermoelectric module matches both the temperature deviation requirement and the actual heat generation characteristics of the battery cell, significantly improving the targeting and accuracy of the temperature control strategy. The switching between forward and reverse currents adapts to the dual needs of heat dissipation and preheating under wide temperature range conditions, overcoming the limitations of traditional heat dissipation methods in low-temperature environments. Through current regulation, the target thermoelectric module can efficiently manage multiple heat sources, including the battery cell body, tabs, and connecting plates, effectively reducing temperature differences between cells and in localized areas, improving the thermal consistency of the power battery module, and providing crucial execution guarantees for improved discharge efficiency and extended lifespan under complex conditions such as fast charging and discharging and extreme temperature environments.

[0083] Step S807: Perform heat control on the target thermoelectric module according to the second voltage value.

[0084] In this system, the target thermoelectric module, acting as the execution unit for heat control, has its cold and hot end switching entirely determined by the direction of the second current value (adjusted via the second voltage). The intensity of heat control is positively correlated with the amplitude of the second current value; the larger the amplitude, the stronger the cooling or heating capacity, allowing for precise matching of different degrees of temperature deviation requirements. Simultaneously, the cold end of the target thermoelectric module is tightly bonded to the metal connecting piece of the battery cell tab via insulating thermally conductive silicone, while the hot end is fixed to the liquid cooling plate via a thermally conductive silicone layer, ensuring rapid heat transfer.

[0085] In one possible embodiment, the method further includes: A1. Obtain the operating condition type of the power battery; the operating condition type includes at least one of the following: fast charging, fast discharging, slow discharging, and slow charging; A2. Obtain the current direction of the thermoelectric module; the current direction includes a first current direction and a second current direction; when the current direction of the thermoelectric module is the first current direction, the current drives the thermoelectric module to make the first heat flow from the hot end face of the thermoelectric module to the cold end face to cool the battery cell; when the current direction of the thermoelectric module is the second current direction, the current drives the thermoelectric module to make the second heat flow from the cold end face of the thermoelectric module to the hot end face to heat the battery cell; A3. When the operating condition is fast charging, the current direction is controlled to be the second current direction and the process is run for a first time to heat the power battery; when the first time reaches a preset threshold, the current direction is controlled to switch back to the first current direction to cool the power battery, so that the temperature of the power battery is at a preset third temperature. A4. When the operating condition is rapid discharge, the current direction is controlled to be the first current direction so that the temperature of the power battery is at the third temperature. A5. When the operating condition is slow discharge, the average temperature of the multiple thermoelectric modules is obtained; if the average temperature is less than or equal to a preset fourth temperature, the thermoelectric module is turned off; if the temperature is greater than the fourth temperature, the current direction of the thermoelectric module is controlled to the first current direction so that the temperature of the power battery is at a preset third temperature. A6. When the operating condition is slow charging, the current direction is controlled to the second current direction and the process is run for a second time to heat the power battery and bring the temperature of the power battery to a second temperature.

[0086] The operating conditions are categorized based on the battery's charge / discharge rate and energy conversion efficiency. During fast charging (≥1C) and fast discharging (≥2C), the cell generates heat rapidly and accumulates significantly. During slow charging (≤0.3C) and slow discharging (≤0.5C), heat generation is gradual but may require low-temperature startup. The first current direction corresponds to the cold end of the thermoelectric module absorbing heat and the hot end releasing heat, while the second current direction reverses the heat transfer path. The third preset temperature is the median of the optimal operating temperature range for the battery (25℃-30℃); the fourth temperature is set at 15℃, serving as the critical threshold for slow discharging where temperature control is not required but cooling is necessary; the second temperature is set at 10℃-15℃ to meet the cell preheating requirement during slow charging. The first time is preset to 5-10 minutes to accommodate the low-temperature preheating requirement at the beginning of fast charging, and the second time is preset to 10-15 minutes to ensure the cell temperature steadily rises to the target range during slow charging.

