Intelligent temperature control self-heating battery and temperature control method

Abstract

The application provides a kind of intelligent temperature control self-heating battery and temperature control method.Intelligent temperature control self-heating battery includes battery cell and BMS battery management system, battery cell includes self-heating battery pole piece, diaphragm, electrolyte and shell;Diaphragm and self-heating battery pole piece are continuously alternately stacked, and are adhered and fixed to form an integrated structure and are packaged in the shell interior;Electrolyte fills the shell interior;BMS battery management system is electrically connected with the electrode in self-heating battery pole piece, for controlling the start-stop and heating power of electrothermal conversion layer according to the real-time temperature of battery cell.The application combines heating structure and electrode into an integrated structure, realizes uniform heating inside battery cell;Through the accurate temperature control logic of BMS, the overall temperature difference inside battery cell is controlled within 3 DEG C, which fundamentally improves temperature uniformity.

Description

Technical Field

[0001] This invention relates to the field of thermal management technology for new energy power batteries, and in particular to an intelligent temperature-controlled self-heating battery and a temperature control method. Background Technology

[0002] In low-temperature environments (typically below 0°C), power batteries face core challenges such as decreased electrolyte conductivity, increased electrode charge transfer resistance, and reduced lithium-ion migration rate. These issues directly lead to decreased charging speed and discharge power, and may even pose safety risks due to lithium dendrites piercing the separator. Existing external heating methods suffer from inherent drawbacks such as low heating efficiency and poor temperature uniformity. Some internal heating solutions increase the size of the battery system or cannot achieve precise adjustment of heating power, making it difficult to simultaneously meet the core requirements of heating efficiency, temperature uniformity, and battery cycle life. Summary of the Invention

[0003] This invention provides an intelligent temperature-controlled self-heating battery and a temperature control method to solve one or more technical problems encountered in the prior art.

[0004] In a first aspect, the present invention provides an intelligent temperature-controlled self-heating battery, comprising: a battery cell and a battery management system (BMS), wherein the battery cell includes self-heating battery electrodes, a separator, an electrolyte, and a casing; the separator and the self-heating battery electrodes are continuously and alternately stacked, bonded, and fixed together to form an integral structure and encapsulated inside the casing; the electrolyte fills the interior of the casing; the self-heating battery electrodes include: An insulating composite substrate formed by hot-pressing at least two layers of polymer film; An electrothermal conversion layer is disposed inside the insulating composite substrate, and the electrothermal conversion layer is used to generate heat when energized; At least one pair of electrodes forms an electrical connection with the electrothermal conversion layer; Current collector layer and electrode active material layer disposed on the first surface of the insulating composite substrate; A current collector layer and an electrode active material layer are disposed on the second surface of the insulating composite substrate; The BMS battery management system is electrically connected to the electrodes in the self-heating battery electrode sheet, and is used to control the start / stop of the electrothermal conversion layer and the heating power according to the real-time temperature of the battery cell.

[0005] In a preferred embodiment, the BMS battery management system includes a temperature acquisition module for acquiring temperature data of the cell interior, electrode surface, or tab area.

[0006] In a preferred embodiment, the BMS battery management system is configured with a low-temperature preheating strategy, a target temperature control strategy, and a fast-charging preheating strategy. The low-temperature preheating strategy is as follows: when the detected temperature is lower than the set temperature, the electrothermal conversion layer is automatically activated to perform uniform preheating. The target temperature control strategy is as follows: when the cell temperature reaches the preset temperature range, reduce the heating power or stop heating. The fast charging preheating strategy is to automatically preheat the battery cells to a specified temperature or above before the fast charging command is initiated.

[0007] In a preferred embodiment, the electrothermal conversion layer is at least one metal oxide semiconductor material selected from fluorine-doped tin dioxide, antimony-doped tin dioxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, vanadium pentoxide, indium zinc oxide, molybdenum-doped indium oxide, and indium tin oxide. It is prepared as a conductive heating film on the insulating composite substrate using a vacuum deposition process. The thickness of the electrothermal conversion layer is 15 nm to 50 nm. The electrode is disposed on the electrothermal conversion layer and electrically connected to it, and the electrode is connected to a power supply.

[0008] In a preferred embodiment, the electrothermal conversion layer is one or more of graphene, carbon nanotubes, metal alloys, or conductive polymers, and is prepared as a conductive heating film on the composite substrate by physical vapor deposition, printing, or coating processes; the electrode is disposed on the electrothermal conversion layer and electrically connected to the electrothermal conversion layer, and the electrode is connected to a power supply.

[0009] In a preferred embodiment, the power supply for the electrothermal conversion layer is a low-voltage DC power supply, powered by the battery cell itself or an external auxiliary power supply; and the self-heating function and the charging and discharging function are independent of each other and do not interfere with each other.

[0010] In a preferred embodiment, the electrothermal conversion layer has a PTC self-limiting temperature characteristic. When the temperature of the electrothermal conversion layer rises to the critical temperature, its resistance value will increase sharply, automatically limiting the heating power so that the maximum heating temperature of the battery cell does not exceed the set temperature threshold.

[0011] In a preferred embodiment, the intelligent temperature-controlled self-heating battery has a minimum operating temperature of less than -40°C, making it highly adaptable to cold environments.

[0012] In a preferred embodiment, when the electrothermal conversion layer is in operation, the overall temperature difference inside the battery cell is less than or equal to 3°C, and the temperature uniformity is excellent.

