Functional heterogeneous hot redundant high-reliability spacecraft lithium ion battery charging control method

Abstract

The invention provides a functional isomerism hot redundancy high-reliability spacecraft lithium ion battery charging control method, a lithium ion battery is formed by connecting a plurality of battery monomers or battery parallel blocks in series, and the lithium ion battery receives current from a solar battery array for charging and is used for supplying power to a spacecraft load. Comprising a main charging control circuit and a backup charging control circuit which are functional isomerism hot redundancy charging control circuits, and automatic circulation charging is achieved through a charging starting circuit which is also functional isomerism hot redundancy charging control circuits. The control method does not depend on software, so that the chip is prevented from being influenced by outer space irradiation and single event effect; common cause failure faults of main and backup measures can be avoided; the fault handling process does not depend on software judgment or manual decision intervention capacity, and the fault real-time autonomous handling capacity is achieved, and the reliability design requirement of a general spacecraft power supply system is completely met.

Description

A High-Reliability Spacecraft Lithium-ion Battery Charging Control Method with Functional Heterogeneous Thermal Redundancy Technical Field

[0001] This invention relates to spacecraft power system charging control technology, and more particularly to a highly reliable spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy. Background Technology

[0002] Lithium-ion batteries, as increasingly mature chemical batteries, have been widely used in the aerospace field over the past decade, serving as the preferred energy storage battery type for power systems in various spacecraft such as satellites, spacecraft, and space stations. Compared to other types of batteries, lithium-ion batteries have excellent characteristics such as high energy density and high charge retention, but they also have disadvantages such as being susceptible to overcharging and thermal failure. Therefore, in the aerospace field, lithium-ion battery charging control technology must not only ensure that the battery is fully charged during periods of sunlight, but also guarantee the reliability and safety of the charging process.

[0003] The charging control of lithium-ion batteries generally consists of two functions: charging control and charging protection. The charging control function enables automatic cyclic charging of the battery. Specifically, charging begins when the spacecraft enters a sunlit area, typically powered by solar cells. Charging is terminated automatically by reducing the charging current when the battery voltage reaches a set charging value. The charging protection function ensures safety during the charging process, generally by forcibly terminating charging when the battery voltage or temperature reaches a safety set value. Because the charging control and protection functions of lithium-ion batteries are complex, they are generally implemented through software algorithms or a control scheme that primarily uses software algorithms with hardware circuitry as a backup.

[0004] In terms of existing technologies for implementing charging control functions, patent document CN107785969 proposes a software-based segmented voltage limiting and current shunt charging control method, but the main charging function lacks redundancy measures; patent document CN1075428742 proposes a constant current voltage limiting and current shunt charging control method, although a three-out-of-two redundancy design is used in some circuits, the main charging function still lacks redundancy measures; patent document CN106602666 proposes a segmented voltage limiting and current shunt charging control method, but the main charging function still lacks redundancy measures; patent document CN104426140 proposes a software-based method... The hardware-based charging control and protection method, which switches between the main charging control circuit and the backup charging control circuit after determining a battery voltage fault through software, employs two circuit redundancies, but these are all of the same type and lack heterogeneity and thermal redundancy backup measures. Regarding the implementation of charging protection, patent document CN110994713 proposes a microcontroller-based charging protection method that forcibly terminates charging after determining whether the battery voltage or temperature exceeds a safety setting. While this method also employs two circuit redundancies, these are all of the same type and lack heterogeneity.

[0005] Current aerospace charging control technology has a certain degree of control function redundancy. More complex designs generally adopt primary and backup measures in the main function circuit design. The primary and backup circuits can switch between working circuits by issuing instructions through software under certain judgment logic. However, since the primary and backup circuits use the same type of circuit design, there is a common cause failure mode (failure due to the same reason). Moreover, the primary and backup circuits cannot be on duty at the same time, and only one of them can be selected as the working circuit (i.e., cold redundancy / cold backup). There is a risk of delayed manual intervention and software misjudgment in the handling of emergency failures. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a highly reliable spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy. The lithium-ion battery is composed of several individual battery cells or parallel blocks connected in series. The lithium-ion battery receives current from a solar array for charging and is used to power the spacecraft load. The method is characterized by comprising: a charging control system composed of two functionally heterogeneous thermal redundancy charging control circuits—a primary charging control circuit and a backup charging control circuit—and an automatic cyclic charging system achieved through a charging start-up circuit also composed of two functionally heterogeneous thermal redundancy circuits.

