High temperature tolerant battery system for powering oil drilling logging equipment and control method

Abstract

The application discloses a high-temperature-resistant battery system and a control method for power supply of a petroleum drilling logging device, and relates to the technical field of battery systems. The system comprises a packaging unit, a high-temperature-resistant battery cell unit and a protection circuit unit. The packaging unit comprises a multilayer composite shell and a plurality of independent cabin bodies arranged in the shell, and the independent cabin bodies are filled with graded phase change materials. The high-temperature-resistant battery cell unit comprises a plurality of high-temperature-resistant battery cells. The protection circuit unit comprises a microcontroller and a wide-bandgap semiconductor power device. The microcontroller is configured to dynamically adjust the on-off state of the wide-bandgap semiconductor power device according to a current operation stage and real-time temperature data, so as to adjust the discharge parameters of the high-temperature-resistant battery cell unit and match the heat generation rate of the high-temperature-resistant battery cells with the heat absorption rate of the graded phase change materials. The system realizes a transition from passive thermal insulation to active thermal matching, reduces the temperature fluctuation amplitude of the battery cells, and effectively solves the problems of high-temperature failure and low energy utilization rate of traditional downhole batteries.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a high-temperature resistant battery system and control method for powering oil drilling logging equipment. Background Technology

[0002] In oil drilling, especially in deep and ultra-deep well operations, logging-while-drilling (LWD) and measurement-while-drilling (MWD) systems require stable and reliable downhole power. Traditional lithium batteries are prone to problems such as SEI film decomposition, electrolyte vaporization, and separator shrinkage in environments exceeding 150°C, leading to a sharp drop in capacity or even thermal runaway. Existing high-temperature resistant battery solutions mostly employ simple physical insulation or rely on a single high-temperature resistant material, resulting in large size and an inability to dynamically adjust the discharge strategy according to downhole conditions. Furthermore, it is difficult to balance the contradiction between environmental high-temperature resistance and resistance to self-generated heat within a limited space. Summary of the Invention

[0003] This application provides a high-temperature resistant battery system and control method for powering oil drilling logging equipment, in order to solve the technical problem of balancing the contradiction between environmental high temperature resistance and self-heat generation resistance in a limited space.

[0004] In a first aspect, this application provides a high-temperature resistant battery system for powering oil drilling logging equipment, comprising a packaging unit, a high-temperature resistant battery cell unit, and a protection circuit unit; the packaging unit includes a multi-layer composite shell and multiple independent chambers disposed inside the shell, the multi-layer composite shell including a pressure-bearing layer, a vacuum insulation layer, and a temperature-equalizing layer arranged sequentially from the outside to the inside, and the independent chambers being filled with a graded phase change material; the high-temperature resistant battery cell unit includes multiple high-temperature resistant batteries using an ionic liquid gel electrolyte and a ceramic separator, the batteries being disposed within the independent chambers; the protection circuit unit is electrically connected to the high-temperature resistant battery cell unit and includes a microcontroller and a wide bandgap semiconductor power device, the microcontroller being configured as follows: The current operation stage is identified based on downhole sensor data, and the on / off state of the wide bandgap semiconductor power device is dynamically adjusted based on the identification results and real-time temperature data to regulate the discharge parameters of the high-temperature resistant battery cell unit and match the heat generation rate of the high-temperature resistant battery cell with the heat absorption rate of the graded phase change material.

[0005] In some embodiments, the graded phase change material includes low-melting-point phase change microcapsules and a high-melting-point phase change material matrix, wherein the low-melting-point phase change microcapsules are dispersed in the high-melting-point phase change material matrix.

[0006] In some embodiments, the microcontroller has a built-in heat generation rate model. The heat generation rate model calculates the instantaneous heat generation rate of the high-temperature resistant battery cell based on the real-time discharge current, internal resistance, and temperature change rate of the high-temperature resistant battery cell, and compares the instantaneous heat generation rate with a preset heat absorption rate threshold of the graded phase change material as a basis for adjusting the discharge parameters.

[0007] In some of these embodiments, the microcontroller is specifically configured as follows: When the real-time temperature data reaches the first temperature threshold, the thermal matching mode is entered; In the thermal matching mode, the microcontroller generates a power reduction curve based on the expected power consumption requirements of the current operating stage and the remaining heat absorption capacity of the graded phase change material. By adjusting the duty cycle of the wide bandgap semiconductor power switch array, the actual discharge power of the high-temperature resistant battery cell decreases along the power reduction curve.