[0013] In a preferred embodiment, the current collector layer on the first surface of the insulating composite substrate is a positive current collector layer, and the corresponding active material layer is a positive active material layer; the current collector layer on the second surface of the insulating composite substrate is a negative current collector layer, and the corresponding active material layer is a negative active material layer. Alternatively, the current collector layer on the first surface of the insulating composite substrate is a positive electrode current collector layer, and the corresponding active material layer is a positive electrode active material layer; the current collector layer on the second surface of the insulating composite substrate is also a positive electrode current collector layer, and the corresponding active material layer is a positive electrode active material layer. Alternatively, the current collector layer on the first surface of the insulating composite substrate is a negative electrode current collector layer, and the corresponding active material layer is a negative electrode active material layer; the current collector layer on the second surface of the insulating composite substrate is also a negative electrode current collector layer, and the corresponding active material layer is a negative electrode active material layer.

[0014] Secondly, the present invention provides a temperature control method for an intelligent temperature-controlled self-heating battery, based on the intelligent temperature-controlled self-heating battery described in the above embodiments, comprising the following steps: (1) The BMS battery management system collects cell temperature data in real time; (2) Determine whether the cell temperature is lower than the preset preheating threshold; (3) If the temperature is below the preset preheating threshold, power is supplied to the electrothermal conversion layer in the self-heating battery electrode to make the multilayer composite electrode heat up uniformly. (4) When the cell temperature enters the preset optimal operating range, reduce or cut off the power supply to the electrothermal conversion layer; (5) During the charging and discharging process of the battery, the heating power of the electrothermal conversion layer is dynamically adjusted to maintain the cell temperature within the optimal operating range.

[0015] In a preferred embodiment, in a low-temperature environment of -40°C to 0°C, the preheating time of the intelligent temperature-controlled self-heating battery does not exceed the set time, which can quickly meet the conditions for fast charging and high-current discharge.

[0016] One of the above technical solutions has the following advantages or beneficial effects: High heating efficiency and low energy loss: This invention embeds the electrothermal conversion layer inside the composite substrate of the cell electrodes, rather than adding heating devices outside the cell or between cells. During heating, heat is generated directly inside the cell, shortening the heat conduction distance to less than one percent of that of traditional external heating schemes, significantly reducing heat loss. Both measured data and theoretical calculations show that the heating efficiency of this invention is significantly improved compared to traditional external heating schemes. In extremely cold environments of -40℃, preheating a single cell from -40℃ to 0℃ requires only less than 5% of the single cell's capacity, and the preheating time is controlled within 45 seconds. This preheating energy consumption level is far lower than publicly reported external heating schemes, greatly reducing the impact of low-temperature preheating on vehicle range or energy storage station discharge efficiency.

[0017] Excellent temperature uniformity effectively extends battery cycle life: The electrothermal conversion layer of this invention is a planar uniform heating structure, laid out across the entire surface of the composite substrate. During heating, the entire electrode area generates heat synchronously and uniformly, rather than relying on local heating units for heat transfer. Combined with the multi-point temperature acquisition and closed-loop power regulation logic of the BMS, the overall temperature difference inside the cell can be controlled within 3°C, and in some optimized embodiments, it can even be controlled within 2°C. This level of temperature uniformity is far below the industry-accepted safety limit of 5°C temperature difference. During the charging and discharging process, the electrochemical reaction rate and degradation rate of each region inside the battery are basically the same, avoiding the problem of excessively rapid local degradation. Actual test data shows that under the same extremely cold environmental cycling conditions, the battery using the technical solution of this invention has a cycle life that is more than 20% longer than that of the battery using the traditional external heating solution.

[0018] Intelligently adaptable to all operating conditions with high thermal safety: The BMS of this invention integrates three core temperature control strategies: low-temperature preheating, target temperature control, and fast-charging preheating, covering all operating conditions such as battery resting, charging, driving discharge, and fast charging. The heating circuit and charging / discharging circuit operate independently and in parallel. The BMS collects temperature data in real time throughout the entire operation and dynamically adjusts the heating power through closed-loop feedback control logic, achieving stepless and precise adjustment of the heating power, rather than simple on / off control. More importantly, the PTC self-limiting temperature characteristic built into the electrothermal conversion layer forms a second layer of safety protection: when the temperature of the electrothermal conversion layer rises to the set critical temperature, its resistance value will suddenly increase by several orders of magnitude, automatically limiting the current passing through and actively reducing the heating power to within the safe threshold. Even if the temperature acquisition module of the BMS fails, this physical characteristic can ensure that the battery will not experience thermal runaway due to overheating, greatly improving the inherent safety of the system.

[0019] Compact structure and strong adaptability: The heating structure of this invention adopts a thin-film design, embedding the electrothermal conversion layer inside the composite substrate of the cell electrode. This eliminates the need for additional installation space for heating devices within the battery pack, as well as the need for bulky external wiring and high-power switching devices. This integrated design results in minimal increase in the overall battery volume, perfectly adapting to the installation space of existing new energy vehicles and energy storage power stations. Furthermore, the technical solution of this invention is adaptable to power batteries with different chemical systems, such as lithium iron phosphate, ternary lithium, and solid-state batteries. It requires no significant adjustments to the existing battery assembly process; only the addition of composite substrate hot pressing and electrothermal conversion layer coating / printing processes to the existing lamination process is needed, resulting in excellent mass production processability. In addition, this technical solution can be applied not only to power batteries for new energy vehicles but also to large-scale energy storage power stations, mobile power supplies in extremely cold environments, and all other energy storage scenarios requiring low-temperature performance, demonstrating a wide range of applications.

[0020] The above overview is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features of the invention will become readily apparent from the accompanying drawings and the following detailed description. Attached Figure Description

[0021] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in the invention and should not be construed as limiting the scope of the invention.

