Temperature control method and mobile power supply

Abstract

This invention relates to the field of mobile power bank technology, and in particular to a temperature control method and a mobile power bank; it includes the following steps: identifying the current operating condition and collecting the cell temperature and PCB heat source temperature; when in charging / discharging condition, if the cell temperature is higher than a first preset threshold or the PCB heat source temperature is higher than a second preset threshold, then the current power is reduced to a power value that matches the current temperature; when in simultaneous charging and discharging condition, if the cell temperature is higher than the first preset threshold or the PCB heat source temperature is higher than a third preset threshold, then the current power is reduced to a power value that matches the current temperature; the second preset threshold is higher than the third preset threshold; this invention sets different power reduction trigger thresholds for the PCB heat source based on different operating conditions. Using a higher threshold during charging and discharging can effectively release the cell performance, while using a lower threshold during simultaneous charging and discharging can reduce the power in advance based on the PCB heat source temperature when the cell temperature rise is not significant, preventing high-temperature failure of power devices and preventing heat conduction to the casing.

Description

Technical Field

[0001] This invention relates to the field of portable power bank technology, and in particular to a temperature control method and a portable power bank. Background Technology

[0002] Currently, power banks in the industry only use single-point NTC thermistors in the battery cell area for temperature monitoring. This method uses the MCU to collect the battery cell temperature as the core basis for power management under all operating conditions. For power banks with multi-channel independent DC-DC architecture, there are usually multiple operating conditions. Under the condition of charging and discharging, the current in its battery cell branch is extremely low or there is no current, and the battery cell temperature does not rise significantly. The MCU determines that the system is in normal working condition based on the battery cell temperature and maintains the rated power output. However, the DC-DC power devices on the PCB are working continuously, and their temperature is constantly rising. This can easily cause the power devices to be in a state of operation above the rated temperature for a long time, which poses a risk of thermal failure and reduced reliability, and will also cause the surface temperature of the casing to exceed the national standard limit.

[0003] To avoid the above problems, the traditional solution is to set the cell temperature threshold to a small, conservative value, which prevents the cell from fully releasing its actual performance. When the cell temperature rises slightly due to environmental or operating conditions, the system triggers a power reduction, significantly shortening the continuous high-power output and input time and reducing product performance.

[0004] Therefore, designing a temperature control method and mobile power supply that can balance high power output and reliability is of great importance to those skilled in the art. Summary of the Invention

[0005] This invention provides a temperature control method and a power bank that can balance high power output and reliability, thereby solving the problem in the prior art that it is difficult to balance charging safety and high power output.

[0006] A temperature control method, applied to a power bank with a multi-channel DC-DC architecture, comprises the following steps:

[0007] Identify the current operating conditions and collect the cell temperature and PCB heat source temperature; When in charging / discharging mode, if the cell temperature is higher than the first preset threshold or the PCB heat source temperature is higher than the second preset threshold, the current power is reduced to a power value that matches the current temperature. When in a charging and discharging state, if the cell temperature is higher than the first preset threshold or the PCB heat source temperature is higher than the third preset threshold, the current power will be reduced to a power value that matches the current temperature. The second preset threshold is higher than the third preset threshold.

[0008] Optionally, the following steps are also included: Preset cell temperature-power conversion table; If the cell temperature is higher than the first preset threshold, the current power is reduced to the power corresponding to the current cell temperature in the cell temperature-power correspondence table.

[0009] Optionally, the following steps are also included: Preset table of temperature-power correspondence of the first PCB heat source under charging / discharging conditions; If the PCB heat source temperature is higher than the second preset threshold during charging / discharging, the current power is reduced to the power corresponding to the current PCB heat source temperature in the first PCB heat source temperature-power correspondence table.

[0010] Optionally, the following steps are also included: Preset table of temperature-power correspondence of the second PCB heat source under the condition of simultaneous charging and discharging; If the PCB heat source temperature is higher than the third preset threshold under the condition of charging and discharging simultaneously, the current power is reduced to the power corresponding to the current PCB heat source temperature in the second PCB heat source temperature-power correspondence table.