[0008] In some embodiments, a phase change material temperature sensor is provided on the inner wall of the independent chamber to monitor the real-time temperature of the graded phase change material. The microcontroller calculates the remaining heat absorption capacity of the graded phase change material based on the difference between the real-time temperature and the phase change temperature, and the remaining heat absorption capacity is the remaining heat absorption capacity of the low-melting-point phase change capsule in the graded phase change material.

[0009] In some embodiments, the protection circuit unit further includes a hardware protection subunit and a high-temperature reference source. The hardware protection subunit is connected to the control terminal of the wide bandgap semiconductor power device. The hardware protection subunit is configured to trigger the wide bandgap semiconductor power device to perform a lockout protection action before the microcontroller intervenes when the battery terminal voltage or charging / discharging current of the high-temperature resistant cell unit exceeds the safety threshold set by the high-temperature reference source.

[0010] In some embodiments, the protection circuit unit further includes a digital potentiometer connected to the microcontroller and connected in series between the high-temperature reference source and the hardware protection subunit; the microcontroller sends a threshold adjustment signal to the digital potentiometer according to the current operating stage or the real-time temperature data to dynamically change the protection action trigger point of the hardware protection subunit.

[0011] Secondly, this application also provides a control method for a high-temperature resistant battery system as described in the first aspect, comprising the following steps: Acquire downhole sensor data and battery status data, and identify the current drilling operation stage based on the downhole sensor data. The battery status data includes cell temperature data and phase change material temperature data. Based on the current operating stage and the cell temperature data, determine whether to enter thermal matching mode; If it is determined that the thermal matching mode will not be entered, the corresponding discharge parameters will be retrieved according to the current operation stage, and normal discharge scheduling will be performed. If it is determined that the thermal matching mode has been entered, the remaining heat absorption capacity of the graded phase change material is calculated based on the cell temperature data and the phase change material temperature data. A power reduction curve is generated based on the remaining heat absorption capacity, and the discharge power is dynamically adjusted along the power reduction curve.

[0012] In some embodiments, determining whether to enter thermal matching mode based on the current operating stage and the cell temperature data includes: Compare the cell temperature data with a preset temperature threshold. If the cell temperature data is lower than the preset temperature threshold, the thermal matching mode will not be entered. If the cell temperature data is not lower than the preset temperature threshold, the rate of change of the cell temperature data is calculated, and if the rate of change exceeds the preset change threshold, the thermal matching mode is entered.

[0013] In some embodiments, generating a power reduction curve based on the remaining heat absorption capacity includes: Calculate the maximum permissible average heat production rate based on the remaining heat absorption capacity and the estimated remaining time of the current operation phase; The maximum allowable discharge current is determined based on the maximum permissible average heat generation rate and the current cell internal resistance. By progressively limiting the discharge current of the high-temperature resistant battery cell below the maximum allowable discharge current, a current-power curve is generated, resulting in the power reduction curve.

[0014] Compared with the prior art, this application has the following beneficial effects: Through the multi-layer composite shell of the encapsulation unit, the pressure-bearing layer withstands the downhole high pressure, the vacuum insulation layer blocks external heat conduction, and the temperature equalization layer balances the internal temperature, creating a stable thermal environment for the battery cell. The staged phase change material in the independent compartment absorbs the heat generated by the battery cell through multiple staged phase change temperature points. The high-temperature resistant battery cell unit uses ionic liquid gel electrolyte and ceramic diaphragm to fundamentally solve the problems of electrolyte evaporation and diaphragm shrinkage at high temperatures. The microcontroller of the protection circuit unit receives downhole sensor data in real time, intelligently identifies the operation stages such as drilling, drilling, and tripping, and dynamically adjusts the on / off state of wide bandgap semiconductor power devices according to the real-time temperature, so that the heat generation rate of the battery cell is dynamically matched with the heat absorption rate of the staged phase change material. This achieves a leap from passive heat insulation to active thermal matching, reduces the temperature fluctuation range of the battery cell, and can work stably and continuously in high-temperature environments of 180℃~220℃, extending the single downhole operation time and effectively solving the problems of high-temperature failure and low energy utilization of traditional downhole batteries. Attached Figure Description