[0087] Specifically, the system collects real-time charging and discharging current, voltage, and power data, and determines the operating condition type based on a preset rate threshold. A current sensor monitors the polarity of the drive current of the thermoelectric module in real time, and this information is synchronously fed back to the main control unit to provide a basis for direction switching. In fast charging, the initial charging efficiency of the battery cell may be affected by low ambient temperature or insufficient initial temperature. In this case, the current direction is controlled to the second current direction (heating) for a first time (e.g., 8 minutes) to quickly raise the battery cell temperature to near the third temperature (e.g., 28°C), avoiding capacity decay caused by low-temperature charging. After the first time, the battery cell's heat generation rate increases, and the system switches to the first direction (cooling). The TEC module continuously absorbs heat, stabilizing the temperature at around 30°C. In fast discharging, the battery cell generates a large amount of heat in a short time. The current direction is directly controlled to the first current direction, combined with a liquid cooling system for rapid heat dissipation, preventing the temperature from exceeding the 40°C threshold. In slow discharge mode, temperature data is collected by the temperature sensor integrated into the thermoelectric module. If the temperature is ≤15℃ (fourth temperature), the cell generates very little heat and no additional temperature control is required, so the thermoelectric module is turned off to reduce energy consumption. If the temperature is >15℃, the cooling mode is activated to maintain the temperature at 28℃. In slow charging mode, the cell generates very little heat, but low-temperature damage must be avoided. The current direction is controlled to run in the second direction for the second time (e.g., 12 minutes) to preheat the cell temperature to 12℃ (second temperature), ensuring charging safety while avoiding overheating and energy waste.

[0088] As can be seen, by coordinating the control of operating conditions and current direction, adaptive temperature control of the TEC module under different charging and discharging scenarios is achieved, solving the problems of slow response speed and poor wide-temperature range adaptability of existing TEC technologies. Differentiated temperature control strategies for different operating conditions (fast charging and discharging focusing on heat dissipation / preheating followed by heat dissipation, slow charging and discharging focusing on preheating / on-demand heat dissipation) match the heat generation characteristics and temperature requirements of the power battery, avoiding the inefficiency or temperature runaway caused by a single temperature control mode. This effectively improves charging and discharging efficiency, extends battery cycle life, and reduces the energy consumption of the thermoelectric module, providing comprehensive operating condition adaptability assurance for the efficient and stable operation of the power battery.

[0089] The following is combined Figure 9 The temperature control device for the power battery in the embodiments of this application will be described. Figure 9 This is a schematic diagram of the structure of a power battery temperature equalization control device provided in an embodiment of this application, as shown below. Figure 9 As shown, the temperature control device 900 of the power battery includes a processor 910, a memory 920, a communication interface 930, and one or more programs 921. The processor 910 is connected to the memory 920 and the communication interface 930 via an internal communication bus.

[0090] The one or more programs 921 are stored in the memory 920 and configured to be executed by the processor 910. The one or more programs 921 include functions for performing the aforementioned... Figure 8 Instructions for any step in an embodiment of a method for controlling the uniform temperature of a power battery.

[0091] The processor 910 can be a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It can implement or execute the various exemplary logic blocks, cells, and circuits described in conjunction with the disclosure of this application. The processor can also be a combination that implements computational functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc. The communication unit can be a communication interface, a transceiver, a transceiver circuit, etc., and the storage unit can be a memory.

[0092] The memory 920 can be volatile memory or non-volatile memory, or both. The non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. The volatile memory can be random access memory (RAM), which is used as an external cache. By way of example, but not limitation, many forms of random access memory (RAM) are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate synchronous DRAM (DDR SDRAM), enhanced synchronous DRAM (ESDRAM), synchronous linked DRAM (SLDRAM), and direct rambus RAM (DR RAM).

[0093] It is understood that the temperature equalization control device 900 for the power battery may include more or fewer structural components than those shown in the above structural block diagram, such as a power module, physical buttons, a Wi-Fi module, a speaker, a Bluetooth module, sensors, a display module, etc., without limitation here. It is also understood that this split-type ultrasonic induction device can be equipped with, for example... Figure 1 The diagram shows the architecture of the thermal management system for the power battery.

[0094] This application also provides a power battery temperature equalization control system, wherein the split-type ultrasonic induction system includes any part as described in the above embodiment of a power battery temperature equalization control device.

[0095] This application also provides a computer program product, which includes a non-transitory computer-readable storage medium storing a computer program operable to cause a computer to perform some or all of the steps of any of the methods described in the above method embodiments. The computer program product can be a software installation package, and the computer includes a temperature equalization control device for a power battery.

[0096] It should be noted that, for the sake of simplicity, the above embodiments are all described as a series of actions. Those skilled in the art should understand that this application is not limited to the described order of actions, as some steps in the embodiments of this application can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions, steps, modules, or units involved are not necessarily essential to the embodiments of this application.

[0097] In the above embodiments, the descriptions of each embodiment in this application have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0098] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. This program can be stored in a computer-readable storage medium, and when executed, it can include the processes described in the above method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as ROM or random access memory (RAM), magnetic disks, or optical disks.