[0011] Optionally, the following steps are also included: If, during charging / discharging, the cell temperature is higher than the first preset threshold and the PCB heat source temperature is higher than the second preset threshold, the current power is reduced to the lowest power value between the current cell temperature in the cell temperature-power correspondence table and the current PCB heat source temperature in the first PCB heat source temperature-power correspondence table.

[0012] Optionally, the following steps are also included: If, during simultaneous charging and discharging, the cell temperature exceeds the first preset threshold and the PCB heat source temperature exceeds the third preset threshold, the current power is reduced to the lowest power value between the power corresponding to the current cell temperature in the cell temperature-power correspondence table and the power corresponding to the current PCB heat source temperature in the second PCB heat source temperature-power correspondence table.

[0013] Optionally, the following steps are also included: When in charging / discharging mode, if the cell temperature is within the first preset threshold and the PCB heat source temperature is within the second preset threshold, the current power is maintained. When in a charging and discharging state, if the cell temperature is within the first preset threshold and the PCB heat source temperature is within the third preset threshold, the current power will be maintained.

[0014] Optionally, the following steps are also included: If the cell temperature is higher than the first preset threshold, and the current power is less than or equal to the power value corresponding to the current cell temperature in the cell temperature-power correspondence table, then the current power will be maintained.

[0015] Optionally, the following steps are also included: If the PCB heat source temperature is higher than the second preset threshold during charging / discharging, and the current power is less than or equal to the power value corresponding to the current PCB heat source temperature in the first PCB heat source temperature-power correspondence table, then the current power is maintained. If the PCB heat source temperature is higher than the third preset threshold under the condition of simultaneous charging and discharging, and the current power is less than or equal to the power value corresponding to the current PCB heat source temperature in the second PCB heat source temperature-power correspondence table, then the current power is maintained.

[0016] To address the problems existing in the prior art, the present invention also provides a portable power bank, the solution of which is used to implement the above-mentioned temperature control method, comprising: Battery cell; The lithium protection module has its input terminal electrically connected to the battery cell. The first DC-DC module and the second DC-DC module are electrically connected to the output of the lithium battery module. A first interface module and a second interface module, wherein the input terminal of the first interface module is electrically connected to the output terminal of the first interface module, and the input terminal of the second interface module is electrically connected to the output terminal of the second DC-DC module; Multiple temperature sampling units are provided, and the main control module is respectively disposed on the battery cell, the first DC-DC module and the second DC-DC module; The main control module has its input terminal electrically connected to the output terminal of the lithium protection module, and its acquisition terminal is connected to multiple temperature sampling units.

[0017] The beneficial effects of the temperature control method provided in this invention are as follows: the first preset threshold is used for all operating conditions of the battery cell, which can stably ensure the safe operation of the battery cell; the PCB heat source is set with different second and third preset thresholds based on different operating conditions. When charging or discharging, a higher second preset threshold is used to avoid premature power reduction, effectively release the battery cell performance, and extend the high-power continuous working time. When charging and discharging simultaneously, a lower third preset threshold is selected, which can reduce the power in advance based on the temperature of the PCB heat source when the temperature rise of the battery cell is not obvious, suppress the overheating of the DC-DC power device, and avoid the risk of high-temperature failure of the device; by controlling the heat generation of the PCB heat source in advance, the heat conduction to the outer casing can be reduced, so that the surface temperature of the outer casing meets the national standard requirements, improving the product's compliance and user experience. Attached Figure Description

[0018] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. In the accompanying drawings: Figure 1 This is a flowchart of the temperature control method in an embodiment of the present invention. Figure 1 ; Figure 2 This is a flowchart of the temperature control method in an embodiment of the present invention. Figure 2 ; Figure 3 This is a flowchart of the temperature control method in an embodiment of the present invention. Figure 3 ; Figure 4 This is a flowchart of the temperature control method in an embodiment of the present invention. Figure 4 ; Figure 5 This is a module block diagram of the mobile power supply in an embodiment of the present invention; Figure 6 This is a circuit diagram of the main control module in an embodiment of the present invention; Figure 7 This is a circuit diagram of the temperature sampling unit in an embodiment of the present invention.

[0019] The labels for the attached figures are as follows: 1. Battery cell; 2. Lithium protection module; 3. First DC-DC module; 4. Second DC-DC module; 5. First interface module; 6. Second interface module; 7. Main control module; 8. Temperature sampling unit. Detailed Implementation

[0020] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0021] like Figures 1 to 4 As shown, the present invention provides a specific embodiment of a temperature control method.