[0007] Furthermore, the functional heterogeneity of the charging control circuit refers to the combination of two completely different charging control methods used in the primary and backup charging control circuits. Specifically, the primary charging control circuit adopts a full current shunting control method, while the backup charging control circuit adopts an open-circuit control method.

[0008] Furthermore, the thermal redundancy of the charging control circuit means that both the primary and backup charging control circuits are effective on duty. As the battery voltage gradually increases during the charging process, the primary function takes priority to achieve full charge control. When the primary function fails partially or completely due to a fault, the backup function automatically takes over to achieve full charge control. The fault handling process does not rely on software judgment or manual decision-making intervention.

[0009] Furthermore, the functional heterogeneity of the charging start-up circuit refers to the use of two start-up signals with different physical sources and opposite control logic, namely, the output voltage source charging start-up signal and the input current source charging start-up signal.

[0010] Furthermore, the thermal redundancy of the charging start circuit means that charging can be automatically started as long as any charging start signal is valid.

[0011] Furthermore, the primary charging control circuit is prioritized for effectiveness, while the backup charging control circuit serves as a hot redundancy backup. The primary full-charge shunt control reference is preset and selects multiple levels through a hardware comparison circuit, with a certain dead interval set between each reference level. The backup full-charge open-circuit control reference is also preset and selects multiple levels through a hardware comparison circuit, with a certain dead interval set between each reference level. Each level of the full-charge open-circuit control reference is higher than each level of the corresponding full-charge shunt control reference, with a certain voltage interval set.

[0012] Furthermore, the gear position for the full shunt control reference is selected via a hardware selection circuit based on the energy balance requirements of the spacecraft's on-orbit flight mission.

[0013] Furthermore, the maximum setting of the open-circuit control reference does not exceed the upper limit of the safe charging voltage of a single lithium-ion battery cell.

[0014] Furthermore, for the shading charging start signal, the shading charging start circuit collects the voltage signal of a certain solar cell subarray. This signal is a voltage quantity. When the rising edge of the solar cell subarray voltage signal exceeds a set value after the spacecraft enters the sunlit area, it serves as a sign of shading. For the shading charging start signal, the shading charging start circuit collects the current signal of a certain solar cell string. This signal is a current quantity. When the spacecraft enters the shadow area, when the falling edge of the solar cell subarray current signal is less than a set value, it serves as a sign of shading.

[0015] Furthermore, as the battery voltage gradually rises during the charging process, it first reaches the full charge shunt control reference value, and then prioritizes the main charging shunt control, while the backup charging control provides thermal redundancy. If the main charging control fails partially or completely due to a fault and cannot perform full charging shunt, and there is still residual charging current causing the battery voltage to continue to rise, the backup charging control automatically takes over and achieves full charge control.

[0016] Compared with the prior art, the present invention has the following advantages: the present invention is based on a fully hardware circuit design, does not rely on software, and avoids the chip being affected by outer space irradiation and single-event effects.

[0017] This invention, by adopting a heterogeneous combination of primary and backup measures, can avoid failures caused by common factors in the primary and backup measures. By adopting primary and backup measures to be on duty simultaneously (i.e., hot redundancy / hot backup), it has the ability to handle faults autonomously in real time, without relying on software judgment or manual decision-making, thus reducing the risk of lag and software misjudgment in handling emergency faults.

[0018] The all-hardware circuit of this invention adopts a multi-redundancy design, eliminating single-point failure modes that may cause charging function failure, and achieving the design goal of "working after two failures and being safe after three failures" for the power system (meaning that it can still work after a second failure and does not affect battery safety after a third failure), fully meeting the usual reliability design requirement of "working after one failure and being safe after two failures" (meaning that it can still work after a first failure and does not affect battery safety after a second failure).

[0019] 1) The primary charging control circuit adopts an independent three-way redundancy design. A two-out-of-three voting circuit can eliminate a single fault in the primary charging control circuit. The backup charging control circuit, as a hot redundancy / hot backup of the primary charging control circuit, has the ability to automatically take over and continue normal operation even after the primary charging control circuit experiences one or even multiple faults. 2) Furthermore, the backup charging control circuit also adopts an independent three-way redundancy design. A two-out-of-three voting circuit can eliminate a single fault in the backup charging control circuit. It has the ability to continue normal operation even after the backup charging control circuit experiences another fault, even after the primary charging control circuit experiences one or even multiple faults. 3) Primary charging power... The circuit includes multiple solar cell subarrays isolated by series isolation diodes and their charging shunt circuits, allowing any solar cell subarray and its charging shunt circuit components to fail with open or short circuits; the backup charging control switch group and the charging protection switch group are combined in parallel and then in series, allowing any one of the charging control switches to fail to connect or disconnect; 4) In the event of multiple or more faults, as a safety measure, the charging control switch group or the charging protection switch group can be disconnected by remote control command signal to ensure the charging safety of the lithium-ion battery; the charging control switch group or the charging protection switch group can be re-closed by remote control command signal to restore the charging of the lithium-ion battery. Attached Figure Description