[0015] Figure 1 This is a structural block diagram of a high-temperature resistant battery system for powering oil drilling logging equipment, as shown in an embodiment of this application. Figure 2 This is a schematic flowchart illustrating the control method of a high-temperature resistant battery system according to an embodiment of this application. Detailed Implementation

[0016] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0017] Please refer to Figure 1 , Figure 1 This application provides a structural block diagram of a high-temperature resistant battery system for powering oil drilling logging equipment. The high-temperature resistant battery system for powering oil drilling logging equipment in this embodiment includes a packaging unit 1, a high-temperature resistant battery cell unit 2, and a protection circuit unit 3. The packaging unit 1 includes a multi-layer composite shell and multiple independent chambers disposed inside the shell. The multi-layer composite shell includes a pressure-bearing layer, a vacuum insulation layer and a temperature equalization layer arranged sequentially from the outside to the inside. The independent chambers are filled with graded phase change material. The high-temperature resistant battery cell unit 2 includes multiple high-temperature resistant battery cells using ionic liquid gel electrolyte and ceramic membrane, and the battery cells are disposed in the independent compartment. The protection circuit unit 3 is electrically connected to the high-temperature resistant battery cell unit 2, and includes a microcontroller and a wide bandgap semiconductor power device. The microcontroller is configured as follows: The current operation stage is identified based on downhole sensor data, and the on / off state of the wide bandgap semiconductor power device is dynamically adjusted based on the identification results and real-time temperature data to regulate the discharge parameters of the high-temperature resistant battery cell unit and match the heat generation rate of the high-temperature resistant battery cell with the heat absorption rate of the graded phase change material.

[0018] In this embodiment, the encapsulation unit 1 forms a multi-layer composite shell consisting of a pressure-bearing layer, a vacuum insulation layer, and a temperature equalization layer arranged sequentially from the outside to the inside. The pressure-bearing layer resists the impact of high pressure downhole, the vacuum insulation layer blocks the conduction of external high temperature to the inside, and the temperature equalization layer ensures a uniform internal temperature field. At the same time, the graded phase change material filled in the independent compartment absorbs the heat generated by the battery cell in stages using its multi-stage phase change characteristics.

[0019] The high-temperature resistant cell unit 2 employs an ionic liquid gel electrolyte and a ceramic separator, fundamentally addressing the short-circuit failure issues caused by electrolyte evaporation and separator shrinkage at high temperatures. The all-ceramic separator can be a three-dimensional network structure composed of boron nitride nanosheets and zirconium oxide fibers, with a thickness of 80–120 μm, a porosity of 45%–60%, and an ionic conductivity of [missing value] at 200℃. The ionic liquid quasi-solid electrolyte can use [EMIm][TFSI] ionic liquid as the electrolyte and PVDF-HFP as the gel framework; the positive electrode material of the high-temperature resistant battery cell can be... Covered The negative electrode material is a composite material of lithium titanate and hard carbon.

[0020] The microcontroller in protection circuit unit 3 receives downhole sensor data in real time, intelligently identifies different operational stages such as drilling, drilling progress, and tripping out, and dynamically adjusts the on / off state of the wide-bandgap semiconductor power devices based on the identification results and real-time temperature data. This precisely controls the discharge parameters, enabling dynamic matching between the heat generation rate of the battery cell and the heat absorption rate of the staged phase change material. The wide-bandgap semiconductor power devices can be SiC MOSFETs or GaN HEMTs, with a working junction temperature up to 200℃ and a temperature-dependent on-resistance change rate of <20%, solving the problems of high-temperature leakage current and threshold voltage drift in traditional silicon devices.

[0021] This embodiment reduces cell temperature fluctuation by more than 60% through the synergistic effect of passive heat insulation, intrinsic temperature resistance, and active thermal matching. It can operate stably in high-temperature environments of 180℃ to 220℃, extending the single downhole operation time by 30% to 50% and the cell cycle life by more than 2 times. At the same time, wide-bandgap semiconductor devices ensure protection actions are performed with microsecond-level response at high temperatures, realizing a technological leap from passive power supply to intelligent energy management for downhole batteries.

[0022] In some embodiments, the hierarchical phase change material includes low-melting-point phase change microcapsules and a high-melting-point phase change material matrix, wherein the low-melting-point phase change microcapsules are dispersed in the high-melting-point phase change material matrix.