[0022] A temperature control method is applied to a power bank with a multi-channel DC-DC architecture, referenced. Figure 1 This includes the following steps: S1. Identify the current operating conditions and collect the cell temperature and PCB heat source temperature; S2. When in charging / discharging mode, if the cell temperature is higher than the first preset threshold or the PCB heat source temperature is higher than the second preset threshold, the current power is reduced to a power value that matches the current temperature. S3. When in the charging and discharging mode, if the cell temperature is higher than the first preset threshold or the PCB heat source temperature is higher than the third preset threshold, the current power is reduced to a power value that matches the current temperature. The second preset threshold is higher than the third preset threshold.

[0023] Step 1: After the power bank completes hardware initialization upon power-on, the main control MCU monitors the connection status of the power input and output interfaces in real time. Based on whether a power adapter is connected to the input and whether an external electrical load is connected to the output, it logically distinguishes three operating modes: stand-alone charging, stand-alone discharging, and simultaneous charging and discharging. Simultaneously, NTC thermistors located at the lithium battery cells and those mounted on the multi-channel DC-DC power devices collect resistance signals in real time and transmit them to the MCU's built-in ADC sampling pin. The MCU then converts the resistance signals using an internal preset conversion formula. The data is converted into corresponding actual temperature values. Temperature data of the battery cell area and the power devices (heat sources) on the PCB board are collected synchronously and continuously. The real-time temperature parameters are stored in a register, providing reliable data support for subsequent threshold comparison under different operating conditions and power adjustment. This breaks away from the traditional temperature measurement mode that only collects the temperature of a single point of the battery cell. This step realizes synchronous temperature measurement of multiple heat source points of the whole machine and accurate identification of operating conditions. It can keep track of the temperature rise changes of the core heat sources of the battery cell and PCB power devices in real time, solve the shortcomings of traditional solutions that lack PCB heat source temperature monitoring and one-sided heat source data collection, and provide a data foundation for differentiated threshold control.

[0024] Step 2: When the device determines that it is operating in a standalone charging or discharging mode, a large current flows through both the battery cell circuit and the PCB-side DC-DC circuit. The battery cell and PCB power devices heat up simultaneously. Under normal operating conditions, the temperature rise rate of the battery cell is higher than that of the PCB power devices. Therefore, the configuration value of the PCB heat source adopts a higher second preset threshold. The MCU cyclically retrieves the real-time temperature data in the register, compares the battery cell temperature with the first preset threshold, and compares the PCB heat source temperature with the second preset threshold. As long as the measured temperature of the battery cell exceeds the first preset threshold and the measured temperature of the PCB heat source exceeds the second preset threshold, the device will be charged. If either of the two conditions of the second preset threshold is met, the MCU immediately sends a control command to the back-end power management chip to reduce the input or output power of the whole device to a preset safe power value that matches the current temperature. By adopting a higher PCB heat source threshold design under charging and discharging conditions, the power reduction is avoided when the PCB temperature rises slightly. This abandons the traditional conservative design of blindly reducing power for temperature control. When the cell temperature does not exceed the standard, the output capacity of the whole device can be preserved to the maximum extent, fully releasing the rated performance of the cell itself, effectively extending the working time of the power bank for continuous high-power charging and discharging, and improving the fast charging experience.

[0025] Step 3: After the device enters the charging and discharging mode, one end of the power supply is connected to the adapter for charging, and the other end is discharging externally. Due to the influence of the internal circuit topology of the power supply, the current flowing through the cell branch is very small, the cell generates little heat, and the temperature rises slowly, making it difficult to reach the first preset threshold. Most of the heat of the entire device is generated by the operation of multiple independent DC-DC power devices, and the PCB board becomes the main heat source of the entire device. Based on the heat generation characteristics of this operating condition, the PCB heat source adopts a lower third preset threshold. The MCU continuously compares the real-time temperature. If the cell temperature exceeds the first preset threshold or the PCB heat source temperature exceeds the third preset threshold, the device will be charged. If any condition is met, a power reduction operation is immediately executed, lowering the overall power to a pre-set safe power value that matches the current temperature. Simultaneous charging and discharging relies on a lower third preset threshold to achieve early temperature control. If the PCB temperature exceeds the limit before the cell temperature rise exceeds the limit, the overall power can be limited in advance, reducing the heat generation of DC-DC power devices from the source and avoiding problems such as excessive junction temperature and component aging failure due to long-term high-temperature operation of power devices. At the same time, it reduces the heat conduction from the PCB to the power supply casing, effectively controlling the surface temperature of the casing to meet national standards and avoiding product compliance risks.