[0022] Figure 1 This is a schematic diagram of the overall structure and connection of the intelligent temperature-controlled self-heating battery in this embodiment. Detailed Implementation

[0023] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0024] In a first aspect, the present invention provides an intelligent temperature-controlled self-heating battery, see [link to previous article]. Figure 1 As shown, the intelligent temperature-controlled self-heating battery includes a battery cell and a BMS battery management system 210. The battery cell includes self-heating battery electrodes, a separator 130, an electrolyte 120, and a casing 110. The separator 130 and the self-heating battery electrodes are continuously and alternately stacked, bonded, and fixed to form an integral structure and encapsulated inside the casing 110. The electrolyte 120 fills the interior of the casing. The self-heating battery electrodes include: An insulating composite substrate 100 formed by hot-pressing at least two layers of polymer film; An electrothermal conversion layer 200 is disposed inside the insulating composite substrate 110, and the electrothermal conversion layer 200 is used to generate heat when energized; At least one pair of electrodes 300 are electrically connected to the electrothermal conversion layer 200; A current collector layer 400 and an electrode active material layer 500 are disposed on the first surface of the insulating composite substrate 100; A current collector layer 400 and an electrode active material layer 500 are disposed on the second surface of the insulating composite substrate 100; The BMS battery management system 210 is electrically connected to the electrode 300 in the self-heating battery electrode sheet, and is used to control the start-up and shutdown of the electrothermal conversion layer 200 and the heating power according to the real-time temperature of the battery cell.

[0025] In one specific embodiment, the BMS battery management system 210 includes a temperature acquisition module for acquiring temperature data inside the battery cell, on the electrode surface, or in the tab area.

[0026] In one specific embodiment, the BMS battery management system is configured with a low-temperature preheating strategy, a target temperature control strategy, and a fast-charging preheating strategy. The low-temperature preheating strategy is as follows: when the detected temperature is lower than the set temperature, the electrothermal conversion layer is automatically activated to perform uniform preheating. The target temperature control strategy is as follows: when the cell temperature reaches the preset temperature range, reduce the heating power or stop heating. The fast charging preheating strategy is to automatically preheat the battery cells to a specified temperature or above before the fast charging command is initiated.

[0027] In one specific embodiment, the electrothermal conversion layer 200 is at least one metal oxide semiconductor material selected from fluorine-doped tin dioxide, antimony-doped tin dioxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, vanadium pentoxide, indium zinc oxide, molybdenum-doped indium oxide, and indium tin oxide. It is prepared as a conductive heating film on the composite substrate by a vacuum deposition process. The thickness of the electrothermal conversion layer 200 is 15nm~50nm. The electrode 300 is disposed on the electrothermal conversion layer 200 and electrically connected to the electrothermal conversion layer 200, and the electrode 300 is connected to a power supply.

[0028] In one specific embodiment, the electrothermal conversion layer 200 is one or more of graphene, carbon nanotubes, metal alloys or conductive polymers, and is prepared as a conductive heating film on the insulating composite substrate by physical vapor deposition, printing or coating processes; the electrode 300 is disposed on the electrothermal conversion layer 200 and electrically connected to the electrothermal conversion layer 200, and the electrode 300 is connected to a power supply.

[0029] In one specific embodiment, the power supply for the electrothermal conversion layer 200 is a low-voltage DC power supply, powered by the battery cell itself or an external auxiliary power supply; and the self-heating function and the charging and discharging function are independent of each other and do not interfere with each other.

[0030] In one specific embodiment, the electrothermal conversion layer 200 has a PTC self-limiting temperature characteristic. When the temperature of the electrothermal conversion layer 200 rises to the critical temperature, its resistance value will increase sharply, automatically limiting the heating power so that the maximum heating temperature of the battery cell does not exceed the set temperature threshold.

[0031] In one specific embodiment, the minimum operating temperature of the intelligent temperature-controlled self-heating battery is less than -40°C, making it highly adaptable to cold environments.

[0032] In one specific embodiment, when the electrothermal conversion layer 200 is in operation, the overall temperature difference inside the battery cell is less than or equal to 3°C, and the temperature uniformity is excellent.

[0033] In one specific embodiment, the current collector layer 400 on the first surface of the insulating composite substrate 100 is a positive current collector layer, and the corresponding active material layer 500 is a positive active material layer; the current collector layer 400 on the second surface of the insulating composite substrate 100 is a negative current collector layer, and the corresponding active material layer 500 is a negative active material layer. Alternatively, the current collector layer 400 on the first surface of the insulating composite substrate 100 may be a positive current collector layer, and the corresponding active material layer 500 may be a positive active material layer; the current collector layer 400 on the second surface of the insulating composite substrate 100 may also be a positive current collector layer, and the corresponding active material layer 500 may be a positive active material layer. Alternatively, the current collector layer 400 on the first surface of the insulating composite substrate 100 may be a negative electrode current collector layer, and the corresponding active material layer 500 may be a negative electrode active material layer; the current collector layer 400 on the second surface of the insulating composite substrate 100 may also be a negative electrode current collector layer, and the corresponding active material layer 500 may be a negative electrode active material layer.

[0034] Secondly, the present invention provides a temperature control method for an intelligent temperature-controlled self-heating battery, based on the intelligent temperature-controlled self-heating battery described in the above embodiments, comprising the following steps: (1) The BMS battery management system collects cell temperature data in real time; (2) Determine whether the cell temperature is lower than the preset preheating threshold; (3) If the temperature is below the preset preheating threshold, power is supplied to the electrothermal conversion layer in the self-heating battery electrode to make the multilayer composite electrode heat up uniformly. (4) When the cell temperature enters the preset optimal operating range, reduce or cut off the power supply to the electrothermal conversion layer; (5) During the charging and discharging process of the battery, the heating power of the electrothermal conversion layer is dynamically adjusted to maintain the cell temperature within the optimal operating range.

[0035] In a preferred embodiment, in a low-temperature environment of -40°C to 0°C, the preheating time of the intelligent temperature-controlled self-heating battery does not exceed the set time, which can quickly meet the conditions for fast charging and high-current discharge.

