Battery pack collision detection system

Abstract

According to the battery pack collision detection system, a plurality of pressure detection units arranged on a battery pack are used for collecting pressure values, and a collision judgment module is used for judging whether the pressure values collected by the pressure detection units are larger than a pressure threshold value or not and whether the change rate of the pressure values is larger than a set change rate or not; when it is judged that the pressure value collected by any pressure detection unit is larger than the pressure threshold value and the change rate of the pressure value is larger than the set change rate, it is judged that the battery pack collides. Therefore, according to the battery pack collision detection system, when it is judged that the pressure value collected by any pressure detection unit is larger than the pressure threshold value and the change rate of the pressure value is larger than the set change rate, it is judged that the battery pack is collided, the collision detection accuracy is improved, and the false alarm rate is reduced; the technical problem of poor collision detection accuracy in the prior art is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery packs, and in particular, relates to a battery pack collision detection system. Background Art

[0002] As the power source of new energy electric equipment, battery pack safety monitoring is particularly important.

[0003] The basic architecture of the battery management system (BMS) includes an AFE analog front end (such as TI BQ76952), a main control MCU (such as N32WB031), and a communication module (485 / 4G module) to achieve SOC estimation and overcharge / over-discharge protection.

[0004] Traditional BMS only has the function of monitoring electrochemical parameters (voltage / current / temperature), lacks physical collision detection, and cannot sense the physical impact (such as falling, collision) on the battery pack, resulting in continued operation after structural damage and causing thermal runaway.

[0005] Currently, existing technologies typically use a single triaxial accelerometer mounted on the battery pack to detect collisions and trigger a power outage when the acceleration exceeds a fixed threshold. However, single-sensor detection is susceptible to interference from environmental vibrations, resulting in a false trigger rate exceeding 15% under complex operating conditions, a high false alarm rate, and poor detection accuracy. Summary of the Invention

[0006] The present invention provides a battery pack collision detection system, which solves the technical problem of poor collision detection accuracy in the prior art.

[0007] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0008] Battery pack collision detection system, including:

[0009] A pressure detection module, comprising a plurality of pressure detection units disposed on the battery pack, the pressure detection units being used to collect pressure values;

[0010] The collision judgment module is used to judge whether the pressure value collected by the pressure detection unit is greater than the pressure threshold and whether the rate of change of the pressure value is greater than the set rate of change; when it is judged that the pressure value collected by any pressure detection unit is greater than the pressure threshold and the rate of change of the pressure value is greater than the set rate of change, a collision is determined to have occurred.

[0011] In some embodiments of the present application, the multiple pressure detection units are distributed around and on the bottom of the battery pack.

[0012] In some embodiments of the present application, the collision judgment module is also used to: when it is determined that the pressure value collected by any pressure detection unit is greater than the pressure threshold and the change rate of the pressure value is greater than the set change rate, start timing; if the pressure value is greater than the pressure threshold for more than a first set time period, it is determined that a collision has occurred.

[0013] In some embodiments of the present application, the collision judgment module is further used to: calculate the average value and standard deviation of the pressure values ​​collected by each pressure detection unit every second set time period, and calculate the pressure threshold; the pressure threshold is the sum of the average value and three times the standard deviation.

[0014] In some embodiments of the present application, the collision judgment module is further configured to: after determining that a collision has occurred, judge the collision level based on the pressure value.

[0015] In some embodiments of the present application, the determination of the collision level based on the pressure value specifically includes:

[0016] If the pressure value is within the first set pressure range, the collision level is determined to be a level one collision;

[0017] If the pressure value is within the second set pressure range, the collision level is determined to be a level 2 collision;

[0018] If the pressure value is within the third set pressure range, the collision level is determined to be a level three collision;

[0019] Wherein, any value within the first set pressure range is smaller than any value within the second set pressure range; and any value within the second set pressure range is smaller than any value within the third set pressure range.

[0020] In some embodiments of the present application, the collision judgment module is further configured to:

[0021] When the collision level is determined to be a level one collision, a local warning is issued and collision information is recorded locally. The collision information includes the collision time, pressure value, pressure detection unit number, and collision level;

[0022] When the collision level is determined to be a level 2 collision, the battery pack is controlled to operate at limited power and an alarm message is sent to the cloud platform;

[0023] When the collision level is determined to be a level three collision, the battery pack is fused for protection and the location information of the battery pack is sent to the cloud platform.

[0024] In some embodiments of the present application, the collision judgment module is further configured to:

[0025] Before determining whether the pressure value collected by the pressure detection unit is greater than the pressure threshold, the pressure value collected by the pressure detection unit is filtered.

[0026] In some embodiments of the present application, the collision judgment module is further configured to:

[0027] Before determining whether the pressure value collected by the pressure detection unit is greater than the pressure threshold, the pressure value collected by the pressure detection unit is filtered and temperature compensated.