[0026] Specifically, when in charging / discharging mode, if the cell temperature is within the first preset threshold and the PCB heat source temperature is within the second preset threshold, the current power is maintained; when in simultaneous charging and discharging mode, if the cell temperature is within the first preset threshold and the PCB heat source temperature is within the third preset threshold, the current power is maintained.

[0027] In this embodiment, the first preset threshold is used across all operating conditions of the battery cell, which can stably ensure the safe operation of the battery cell. The PCB heat source is set with different second and third preset thresholds based on different operating conditions. When charging or discharging, the higher second preset threshold is used to avoid premature power reduction, effectively release the battery cell performance, and extend the high-power continuous working time. When charging and discharging simultaneously, the lower third preset threshold is selected, which can reduce the power in advance based on the temperature of the PCB heat source when the temperature rise of the battery cell is not obvious, suppress the overheating of the DC-DC power device, and avoid the risk of device failure due to high temperature. By controlling the heat generation of the PCB heat source in advance, the heat conduction to the outer casing can be reduced, so that the surface temperature of the outer casing meets the national standard requirements, improving the product's compliance and user experience.

[0028] In one embodiment, reference Figure 2 The temperature control method also includes the following steps: S21. Preset cell temperature-power correspondence table; S22. If the cell temperature is higher than the first preset threshold, reduce the current power to the power corresponding to the current cell temperature in the cell temperature-power correspondence table.

[0029] Step 21: During the MCU programming stage of the power bank, multiple segmented cell temperature nodes are pre-calibrated based on cell specifications, cell heat resistance characteristics, and cell discharge decay curves under different ambient temperatures. Following the rule that higher temperatures result in lower maximum allowable output power, a one-to-one cell temperature-power matching data table is established and stored in the MCU's internal storage. This data table divides multiple temperature ranges, each with its own matched rated operating power, rather than a single temperature corresponding to a uniform power. Furthermore, this data table is universally applicable across all operating conditions, using the same cell power matching standard for charging, discharging, and simultaneous charging and discharging modes. This step standardizes temperature control data through pre-establishing tables, moving away from the traditional fixed-level, one-off power reduction control method. This provides data support for subsequent refined, stepped power adjustment, allowing the power reduction to smoothly transition with temperature changes.

[0030] Step 22: During normal operation of the device, the MCU of the power bank collects the real-time temperature value of the battery cell through NTC sampling and continuously compares the collected temperature with the first preset threshold. When the measured temperature of the battery cell exceeds the first preset threshold, the MCU immediately retrieves the pre-stored battery cell temperature-power correspondence table, searches for the rated power limit corresponding to the current battery cell temperature range, and then sends a control command to the power management chip to control the input or output power of the whole device to be accurately reduced to the target power obtained by looking up the table. This step relies on the table lookup method to realize the graded power reduction of the battery cell. If the battery cell temperature is slightly overheated, the power is reduced slightly. If the battery cell temperature rises severely, the power reduction is increased. Under the premise of reliably protecting the battery cell from damage due to high temperature, the output power of the device is preserved as much as possible, avoiding abnormal problems such as sudden interruption of charging of external devices and disconnection of fast charging protocol caused by a cliff drop in power, thus improving the continuity of power supply.

[0031] If the cell temperature is higher than the first preset threshold and the current power is less than or equal to the power value corresponding to the current cell temperature in the cell temperature-power correspondence table, then the current power is maintained.