[0036] Core logic of the product technical solution: The intelligent temperature-controlled self-heating battery of this invention comprises two core components: a battery cell and a battery management system (BMS). The battery cell is an integrated innovation based on the traditional lithium battery structure. The core improvement lies in embedding the electrothermal conversion layer within the composite substrate of the cell electrodes, rather than adding additional heating devices outside the cell or between cells. See also... Figure 1 As shown, its specific structure is as follows: the battery cell consists of four parts: self-heating battery electrode, separator 130, electrolyte 120 and shell 110; the separator 130 and the self-heating battery electrode are continuously and alternately stacked and bonded together in the order of "negative electrode-separator-positive electrode-separator" to form a complete battery cell electrode assembly structure, which is then encapsulated inside the shell 110; the electrolyte 120 fills all the pore spaces inside the shell 110 to ensure the smooth flow of ion migration channels.

[0037] Among them, the self-heating battery electrode is the core foundation for realizing the "heating + charging and discharging" composite function. It adopts a multi-layer composite integrated structure, rather than a simple splicing of traditional electrodes and heating devices; see also Figure 1 As shown, it specifically includes: an insulating composite substrate 100 formed by hot-pressing at least two polymer films; an electrothermal conversion layer 200 disposed inside the insulating composite substrate 100; at least a pair of electrodes 300 electrically connected to the electrothermal conversion layer 200; and a current collector layer 400 and an active material layer 500 respectively disposed on the two surfaces of the insulating composite substrate 100. The insulating composite substrate 100 here serves as both the support base for the current collector layer 400 and the insulating mounting base for the electrothermal conversion layer 200, completely isolating the electrothermal conversion layer 200 and the current collector layer 400 at the electrical level to prevent interference between the heating circuit and the charging / discharging circuit. The electrothermal conversion layer 200 is the core of the entire heating structure. It is led out to the BMS heating control interface outside the battery through the electrode 300 and generates heat when energized to directly heat the inside of the cell. The insulating composite substrate 110 has a current collector layer 400 and an electrode active material layer 500 on both surfaces. It can be designed into a "two-sided positive electrode layer", "two-sided negative electrode layer" or "one positive and one negative" layout structure according to actual needs to adapt to different cell design requirements.

[0038] The electrothermal conversion layer 200 is the core component for realizing the heating function. Its technical solution can be selected from high-stability metal oxide semiconductor materials or high-heating-efficiency carbon-based / metal alloy materials according to the needs of different application scenarios. Both solutions adopt thin film molding process to control the overall thickness within the micron range, without significantly increasing the overall volume of the electrode. At the same time, the electrode 300 built into the electrothermal conversion layer 200 ensures a reliable electrical connection with the heating circuit, avoiding problems such as local overheating and insufficient heating power.

[0039] The BMS (Battery Management System) 210 is the core control unit for intelligent temperature control. It is electrically connected to the electrodes 300 within the self-heating battery plates, enabling real-time acquisition of cell temperature data and precise control of the start / stop and heating power of the electrothermal conversion layer based on the actual cell temperature and operating conditions. Specifically, the BMS consists of four parts: a temperature acquisition module, a control module, a drive module, and a host computer interaction module. The temperature acquisition module uses multiple temperature sensors located inside the cell, on the electrode surface, or in the tab area to collect real-time battery temperature data with an accuracy of ±0.1℃. The control module has a built-in storage unit, logic operation unit, and PID precision regulator. It compares the collected actual temperature data with a preset temperature threshold range to calculate the target heating power, and then adjusts the actual heating power of the electrothermal conversion layer through the drive module. The host computer interaction module can interact with the vehicle's central control system or user terminal, uploading battery temperature data and heating operation status in real time, and can also receive remote preheating commands from users.

[0040] Core logic of the method and technical solution: This invention also provides a temperature control method based on the aforementioned intelligent temperature-controlled self-heating battery. Implemented by the closed-loop control logic of the BMS, the core of this method is to achieve precise temperature control under different ambient temperatures and operating conditions through real-time acquisition of cell temperature, logical judgment, and dynamic power adjustment, ensuring the battery is always within its optimal operating temperature range. Its core strategies can be divided into three main categories, each operating independently yet collaboratively, covering all battery operating conditions from resting and charging to driving discharge: Low-temperature preheating strategy: When the vehicle starts or receives a charging command, the BMS first reads the real-time temperature data of the battery cell through the temperature acquisition module. If the temperature is lower than the preset start-up threshold, the BMS will turn on the heating circuit and start the electrothermal conversion layer to heat the battery cell evenly with the set power. During the heating process, the temperature acquisition module continuously transmits the real-time temperature data to the control module of the BMS, and maintains the stability of the heating power through PID adjustment logic to ensure that all areas inside the battery cell heat up synchronously and avoid excessive local temperature differences.

[0041] Target temperature control strategy: When the cell temperature rises to near the upper limit of the optimal operating temperature range, the BMS control module will gradually reduce the heating power to allow the cell temperature to gradually enter and stabilize within the optimal range; if the cell temperature continues to rise and exceeds the upper limit of the optimal range, the BMS will immediately cut off the heating circuit and stop heating; if the cell temperature drops below the lower limit of the optimal range after heating stops, the BMS will reconnect the heating circuit to maintain the dynamic stability of the cell temperature.

[0042] Fast charging preheating strategy: When a user schedules fast charging through the vehicle's infotainment system or mobile app, or when the vehicle's navigation system detects a fast charging scenario at a charging station, the BMS automatically activates the heating circuit in advance to preheat the battery cells to a specified temperature or above. After preheating, the BMS sends a fast charging permission signal to the vehicle's charging control system, at which point the charging control system initiates the high-current fast charging. During fast charging, the BMS continuously collects battery cell temperature data and dynamically adjusts the heating power based on the actual charging current and ambient temperature to ensure that the battery cell temperature remains within the optimal range for fast charging. Actual test data shows that, using this strategy, the fast charging power of the battery in extremely cold environments (-20℃) can be restored to more than 80% of that under normal temperature conditions, and the charging speed is more than doubled compared to when no preheating is used.

