Battery over-temperature protection method and system for battery swap cabinet two-wheeled vehicle
By collecting battery information and setting personalized parameters, combined with minute-level and second-level monitoring modes, the charging current is dynamically adjusted, which solves the fire risk caused by battery overheating in the battery swapping cabinet and improves safety and efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- FUJIAN NEBULA ELECTRONICS CO LTD
- Filing Date
- 2025-09-28
- Publication Date
- 2026-07-07
Smart Images
Figure CN121291201B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of battery safety management technology for battery swapping cabinets, and specifically to a method and system for overheat protection of batteries in two-wheeled vehicles using battery swapping cabinets. Background Technology
[0002] With the rapid development of the food delivery industry, the number of delivery workers has surged, and two-wheeled electric vehicles (hereinafter referred to as "two-wheelers") have become the mainstream delivery mode. However, due to the limited size and structure of two-wheelers, their batteries usually have limited capacity, resulting in insufficient range and requiring frequent charging. Battery swapping, with its advantage of rapid energy replenishment, provides an effective solution to range anxiety. Therefore, battery swapping stations specifically designed for two-wheeler batteries have emerged.
[0003] Existing battery swapping cabinets face a significant safety challenge during operation: the risk of fire caused by battery overheating increases significantly when charging a large number of densely packed batteries simultaneously. This is primarily due to inherent flaws in the protection mechanisms of existing technologies:
[0004] 1. Inadequate handling of individual battery differences: Batteries of different brands and at different stages of aging exhibit significant differences in thermal stability, while existing systems generally employ a uniform temperature protection threshold. This can lead to unreasonable limitations on the charging efficiency of new batteries, while aging batteries with reduced thermal stability may experience thermal runaway due to delayed protection.
[0005] 2. Limited Temperature Dynamic Response Mechanism: Most mainstream protection measures rely on passive heat dissipation (such as fans) or simple power-off strategies based on a single fixed threshold. Such solutions cannot effectively identify and distinguish the pattern of battery temperature rise (such as slow or rapid temperature rise), and are prone to protection malfunctions (frequent interruptions of normal charging) or protection failures (failure to prevent dangerous temperature rises in time).
[0006] 3. Poor real-time temperature monitoring: Most existing solutions rely on minute-level temperature sampling and monitoring frequencies, which makes it difficult to capture minute-level temperature jumps that may occur inside the battery (such as instantaneous temperature rise caused by internal short circuits), resulting in the inability to trigger effective protection at critical moments.
[0007] Therefore, how to provide a method and system for overheat protection of two-wheeled vehicle batteries in battery swapping cabinets to improve the safety of charging in battery swapping cabinets has become an urgent technical problem to be solved. Summary of the Invention
[0008] The technical problem to be solved by the present invention is to provide a method and system for over-temperature protection of batteries in two-wheeled vehicles using a battery swapping cabinet, thereby improving the safety of charging in the battery swapping cabinet.
[0009] In a first aspect, the present invention provides a method for over-temperature protection of batteries in a battery swapping cabinet for two-wheeled vehicles, comprising the following steps:
[0010] Step S1: The battery swapping cabinet collects a large amount of battery information, classifies the batteries based on the battery information, and sets corresponding temperature warning values, SOC upper limit, first current reduction ratio, second current reduction ratio, first temperature rise rate threshold, second temperature rise rate threshold, duration threshold, and current increase step for each category of battery.
[0011] Step S2: The battery swapping cabinet performs charging operations on each battery based on a preset initial charging current. During the charging process, the temperature value and real-time SOC of each battery are collected in real time based on a preset sampling frequency, and the temperature rise rate is calculated in real time based on the temperature value.
[0012] Step S3: When the temperature value is less than the temperature warning value and the temperature rise rate is less than or equal to the first temperature rise rate threshold, the minute-level monitoring mode is triggered to perform continuous monitoring in minutes.
[0013] Step S4: When the temperature value is greater than or equal to the temperature warning value, or the temperature rise rate is greater than the second temperature rise rate threshold, a second-level monitoring mode is triggered to continuously monitor the temperature in seconds. The initial charging current is dynamically adjusted based on a three-level current control strategy to reduce the charging current, and the battery is charged based on the reduced charging current.
[0014] Step S5: Based on the temperature rise rate, duration threshold, and current increase step, perform a current recovery operation on the reduced charging current;
[0015] Step S6: Execute fuse protection based on the number of triggers of the three-level current regulation strategy;
[0016] Step S7: When the real-time SOC reaches the upper limit of SOC, stop charging the battery.
[0017] Furthermore, in step S1, the battery information includes at least the battery brand, battery model, battery type, battery usage time, and battery capacity.
[0018] The temperature warning value ranges from [40℃, 60℃]; the SOC upper limit ranges from [80%, 100%]; the first current reduction ratio ranges from [5%, 10%]; the second current reduction ratio ranges from [15%, 30%]; the first temperature rise rate threshold is 1℃ / min; the second temperature rise rate threshold is 3℃ / min; the duration threshold is 5 seconds; and the current boost step is 0.1A / 30S.
[0019] Furthermore, in step S4, the three-level current regulation strategy specifically includes:
[0020] When 0.5℃ / min < temperature rise rate ≤ 1℃ / min, it is a gradual rise stage, and the charging current reduction = initial charging current * (1 - first current reduction ratio);
[0021] When 1℃ / min < temperature rise rate ≤ 3℃ / min, it is the linear rapid rise stage, and the charging current reduction = initial charging current * (1 - second current reduction ratio);
[0022] When the temperature rise rate is >3℃ / min, it is in the nonlinear acceleration stage. The charging current is reduced to 0.5A and continuously monitored in seconds. If the temperature rise rate is still >3℃ / min, the charging current is reduced to 0A.
[0023] Furthermore, step S5 specifically includes:
[0024] When the reduced charging current is 0.5A, continuous monitoring is performed in seconds to determine whether the temperature rise rate is ≤1℃ / min and whether the duration meets the threshold. If not, the reduced charging current is set to 0A; if yes, then:
[0025] The charging current is gradually increased and reduced according to the current increase steps. When the reduced charging current is equal to 80% of the initial charging current, or the real-time SOC is equal to the upper limit of SOC, the current recovery operation of the reduced charging current is stopped.