[0032] In this embodiment, compared to the conventional fixed threshold direct power reduction control scheme, this embodiment relies on a pre-stored cell temperature and power table to achieve a stepped and smooth power reduction. The power change is gradual, and the power supply is stable when connected to external loads such as mobile phones and laptops, effectively improving the user experience. Combined with the original PCB dual-threshold temperature control logic for different working conditions, the cell adopts a lookup table for fine-grained temperature control, which can not only ensure the safety of the cell under all working conditions, but also avoid excessive power restriction due to slight temperature rise of the cell. This is conducive to fully utilizing the cell's discharge performance and extending the continuous high-power output time of the power bank. The cell-level temperature control and PCB dual-threshold control work together to manage two heat sources in layers, optimize the overall thermal balance, reduce abnormal heat generation at the cell level, and help the overall temperature control system achieve a balance between safety and performance, improving the reliability of the power bank in all scenarios.

[0033] In one embodiment, reference Figure 3 The temperature control method also includes the following steps: S23. Preset the first PCB heat source temperature-power correspondence table under charging / discharging conditions; S24. If the PCB heat source temperature is higher than the second preset threshold under charging / discharging conditions, reduce the current power to the power corresponding to the current PCB heat source temperature in the first PCB heat source temperature-power correspondence table. S25. If the cell temperature is higher than the first preset threshold and the PCB heat source temperature is higher than the second preset threshold during charging / discharging, then reduce the current power to the lowest power value between the power corresponding to the current cell temperature in the cell temperature-power correspondence table and the power corresponding to the current PCB heat source temperature in the first PCB heat source temperature-power correspondence table.

[0034] Step 23: During the power bank firmware development phase, based on the heat resistance parameters of multiple DC-DC power devices, actual PCB heating data under charging and discharging conditions, multiple continuous PCB temperature ranges are defined. Following the rule that higher PCB temperatures correspond to lower maximum allowable power, the safety limit power for each temperature is calibrated, generating a corresponding first PCB heat source temperature-power correspondence table, which is then stored in the MCU storage area. This table is only accessed during standalone charging and discharging conditions and is not used in simultaneous charging and discharging scenarios. By completing the power data calibration in advance, a graded power reduction data benchmark can be provided for PCB overheating under charging and discharging conditions, eliminating the crude control method of directly and drastically limiting power upon overheating and achieving refined power regulation at the PCB end.

[0035] Step 24: During the charging or discharging process, the MCU collects the PCB heat source temperature in real time and continuously compares the measured temperature with the second preset threshold. Once the PCB heat source exceeds the second preset threshold, the MCU retrieves the first PCB heat source temperature-power correspondence table, matches the current PCB heat source with the corresponding power limit, and issues a control command to reduce the overall power to the power value obtained from the table. The power is smoothly reduced according to the PCB heat source temperature gradient. The lower the temperature rise, the smaller the power reduction. While constraining the temperature rise of PCB components, the output capacity is preserved to the maximum extent, avoiding unnecessary power loss.

[0036] Step 25: During charging or discharging, when the cell temperature and the PCB heat source temperature both exceed their respective preset thresholds, the MCU queries the power matched to the current cell temperature and the power matched to the current PCB heat source temperature, compares the two power values, selects the smaller value as the final operating power, and controls the power management chip to complete the power reduction. When both heat sources exceed the temperature simultaneously, the lower limit power is selected to prioritize meeting the temperature control requirements of the side with more stringent temperature rise, and simultaneously achieves dual safety protection for the cell and power devices.

[0037] If the PCB heat source temperature is higher than the second preset threshold during charging / discharging, and the current power is less than or equal to the power value corresponding to the current PCB heat source temperature in the first PCB heat source temperature-power correspondence table, then the current power is maintained.

[0038] In this embodiment, a PCB lookup table temperature control is added for charging and discharging conditions. Combined with the original second high threshold setting, unnecessary power compression is further reduced, effectively extending the continuous high-power output time and fully releasing the rated performance of the battery cell. Furthermore, the power reduction is implemented by looking up the table separately when a single heat source overheats, and the minimum power limit is applied when two heat sources overheat simultaneously. This hierarchical and graded management, along with rigorous temperature control logic, avoids the risk of battery cell overheating and prevents DC-DC power devices from operating at high temperatures for extended periods. The stepped lookup table power reduction ensures smooth power changes, preventing sudden power drops that could cause disconnections during fast charging of external devices, thus improving the stability of the load power supply and the user experience.