[0043] Preferred technical solution: As a preferred embodiment of this solution, the electrothermal conversion layer 200 adopts a dual-layer composite heating layer design, that is, it uses both metal oxide semiconductor materials and carbon-based / metal alloy materials to prepare the heating layer, combining the advantages of the two types of materials to further improve heating efficiency and temperature uniformity. The electrode 300 is prepared using a mesh printing process, which increases the contact area with the heating layer, reduces contact resistance, and avoids the risk of local overheating. The temperature acquisition module of the BMS adopts multi-point temperature acquisition logic, with temperature sensors arranged at key temperature measurement points inside the cell, on the electrode surface, or in the tab area. The collected data is weighted and averaged to serve as the reference value for temperature control. At the same time, the control module of the BMS integrates the ampere-hour integral method, the SOC estimation algorithm, and the temperature prediction algorithm based on machine learning. It can estimate the SOC (State of Charge) of the battery in real time and dynamically adjust the heating power based on the SOC data, minimizing the consumption of battery power during the heating process while ensuring the heating effect.

[0044] Example 1: Intelligent Temperature Control Self-Heating Battery This embodiment is a product embodiment adapted to the application scenario of new energy vehicles, and is a typical application solution that deeply integrates the heating structure with the battery cell electrode.

[0045] Overall structure: The intelligent temperature-controlled self-heating battery in this embodiment, see [link / reference]. Figure 1 As shown, the core structure consists of five parts: self-heating battery electrode, separator 130, electrolyte 120, casing 110, and BMS battery management system 210. Among them, the separator 130 and the self-heating battery electrode are continuously and alternately stacked and bonded in the order of "negative electrode-separator-positive electrode-separator" to form a complete cell electrode assembly structure. The cell electrode assembly is encapsulated inside the casing 110, and the electrolyte 120 fills all the pore spaces inside the casing 110 to ensure the smooth flow of ion migration channels. The BMS battery management system is electrically connected to the electrothermal conversion layer 200 inside the cell through the tab leads to control the heating process.

[0046] The self-heating battery electrode structure is a multi-layered composite integrated structure, consisting of an insulating composite substrate 100, an electrothermal conversion layer 200, an electrode 300, a current collector layer 400, and an active material layer 500. The insulating composite substrate 100 serves as the mounting base for the entire electrode structure. It is formed by hot-pressing two layers of high-strength, highly insulating polymer films, which are respectively the upper and lower insulating substrates. Specific materials can include polyimide (PI), polyethylene terephthalate (PET), or other engineering plastic films with similar temperature resistance and insulation properties. The electrothermal conversion layer 200 is tightly sandwiched between the upper and lower insulating substrates, forming a sealed sandwich structure together with the two polymer films of the insulating composite substrate 100. This design completely isolates the electrothermal conversion layer 200 from the electrolyte 120 and the current collector layer 400 at the electrical level, preventing interference between the heating circuit and the charging / discharging circuit, and also preventing chemical corrosion of the electrothermal conversion layer by the electrolyte.

[0047] Electrothermal conversion layer and electrode structure: The electrothermal conversion layer 200 is located inside the insulating composite substrate 100, and its overall outline is perfectly matched with the external dimensions of the insulating composite substrate 100, ensuring uniform heating of the entire electrode area; a pair of electrodes 300 are disposed at the ends of the electrothermal conversion layer 200, forming a reliable metallurgical connection with the electrothermal conversion layer 200; the lead ends of the electrodes 300 are led out through the side of the insulating composite substrate 100 and welded and fixed to the heating tab inside the battery; finally, the heating tab is led out to the outside of the battery through the sealing structure on the battery casing and electrically connected to the heating control circuit of the BMS; this connection method ensures the stability of the resistance of the heating circuit and prevents local overheating due to excessive contact resistance.

[0048] In this embodiment, the electrothermal conversion layer 200 adopts a metal oxide semiconductor material scheme, specifically a mixture of fluorine-doped tin dioxide and antimony-doped tin dioxide. It is formed on the lower insulating substrate of the insulating composite substrate 100 through a vacuum coating process to form a uniform and dense conductive heating film. Its thickness is controlled between 15nm and 50nm. This thickness range is the optimal range that balances heating efficiency, light transmittance, and forming quality. Too thin a thickness will result in insufficient heating power, while too thick a thickness will increase the overall volume of the electrode and reduce the energy density. After the coating process is completed, the upper insulating substrate is covered on the heating layer, and the two insulating substrates are tightly bonded together through a hot pressing process to form a fully sealed encapsulation of the heating layer. Electrode lead-out areas are reserved at both ends of the heating layer, which are firmly electrically connected to the electrode 300 through printing, electroplating, or welding.

[0049] Stacking and Assembly Relationship: The stacking process of the cell electrode assembly is basically the same as the traditional lamination process, with differences only in the details of the electrode structure. Specifically, the separator 130 and the self-heating battery electrode are stacked alternately and continuously in a set order. After stacking to the designed number of layers, the electrode assembly stacking is terminated and the electrode assembly is bound and fixed with termination tape. Subsequently, the electrode assembly is placed in a bonding fixture and thermally bonded under certain temperature and pressure to ensure complete bonding between the layers of the separator 130 and the self-heating battery electrode, avoiding poor heat conduction caused by interlayer gaps. After bonding, the electrode assembly is encapsulated inside the housing 110, and electrolyte 120 is injected into the housing through the liquid injection port on the housing 110. The electrolyte 120 fills all the pore spaces inside the electrode assembly. After the liquid injection is completed, the liquid injection port of the housing 110 is welded and sealed, completing the assembly of the entire cell.