[0026] Furthermore, step S6 specifically includes:
[0027] If the number of times the nonlinear acceleration phase of the three-level current regulation strategy is triggered during a single charge of the same battery exceeds a preset threshold, then the fuse protection is executed, the charging of the corresponding battery is permanently stopped, and an alarm is pushed; otherwise, monitoring continues.
[0028] Secondly, the present invention provides a battery swapping cabinet over-temperature protection system for two-wheeled vehicles, comprising the following modules:
[0029] The threshold parameter setting module is used to collect a large amount of battery information from the battery swapping cabinet, classify the batteries based on the battery information, and set corresponding temperature warning values, SOC upper limit, first current reduction ratio, second current reduction ratio, first temperature rise rate threshold, second temperature rise rate threshold, duration threshold, and current increase step for each category of battery.
[0030] The charging data acquisition module is used by the battery swapping cabinet to perform charging operations on each battery based on a preset initial charging current. During the charging process, the temperature value and real-time SOC of each battery are collected in real time based on a preset sampling frequency, and the temperature rise rate is calculated in real time based on the temperature value.
[0031] The minute-level monitoring module is used to trigger the minute-level monitoring mode when the temperature value is less than the temperature warning value and the temperature rise rate is less than or equal to the first temperature rise rate threshold, and to perform continuous monitoring in minutes.
[0032] The second-level monitoring module is used to trigger the second-level monitoring mode when the temperature value is greater than or equal to the temperature warning value, or the temperature rise rate is greater than the second temperature rise rate threshold. It continuously monitors the temperature in seconds and dynamically adjusts the initial charging current based on the three-level current regulation strategy to reduce the charging current, and charges the battery based on the reduced charging current.
[0033] The current recovery module is used to perform a current recovery operation on the reduced charging current based on the temperature rise rate, duration threshold, and current boost step.
[0034] The fuse protection module is used to perform fuse protection based on the number of triggers of the three-level current regulation strategy;
[0035] The charging stop module is used to stop charging the battery when the real-time SOC reaches the upper limit of SOC.
[0036] Furthermore, in the threshold parameter setting module, the battery information includes at least the battery brand, battery model, battery type, battery usage time, and battery capacity.
[0037] The temperature warning value ranges from [40℃, 60℃]; the SOC upper limit ranges from [80%, 100%]; the first current reduction ratio ranges from [5%, 10%]; the second current reduction ratio ranges from [15%, 30%]; the first temperature rise rate threshold is 1℃ / min; the second temperature rise rate threshold is 3℃ / min; the duration threshold is 5 seconds; and the current boost step is 0.1A / 30S.
[0038] Furthermore, in the second-level monitoring module, the three-level current regulation strategy specifically includes:
[0039] When 0.5℃ / min < temperature rise rate ≤ 1℃ / min, it is a gradual rise stage, and the charging current reduction = initial charging current * (1 - first current reduction ratio);
[0040] When 1℃ / min < temperature rise rate ≤ 3℃ / min, it is the linear rapid rise stage, and the charging current reduction = initial charging current * (1 - second current reduction ratio);
[0041] When the temperature rise rate is >3℃ / min, it is in the nonlinear acceleration stage. The charging current is reduced to 0.5A and continuously monitored in seconds. If the temperature rise rate is still >3℃ / min, the charging current is reduced to 0A.
[0042] Furthermore, the current recovery module is specifically used for:
[0043] When the reduced charging current is 0.5A, continuous monitoring is performed in seconds to determine whether the temperature rise rate is ≤1℃ / min and whether the duration meets the threshold. If not, the reduced charging current is set to 0A; if yes, then:
[0044] The charging current is gradually increased and reduced according to the current increase steps. When the reduced charging current is equal to 80% of the initial charging current, or the real-time SOC is equal to the upper limit of SOC, the current recovery operation of the reduced charging current is stopped.
[0045] Furthermore, the fuse protection module is specifically used for:
[0046] If the number of times the nonlinear acceleration phase of the three-level current regulation strategy is triggered during a single charge of the same battery exceeds a preset threshold, then the fuse protection is executed, the charging of the corresponding battery is permanently stopped, and an alarm is pushed; otherwise, monitoring continues.
[0047] The advantages of this invention are:
[0048] 1. By collecting a large amount of battery information, batteries are classified. For each category, corresponding temperature warning values, SOC upper limits, first current reduction ratios, second current reduction ratios, first temperature rise rate thresholds, second temperature rise rate thresholds, duration thresholds, and current boost steps are set. Then, the battery swapping cabinet performs charging operations on each battery based on a preset initial charging current. During charging, the temperature value and real-time SOC of each battery are collected in real time based on a preset sampling frequency, and the temperature rise rate is calculated in real time based on the temperature value. When the temperature value is lower than the temperature warning value and the temperature rise rate is less than or equal to the first temperature rise rate threshold, a minute-level monitoring mode is triggered. When the temperature value is greater than or equal to the temperature warning value, or the temperature rise rate is greater than the second temperature rise rate threshold, a second-level monitoring mode is triggered, and the initial charging current is dynamically adjusted based on a three-level current control strategy to obtain a reduced charging current. The battery is then charged based on this reduced charging current. Finally, based on the temperature rise rate, duration threshold, and current boost step, a current recovery operation is performed on the reduced charging current, using the three-level current control strategy... The system triggers a circuit breaker protection mechanism, stopping battery charging when the real-time State of Charge (SOC) reaches its upper limit. This involves classifying batteries by collecting individual information such as brand and model, customizing temperature warning values and SOC upper limits for different battery categories to avoid limiting charging of new batteries or delaying protection for aging batteries due to uniform thresholds. A multi-level dynamic response mechanism is also implemented: minute-level monitoring is used under normal conditions, automatically switching to second-level monitoring when the temperature exceeds the warning value or the temperature rise rate is too high. A three-level current control strategy (proportionally reducing current or lowering it to a safe current based on temperature rise ranges of 0.5-1℃ / min, 1-3℃ / min, and >3℃ / min) precisely matches different risk levels of temperature rise patterns, preventing accidental interruptions due to slight temperature rises and rapidly reducing current or even triggering a circuit breaker for rapid temperature rises. Furthermore, after the risk is mitigated, the current is gradually restored in steps, combined with repeated triggering of circuit breaker protection for extreme temperature rises, ultimately achieving full-process protection from risk identification and dynamic suppression to a safety net, greatly improving the safety of battery swapping station charging.