[0099] The steps of the methods or algorithms described in the embodiments of this application can be implemented in hardware or by a processor executing software instructions. The software instructions can consist of corresponding software modules, which can be stored in RAM, flash memory, ROM, EPROM, electrically erasable programmable read-only memory (EEPROM), registers, hard disk, portable hard disk, read-only optical disk (CD-ROM), or any other form of storage medium well known in the art. An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. Furthermore, the ASIC can reside in a terminal device or management device. Alternatively, the processor and storage medium can exist as discrete components in the terminal device or management device.

[0100] Those skilled in the art will recognize that, in one or more of the examples above, the functions described in the embodiments of this application can be implemented, in whole or in part, by software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. This computer program product includes one or more computer instructions. When these computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, microwave, etc.) means. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device such as a server or data center that integrates one or more available media. The available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., digital video discs (DVDs)), or semiconductor media (e.g., solid-state disks (SSDs)).

[0101] The modules / units included in the various devices and products described in the above embodiments can be software modules / units, hardware modules / units, or a combination of both. For example, for devices and products applied to or integrated into a chip, all modules / units can be implemented using hardware methods such as circuits, or at least some modules / units can be implemented using software programs that run on a processor integrated within the chip, while the remaining (if any) modules / units can be implemented using hardware methods such as circuits. For devices and products applied to or integrated into a chip module, all modules / units can be implemented using hardware methods such as circuits. Different modules / units can be located in the same component (e.g., chip, circuit module, etc.) or different components of the chip module, or at least some modules / units can be implemented using hardware methods such as circuits. The implementation is achieved through a software program that runs on the processor integrated within the chip module. The remaining modules / units (if any) can be implemented using hardware methods such as circuits. For various devices and products applied to or integrated into terminal equipment, each of their modules / units can be implemented using hardware methods such as circuits. Different modules / units can be located in the same component (e.g., chip, circuit module, etc.) or different components within the terminal equipment. Alternatively, at least some modules / units can be implemented through a software program that runs on the processor integrated within the terminal equipment, while the remaining modules / units (if any) can be implemented using hardware methods such as circuits.

[0102] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the embodiments of this application. It should be understood that the above descriptions are merely specific embodiments of the embodiments of this application and are not intended to limit the protection scope of the embodiments of this application. Any modifications, equivalent substitutions, improvements, etc., made on the basis of the technical solutions of the embodiments of this application should be included within the protection scope of the embodiments of this application.

Claims

1. A temperature equalization control device for a power battery, characterized in that, The power battery includes multiple cells, with a first heat-conducting plate disposed between each pair of cells, and the electrodes of each pair of cells connected by a metal connecting piece. The temperature equalization control device includes: A thermoelectric module includes a plurality of thermoelectric modules disposed between a first end face and a second end face; the first end face and the second end face are disposed opposite to each other. A liquid cooling plate is disposed at a preset mounting position on the first end face; The second heat-conducting plate includes a third end face and a fourth end face. The third end face is attached to the second end face, and the fourth end face is attached to the metal connecting piece. The second heat-conducting plate is also attached to the first heat-conducting plate. A phase change medium is disposed between the metal connecting piece and the second heat-conducting plate. The third end face and the fourth end face are disposed opposite to each other.

2. The temperature control device as described in claim 1, characterized in that, Each of the plurality of thermoelectric modules includes a first electrode and a second electrode; the first electrode and the second electrode are respectively connected to the control drive circuit of the temperature equalization control device. The control drive circuit is used to adjust the preset current parameters of the drive current applied between the first electrode and the second electrode. The current parameters include current magnitude and current direction; The thermoelectric module adjusts the temperature type of the first end face and the second end face according to the current direction to achieve switching between the cold end face and the hot end face; In addition, the first and second temperatures corresponding to the first and second end faces are adjusted according to the magnitude of the current; the heat conduction parameters of the first and second end faces are determined according to the first and second temperatures, so that the thermoelectric module selectively absorbs or releases heat to the area corresponding to the second heat-conducting plate and / or the metal connecting piece.

3. The temperature control device as described in claim 1, characterized in that, A thermally conductive buffer layer is provided between the first end face and the liquid cooling plate. The thermally conductive buffer layer is a thermoelastic material with a preset thermal conductivity. The thermally conductive buffer layer is used to provide a heat conduction path between the thermoelectric module and the liquid cooling plate, and to absorb the mechanical impact generated when the liquid cooling plate moves. The first end face of the thermoelectric module is fixed to the liquid cooling plate by welding.