[0039] In one embodiment, reference Figure 4 The temperature control method also includes the following steps: S31. Preset the temperature-power correspondence table of the second PCB heat source under the condition of simultaneous charging and discharging; S32. If the PCB heat source temperature is higher than the third preset threshold under the condition of charging and discharging simultaneously, the current power is reduced to the power corresponding to the current PCB heat source temperature in the second PCB heat source temperature-power correspondence table.

[0040] S33. If, during simultaneous charging and discharging, the cell temperature is higher than the first preset threshold and the PCB heat source temperature is higher than the third preset threshold, then the current power is reduced to the lowest power value between the power corresponding to the current cell temperature in the cell temperature-power correspondence table and the power corresponding to the current PCB heat source temperature in the second PCB heat source temperature-power correspondence table.

[0041] Step 31: During the power bank firmware development phase, based on the heat resistance parameters of multiple DC-DC power devices and the measured heat generation data of the PCB heat source under simultaneous charging and discharging conditions, multiple continuous PCB temperature ranges are defined. According to the rule that the higher the PCB temperature, the lower the maximum allowable operating power, the safety limit power corresponding to each temperature is calibrated, and a corresponding second PCB heat source temperature-power correspondence table is generated and stored in the MCU storage area. This table is only called during simultaneous charging and discharging conditions. By completing the power data calibration in advance, a data benchmark for graded power reduction is provided for PCB heat source overheating under simultaneous charging and discharging conditions, thus getting rid of the coarse control method of directly and drastically limiting power at the moment of overheating and realizing fine power adjustment at the PCB end.

[0042] Step 32: During the charging and discharging process, the MCU collects the PCB heat source temperature in real time and continuously compares the measured temperature with the third preset threshold. Once the PCB heat source exceeds the third preset threshold, the MCU retrieves the second PCB heat source temperature-power correspondence table, matches the current PCB heat source with the corresponding power limit, and issues a control command to reduce the overall power to the power value obtained from the table. The power is smoothly reduced according to the PCB heat source temperature gradient. The lower the temperature rise, the smaller the power reduction. While constraining the temperature rise of PCB components, the output capacity is preserved to the maximum extent, avoiding unnecessary power loss.

[0043] Step 33: During simultaneous charging and discharging, when the cell temperature and the PCB heat source temperature both exceed their respective preset thresholds, the MCU queries the power matched to the current cell temperature and the power matched to the current PCB heat source temperature, compares the two power values, selects the smaller value as the final operating power, and controls the power management chip to complete the power reduction. When both heat sources exceed the temperature simultaneously, the lower limit power is selected to prioritize meeting the temperature control requirements of the side with more stringent temperature rise, and simultaneously achieves dual safety protection for the cell and power devices.

[0044] If the PCB heat source temperature is higher than the third preset threshold under the condition of simultaneous charging and discharging, and the current power is less than or equal to the power value corresponding to the current PCB heat source temperature in the second PCB heat source temperature-power correspondence table, then the current power is maintained.

[0045] In this embodiment, a separate second PCB power reference table is configured for charging and discharging, along with a third low-temperature threshold. This allows for precise and gradual power limiting under conditions where the cell temperature rise is low and the PCB heats up first, effectively controlling the junction temperature of the device and the surface temperature of the casing to meet national standard temperature rise requirements. Two independent PCB temperature and power tables are distinguished for charging / discharging and charging / discharging, and combined with different operating condition thresholds, to achieve differentiated and refined temperature control for the two scenarios. The power limit is relaxed for charging / discharging to improve battery life and full-load duration, while temperature control is tightened for charging / discharging to ensure heat dissipation compliance. Power is reduced by referring to a separate table when a single heat source exceeds the limit, and the minimum power limit is applied when two heat sources exceed the limit. Power adjustment is smooth and continuous, preventing sudden and significant power drops that could cause external devices to stop charging or fast charging to disconnect, thus improving product stability.

[0046] like Figures 5 to 7 As shown, the present invention also provides a specific embodiment of a portable power bank.