[0020] Figure 1 is a topology diagram of the high-reliability spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy according to the present invention. Detailed Implementation

[0021] The specific embodiments of the present invention will now be described in further detail with reference to the accompanying drawings.

[0022] This invention provides a highly reliable spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy, which is a fully hardware-controlled high-reliability charging control method for lithium-ion batteries. The lithium-ion battery is composed of several individual battery cells or parallel blocks connected in series. The lithium-ion battery receives current from a solar array for charging and is used to power the spacecraft load.

[0023] The high-reliability charging control method for lithium-ion batteries based on functional heterogeneous thermal redundancy using all-hardware circuitry of this invention does not rely on software, thus avoiding the impact of outer space irradiation and single-event effects on the chip. By adopting a functional heterogeneous combination of primary and backup measures in charging control, it can avoid common-cause failures of the primary and backup measures. By adopting primary and backup measures on duty simultaneously (i.e., thermal redundancy / hot backup), it has the ability to handle faults without relying on software judgment or manual decision-making intervention, and the ability to handle faults autonomously in real time. It can achieve the design goal of "operating under secondary faults and safe under tertiary faults" for the power system, fully meeting the reliability design requirements of "operating under primary faults and safe under secondary faults" for typical spacecraft power systems.

[0024] This invention comprises a charging control system consisting of two functionally heterogeneous and thermally redundant charging control circuits: a primary charging control circuit and a backup charging control circuit. Automatic cyclic charging is achieved through a charging start-up circuit.

[0025] The charging start-up circuit also consists of two functionally heterogeneous and thermally redundant circuits: an output charging start-up circuit and an input charging start-up circuit. The functional heterogeneity of the charging start-up circuit refers to the use of two start-up signals with different physical sources and opposite control logic: an output voltage source charging start-up signal and an input current source charging start-up signal. By adopting a functionally heterogeneous combination in the charging start-up, common-cause failures in the charging start-up circuit are avoided. The thermal redundancy of the charging start-up circuit means that automatic charging can be started as long as either charging start-up signal is valid.

[0026] The heterogeneous function of the charging control circuit refers to the combination of two completely different charging control methods used in the primary and backup circuits. Specifically, the primary charging control circuit employs a full-current shunting control method, where the charging current in the charging circuit is diverted to ground to achieve full battery charging once the individual battery cell voltage reaches the set charging voltage value. The backup charging control circuit employs an open-circuit control method, where the charging current in the charging circuit is opened to achieve full battery charging once the battery pack voltage reaches the set charging voltage value. This heterogeneous combination of primary and backup charging control measures avoids common-cause failures in both systems.

[0027] The thermal redundancy of the charging control circuit means that both the primary and backup circuits are effective on duty. As the battery voltage gradually rises during the charging process, the primary function takes priority to achieve full charge control. When the primary circuit fails partially or completely due to a fault, the backup function automatically takes over to achieve full charge control. The fault handling process does not rely on software judgment or manual decision-making intervention.

[0028] The main charging control circuit uses three independent lithium-ion battery cell voltage acquisition circuits 1 (a total of n cell voltages are sampled from a battery pack consisting of n cells or parallel blocks connected in series), three independent n-to-large hardware comparison circuits 2 (selecting the largest cell voltage from the n cell voltages), and three independent full-charge shunt control signal circuits 3 (setting the required full-charge shunt control reference value and performing comparison calculations). After passing through a three-out-of-two voting circuit 4, the final full-charge shunt control signal is sent to the drive circuit 5 (the number of charging shunt paths is designed according to the scale of the solar cell subarray, totaling m paths). When the lithium-ion battery cell voltage reaches the set full-charge shunt control reference value, the solar cell shunt circuit 6 is driven to shunt the current to complete the full-charge control.