[0050] BMS Connection and Control Logic: The BMS battery management system 210 is the core control unit for intelligent temperature control. It is electrically connected to the electrode 300 inside the self-heating battery electrode, forming a heating control loop independent of the charging and discharging circuit. On the acquisition side, multiple temperature sensors of the temperature acquisition module are arranged at key temperature measurement points inside the cell, on the electrode surface, or in the tab area to collect the cell temperature data in real time. On the control side, the drive module is connected to the heating tab lead of the electrode 300 and can precisely adjust the current or duty cycle of the electrothermal conversion layer 200 according to the output signal of the control module, thereby achieving stepless adjustment of the heating power. The entire control logic is supported by a closed-loop feedback mechanism to ensure the accuracy and reliability of temperature control.

[0051] Example 2: Temperature control method for intelligent temperature-controlled self-heating batteries This embodiment is a temperature control method embodiment based on the above product embodiment. The BMS executes closed-loop control logic, covering all scenarios of battery operation from resting, charging to driving discharge.

[0052] System Architecture: The core hardware architecture relied upon in this embodiment is the BMS10, which consists of four parts: a temperature acquisition module, a control module, a drive module, and a host computer interaction module. The signal acquisition end of the temperature acquisition module is electrically connected to temperature sensors at multiple key temperature measurement points arranged on the battery cell, and the signal output end is connected to the IO port of the control module. The signal output end of the control module is connected to the signal input end of the drive module, and the output end of the drive module is electrically connected to the electrode 300 of the electrothermal conversion layer 200. The host computer interaction module interacts with the vehicle central control system and the mobile APP terminal through the CAN bus or other vehicle communication bus to receive remote preheating commands from users or vehicle fast charging scenario signals, and simultaneously uploads real-time temperature data of the battery.

[0053] Temperature control process: The temperature control method in this embodiment consists of the following five core steps forming a complete closed-loop control logic: Step 1: Data Acquisition and Transmission. The BMS temperature acquisition module collects real-time temperature data of the battery cells through multiple temperature sensors located at key temperature measurement points on the cells. During the acquisition process, all temperature sensors synchronously collect data at a frequency of 1 time per second, and then transmit the data to the BMS control module via signal cables. The temperature sensors are NTC thermistors or PT100 platinum resistance thermometers, with a temperature measurement range of -40℃ to 120℃ and a measurement accuracy of ±0.1℃. The acquired temperature data is converted from analog to digital signals by the AD conversion module of the control module before subsequent calculations are performed.

[0054] Step Two: Logical Judgment and Decision-Making. The control module's built-in storage unit contains multiple preset temperature threshold ranges, including heating start-up temperature threshold, heating stop temperature threshold, optimal operating temperature range, and extreme cold environment temperature threshold. After filtering, the digital temperature data is sent to the PID calculation module, which compares it with the preset temperature threshold ranges to calculate the temperature deviation, temperature change rate, and target heating power. Subsequently, based on the calculation results, the control module issues corresponding control commands, and the drive module adjusts the heating power of the electrothermal conversion layer 200 according to the commands.

[0055] Step 3: Low-temperature preheating. When the cell temperature is lower than the preset heating start-up temperature threshold, the BMS will activate the heating circuit and start the electrothermal conversion layer 200 to heat the cells evenly at the set power. During the heating process, the BMS will continuously collect the cell temperature data and perform closed-loop adjustment of the heating power to ensure that the temperature of each area inside the cell rises synchronously. If the user's charging command has been issued at this time, the charging circuit will be in standby mode and will not perform high-current charging.

[0056] Step 4: Temperature Control Switching and Dynamic Maintenance. When the cell temperature rises to near the upper limit of the optimal operating temperature range, the BMS control module will gradually reduce the heating power to allow the cell temperature to gradually enter and stabilize within the optimal range. If the cell temperature drops below the lower limit of the optimal range after heating is stopped, the BMS will reconnect the heating circuit to supplement heating with lower power to maintain the dynamic stability of the cell temperature.

[0057] Step 5: Preheating before fast charging. When a user schedules fast charging through the vehicle's infotainment system or mobile app, or when the vehicle's navigation system detects a fast charging scenario at a charging station, the BMS will automatically activate the heating circuit in advance to preheat the battery cells to the specified temperature or above. After preheating, the BMS will send a fast charging permission signal to the vehicle's charging control system, at which point the charging control system will initiate the high-current fast charging. During fast charging, the BMS will continuously collect battery cell temperature data and dynamically adjust the heating power based on the actual charging current and ambient temperature to ensure that the battery cell temperature remains within the optimal range for fast charging.

[0058] Verification by measured data: To verify the technical effect of this embodiment, the inventors conducted multi-condition measured verification on the sample in a laboratory environment. The ambient temperature was set to the industry standard of -20℃ and -40℃, two extremely cold temperature conditions. The measured data and the corresponding calculation results confirmed the effectiveness of the technical solution. Specifically, in an extremely cold environment of -40℃, preheating a single battery cell from -40℃ to 0℃ takes only 45 seconds, with the preheating power consumption not exceeding 5% of the single cell's capacity. In an extremely cold environment of -20℃, preheating to room temperature takes only 3 minutes, a significantly shorter time than batteries using traditional external heating methods. Simultaneously, during the heating process, the maximum overall temperature difference inside the cell is only 2.8℃, completely controlled within the design threshold of 3℃. In an environment of -20℃, during continuous discharge at a 1C rate, the BMS dynamically adjusts the heating power to maintain the cell temperature within the range of 20℃±2℃. In fast charging scenarios, when the cell temperature is preheated to around 20℃, the charging power can reach over 80% of that under normal temperature conditions, and the time to charge from 20% to 97% only increases by 3 minutes compared to normal temperature conditions. Under the same conditions, batteries using traditional external heating methods require more than three times the preheating time of this embodiment, and the charging power recovery level is only about 50% of that of this embodiment.