[0049] 2. Based on temperature value and temperature rise rate as dual indicators, different monitoring frequencies (minute-level / second-level) are triggered, and a three-level current control strategy is set. The minute-level monitoring mode (temperature < warning value and temperature rise ≤ 1℃ / min) reduces the system load and is suitable for safe conditions. The second-level monitoring mode (temperature ≥ warning value or temperature rise > 3℃ / min) is combined with dynamic current reduction (5%~30%) to quickly suppress the thermal runaway trend, which solves the problem of delayed response to sudden temperature rise in traditional fixed frequency monitoring and adapts to the needs of different thermal risk stages of the battery.
[0050] 3. Based on historical battery data (brand, model, capacity, etc.), pre-classify and differentiate parameters (such as SOC upper limit, current reduction ratio) to achieve personalized protection thresholds. For example, ternary lithium batteries can be set with a lower temperature warning value (such as 40℃), while lithium iron phosphate batteries can be relaxed to 50℃, avoiding false protection or insufficient protection caused by a "one-size-fits-all" approach; and effectively extending battery life. By limiting the upper limit of SOC (adjustable from 80% to 100%), electrolyte decomposition caused by full charging is reduced, the number of cycles is increased, and the limitations of fixed parameters in traditional battery swapping cabinets are broken, achieving safe compatibility of "one cabinet for multiple vehicle models of batteries".
[0051] 4. The system is divided into three stages based on the temperature rise rate: gradual, linear, and nonlinear. A current recovery logic is designed to achieve precise current reduction. In the gradual stage, the current is reduced by only 5% to 10%, while in the nonlinear stage, the current is directly limited to 0.5A or even 0A to avoid excessive current reduction affecting charging efficiency. The system also achieves intelligent current recovery. After the temperature rise is ≤1℃ / min and lasts for 5 seconds, the current is increased in steps of 0.1A / 30S until 80% of the initial current or the SOC limit is reached. This ensures that the system does not blindly recover before the risk is eliminated. This solves the problems of low efficiency of passive BMS balancing and high cost of active balancing. The system achieves an optimized balance between safety and performance through software strategies.
[0052] 5. Count the number of times the "non-linear acceleration stage" is triggered in a single charge. If the number of triggers exceeds the threshold, the battery will be permanently blown and an alarm will be triggered. In other words, for hidden faults such as aging batteries or internal micro short circuits, the battery will be forcibly shut down after multiple triggers of severe temperature rise to avoid thermal runaway. Alarms will be pushed in conjunction with the battery, allowing maintenance personnel to replace faulty batteries in a timely manner. This integrates the entire battery life cycle management into the charging process and further improves the safety of the battery swapping cabinet.
[0053] 6. All thresholds are limited to scientifically defined ranges (e.g., temperature warning value 40–60℃, SOC upper limit 80–100%); the temperature warning value is higher than normal temperature (25℃) but lower than the thermal runaway critical point (usually >80℃), with a safety buffer reserved; the temperature rise rate threshold uses 1℃ / min (level 1) and 3℃ / min (level 2) to cover common fault models.
[0054] 7. By innovatively constructing a battery safety adaptive protection system, this system dynamically collects battery data and sets differentiated protection parameters based on different categories. Combined with a minute-level / second-level dual-mode monitoring mechanism driven by the temperature rise rate, it performs three-level gradient current regulation in real time during charging (5%~30% dynamic current limiting, 0.5A emergency suppression, and 0A fuse protection). Based on stable temperature rise conditions, it intelligently restores the current to a safe threshold. At the same time, it relies on a single-charge fuse counting mechanism to block the cumulative risk of aging batteries. Finally, it achieves a closed-loop safety protection for multi-brand batteries through software algorithms. Its core advantage lies in subverting the passive response logic of traditional hardware over-temperature protection. While ensuring high compatibility (adapting to batteries of different brands / aging states), it significantly reduces over-temperature risk and improves charging efficiency.
[0055] 8. Dynamically adjusting current through temperature rise mode avoids "one-size-fits-all" power outages, reducing charging interruption rates; in non-linear acceleration scenarios, the 0.5A buffer current design reduces false shutdowns and achieves precise protection; second-level response ensures thermal runaway prevention time is ≤3 seconds (compared to 15 seconds in traditional solutions), effectively reducing the accident rate; the fuse mechanism identifies high-risk batteries, effectively reducing over-temperature faults and improving safety performance; current step recovery reduces power loss and increases the average daily charging capacity of a single battery; SOC upper limit hierarchical management extends the life of older batteries; supports real-time data upload to the cloud; supports operators to batch optimize threshold parameters, thereby effectively improving operational efficiency; differentiated threshold parameters adapt to batteries with different aging levels, such as setting a lower first current reduction ratio and a higher second current reduction ratio for older batteries, effectively reducing over-temperature fault rates; dynamic switching of dual-frequency mode reduces CPU load, effectively reducing power consumption; minute-level filtering suppresses false triggers, effectively reducing invalid power outages. Attached Figure Description
[0056] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0057] Fig. 1 This is a flowchart of a method for overheat protection of a battery in a two-wheeled vehicle using a battery swapping cabinet, according to the present invention.
[0058] Fig. 2 This is a schematic diagram of the structure of a battery swapping cabinet for overheat protection of batteries in two-wheeled vehicles according to the present invention. Detailed Implementation
[0059] The technical solution in this application embodiment follows the general idea as follows: By collecting and classifying individual battery information such as battery brand and model, key parameters such as temperature warning values and SOC upper limits are customized for different battery categories to avoid limiting charging of new batteries or delaying protection of aging batteries due to uniform thresholds. Simultaneously, a multi-level dynamic response mechanism is constructed—normally using minute-level monitoring, automatically switching to second-level monitoring when the temperature exceeds the temperature warning value or the temperature rise rate is too high. Based on a three-level current control strategy (reducing current proportionally or reducing it to a safe current according to temperature rise ranges of 0.5-1℃ / min, 1-3℃ / min, and >3℃ / min respectively), different temperature rise modes with varying degrees of danger are precisely matched. This prevents false interruptions due to slight temperature rises and rapidly reduces current or even causes fuse failure in cases of rapid temperature rises. Furthermore, after the risk is mitigated, the current is gradually restored in steps, combined with repeated triggering of fuse protection against extreme temperature rises, ultimately achieving full-process protection from risk identification and dynamic suppression to safety safeguards, thereby improving the safety of battery swapping cabinet charging.