[0023] In this embodiment, addressing the issue of a single phase change material having a constant heat absorption rate and being difficult to match with the dynamic heat generation of the battery cell, a graded phase change material structure is adopted. Low-melting-point phase change microcapsules are uniformly dispersed within a high-melting-point phase change material matrix. As the temperature rises, the high-melting-point matrix melts first, absorbing the initial heat. When the temperature continues to rise and reaches the melting point of the microcapsules, a large number of microcapsules melt simultaneously, absorbing the peak heat, thus achieving a graded response in heat absorption. Through this two-stage phase change synergy, the heat absorption efficiency is improved by more than 40%, and the peak heat generation of the battery cell is effectively reduced. This provides a precise physical basis for the microcontroller to calculate the remaining heat absorption capacity and formulate power reduction strategies, significantly enhancing the system's thermal matching capability.

[0024] In some embodiments, the microcontroller has a built-in heat generation rate model. The heat generation rate model calculates the instantaneous heat generation rate of the high-temperature resistant battery cell based on the real-time discharge current, internal resistance, and temperature change rate of the high-temperature resistant battery cell, and compares the instantaneous heat generation rate with a preset heat absorption rate threshold of the graded phase change material as a basis for adjusting the discharge parameters.

[0025] In this embodiment, addressing the issues of traditional batteries' inability to dynamically sense their own heat generation and their difficulty in coordinating with phase change materials, a microcontroller with a built-in heat generation rate model is implemented. Using this pre-built heat generation rate model, the microcontroller calculates the instantaneous heat generation rate of the battery cell based on real-time data collection of discharge current, cell internal resistance, and temperature change rate. This rate is then compared in real-time with a preset heat absorption rate threshold for the graded phase change material. The comparison result serves as the basis for dynamically adjusting discharge parameters. This achieves quantitative sensing of the relationship between heat generation and absorption, enabling precise control of discharge scheduling and ensuring that the heat generation of the battery cell never exceeds the heat absorption capacity of the phase change material.

[0026] In some embodiments, the microcontroller is specifically configured as follows: When the real-time temperature data reaches the first temperature threshold, the thermal matching mode is entered; In the thermal matching mode, the microcontroller generates a power reduction curve based on the expected power consumption requirements of the current operating stage and the remaining heat absorption capacity of the graded phase change material. By adjusting the duty cycle of the wide bandgap semiconductor power switch array, the actual discharge power of the high-temperature resistant battery cell decreases along the power reduction curve.

[0027] In this embodiment, to address the issues of delayed response and easy triggering of hard shutdown in conventional overheat protection, an active thermal matching mode is implemented. When the real-time temperature reaches a first threshold, the microcontroller enters the thermal matching mode. Based on the expected power consumption requirements of the current operation stage and the remaining heat absorption capacity calculated from the graded phase change material, a power reduction curve is dynamically generated. By precisely adjusting the duty cycle of the wide-bandgap semiconductor power switch array, the actual discharge power is smoothly reduced along this curve. This transforms passive over-limit protection into active power reduction matching, maintaining a minimum power supply while ensuring safety, avoiding operation interruptions, and thus achieving refined and proactive thermal safety control.

[0028] In some embodiments, a phase change material temperature sensor is provided on the inner wall of the independent chamber to monitor the real-time temperature of the graded phase change material. The microcontroller calculates the remaining heat absorption capacity of the graded phase change material based on the difference between the real-time temperature and the phase change temperature, and the remaining heat absorption capacity is the remaining heat absorption capacity of the low-melting-point phase change capsule in the graded phase change material.

[0029] In this embodiment, to address the difficulty in quantifying the remaining heat absorption capacity of the staged phase material in real time, a phase change material temperature sensor is installed on the inner wall of the chamber. The sensor monitors the temperature of the staged phase change material in real time. The microcontroller accurately calculates the current remaining heat absorption capacity based on the difference between the measured temperature and the material's phase change temperature, with a particular focus on the remaining capacity of the low-melting-point phase change capsules (as they play a crucial role in heat absorption during the high-temperature peak period). This achieves real-time quantitative sensing of the phase change material's thermal buffering capacity, enabling the microcontroller to accurately grasp the thermal management margin, providing reliable data support for generating the power reduction curve, and ensuring the scientific and real-time nature of thermal matching decisions.