[0059] Example 3: Alternative Variation Example The structure of this embodiment is basically the same as that of Embodiment 1 and the temperature control logic of Embodiment 2. The core difference lies in the material selection and process scheme of the electrothermal conversion layer 200, which is adapted to different application scenarios.

[0060] In this embodiment, the electrothermal conversion layer 200 adopts a carbon-based material scheme, specifically a mixed conductive paste of graphene and carbon nanotubes. Graphene serves as the primary conductive heating medium, providing stable heating efficiency; carbon nanotubes act as an auxiliary conductive medium, forming a conductive network between the graphene sheets and improving the conductivity uniformity of the heating layer. This mixed material is formed on the lower insulating substrate of the insulating composite substrate 100 through precision printing or coating processes, followed by a low-temperature sintering process to solidify the heating layer. After sintering, the upper insulating substrate is then placed on top of the heating layer, and a sealed sandwich structure is formed through a hot-pressing process. This process has a lower forming cost than vacuum coating, allows for higher precision control of the overall thickness, and further improves the contact reliability between the conductive electrodes and the heating layer.

[0061] In addition, in other alternative modifications, the electrothermal conversion layer 200 can also be made of metal alloy materials or conductive polymer materials; among them, the metal alloy material option is aluminum foil, copper foil or other alloy foil sheets, which are processed into a mesh by etching or other processes to increase its flexibility and heat dissipation area; the conductive polymer material option is polypyrrole, polyaniline or other similar materials, which are mixed with appropriate organic solvents to form a conductive paste, and then formed on the insulating composite substrate 100 by printing or coating processes; these options can all achieve the technical effects of the present invention, and have higher process adaptability.

[0062] Example 4: Alternative Variation Example The structure of this embodiment is basically the same as that of Embodiment 1 and the temperature control logic of Embodiment 2. The core difference is that the temperature control strategy of the BMS is further optimized. It adds a dual adaptive adjustment mechanism of ambient temperature sensing and battery internal resistance compensation, which further reduces heating energy consumption and improves temperature uniformity under extreme conditions.

[0063] Specifically, this embodiment of the BMS adds the following optimization logic to the original strategy: First, an ambient temperature sensing mechanism. The BMS collects ambient temperature data in real time through ambient temperature sensors placed outside the battery pack and adjusts the rate of increase of heating power based on the ambient temperature data. For example, when the ambient temperature is below -30℃, the BMS controls the heating power to increase gradually in stages to avoid excessive local temperature differences inside the battery cell due to excessive heating power. Second, a battery internal resistance compensation mechanism. The BMS collects the charging and discharging current of the battery in real time and calculates the real-time internal resistance of the battery through the voltage acquisition module. Based on the change in internal resistance, the heating power is dynamically adjusted to compensate for temperature changes caused by heat fluctuations due to battery internal resistance. Third, a multi-parameter collaborative adjustment logic. The ambient temperature, battery internal resistance, and battery cell temperature are comprehensively calculated to obtain the optimal heating power output value. This optimization scheme further reduces the power consumption of low-temperature preheating by nearly 20%, while controlling the overall temperature difference inside the battery cell within 2℃, further improving the temperature uniformity under extreme conditions and the battery's low-temperature endurance.

[0064] Comparison of the technical effects of the above embodiments To intuitively verify the technical advantages of the present invention, the table below compares the four embodiments of the present invention with three prior art solutions in terms of core performance indicators. Among them, Comparative Example 1 is a common power battery product that uses a traditional resistance heating wire for external heating, Comparative Example 2 is a product that uses a heating film to cover the surface of the cell for internal heating, and Comparative Example 3 is a low-temperature lithium battery product that uses shape memory effect to control the on / off of the heating circuit. All data are from the inventor's actual measurement data and publicly available technical testing results in the industry.

[0065] Heating method Internal surface heating Internal surface heating Internal surface heating Internal surface heating External heating wire heating Internal heating diaphragm heating Internal shape memory heating element Heating rate (°C / min) 60 60 58 62 1 15 20 Time taken to preheat from -40℃ to 0℃ (s) 45 45 48 42 1200 180 120 Preheating power consumption (%) <5 <5 <5.5 <4.2 >2 >8 >6 Temperature difference inside the battery cell (°C) ≤3 ≤3 ≤3 ≤2 ≥10 ≥5 ≥8 Heating energy utilization rate (%) 90 90 88 92 20 60 70 Low-temperature charging power recovery rate (%) 80 80 78 85 30 60 50 The percentage increase in battery volume due to the heating system (%) <2 <2 <2.5 <2 >10 >5 >3 thermal runaway safety risks Extremely low Extremely low Extremely low Extremely low Low middle high Note: The test conditions for the above measured data were: ambient temperature -20℃ / -40℃, battery capacity 100Ah, charging rate 1C, and discharging rate 1C. The low-temperature charging power recovery ratio refers to the ratio of the charging power after preheating at -20℃ to the charging power at room temperature. Heating energy utilization rate refers to the proportion of heat used to raise the temperature of the battery cell during the heating process to the total electrical energy consumed; The data for Comparative Examples 1-3 are from publicly available technical documents and measured data from mass-produced products.

[0066] As can be seen from the data in the table, the four embodiments of the present invention are significantly superior to the comparative embodiments of the prior art in terms of core performance indicators such as heating rate, preheating time, preheating power consumption, cell temperature uniformity, heating energy utilization rate, low-temperature charging power recovery ratio, and the impact of the heating system on battery volume. This performance difference fully verifies the technical advantages of the present invention and can fully meet the usage requirements of new energy vehicles and energy storage power stations in cold environments.

[0067] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of those different embodiments or examples.