[0029] Optionally, the full shunt control reference value can be preset via a hardware comparator circuit and can be set to V. d1 V d2 V d3 For each gear, a certain dead zone interval D is set between the reference values ​​of each gear. d The maximum charging setting should generally not exceed the upper limit of the safe charging voltage of a single lithium-ion battery cell; optionally, the full charge shunt control reference value V d1 V d2 V d3 The charging speed can be selected via a hardware selection circuit according to the energy balance requirements of the spacecraft's on-orbit flight mission. Optionally, the solar cell shunt circuit 6 can adopt segmented flexible shunt, which is beneficial for fully charging the lithium-ion battery under the same conditions. That is, when the voltage of a single lithium-ion battery cell reaches the full charge shunt control reference value for the first time, a portion of the solar cell subarray is shunted, the charging current is reduced, and the voltage of the single lithium-ion battery cell drops; when the voltage of a single lithium-ion battery cell reaches the full charge shunt control reference value again, a portion of the solar cell subarray or the remaining solar cell subarray is shunted again, and the charging current is further reduced until it is completely shunted.

[0030] The backup charging control circuit uses three independent lithium-ion battery pack voltage acquisition circuits 7 and three independent full-charge open-circuit control signal circuits 8 (to set the required full-charge open-circuit control reference value and compare and calculate it). After passing through a three-out-of-two voting circuit 9, the final full-charge open-circuit control signal is generated and sent to the charging control switch group 11. When the lithium-ion battery pack voltage reaches the set full-charge open-circuit control reference value, the charging control switch group 11 is driven to open the circuit to complete the full-charge control.

[0031] The charging control switch group 11 can be composed of electronic switches or magnetic latching relays, etc., to receive a full charge open-circuit control signal to realize automatic opening of the charging circuit; to receive a charging start signal to realize automatic closing of the charging circuit; and to receive remote control command signals to realize programmed opening and programmed closing of the charging circuit. A charging protection switch group 12 is set up to form a two-parallel, two-series switch combination with the charging control switch group 11, which can isolate the charging circuit from failure due to any switch malfunction.

[0032] The charging control switch group 12 is also composed of electronic switches or magnetic latching relays, etc., which receive charging protection signals to realize automatic opening of the charging circuit; and receive remote control command signals to realize programmed opening and programmed closing of the charging circuit.

[0033] The charging protection signal receives safety threshold signals from battery temperature and battery voltage. When the set temperature and voltage safety thresholds are exceeded, the charging protection switch group 12 is automatically disconnected.

[0034] Optionally, the open-circuit control reference value can be preset via a hardware comparison circuit and can be set to V. z1 V z2 V z3 For each gear, a certain dead zone interval D is set between the reference values ​​of each gear. z The maximum charging voltage setting should generally not exceed the upper limit of the safe charging voltage of a single lithium-ion battery cell. Each setting of the fully charged open-circuit control reference value should be higher than each setting of the corresponding fully charged shunt control reference value, with a voltage interval of D, i.e., the fully charged open-circuit control reference value V. z1 (V) z2 V z3 (etc.) ÷ n = full shunt control reference value V d1 (V) d2 V d3 (etc.) + D. As the battery voltage gradually rises during the charging process, it first reaches the full charge shunt control reference value, and then the main charging shunt control is prioritized, while the backup charging control provides thermal redundancy; if the main charging control fails partially or completely due to a fault and cannot perform full charging shunt, and there is still residual charging current causing the battery voltage to continue to rise, the backup charging control automatically takes over and achieves full charge control.

[0035] Optionally, the open-circuit control reference value V is filled. z1 V z2 V z3 The gear selection can be made through a hardware selection circuit based on the energy balance requirements of the spacecraft's on-orbit flight mission.

[0036] Optionally, a backup charging control circuit includes an enable / disable switch 10. When the switch is closed, the fully charged open-circuit signal output is valid; when the switch is open, the fully charged open-circuit signal output is invalid. The enable / disable switch 10 can be used to isolate circuit faults.

[0037] Optionally, a charge protection signal enable / disable switch 13 is configured. When the switch is closed, the charge protection signal output is enabled; when the switch is open, the charge protection signal output is disabled. The enable / disable switch 13 can be used to isolate circuit faults.