[0060] Please refer to Figs. 1-2 As shown, a preferred embodiment of the battery over-temperature protection method for two-wheeled vehicles using a battery swapping cabinet according to the present invention includes the following steps:
[0061] Step S1: The battery swapping cabinet collects a large amount of battery information, classifies the batteries based on the battery information, and sets corresponding temperature warning values, SOC upper limit, first current reduction ratio, second current reduction ratio, first temperature rise rate threshold, second temperature rise rate threshold, duration threshold, and current increase step for each category of battery.
[0062] Step S2: The battery swapping cabinet performs charging operations on each battery based on a preset initial charging current. During the charging process, the temperature value and real-time SOC of each battery are collected in real time based on a preset sampling frequency, and the temperature rise rate is calculated in real time based on the temperature value.
[0063] Step S3: When the temperature value is less than the temperature warning value and the temperature rise rate is less than or equal to the first temperature rise rate threshold, the minute-level monitoring mode is triggered (the long-term smooth temperature rise rate is calculated at a frequency of ≤0.017Hz) to continuously monitor in minutes.
[0064] Step S4: When the temperature value is greater than or equal to the temperature warning value, or the temperature rise rate is greater than the second temperature rise rate threshold, a second-level monitoring mode is triggered (the short-term temperature rise rate is calculated at a frequency of ≥1Hz (time window ≤3 seconds)). Continuous monitoring is performed in seconds, and the initial charging current is dynamically adjusted based on the three-level current control strategy to obtain a reduced charging current. The battery is charged based on the reduced charging current.
[0065] Step S5: Based on the temperature rise rate, duration threshold, and current increase step, perform a current recovery operation on the reduced charging current;
[0066] Step S6: Execute fuse protection based on the number of triggers of the three-level current regulation strategy;
[0067] Step S7: When the real-time SOC reaches the upper limit of SOC, stop charging the battery (regardless of temperature status).
[0068] Based on the dual indicators of temperature value and temperature rise rate, different monitoring frequencies (minute-level / second-level) are triggered, and a three-level current regulation strategy is set. The minute-level monitoring mode (temperature < warning value and temperature rise ≤ 1℃ / min) reduces the system load and is suitable for safe conditions. The second-level monitoring mode (temperature ≥ warning value or temperature rise > 3℃ / min) is combined with dynamic current reduction (5%~30%) to quickly suppress the thermal runaway trend, which solves the problem of the lag in response to sudden temperature rise in traditional fixed frequency monitoring and adapts to the needs of different thermal risk stages of the battery.
[0069] In step S1, the battery information includes at least the battery brand, battery model, battery type, battery usage time, and battery capacity.
[0070] The temperature warning value ranges from [40℃, 60℃]; the SOC upper limit ranges from [80%, 100%]; the first current reduction ratio ranges from [5%, 10%]; the second current reduction ratio ranges from [15%, 30%]; the first temperature rise rate threshold is 1℃ / min; the second temperature rise rate threshold is 3℃ / min; the duration threshold is 5 seconds; and the current boost step is 0.1A / 30S.
[0071] Based on historical battery data (brand, model, capacity, etc.), pre-classification and differentiated parameter settings (such as SOC upper limit and current reduction ratio) are implemented to achieve personalized protection thresholds. For example, a lower temperature warning value (such as 40℃) can be set for ternary lithium batteries, while it can be relaxed to 50℃ for lithium iron phosphate batteries, avoiding false protection or insufficient protection caused by a "one-size-fits-all" approach. It also effectively extends battery life by limiting the upper limit of SOC (adjustable from 80% to 100%), reducing electrolyte decomposition caused by full charging, increasing the number of cycles, breaking through the limitations of fixed parameters in traditional battery swapping cabinets, and achieving safe compatibility of "one cabinet for batteries of multiple models".
[0072] All thresholds are limited to scientifically defined ranges (e.g., temperature warning value 40–60℃, SOC upper limit 80–100%); the temperature warning value is higher than normal temperature (25℃) but lower than the thermal runaway critical point (usually >80℃) to reserve a safety buffer; the temperature rise rate threshold uses 1℃ / min (level 1) and 3℃ / min (level 2) to cover common fault models.
[0073] In step S4, the three-level current regulation strategy is specifically as follows:
[0074] When 0.5℃ / min < temperature rise rate ≤ 1℃ / min, it is a gradual rise stage, and the charging current reduction = initial charging current * (1 - first current reduction ratio);
[0075] When 1℃ / min < temperature rise rate ≤ 3℃ / min, it is the linear rapid rise stage, and the charging current reduction = initial charging current * (1 - second current reduction ratio);
[0076] When the temperature rise rate is >3℃ / min, it is in the nonlinear acceleration stage. The charging current is reduced to 0.5A and continuously monitored in seconds. If the temperature rise rate is still >3℃ / min, the charging current is reduced to 0A (power off).
[0077] The system is divided into three stages based on the temperature rise rate: gradual, linear, and nonlinear. A current recovery logic is designed to achieve precise current reduction. In the gradual stage, the current is reduced by only 5% to 10%, while in the nonlinear stage, the current is directly limited to 0.5A or even 0A to avoid excessive current reduction affecting charging efficiency. It also achieves intelligent current recovery. After the temperature rise is ≤1℃ / min and lasts for 5 seconds, the current is increased in steps of 0.1A / 30S until 80% of the initial current or the SOC limit is reached. This ensures that the current is not blindly restored before the risk is eliminated. This solves the problems of low efficiency of passive BMS balancing and high cost of active balancing. The system achieves an optimized balance between safety and performance through software strategies.
[0078] Step S5 specifically involves:
[0079] When the reduced charging current is 0.5A, continuous monitoring is performed in seconds to determine whether the temperature rise rate is ≤1℃ / min and whether the duration threshold is met (since the duration threshold is 5 seconds, and continuous monitoring is performed in seconds, i.e., 5 consecutive second-level sampling judgments). If not, the reduced charging current is set to 0A; if yes, then:
[0080] The charging current is gradually increased and reduced according to the current increase steps. When the reduced charging current is equal to 80% of the initial charging current, or the real-time SOC is equal to the upper limit of SOC, the current recovery operation of the reduced charging current is stopped.