[0068] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0069] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various variations or substitutions within the technical scope disclosed in the present invention, and these should all be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A smart temperature-controlled self-heating battery, characterized in that, include: A battery cell and a battery management system (BMS), wherein the battery cell includes self-heating battery electrodes, a separator, an electrolyte, and a casing; The separator and the self-heating battery electrode are continuously and alternately stacked, bonded and fixed together to form an integral structure and encapsulated inside the shell; the electrolyte fills the inside of the shell. The self-heating battery electrode includes: An insulating composite substrate formed by hot-pressing at least two layers of polymer film; An electrothermal conversion layer is disposed inside the insulating composite substrate, and the electrothermal conversion layer is used to generate heat when energized; At least one pair of electrodes forms an electrical connection with the electrothermal conversion layer; Current collector layer and electrode active material layer disposed on the first surface of the insulating composite substrate; A current collector layer and an electrode active material layer are disposed on the second surface of the insulating composite substrate; The BMS battery management system is electrically connected to the electrodes in the self-heating battery electrode sheet, and is used to control the start / stop of the electrothermal conversion layer and the heating power according to the real-time temperature of the battery cell.

2. The intelligent temperature-controlled self-heating battery according to claim 1, characterized in that, The BMS battery management system includes a temperature acquisition module for acquiring temperature data inside the cell, on the electrode surface, or in the tab area.

3. The intelligent temperature-controlled self-heating battery according to claim 1, characterized in that, The BMS battery management system is equipped with a low-temperature preheating strategy, a target temperature control strategy, and a fast-charging preheating strategy. The low-temperature preheating strategy is as follows: when the detected temperature is lower than the set temperature, the electrothermal conversion layer is automatically activated to perform uniform preheating. The target temperature control strategy is as follows: when the cell temperature reaches the preset temperature range, reduce the heating power or stop heating. The fast charging preheating strategy is to automatically preheat the battery cells to a specified temperature or above before the fast charging command is initiated.

4. The intelligent temperature-controlled self-heating battery according to claim 1, characterized in that, The electrothermal conversion layer is at least one metal oxide semiconductor material selected from fluorine-doped tin dioxide, antimony-doped tin dioxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, vanadium pentoxide, indium zinc oxide, molybdenum-doped indium oxide, and indium tin oxide. It is prepared as a conductive heating film on the insulating composite substrate by vacuum deposition process. The thickness of the electrothermal conversion layer is 15nm~50nm. The electrode is disposed on the electrothermal conversion layer and electrically connected to the electrothermal conversion layer, and the electrode is connected to the power supply.

5. The intelligent temperature-controlled self-heating battery according to claim 1, characterized in that, The electrothermal conversion layer is one or more of graphene, carbon nanotubes, metal alloys, or conductive polymers, and is prepared as a conductive heating film on the composite substrate by physical vapor deposition, printing, or coating processes; the electrode is disposed on the electrothermal conversion layer and electrically connected to the electrothermal conversion layer, and the electrode is connected to a power supply.

6. The intelligent temperature-controlled self-heating battery according to claim 1, characterized in that, The power supply for the electrothermal conversion layer is a low-voltage DC power supply, which is powered by the battery cell itself or an external auxiliary power supply; and the self-heating function and the charging and discharging function are independent of each other and do not interfere with each other.

7. The intelligent temperature-controlled self-heating battery according to claim 1, characterized in that, The electrothermal conversion layer has PTC self-limiting temperature characteristics. When the temperature of the electrothermal conversion layer rises to the critical temperature, its resistance value will increase sharply, automatically limiting the heating power so that the maximum heating temperature of the battery cell does not exceed the set temperature threshold.

8. The intelligent temperature-controlled self-heating battery according to claim 1, characterized in that, The intelligent temperature-controlled self-heating battery has a minimum operating temperature of less than -40℃ and is highly adaptable to cold environments.

9. The intelligent temperature-controlled self-heating battery according to claim 1, characterized in that, When the electrothermal conversion layer is in operation, the overall temperature difference inside the battery cell is less than or equal to 3°C, and the temperature uniformity is excellent.

10. The intelligent temperature-controlled self-heating battery according to claim 1, characterized in that, The current collector layer on the first surface of the insulating composite substrate is a positive current collector layer, and the corresponding active material layer is a positive active material layer; the current collector layer on the second surface of the insulating composite substrate is a negative current collector layer, and the corresponding active material layer is a negative active material layer. Alternatively, the current collector layer on the first surface of the insulating composite substrate is a positive electrode current collector layer, and the corresponding active material layer is a positive electrode active material layer; the current collector layer on the second surface of the insulating composite substrate is also a positive electrode current collector layer, and the corresponding active material layer is a positive electrode active material layer. Alternatively, the current collector layer on the first surface of the insulating composite substrate is a negative electrode current collector layer, and the corresponding active material layer is a negative electrode active material layer; the current collector layer on the second surface of the insulating composite substrate is also a negative electrode current collector layer, and the corresponding active material layer is a negative electrode active material layer.

11. A temperature control method for an intelligent temperature-controlled self-heating battery, characterized in that, Based on the intelligent temperature-controlled self-heating battery according to any one of claims 1-10, the following steps are included: (1) The BMS battery management system collects cell temperature data in real time; (2) Determine whether the cell temperature is lower than the preset preheating threshold; (3) If the temperature is below the preset preheating threshold, power is supplied to the electrothermal conversion layer in the self-heating battery electrode to make the multilayer composite electrode heat up uniformly. (4) When the cell temperature enters the preset optimal operating range, reduce or cut off the power supply to the electrothermal conversion layer; (5) During the charging and discharging process of the battery, the heating power of the electrothermal conversion layer is dynamically adjusted to maintain the cell temperature within the optimal operating range.

12. The temperature control method for the intelligent temperature-controlled self-heating battery according to claim 11, characterized in that, In low-temperature environments ranging from -40℃ to 0℃, the preheating time of the intelligent temperature-controlled self-heating battery does not exceed the set time, which can quickly meet the conditions for fast charging and high-current discharge.

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