[0028] In some embodiments of the present application, the temperature compensation formula is: P_real=P_measured+k*(T-T0);

[0029] in,

[0030] P_real is the pressure value after compensation; P_measured is the pressure value collected by the pressure detection unit;

[0031] T is the current temperature; T0 is the calibration reference temperature; k is the temperature compensation coefficient.

[0032] Compared with the prior art, the advantages and positive effects of the present invention are as follows: the battery pack collision detection system of the present invention collects pressure values ​​through multiple pressure detection units arranged on the battery pack, and the collision judgment module is used to determine whether the pressure values ​​collected by the pressure detection units are greater than the pressure threshold and whether the rate of change of the pressure values ​​is greater than the set rate of change; when it is determined that the pressure value collected by any pressure detection unit is greater than the pressure threshold and the rate of change of the pressure value is greater than the set rate of change, the battery pack is determined to have collided. Therefore, the battery pack collision detection system of this embodiment determines that the battery pack has collided only when it is determined that the pressure value collected by any pressure detection unit is greater than the pressure threshold and the rate of change of the pressure value is greater than the set rate of change, thereby improving the accuracy of collision detection, reducing the false alarm rate, and solving the technical problem of poor collision detection accuracy in the prior art.

[0033] Other features and advantages of the present invention will become more apparent after reading the detailed description of the embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0035] Figure 1 This is a structural block diagram of an embodiment of a battery pack collision detection system proposed by the present invention;

[0036] Figure 2is a flow chart of an embodiment of the steps executed by the battery pack collision detection system proposed in the present invention;

[0037] Figure 3 is a system block diagram of another embodiment of the battery pack collision detection system proposed by the present invention;

[0038] Figure 4 This is a flowchart of another embodiment of the steps executed by the battery pack collision detection system proposed in the present invention. DETAILED DESCRIPTION

[0039] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0040] It should be noted that in the description of the present invention, terms such as "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. These are merely for ease of description and do not indicate or imply that the device or component described must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0041] Furthermore, it should be noted that, in the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0042] The battery pack collision detection system of this embodiment includes a pressure detection module, a collision judgment module, etc. Figure 1 shown.

[0043] The pressure detection module includes a plurality of pressure detection units arranged on the battery pack, and the pressure detection units are used to collect pressure values ​​and send the collected pressure values ​​to the collision detection module.

[0044] The collision judgment module is used to judge whether the pressure value collected by the pressure detection unit is greater than the pressure threshold and whether the rate of change of the pressure value is greater than the set rate of change; when it is judged that the pressure value collected by any pressure detection unit is greater than the pressure threshold and the rate of change of the pressure value is greater than the set rate of change, a collision is determined to have occurred.

[0045] The battery pack collision detection system of this embodiment specifically performs the following steps, see Figure 2 shown.

[0046] Step S1: Multiple pressure detection units arranged on the battery pack collect pressure values ​​and send them to the collision judgment module.

[0047] Step S2: The collision judgment module determines whether the pressure value collected by the pressure detection unit is greater than the pressure threshold, and whether the change rate of the pressure value is greater than the set change rate.

[0048] If so, that is, it is determined that the pressure value collected by any pressure detection unit is greater than the pressure threshold, and the change rate of the pressure value is greater than the set change rate, step S3 is executed.

[0049] Step S3: Determine whether the battery pack has collided.

[0050] The pressure detection unit sends the collected pressure value to the collision judgment module. When the collision judgment module determines that the pressure value collected by any pressure detection unit is greater than the pressure threshold and the change rate of the pressure value is greater than the set change rate, it determines that the battery pack has collided.

[0051] Structural damage to the battery pack is only possible when the pressure exceeds the threshold. If the battery pack is impacted or dropped, the pressure will rise sharply in a very short period of time, and the rate of change of the pressure will exceed the set rate of change. Normal use or gradual pressure increase will not result in such a high rate of change.

[0052] When the pressure value is greater than the pressure threshold, it indicates that the pressure value is relatively high; when the rate of change of the pressure value is greater than the set rate of change, it indicates that the pressure value is changing rapidly. Only when both "the pressure value is large enough" and "the pressure rises rapidly enough" are met is it considered a true collision event. This can further filter out chronic pressure changes (such as the slow stacking of heavy objects) and occasional noise, greatly reducing false alarm rates and improving collision detection accuracy.