[0081] Step S6 specifically involves:
[0082] The system determines whether the number of times the nonlinear acceleration phase of the three-level current regulation strategy is triggered during a single charge cycle for the same battery exceeds a preset threshold. If so, it executes fuse protection, permanently stopping the charging of the corresponding battery and sending an alarm; otherwise, it continues monitoring. The threshold can be set as needed, for example, to 3 times.
[0083] The system counts the number of times the "non-linear acceleration phase" is triggered during a single charge. If the number of triggers exceeds a certain threshold, the battery will permanently melt and trigger an alarm. This means that for hidden faults such as aging batteries or internal micro-short circuits, the system will force the battery to shut down after multiple triggers of severe temperature rise to prevent thermal runaway. Alarms will be pushed to the system to support maintenance personnel in replacing faulty batteries in a timely manner. This integrates the entire battery lifecycle management into the charging process, further improving the safety of the battery swapping cabinet.
[0084] By innovatively constructing a battery safety adaptive protection system, dynamically collecting battery data and classifying and setting differentiated protection parameters, combined with a minute-level / second-level dual-mode monitoring mechanism driven by temperature rise rate, the system performs three-level gradient current regulation in real time during charging (5%~30% dynamic current limiting, 0.5A emergency suppression, and 0A fuse protection), and intelligently restores the current to a safe threshold based on stable temperature rise conditions. At the same time, relying on a single-charge fuse counting mechanism to block the cumulative risk of aging batteries, the system ultimately achieves a closed-loop safety protection for multi-brand batteries through software algorithms. The core advantage lies in subverting the passive response logic of traditional hardware over-temperature protection, significantly reducing over-temperature risk and improving charging efficiency while ensuring high compatibility (adapting to batteries of different brands / aging states).
[0085] A preferred embodiment of the battery swapping cabinet over-temperature protection system for two-wheeled vehicles according to the present invention includes the following modules:
[0086] The threshold parameter setting module is used to collect a large amount of battery information from the battery swapping cabinet, classify the batteries based on the battery information, and set corresponding temperature warning values, SOC upper limit, first current reduction ratio, second current reduction ratio, first temperature rise rate threshold, second temperature rise rate threshold, duration threshold, and current increase step for each category of battery.
[0087] The charging data acquisition module is used by the battery swapping cabinet to perform charging operations on each battery based on a preset initial charging current. During the charging process, the temperature value and real-time SOC of each battery are collected in real time based on a preset sampling frequency, and the temperature rise rate is calculated in real time based on the temperature value.
[0088] The minute-level monitoring module is used to trigger the minute-level monitoring mode (calculating the long-term smooth temperature rise rate at a frequency of ≤0.017Hz) when the temperature value is less than the temperature warning value and the temperature rise rate is less than or equal to the first temperature rise rate threshold, and to perform continuous monitoring in minutes.
[0089] The second-level monitoring module is used to trigger the second-level monitoring mode (calculate the short-time temperature rise rate at a frequency of ≥1Hz (time window ≤3 seconds)) when the temperature value is greater than or equal to the temperature warning value, or the temperature rise rate is greater than the second temperature rise rate threshold. It continuously monitors the temperature rise rate in seconds and dynamically adjusts the initial charging current based on the three-level current control strategy to reduce the charging current. The battery is then charged based on the reduced charging current.
[0090] The current recovery module is used to perform a current recovery operation on the reduced charging current based on the temperature rise rate, duration threshold, and current boost step.
[0091] The fuse protection module is used to perform fuse protection based on the number of triggers of the three-level current regulation strategy;
[0092] The stop charging module is used to stop charging the battery (regardless of temperature status) when the real-time SOC reaches the upper limit of SOC.
[0093] Based on the dual indicators of temperature value and temperature rise rate, different monitoring frequencies (minute-level / second-level) are triggered, and a three-level current regulation strategy is set. The minute-level monitoring mode (temperature < warning value and temperature rise ≤ 1℃ / min) reduces the system load and is suitable for safe conditions. The second-level monitoring mode (temperature ≥ warning value or temperature rise > 3℃ / min) is combined with dynamic current reduction (5%~30%) to quickly suppress the thermal runaway trend, which solves the problem of the lag in response to sudden temperature rise in traditional fixed frequency monitoring and adapts to the needs of different thermal risk stages of the battery.
[0094] In the threshold parameter setting module, the battery information includes at least the battery brand, battery model, battery type, battery usage time, and battery capacity.
[0095] The temperature warning value ranges from [40℃, 60℃]; the SOC upper limit ranges from [80%, 100%]; the first current reduction ratio ranges from [5%, 10%]; the second current reduction ratio ranges from [15%, 30%]; the first temperature rise rate threshold is 1℃ / min; the second temperature rise rate threshold is 3℃ / min; the duration threshold is 5 seconds; and the current boost step is 0.1A / 30S.
[0096] Based on historical battery data (brand, model, capacity, etc.), pre-classification and differentiated parameter settings (such as SOC upper limit and current reduction ratio) are implemented to achieve personalized protection thresholds. For example, a lower temperature warning value (such as 40℃) can be set for ternary lithium batteries, while it can be relaxed to 50℃ for lithium iron phosphate batteries, avoiding false protection or insufficient protection caused by a "one-size-fits-all" approach. It also effectively extends battery life by limiting the upper limit of SOC (adjustable from 80% to 100%), reducing electrolyte decomposition caused by full charging, increasing the number of cycles, breaking through the limitations of fixed parameters in traditional battery swapping cabinets, and achieving safe compatibility of "one cabinet for batteries of multiple models".
[0097] All thresholds are limited to scientifically defined ranges (e.g., temperature warning value 40–60℃, SOC upper limit 80–100%); the temperature warning value is higher than normal temperature (25℃) but lower than the thermal runaway critical point (usually >80℃) to reserve a safety buffer; the temperature rise rate threshold uses 1℃ / min (level 1) and 3℃ / min (level 2) to cover common fault models.