[0038] The heterogeneous function of the charging start-up circuit refers to the use of two start-up signals with different physical sources and opposite control logic: the shadow exit charging start-up signal and the shadow entry charging start-up signal. The shadow exit charging start-up circuit 14 collects the voltage signal of a solar cell subarray. This signal is a voltage quantity, and it serves as a marker of shadow exit when the rising edge of the solar cell subarray voltage signal exceeds a set value after the spacecraft enters the sunlight area. The shadow entry charging start-up circuit collects the current signal of a solar cell string. This signal is a current quantity, and it serves as a marker of shadow entry when the falling edge of the solar cell subarray current signal is less than a set value after the spacecraft enters the shadow area. Through an "OR" logic circuit, the charging start-up signal is formed when either start-up signal is valid, enabling automatic charging start-up of the primary charging control circuit (restoring to a non-splitting state) and automatic charging start-up of the backup charging control circuit (restoring to a closed charging loop state) for each revolution.

[0039] Optionally, an enable / disable switch 16 is configured for the output signal. When the switch is closed, the output start signal is enabled; when the switch is open, the output start signal is disabled. The enable / disable switch 16 can be used to isolate circuit faults.

[0040] Optionally, an enable / disable switch 17 is provided for the image start signal. When the switch is closed, the image start signal output is enabled; when the switch is open, the image start signal output is disabled. The enable / disable switch 16 can be used to isolate circuit faults. Example

[0041] In this embodiment, the charging control method includes at least one lithium-ion battery pack. Each lithium-ion battery pack is composed of several individual battery cells or parallel battery blocks connected in series. The battery pack is charged by a solar cell array through a charging and discharging bus.

[0042] As an example, referring to Figure 1, which is a topology diagram of the high-reliability spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy according to the present invention, the charging control is performed on one lithium-ion battery pack, which consists of 7 individual battery cells or battery parallel blocks connected in series.

[0043] The main control circuit is equipped with two individual unit voltage levels to fully charge the shunt control reference value V. d1 V d2The reference settings are 3.99V and 4.03V; the backup control circuit is set with two levels of open-circuit control reference value V for fully charged battery pack voltage. z1 V z2 The reference settings are 28.28V and 28.56V. The fully charged open-circuit control reference value V... z1 V z2 Compared to the corresponding full-load shunt control reference value V d1 V d2 High, voltage interval is 50mV, i.e., V z1 ÷ 7 = V d1 +50mV, V z2 ÷ 7 = V d2 +50mV; The exit voltage charging start-up circuit is set to an exit voltage reference setting of 6V. After the rising edge of the solar cell subarray voltage signal is greater than the set value, it determines that the spacecraft has entered the illuminated area and can reset the shunt circuit of the main charging control and the closed charging loop to start charging; The entrance current charging start-up circuit is set to an entrance current reference setting of 3A. After the falling edge of the solar cell subarray current signal is less than the set value, it determines that the spacecraft has entered the shadow area and can reset the shunt circuit of the main charging control and the closed charging loop to start charging.

[0044] As an initial state of an embodiment, the primary control circuit is filled with the shunt control reference value selected by V. d1， Backup control circuit fully charged shunt control reference value selection V z1 The open circuit signal valid / disable switch 10 is set to the "valid" state. 。 After the spacecraft moves from the shadow area into the sunlight area, the charging current of the solar cell subarray charges the lithium-ion battery pack through the charge / discharge bus, and the lithium-ion battery voltage begins to rise. When the lithium-ion battery voltage first reaches V... d1 Then, the main control circuit is triggered to implement shunt, thereby achieving main control.

[0045] Optionally, the shunt control can employ a segmented shunt method, which is beneficial for fully charging the lithium-ion battery under the same conditions. That is, the lithium-ion battery cell voltage reaches V for the first time. d1 When half of the solar cell subarray is shunted, the charging current is reduced by half, and the voltage of the individual lithium-ion battery cells drops; when the voltage of the individual lithium-ion battery cells reaches V again during the charging process... d1 Then, the remaining half of the solar cell subarray is shunted, reducing the charging current to full shunting. Further optimization can be achieved by setting the reference voltage for the second shunting slightly greater than V. d1， But less than V z1 This further increases the secondary charging capacity and avoids the effects of voltage fluctuations. In this embodiment, the reference voltage for the second shunt is set to 4.01V.

[0046] Under normal operating conditions, the backup control circuit acts as a hot redundancy / hot backup and does not participate in control. If the primary charging control fails partially or completely due to a fault and cannot fully shunt the charging current, residual charging current will still cause the battery voltage to continue rising. When the battery pack voltage reaches V... z1 When the backup control circuit is triggered, it will open the charging circuit to achieve full charge control of the backup.