[0030] In some embodiments, the protection circuit unit 3 further includes a hardware protection subunit and a high-temperature reference source. The hardware protection subunit is connected to the control terminal of the wide bandgap semiconductor power device. The hardware protection subunit is configured to trigger the wide bandgap semiconductor power device to perform a lockout protection action before the microcontroller intervenes when the battery terminal voltage or charging / discharging current of the high-temperature resistant cell unit exceeds the safety threshold set by the high-temperature reference source.

[0031] In this embodiment, to address the risks of response delay and potential failure under extreme transient faults associated with pure software protection, an independent hardware-level protection channel is implemented. The hardware protection subunit directly monitors the battery terminal voltage and charging / discharging current, comparing them in real-time with a precise reference voltage provided by a high-temperature reference source (such as the LT6657, operating at 175°C). Once the parameters exceed the safety threshold, the hardware logic circuit, without microcontroller intervention, triggers wide-bandgap semiconductor power devices at the nanosecond level to execute latch-up protection, forcibly cutting off the main circuit. This embodiment constructs a dual safety redundancy combining software algorithms and hardware circuits. The hardware channel responds faster than the software, ensuring reliable system shutdown even in scenarios such as microcontroller crashes, program errors, or extreme transient short circuits, significantly improving the intrinsic safety level.

[0032] In some embodiments, the protection circuit unit 3 further includes a digital potentiometer, which is connected to the microcontroller and connected in series between the high-temperature reference source and the hardware protection subunit. The microcontroller sends a threshold adjustment signal to the digital potentiometer according to the current operating stage or the real-time temperature data to dynamically change the protection action trigger point of the hardware protection subunit.

[0033] In this embodiment, to address the issue that fixed hardware protection thresholds cannot adapt to complex downhole operating conditions, a digital potentiometer (such as the AD5254-HT) is introduced into the hardware protection channel. The digital potentiometer is connected in series between the high-temperature reference source and the hardware protection subunit. The microcontroller sends a threshold adjustment signal to the digital potentiometer based on the current operating stage (low-power drilling stage or high-power drilling stage) and real-time temperature data, dynamically changing the voltage division ratio to adjust the voltage and current trigger points of the hardware protection in real time. This embodiment achieves a fusion of hardware-level response speed and software-level flexible configuration, preserving the reliability of the nanosecond-level response of the hardware protection while allowing the protection threshold to adaptively optimize according to operating conditions, avoiding false protection or protection lag caused by fixed thresholds.

[0034] See Figure 2 , Figure 2 This diagram illustrates a control method for a high-temperature resistant battery system according to this application. The control method for the high-temperature resistant battery system in this embodiment includes steps S101 to S104, which are detailed below: Step S101: Acquire downhole sensor data and battery status data, and identify the current drilling operation stage based on the downhole sensor data. The battery status data includes cell temperature data and phase change material temperature data. Step S102: Based on the current operating stage and the cell temperature data, determine whether to enter the thermal matching mode; Step S103: If it is determined that the thermal matching mode will not be entered, the corresponding discharge parameters are retrieved according to the current operation stage, and conventional discharge scheduling is performed. Step S104: If it is determined that the thermal matching mode has been entered, the remaining heat absorption capacity of the graded phase change material is calculated based on the cell temperature data and the phase change material temperature data. A power reduction curve is generated based on the remaining heat absorption capacity, and the discharge power is dynamically adjusted along the power reduction curve.

[0035] In this embodiment, traditional downhole battery systems cannot dynamically adjust their discharge strategies based on real-time operating conditions and their own thermal state, leading to a high risk of thermal runaway or low energy utilization. This embodiment sets up a closed-loop control process for sensing, decision-making, and execution.

[0036] Step S101 acquires downhole sensor data (such as depth and vibration) and battery status data (including cell temperature and phase change material temperature), and intelligently identifies the current drilling operation stage (downhole, drilling, tripping, etc.) based on the sensor data, providing a scenario basis for subsequent differentiated scheduling; Step S102 comprehensively determines whether to enter the thermal matching mode based on the identified operation stage and cell temperature data. This determination not only considers the absolute temperature value, but also implicitly assesses the temperature rise trend and operation power consumption requirements; If it is determined that the thermal matching mode should not be entered, then step S103 is executed, and the preset discharge parameters are retrieved according to the operation stage for normal discharge scheduling to ensure normal operation efficiency; If it is determined that the thermal matching mode is entered, then step S104 is executed, and the remaining heat absorption capacity of the staged phase change material is accurately calculated based on the cell temperature and phase change material temperature, and a power reduction curve is generated based on this, and the actual discharge power is dynamically adjusted along the curve.