[0098] In the second-level monitoring module, the three-level current regulation strategy is specifically as follows:
[0099] When 0.5℃ / min < temperature rise rate ≤ 1℃ / min, it is a gradual rise stage, and the charging current reduction = initial charging current * (1 - first current reduction ratio);
[0100] When 1℃ / min < temperature rise rate ≤ 3℃ / min, it is the linear rapid rise stage, and the charging current reduction = initial charging current * (1 - second current reduction ratio);
[0101] When the temperature rise rate is >3℃ / min, it is in the nonlinear acceleration stage. The charging current is reduced to 0.5A and continuously monitored in seconds. If the temperature rise rate is still >3℃ / min, the charging current is reduced to 0A (power off).
[0102] The system is divided into three stages based on the temperature rise rate: gradual, linear, and nonlinear. A current recovery logic is designed to achieve precise current reduction. In the gradual stage, the current is reduced by only 5% to 10%, while in the nonlinear stage, the current is directly limited to 0.5A or even 0A to avoid excessive current reduction affecting charging efficiency. It also achieves intelligent current recovery. After the temperature rise is ≤1℃ / min and lasts for 5 seconds, the current is increased in steps of 0.1A / 30S until 80% of the initial current or the SOC limit is reached. This ensures that the current is not blindly restored before the risk is eliminated. This solves the problems of low efficiency of passive BMS balancing and high cost of active balancing. The system achieves an optimized balance between safety and performance through software strategies.
[0103] The current recovery module is specifically used for:
[0104] When the reduced charging current is 0.5A, continuous monitoring is performed in seconds to determine whether the temperature rise rate is ≤1℃ / min and whether the duration threshold is met (since the duration threshold is 5 seconds, and continuous monitoring is performed in seconds, i.e., 5 consecutive second-level sampling judgments). If not, the reduced charging current is set to 0A; if yes, then:
[0105] The charging current is gradually increased and reduced according to the current increase steps. When the reduced charging current is equal to 80% of the initial charging current, or the real-time SOC is equal to the upper limit of SOC, the current recovery operation of the reduced charging current is stopped.
[0106] The fuse protection module is specifically used for:
[0107] The system determines whether the number of times the nonlinear acceleration phase of the three-level current regulation strategy is triggered during a single charge cycle for the same battery exceeds a preset threshold. If so, it executes fuse protection, permanently stopping the charging of the corresponding battery and sending an alarm; otherwise, it continues monitoring. The threshold can be set as needed, for example, to 3 times.
[0108] The system counts the number of times the "non-linear acceleration phase" is triggered during a single charge. If the number of triggers exceeds a certain threshold, the battery will permanently melt and trigger an alarm. This means that for hidden faults such as aging batteries or internal micro-short circuits, the system will force the battery to shut down after multiple triggers of severe temperature rise to prevent thermal runaway. Alarms will be pushed to the system to support maintenance personnel in replacing faulty batteries in a timely manner. This integrates the entire battery lifecycle management into the charging process, further improving the safety of the battery swapping cabinet.
[0109] By innovatively constructing a battery safety adaptive protection system, dynamically collecting battery data and classifying and setting differentiated protection parameters, combined with a minute-level / second-level dual-mode monitoring mechanism driven by temperature rise rate, the system performs three-level gradient current regulation in real time during charging (5%~30% dynamic current limiting, 0.5A emergency suppression, and 0A fuse protection), and intelligently restores the current to a safe threshold based on stable temperature rise conditions. At the same time, relying on a single-charge fuse counting mechanism to block the cumulative risk of aging batteries, the system ultimately achieves a closed-loop safety protection for multi-brand batteries through software algorithms. The core advantage lies in subverting the passive response logic of traditional hardware over-temperature protection, significantly reducing over-temperature risk and improving charging efficiency while ensuring high compatibility (adapting to batteries of different brands / aging states).
[0110] In summary, the advantages of this invention are:
[0111] 1. By collecting a large amount of battery information, batteries are classified. For each category, corresponding temperature warning values, SOC upper limits, first current reduction ratios, second current reduction ratios, first temperature rise rate thresholds, second temperature rise rate thresholds, duration thresholds, and current boost steps are set. Then, the battery swapping cabinet performs charging operations on each battery based on a preset initial charging current. During charging, the temperature value and real-time SOC of each battery are collected in real time based on a preset sampling frequency, and the temperature rise rate is calculated in real time based on the temperature value. When the temperature value is lower than the temperature warning value and the temperature rise rate is less than or equal to the first temperature rise rate threshold, a minute-level monitoring mode is triggered. When the temperature value is greater than or equal to the temperature warning value, or the temperature rise rate is greater than the second temperature rise rate threshold, a second-level monitoring mode is triggered, and the initial charging current is dynamically adjusted based on a three-level current control strategy to obtain a reduced charging current. The battery is then charged based on this reduced charging current. Finally, based on the temperature rise rate, duration threshold, and current boost step, a current recovery operation is performed on the reduced charging current, using the three-level current control strategy... The system triggers a circuit breaker protection mechanism, stopping battery charging when the real-time State of Charge (SOC) reaches its upper limit. This involves classifying batteries by collecting individual information such as brand and model, customizing temperature warning values and SOC upper limits for different battery categories to avoid limiting charging of new batteries or delaying protection for aging batteries due to uniform thresholds. A multi-level dynamic response mechanism is also implemented: minute-level monitoring is used under normal conditions, automatically switching to second-level monitoring when the temperature exceeds the warning value or the temperature rise rate is too high. A three-level current control strategy (proportionally reducing current or lowering it to a safe current based on temperature rise ranges of 0.5-1℃ / min, 1-3℃ / min, and >3℃ / min) precisely matches different risk levels of temperature rise patterns, preventing accidental interruptions due to slight temperature rises and rapidly reducing current or even triggering a circuit breaker for rapid temperature rises. Furthermore, after the risk is mitigated, the current is gradually restored in steps, combined with repeated triggering of circuit breaker protection for extreme temperature rises, ultimately achieving full-process protection from risk identification and dynamic suppression to a safety net, greatly improving the safety of battery swapping station charging.
[0112] 2. Based on temperature value and temperature rise rate as dual indicators, different monitoring frequencies (minute-level / second-level) are triggered, and a three-level current control strategy is set. The minute-level monitoring mode (temperature < warning value and temperature rise ≤ 1℃ / min) reduces the system load and is suitable for safe conditions. The second-level monitoring mode (temperature ≥ warning value or temperature rise > 3℃ / min) is combined with dynamic current reduction (5%~30%) to quickly suppress the thermal runaway trend, which solves the problem of delayed response to sudden temperature rise in traditional fixed frequency monitoring and adapts to the needs of different thermal risk stages of the battery.