4. The temperature equalization control device according to any one of claims 1-3, characterized in that, The thermoelectric module is arranged along the height direction of the power battery; the power battery includes multiple thermoelectric modules; at least one of the multiple thermoelectric modules is arranged in the upper region of the power battery, and / or at least one of the thermoelectric modules is arranged in the lower region of the power battery.

5. The temperature equalization control device as described in claim 4, characterized in that, The multiple thermoelectric modules of the thermoelectric module are arranged along the arrangement direction of the cells in the power battery, and the first region where the cells are located is correspondingly arranged with the second region of the multiple thermoelectric modules, so as to achieve heat regulation of the first region.

6. The temperature equalization control device according to any one of claims 1-3, characterized in that, The liquid cooling plate has a liquid inlet and a liquid outlet; a thermally conductive silicone layer is provided between the liquid cooling plate and the first end face, the thermally conductive silicone layer is attached between the liquid cooling plate and the first end face, and is used to transfer the heat of the first end face to the liquid cooling plate, and to provide buffer protection between the liquid cooling plate and the first end face.

7. The temperature equalization control device according to any one of claims 1-3, characterized in that, The metal connecting piece includes a bent portion and two flattened portions. The bent portion protrudes away from the battery cell electrode relative to the flattened portion of the metal connecting piece. The two flattened portions are respectively fixedly connected to the battery cell electrode by laser welding.

8. The temperature equalization control device according to any one of claims 1-3, characterized in that, The two adjacent metal connecting pieces and the second heat-conducting plate form a second space, the phase change medium is disposed in the second space and is attached to the second heat-conducting plate; the phase change medium is an insulating and buffering material used to absorb mechanical vibration between the multiple cells.

9. A method for temperature control of a power battery, characterized in that, A control drive board is used in a temperature equalization control device, the temperature equalization control device including a thermoelectric module, the thermoelectric module including multiple thermoelectric modules, the control drive board being connected to the thermoelectric module, the method including: The system monitors multiple first temperature values ​​of multiple cells in the power battery and multiple first voltage values ​​of multiple thermoelectric modules corresponding to the multiple cells in real time within a preset time period; each of the multiple first voltage values ​​corresponds one-to-one with each of the multiple first temperature values. Determine the average temperature of the plurality of first temperature values; Determine the difference between each of the plurality of first temperature values ​​and the average temperature value to obtain a plurality of temperature difference values; When the target temperature difference is greater than a preset first threshold, the adjustment voltage value corresponding to the target temperature difference is determined according to the preset mapping relationship between the temperature difference and the adjustment voltage value, thus obtaining the target voltage adjustment value; the target temperature difference is any one of the plurality of temperature differences; Determine the target first voltage value corresponding to the target voltage adjustment value from the plurality of first voltage values; The voltage of the target thermoelectric module corresponding to the target voltage adjustment value is adjusted according to the target first voltage value to obtain the second voltage value; The target thermoelectric module is thermally controlled based on the second voltage value.

10. The method as described in claim 9, characterized in that, The method further includes: Obtain the operating condition type of the power battery; the operating condition type includes at least one of the following: fast charging, fast discharging, slow discharging, and slow charging; The current direction of the thermoelectric module is obtained; the current direction includes a first current direction and a second current direction; when the current direction of the thermoelectric module is the first current direction, the current drives the thermoelectric module to make the first heat flow from the hot end face of the thermoelectric module to the cold end face to cool the battery cell; when the current direction of the thermoelectric module is the second current direction, the current drives the thermoelectric module to make the second heat flow from the cold end face of the thermoelectric module to the hot end face to heat the battery cell; When the operating condition is fast charging, the current direction is controlled to be the second current direction and the process is run for a first time to heat the power battery; when the first time reaches a preset threshold, the current direction is controlled to switch back to the first current direction to cool the power battery, so that the temperature of the power battery is at a preset third temperature. When the operating condition is rapid discharge, the current direction is controlled to be the first current direction so that the temperature of the power battery is at the third temperature. When the operating condition is slow discharge, the average temperature of the multiple thermoelectric modules is obtained; if the average temperature is less than or equal to a preset fourth temperature, the voltage output to the thermoelectric module is stopped; if the temperature is greater than the fourth temperature, the current direction is controlled to the first current direction so that the temperature of the power battery is at a preset third temperature. When the operating condition is slow charging, the current direction is controlled to the second current direction and the process is run for a second time to heat the power battery and bring the temperature of the power battery to a second temperature.

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