[0047] As an example, based on the evaluation results of ground tests, the primary control circuit V d1 When selecting 3.99V, under standard environmental conditions of 20℃, the fully charged capacity after two-stage shunt charging is approximately 103%~105% of the rated capacity; in the backup control circuit V z1 When selecting 4.04V, under standard environmental conditions at 20℃, the fully charged capacity is approximately 106%~108% of the rated capacity. The fully charged capacities of the main and backup charging controls are basically equivalent, both meeting the usage requirements. A higher reference voltage setting results in a higher fully charged capacity, but it should generally not exceed the upper limit of the safe charging voltage for a single lithium-ion battery cell (reference value 4.15V), and sufficient margin should be maintained between it and the charging protection voltage setting (reference value 4.20V).

[0048] The above embodiments are merely illustrative of the technical concept and features of the present invention, intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A highly reliable spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy, wherein the lithium-ion battery is composed of several individual battery cells or parallel blocks connected in series, the lithium-ion battery receives current from a solar array for charging, and is used to power spacecraft loads, characterized in that... include: The charging control system consists of two heterogeneous and thermally redundant charging control circuits: a primary charging control circuit and a backup charging control circuit. Automatic cyclic charging is achieved through a charging start-up circuit, which also consists of two heterogeneous and thermally redundant charging control circuits.

2. The high-reliability spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy as described in claim 1, characterized in that, The functional heterogeneity of the charging control circuit refers to the combination of two completely different charging control methods used in the primary and backup charging control circuits. Specifically, the primary charging control circuit adopts a full current shunting control method, while the backup charging control circuit adopts an open-circuit control method.

3. The high-reliability spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy as described in claim 2, characterized in that, The thermal redundancy of the charging control circuit means that both the primary and backup charging control circuits are effective on duty. As the battery voltage gradually rises during the charging process, the primary function takes priority to achieve full charge control. When the primary function fails partially or completely due to a fault, the backup function automatically takes over to achieve full charge control. The fault handling process does not rely on software judgment or manual decision-making intervention.

4. The high-reliability spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy as described in claim 1, characterized in that, The functional heterogeneity of the charging start-up circuit refers to the use of two start-up signals with different physical sources and opposite control logic, namely, the output voltage source charging start-up signal and the input current source charging start-up signal.

5. The high-reliability spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy as described in claim 1, characterized in that, The thermal redundancy of the charging start circuit means that charging can be automatically started as long as any charging start signal is valid.

6. The high-reliability spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy as described in claim 3, characterized in that, The primary charging control circuit is prioritized and effective, while the backup charging control circuit serves as a hot redundancy backup. The primary fully charged current shunt control reference is preset and multiple levels are selected through a hardware comparison circuit, with a certain dead interval set between each reference level. The backup full-charge open-circuit control reference is also preset and selected through a hardware comparison circuit, with a certain dead zone interval set between each reference. Each level of the full-charge open-circuit control reference is higher than each level of the corresponding full-charge shunt control reference, with a certain voltage interval set.

7. The high-reliability spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy as described in claim 6, characterized in that, The gear position for full shunt control reference is selected through a hardware selection circuit based on the energy balance requirements of the spacecraft's on-orbit flight mission.

8. The high-reliability spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy as described in claim 6, characterized in that, The maximum setting of the open-circuit control reference does not exceed the upper limit of the safe charging voltage of a single lithium-ion battery cell.

9. The high-reliability spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy as described in claim 4, characterized in that, For the shading charging start signal, the shading charging start circuit collects the voltage signal of a solar cell subarray. This signal is a voltage quantity. When the rising edge of the solar cell subarray voltage signal exceeds a set value after the spacecraft enters the sunlit area, it serves as the shading indicator. For the shading charging start signal, the shading charging start circuit collects the current signal of a solar cell string. This signal is a current quantity. When the spacecraft enters the shadow area, the falling edge of the solar cell subarray current signal is less than a set value, which serves as the shading indicator.

10. The high-reliability spacecraft lithium-ion battery charging control method with functional heterogeneous thermal redundancy as described in claim 3, characterized in that, As the battery voltage gradually rises during the charging process, it first reaches the full charge shunt control reference value, and then the main charging shunt control is prioritized, while the backup charging control provides thermal redundancy. If the main charging control fails partially or completely due to a fault and cannot perform full charging shunt, and there is still residual charging current causing the battery voltage to continue to rise, the backup charging control automatically takes over and achieves full charge control.

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