[0037] This embodiment achieves a leap from single-mode discharge to condition-adaptive thermal matching, thereby prioritizing operational efficiency when there is sufficient safety margin and actively and smoothly reducing power when the thermal load is close to the limit. This avoids operational interruptions caused by hard shutdown triggered by overheating and maximizes the thermal buffering capacity of phase change materials. The time for a single well operation is extended by more than 30%, and the cell temperature fluctuation is reduced by 50%, truly realizing intelligent energy management of the downhole battery system.

[0038] In some embodiments, determining whether to enter thermal matching mode based on the current operating stage and the cell temperature data includes: Compare the cell temperature data with a preset temperature threshold. If the cell temperature data is lower than the preset temperature threshold, the thermal matching mode will not be entered. If the cell temperature data is not lower than the preset temperature threshold, the rate of change of the cell temperature data is calculated, and if the rate of change exceeds the preset change threshold, the thermal matching mode is entered.

[0039] In this embodiment, to address the issue that relying on a single temperature threshold can easily lead to false triggering or delayed activation of the thermal matching mode, this embodiment compares the cell temperature with a preset threshold. If the temperature is below the threshold, it is considered safe, and thermal matching is not initiated. If the temperature reaches or exceeds the threshold, the temperature change rate is further calculated. Only when the change rate also exceeds a preset change threshold is thermal matching mode initiated. This approach avoids frequent false triggering due to short-term temperature fluctuations while also accurately detecting early signs of a rapid temperature rise, enabling proactive intervention and maximizing normal operation while ensuring safety.

[0040] In some embodiments, generating a power reduction curve based on the remaining heat absorption capacity includes: Calculate the maximum permissible average heat production rate based on the remaining heat absorption capacity and the estimated remaining time of the current operation phase; The maximum allowable discharge current is determined based on the maximum permissible average heat generation rate and the current cell internal resistance. By progressively limiting the discharge current of the high-temperature resistant battery cell below the maximum allowable discharge current, a current-power curve is generated, resulting in the power reduction curve.

[0041] In this embodiment, exemplarily, based on the remaining heat absorption capacity and the estimated remaining time for the current work phase. Calculate the maximum permissible average heat production rate. ; According to the maximum permissible average heat production rate and current cell internal resistance Through the heat generation rate formula The corresponding maximum allowable discharge current curve was calculated by reverse calculation. ; The actual discharge current is gradually limited to the maximum permissible discharge current curve. The following refers to the actual discharge power. This changes dynamically, thus forming the power reduction curve.

[0042] In the several embodiments provided in this application, it will be understood that each block in the flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those shown in the figures. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved.

[0043] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0044] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above descriptions are merely specific embodiments of this application and are not intended to limit the scope of protection of this application. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application for those skilled in the art.

Claims

1. A high temperature tolerant battery system for powering oil drilling logging equipment, characterized by, The system includes a packaging unit, a high-temperature resistant battery cell unit, and a protection circuit unit. The packaging unit comprises a multi-layer composite shell and multiple independent compartments disposed within the shell. The multi-layer composite shell includes, from the outside to the inside, a pressure-bearing layer, a vacuum insulation layer, and a temperature-equalizing layer. Each independent compartment is filled with a graded phase change material. The high-temperature resistant battery cell unit comprises multiple high-temperature resistant batteries using an ionic liquid gel electrolyte and a ceramic diaphragm, and the batteries are disposed within the independent compartments. The protection circuit unit is electrically connected to the high-temperature resistant battery cell unit and includes a microcontroller and a wide-bandgap semiconductor power device. The microcontroller is configured as follows: The current operation stage is identified based on downhole sensor data, and the on / off state of the wide bandgap semiconductor power device is dynamically adjusted based on the identification results and real-time temperature data to regulate the discharge parameters of the high-temperature resistant battery cell unit and match the heat generation rate of the high-temperature resistant battery cell with the heat absorption rate of the graded phase change material.

2. The high-temperature resistant battery system for powering oil drilling logging equipment as described in claim 1, characterized in that, The graded phase change material includes low-melting-point phase change microcapsules and a high-melting-point phase change material matrix, wherein the low-melting-point phase change microcapsules are dispersed in the high-melting-point phase change material matrix.