[0113] 3. Based on historical battery data (brand, model, capacity, etc.), pre-classify and differentiate parameters (such as SOC upper limit, current reduction ratio) to achieve personalized protection thresholds. For example, ternary lithium batteries can be set with a lower temperature warning value (such as 40℃), while lithium iron phosphate batteries can be relaxed to 50℃, avoiding false protection or insufficient protection caused by a "one-size-fits-all" approach; and effectively extending battery life. By limiting the upper limit of SOC (adjustable from 80% to 100%), electrolyte decomposition caused by full charging is reduced, the number of cycles is increased, and the limitations of fixed parameters in traditional battery swapping cabinets are broken, achieving safe compatibility of "one cabinet for multiple vehicle models of batteries".
[0114] 4. The system is divided into three stages based on the temperature rise rate: gradual, linear, and nonlinear. A current recovery logic is designed to achieve precise current reduction. In the gradual stage, the current is reduced by only 5% to 10%, while in the nonlinear stage, the current is directly limited to 0.5A or even 0A to avoid excessive current reduction affecting charging efficiency. The system also achieves intelligent current recovery. After the temperature rise is ≤1℃ / min and lasts for 5 seconds, the current is increased in steps of 0.1A / 30S until 80% of the initial current or the SOC limit is reached. This ensures that the system does not blindly recover before the risk is eliminated. This solves the problems of low efficiency of passive BMS balancing and high cost of active balancing. The system achieves an optimized balance between safety and performance through software strategies.
[0115] 5. Count the number of times the "non-linear acceleration stage" is triggered in a single charge. If the number of triggers exceeds the threshold, the battery will be permanently blown and an alarm will be triggered. In other words, for hidden faults such as aging batteries or internal micro short circuits, the battery will be forcibly shut down after multiple triggers of severe temperature rise to avoid thermal runaway. Alarms will be pushed in conjunction with the battery, allowing maintenance personnel to replace faulty batteries in a timely manner. This integrates the entire battery life cycle management into the charging process and further improves the safety of the battery swapping cabinet.
[0116] 6. All thresholds are limited to scientifically defined ranges (e.g., temperature warning value 40–60℃, SOC upper limit 80–100%); the temperature warning value is higher than normal temperature (25℃) but lower than the thermal runaway critical point (usually >80℃), with a safety buffer reserved; the temperature rise rate threshold uses 1℃ / min (level 1) and 3℃ / min (level 2) to cover common fault models.
[0117] 7. By innovatively constructing a battery safety adaptive protection system, this system dynamically collects battery data and sets differentiated protection parameters based on different categories. Combined with a minute-level / second-level dual-mode monitoring mechanism driven by the temperature rise rate, it performs three-level gradient current regulation in real time during charging (5%~30% dynamic current limiting, 0.5A emergency suppression, and 0A fuse protection). Based on stable temperature rise conditions, it intelligently restores the current to a safe threshold. At the same time, it relies on a single-charge fuse counting mechanism to block the cumulative risk of aging batteries. Finally, it achieves a closed-loop safety protection for multi-brand batteries through software algorithms. Its core advantage lies in subverting the passive response logic of traditional hardware over-temperature protection. While ensuring high compatibility (adapting to batteries of different brands / aging states), it significantly reduces over-temperature risk and improves charging efficiency.
[0118] 8. Dynamically adjusting current through temperature rise mode avoids "one-size-fits-all" power outages, reducing charging interruption rates; in non-linear acceleration scenarios, the 0.5A buffer current design reduces false shutdowns and achieves precise protection; second-level response ensures thermal runaway prevention time is ≤3 seconds (compared to 15 seconds in traditional solutions), effectively reducing the accident rate; the fuse mechanism identifies high-risk batteries, effectively reducing over-temperature faults and improving safety performance; current step recovery reduces power loss and increases the average daily charging capacity of a single battery; SOC upper limit hierarchical management extends the life of older batteries; supports real-time data upload to the cloud; supports operators to batch optimize threshold parameters, thereby effectively improving operational efficiency; differentiated threshold parameters adapt to batteries with different aging levels, such as setting a lower first current reduction ratio and a higher second current reduction ratio for older batteries, effectively reducing over-temperature fault rates; dynamic switching of dual-frequency mode reduces CPU load, effectively reducing power consumption; minute-level filtering suppresses false triggers, effectively reducing invalid power outages.
[0119] While specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments described are merely illustrative and not intended to limit the scope of the present invention. Equivalent modifications and variations made by those skilled in the art in accordance with the spirit of the present invention should be covered within the scope of protection of the claims of the present invention.
Claims
1. A method for over-temperature protection of batteries in two-wheeled vehicles using a battery swapping cabinet, characterized in that: Includes the following steps: Step S1: The battery swapping cabinet collects battery information, classifies the batteries based on the battery information, and sets corresponding temperature warning values, SOC upper limit, first current reduction ratio, second current reduction ratio, first temperature rise rate threshold, second temperature rise rate threshold, duration threshold, and current increase step for each category of battery. Step S2: The battery swapping cabinet performs charging operations on each battery based on a preset initial charging current. During the charging process, the temperature value and real-time SOC of each battery are collected in real time based on a preset sampling frequency, and the temperature rise rate is calculated in real time based on the temperature value. Step S3: When the temperature value is less than the temperature warning value and the temperature rise rate is less than or equal to the first temperature rise rate threshold, the minute-level monitoring mode is triggered to perform continuous monitoring in minutes. Step S4: When the temperature value is greater than or equal to the temperature warning value, or the temperature rise rate is greater than the second temperature rise rate threshold, a second-level monitoring mode is triggered to continuously monitor the temperature in seconds. The initial charging current is dynamically adjusted based on a three-level current control strategy to reduce the charging current, and the battery is charged based on the reduced charging current. Step S5: Based on the temperature rise rate, duration threshold, and current increase step, perform a current recovery operation on the reduced charging current; Step S6: Execute fuse protection based on the number of triggers of the three-level current regulation strategy; Step S7: When the real-time SOC reaches the upper limit of SOC, stop charging the battery.