[0047] A portable power bank, reference Figures 5 to 7 The power bank includes a battery cell 1, a lithium protection module 2, a first DC-DC module 3, a second DC-DC module 4, a first interface module 5, a second interface module 6, a main control module 7, and multiple temperature sampling units 8. The input terminal of the lithium protection module 2 is electrically connected to the battery cell 1, and the output terminal of the lithium protection module 2 is electrically connected to the input terminals of the main control module 7, the first DC-DC module 3, and the second DC-DC module 4, respectively. The output terminal of the first DC-DC module 3 is electrically connected to the first interface module 5, and the output terminal of the second interface module 6 is electrically connected to the second interface module 6. Multiple temperature sampling units 8 are respectively disposed on the battery cell 1, the first DC-DC module 3, and the second DC-DC module 4, and are all connected to the main control module 7.

[0048] Specifically, the battery cell 1 serves as the energy storage carrier of the mobile power supply, responsible for storing electrical energy. When charging, it receives electrical energy input from the external adapter, and when discharging, it provides basic power to the lithium protection module 2, the first DC-DC module 3, the second DC-DC module 4, and the main control module 7. The battery cell 1 is equipped with a temperature sampling unit 8 to collect its own temperature in real time and transmit it to the main control module 7.

[0049] The lithium protection module 2 is connected between the battery cell 1 and the back-end circuit. On the one hand, it monitors the voltage and circuit current of the battery cell 1 in real time and uses hardware circuits to realize overcharge, over-discharge, overcurrent and short circuit protection of the battery cell 1. When the battery cell 1 has an electrical fault, it quickly cuts off the circuit. On the other hand, it performs voltage regulation on the output voltage of the battery cell 1 and stably supplies power to the downstream main controller, the first DC-DC module 3 and the second DC-DC module 4.

[0050] The first DC-DC module 3 and the second DC-DC module 4 are independent of each other. They receive the electrical energy output from the lithium battery module 2, convert the voltage of the battery cell 1 into a working voltage that is compatible with the fast charging protocol through buck-boost conversion, and drive the first interface module 5 and the second interface module 6 respectively to realize power input and output. Temperature sampling units 8 are evenly distributed on the surface of the DC-DC power devices of the first DC-DC module 3 and the second DC-DC module 4 to collect the PCB heat source temperature in real time, and at the same time receive the control commands issued by the main controller to complete the power increase or decrease adjustment.

[0051] The main control module 7 is the control center of the whole machine. It receives the temperature data transmitted back by each temperature sampling unit 8 and the access status signal of the interface module. It internally stores the first temperature threshold, the second temperature threshold and the third temperature threshold. It performs data comparison and calculation according to the temperature control logic of different working conditions, and sends power adjustment command to the DCDC module according to the temperature judgment result. Multiple sets of temperature sampling units 8 are fixed at the key heat-generating positions of the battery cell 1, the first DCDC module 3 and the second DCDC module 4 respectively. Utilizing the physical characteristics of the thermistor's resistance changing with temperature, the temperature change is converted into an electrical signal and sent to the ADC pin of the main control module to complete the temperature acquisition of the battery cell 1 and the PCB heat source, and provide raw temperature data for the temperature control logic calculation.

[0052] When the device is powered on, the main control module 7 identifies three operating conditions—charging, discharging, and simultaneous charging and discharging—through the access status of the two interface modules. The temperature sampling unit 8 continuously collects the temperature of the battery cell 1, the PCB heat source temperature of the first DC-DC module 3, and the PCB heat source temperature of the second DC-DC module 4, and uploads them to the main control module 7. In the charging and discharging condition, the PCB heat source uses a second preset threshold with a higher value. In the simultaneous charging and discharging condition, the PCB heat source uses a third preset threshold with a lower value. The battery cell 1 uses the first preset threshold uniformly in all operating conditions. When the temperature of the battery cell 1 exceeds the first threshold or the temperature of the PCB heat source exceeds the limit in the corresponding operating condition, the main control module 7 immediately controls the corresponding first DC-DC module 3 or second DC-DC module 4 to reduce the operating power. The lithium protection module 2 protects the electrical safety of the battery cell 1 from the hardware level throughout the process, thereby completing the entire set of dual-threshold temperature control for different operating conditions.

[0053] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Those skilled in the art can modify the technical solutions described in the above embodiments, or make equivalent substitutions for some of the technical features; and all such modifications and substitutions should fall within the protection scope of the appended claims of the present invention.