3. The high-temperature resistant battery system for powering oil drilling logging equipment as described in claim 1, characterized in that, The microcontroller has a built-in heat generation rate model. The heat generation rate model calculates the instantaneous heat generation rate of the high-temperature resistant battery cell based on the real-time discharge current, internal resistance, and temperature change rate of the high-temperature resistant battery cell. The instantaneous heat generation rate is then compared with the preset heat absorption rate threshold of the graded phase change material to serve as the basis for adjusting the discharge parameters.

4. The high-temperature resistant battery system for powering oil drilling logging equipment as described in claim 1, characterized in that, The microcontroller is specifically configured as follows: When the real-time temperature data reaches the first temperature threshold, the thermal matching mode is entered; In the thermal matching mode, the microcontroller generates a power reduction curve based on the expected power consumption requirements of the current operating stage and the remaining heat absorption capacity of the graded phase change material. By adjusting the duty cycle of the wide bandgap semiconductor power switch array, the actual discharge power of the high-temperature resistant battery cell decreases along the power reduction curve.

5. The high-temperature resistant battery system for powering oil drilling logging equipment as described in claim 4, characterized in that, The independent chamber is equipped with a phase change material temperature sensor on its inner wall to monitor the real-time temperature of the graded phase change material. The microcontroller calculates the remaining heat absorption capacity of the graded phase change material based on the difference between the real-time temperature and the phase change temperature, and the remaining heat absorption capacity is the remaining heat absorption capacity of the low-melting-point phase change capsule in the graded phase change material.

6. The high-temperature resistant battery system for powering oil drilling logging equipment as described in claim 1, characterized in that, The protection circuit unit also includes a hardware protection subunit and a high-temperature reference source. The hardware protection subunit is connected to the control terminal of the wide bandgap semiconductor power device. The hardware protection subunit is configured to trigger the wide bandgap semiconductor power device to perform a lockout protection action before the microcontroller intervenes when the battery terminal voltage or charging / discharging current of the high-temperature resistant cell unit exceeds the safety threshold set by the high-temperature reference source.

7. The high-temperature resistant battery system for powering oil drilling logging equipment as described in claim 6, characterized in that, The protection circuit unit also includes a digital potentiometer, which is connected to the microcontroller and connected in series between the high-temperature reference source and the hardware protection subunit. The microcontroller sends a threshold adjustment signal to the digital potentiometer according to the current operating stage or the real-time temperature data to dynamically change the protection action trigger point of the hardware protection subunit.

8. A control method for a high-temperature resistant battery system as described in any one of claims 1 to 7, characterized in that, Includes the following steps: Acquire downhole sensor data and battery status data, and identify the current drilling operation stage based on the downhole sensor data. The battery status data includes cell temperature data and phase change material temperature data. Based on the current operating stage and the cell temperature data, determine whether to enter thermal matching mode; If it is determined that the thermal matching mode will not be entered, the corresponding discharge parameters will be retrieved according to the current operation stage, and normal discharge scheduling will be performed. If it is determined that the thermal matching mode has been entered, the remaining heat absorption capacity of the graded phase change material is calculated based on the cell temperature data and the phase change material temperature data. A power reduction curve is generated based on the remaining heat absorption capacity, and the discharge power is dynamically adjusted along the power reduction curve.

9. The control method for the high-temperature resistant battery system as described in claim 8, characterized in that, The step of determining whether to enter thermal matching mode based on the current operating stage and the cell temperature data includes: Compare the cell temperature data with a preset temperature threshold. If the cell temperature data is lower than the preset temperature threshold, the thermal matching mode will not be entered. If the cell temperature data is not lower than the preset temperature threshold, the rate of change of the cell temperature data is calculated, and if the rate of change exceeds the preset change threshold, the thermal matching mode is entered.

10. The control method for the high-temperature resistant battery system as described in claim 8, characterized in that, The step of generating a power reduction curve based on the remaining heat absorption capacity includes: Calculate the maximum permissible average heat production rate based on the remaining heat absorption capacity and the estimated remaining time of the current operation phase; The maximum allowable discharge current is determined based on the maximum permissible average heat generation rate and the current cell internal resistance. By progressively limiting the discharge current of the high-temperature resistant battery cell below the maximum allowable discharge current, a current-power curve is generated, resulting in the power reduction curve.

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