2. The method for over-temperature protection of a battery in a battery swapping cabinet for two-wheeled vehicles as described in claim 1, characterized in that: In step S1, the battery information includes at least the battery brand, battery model, battery type, battery usage time, and battery capacity. The temperature warning value ranges from [40℃, 60℃]; the SOC upper limit ranges from [80%, 100%]; the first current reduction ratio ranges from [5%, 10%]; the second current reduction ratio ranges from [15%, 30%]; the first temperature rise rate threshold is 1℃ / min; the second temperature rise rate threshold is 3℃ / min; the duration threshold is 5 seconds; and the current boost step is 0.1A / 30S.
3. The method for over-temperature protection of a battery in a battery swapping cabinet for two-wheeled vehicles as described in claim 1, characterized in that: In step S4, the three-level current regulation strategy is specifically as follows: When 0.5℃ / min < temperature rise rate ≤ 1℃ / min, it is a gradual rise stage, and the charging current reduction = initial charging current * (1 - first current reduction ratio). When 1℃ / min < temperature rise rate ≤ 3℃ / min, it is the linear rapid rise stage, and the charging current reduction = initial charging current * (1 - second current reduction ratio). When the temperature rise rate is >3℃ / min, it is in the nonlinear acceleration stage. The charging current is reduced to 0.5A and continuously monitored in seconds. If the temperature rise rate is still >3℃ / min, the charging current is reduced to 0A.
4. The method for over-temperature protection of a battery in a battery swapping cabinet for two-wheeled vehicles as described in claim 1, characterized in that: Step S5 specifically involves: When the reduced charging current is 0.5A, continuous monitoring is performed in seconds to determine whether the temperature rise rate is ≤1℃ / min and whether the duration meets the threshold. If not, the reduced charging current is set to 0A; if yes, then: The charging current is gradually increased and reduced according to the current increase steps. When the reduced charging current = initial charging current * 80%, or the real-time SOC = upper limit of SOC, the current recovery operation of the reduced charging current is stopped.
5. The method for over-temperature protection of a battery in a battery swapping cabinet for two-wheeled vehicles as described in claim 1, characterized in that: Step S6 specifically involves: If the number of times the nonlinear acceleration phase of the three-level current regulation strategy is triggered during a single charge of the same battery exceeds a preset threshold, then the fuse protection is executed, the charging of the corresponding battery is permanently stopped, and an alarm is pushed; otherwise, monitoring continues.
6. A battery swapping cabinet for two-wheeled vehicles with over-temperature protection system, characterized in that: Includes the following modules: The threshold parameter setting module is used to collect battery information in the battery swapping cabinet, classify the batteries based on the battery information, and set corresponding temperature warning value, SOC upper limit, first current reduction ratio, second current reduction ratio, first temperature rise rate threshold, second temperature rise rate threshold, duration threshold and current increase step for each category of battery. The charging data acquisition module is used by the battery swapping cabinet to perform charging operations on each battery based on a preset initial charging current. During the charging process, the temperature value and real-time SOC of each battery are collected in real time based on a preset sampling frequency, and the temperature rise rate is calculated in real time based on the temperature value. The minute-level monitoring module is used to trigger the minute-level monitoring mode when the temperature value is less than the temperature warning value and the temperature rise rate is less than or equal to the first temperature rise rate threshold, and to perform continuous monitoring in minutes. The second-level monitoring module is used to trigger the second-level monitoring mode when the temperature value is greater than or equal to the temperature warning value, or the temperature rise rate is greater than the second temperature rise rate threshold. It continuously monitors the temperature in seconds and dynamically adjusts the initial charging current based on the three-level current regulation strategy to reduce the charging current, and charges the battery based on the reduced charging current. The current recovery module is used to perform a current recovery operation on the reduced charging current based on the temperature rise rate, duration threshold, and current boost step. The fuse protection module is used to perform fuse protection based on the number of triggers of the three-level current regulation strategy; The charging stop module is used to stop charging the battery when the real-time SOC reaches the upper limit of SOC.
7. The battery over-temperature protection system for a two-wheeled vehicle battery swapping cabinet as described in claim 6, characterized in that: In the threshold parameter setting module, the battery information includes at least the battery brand, battery model, battery type, battery usage time, and battery capacity. The temperature warning value ranges from [40℃, 60℃]; the SOC upper limit ranges from [80%, 100%]; the first current reduction ratio ranges from [5%, 10%]; the second current reduction ratio ranges from [15%, 30%]; the first temperature rise rate threshold is 1℃ / min; the second temperature rise rate threshold is 3℃ / min; the duration threshold is 5 seconds; and the current boost step is 0.1A / 30S.
8. The battery over-temperature protection system for a two-wheeled vehicle battery swapping cabinet as described in claim 6, characterized in that: In the second-level monitoring module, the three-level current regulation strategy is specifically as follows: When 0.5℃ / min < temperature rise rate ≤ 1℃ / min, it is a gradual rise stage, and the charging current reduction = initial charging current * (1 - first current reduction ratio). When 1℃ / min < temperature rise rate ≤ 3℃ / min, it is the linear rapid rise stage, and the charging current reduction = initial charging current * (1 - second current reduction ratio). When the temperature rise rate is >3℃ / min, it is in the nonlinear acceleration stage. The charging current is reduced to 0.5A and continuously monitored in seconds. If the temperature rise rate is still >3℃ / min, the charging current is reduced to 0A.
9. The battery over-temperature protection system for a two-wheeled vehicle battery swapping cabinet as described in claim 6, characterized in that: The current recovery module is specifically used for: When the reduced charging current is 0.5A, continuous monitoring is performed in seconds to determine whether the temperature rise rate is ≤1℃ / min and whether the duration meets the threshold. If not, the reduced charging current is set to 0A; if yes, then: The charging current is gradually increased and reduced according to the current increase steps. When the reduced charging current = initial charging current * 80%, or the real-time SOC = upper limit of SOC, the current recovery operation of the reduced charging current is stopped.
10. The battery over-temperature protection system for a two-wheeled vehicle battery swapping station as described in claim 6, characterized in that: The fuse protection module is specifically used for: If the number of times the nonlinear acceleration phase of the three-level current regulation strategy is triggered during a single charge of the same battery exceeds a preset threshold, then the fuse protection is executed, the charging of the corresponding battery is permanently stopped, and an alarm is pushed; otherwise, monitoring continues.