Claims

1. A temperature control method applied to a mobile power bank with a multi-channel DC-DC architecture, characterized in that, Includes the following steps: Identify the current operating conditions and collect the cell temperature and PCB heat source temperature; When in charging / discharging mode, if the cell temperature is higher than the first preset threshold or the PCB heat source temperature is higher than the second preset threshold, the current power is reduced to a power value that matches the current temperature. When in a charging and discharging state, if the cell temperature is higher than the first preset threshold or the PCB heat source temperature is higher than the third preset threshold, the current power will be reduced to a power value that matches the current temperature. The second preset threshold is higher than the third preset threshold.

2. The temperature control method according to claim 1, characterized in that, It also includes the following steps: Preset cell temperature-power conversion table; If the cell temperature is higher than the first preset threshold, the current power is reduced to the power corresponding to the current cell temperature in the cell temperature-power correspondence table.

3. The temperature control method according to claim 2, characterized in that, It also includes the following steps: Preset table of temperature-power correspondence of the first PCB heat source under charging / discharging conditions; If the PCB heat source temperature is higher than the second preset threshold during charging / discharging, the current power is reduced to the power corresponding to the current PCB heat source temperature in the first PCB heat source temperature-power correspondence table.

4. The temperature control method according to claim 3, characterized in that, It also includes the following steps: Preset table of temperature-power correspondence of the second PCB heat source under the condition of simultaneous charging and discharging; If the PCB heat source temperature is higher than the third preset threshold under the condition of charging and discharging simultaneously, the current power is reduced to the power corresponding to the current PCB heat source temperature in the second PCB heat source temperature-power correspondence table.

5. The temperature control method according to claim 4, characterized in that, It also includes the following steps: If, during charging / discharging, the cell temperature is higher than the first preset threshold and the PCB heat source temperature is higher than the second preset threshold, the current power is reduced to the lowest power value between the current cell temperature in the cell temperature-power correspondence table and the current PCB heat source temperature in the first PCB heat source temperature-power correspondence table.

6. The temperature control method according to claim 4, characterized in that, It also includes the following steps: If, during simultaneous charging and discharging, the cell temperature exceeds the first preset threshold and the PCB heat source temperature exceeds the third preset threshold, the current power is reduced to the lowest power value between the power corresponding to the current cell temperature in the cell temperature-power correspondence table and the power corresponding to the current PCB heat source temperature in the second PCB heat source temperature-power correspondence table.

7. The temperature control method according to claim 1, characterized in that, It also includes the following steps: When in charging / discharging mode, if the cell temperature is within the first preset threshold and the PCB heat source temperature is within the second preset threshold, the current power is maintained. When in a charging and discharging state, if the cell temperature is within the first preset threshold and the PCB heat source temperature is within the third preset threshold, the current power will be maintained.

8. The temperature control method according to claim 2, characterized in that, It also includes the following steps: If the cell temperature is higher than the first preset threshold, and the current power is less than or equal to the power value corresponding to the current cell temperature in the cell temperature-power correspondence table, then the current power will be maintained.

9. The temperature control method according to claim 4, characterized in that, It also includes the following steps: If the PCB heat source temperature is higher than the second preset threshold during charging / discharging, and the current power is less than or equal to the power value corresponding to the current PCB heat source temperature in the first PCB heat source temperature-power correspondence table, then the current power is maintained. If the PCB heat source temperature is higher than the third preset threshold under the condition of simultaneous charging and discharging, and the current power is less than or equal to the power value corresponding to the current PCB heat source temperature in the second PCB heat source temperature-power correspondence table, then the current power is maintained.

10. A portable power bank, characterized in that, To implement the temperature control method as described in any one of claims 1-7, comprising: Battery cell; The lithium protection module has its input terminal electrically connected to the battery cell. The first DC-DC module and the second DC-DC module are electrically connected to the output of the lithium battery module. A first interface module and a second interface module, wherein the input terminal of the first interface module is electrically connected to the output terminal of the first interface module, and the input terminal of the second interface module is electrically connected to the output terminal of the second DC-DC module; Multiple temperature sampling units are provided, and the main control module is respectively disposed on the battery cell, the first DC-DC module and the second DC-DC module; The main control module has its input terminal electrically connected to the output terminal of the lithium protection module, and its acquisition terminal is connected to multiple temperature sampling units.

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