[0053] The battery pack collision detection system of this embodiment collects pressure values ​​through multiple pressure detection units arranged on the battery pack. The collision judgment module is used to determine whether the pressure values ​​collected by the pressure detection units are greater than a pressure threshold and whether the rate of change of the pressure values ​​is greater than a set rate of change. When it is determined that the pressure value collected by any pressure detection unit is greater than the pressure threshold and the rate of change of the pressure value is greater than the set rate of change, the battery pack is determined to have collided. Therefore, the battery pack collision detection system of this embodiment only determines that the battery pack has collided when it is determined that the pressure value collected by any pressure detection unit is greater than the pressure threshold and the rate of change of the pressure value is greater than the set rate of change. This improves the accuracy of collision detection and reduces the false alarm rate, thus solving the technical problem of poor collision detection accuracy in the prior art.

[0054] In some embodiments of the present application, the pressure detection unit is a thin film pressure sensor.

[0055] Thin film pressure sensors, such as the RX-D2025 sensor, convert pressure signals into 0-5V analog signals through the piezoresistive effect, with a range of 50kg and a response time of <1ms.

[0056] In some embodiments of the present application, multiple pressure detection units are distributed around and on the bottom of the battery pack, so that the pressure on the battery pack in various directions can be detected, collision positioning can be achieved, the accuracy of collision detection can be further improved, and maintenance can be facilitated.

[0057] For example, the pressure detection module includes five pressure detection units, four of which are arranged on the four sides of the battery pack, and another pressure detection unit is arranged at the bottom of the battery pack, thereby achieving collision positioning.

[0058] By designing a multi-sensor array layout, five thin-film pressure sensors (RX-D2025) are deployed around and on the bottom of the battery pack to form a spatially distributed detection network to achieve collision positioning.

[0059] In some other embodiments of the present application, the pressure detection module includes a piezoelectric array flexible sensor, which includes a plurality of piezoelectric sensors arranged in an array. A single flexible sensor covers the entire battery surface, simplifying installation.

[0060] In some embodiments of the present application, the collision judgment module is also used to: when it is determined that the pressure value collected by any pressure detection unit is greater than the pressure threshold and the change rate of the pressure value is greater than the set change rate, start timing; if the pressure value is greater than the pressure threshold for more than a first set time (such as the first set time is 20ms), it is determined that a collision has occurred.

[0061] Therefore, when the pressure value is greater than the pressure threshold and the rate of change of the pressure value is greater than the set rate of change, timing starts. If the pressure value continues to be greater than the pressure threshold for longer than the first set time, it is determined that the battery pack has collided, so as to further improve the accuracy of collision detection.

[0062] In some embodiments of the present application, the collision judgment module is further used to: calculate the average value and standard deviation of the pressure values ​​collected by each pressure detection unit every second set time period, and calculate the pressure threshold; the pressure threshold is the sum of the average value and three times the standard deviation.

[0063] Therefore, the pressure threshold is updated every second set time to achieve a dynamic pressure threshold to further improve the accuracy of collision detection. Of course, when calculating the average and standard deviation, pressure values ​​greater than the current pressure threshold are excluded.

[0064] For example, the average value and standard deviation of the pressure values ​​collected by each pressure detection unit are calculated every 30 seconds, and the pressure threshold is updated.

[0065] In some embodiments of the present application, the collision judgment module is further used to: filter the pressure value collected by the pressure detection unit before determining whether the pressure value collected by the pressure detection unit is greater than the pressure threshold.

[0066] By filtering the collected pressure values, transient noise can be effectively suppressed and the stability and accuracy of collision determination can be improved.

[0067] In some other embodiments of the present application, the collision judgment module is further used to: filter and temperature compensate the pressure value collected by the pressure detection unit before determining whether the pressure value collected by the pressure detection unit is greater than the pressure threshold.

[0068] By filtering the collected pressure values, transient noise can be effectively suppressed. By performing temperature compensation on the pressure values, the impact of temperature changes on pressure detection can be compensated, thus improving the accuracy of collision detection.

[0069] In some embodiments of the present application, a moving average filter is performed on the pressure value collected by the pressure detection unit to effectively suppress transient noise and improve the stability of collision determination.

[0070] In some other embodiments of the present application, Kalman filtering is performed on the pressure values ​​collected by the pressure detection unit to improve the noise suppression capability.

[0071] The output of the pressure detection unit may drift or produce errors in different temperature environments. In order to compensate for the impact of temperature changes on pressure detection, the output of the pressure detection unit needs to be temperature compensated. The purpose is to ensure the accuracy of pressure detection in the full temperature range of -20℃ to 60℃, so that the detection error is less than 3%.

[0072] The output signal of a pressure detection unit (such as the RX-D2025 pressure sensor) will shift (temperature drift) at different temperatures due to changes in material properties. If not compensated, pressure readings in low or high temperature environments will exhibit systematic errors, affecting the accuracy of collision detection.

[0073] Through experimental calibration, we can determine the zero point and sensitivity variations of the pressure detection unit (pressure sensor) at different temperatures. Assuming the output of the pressure detection unit is linearly related to temperature, compensation can be performed using the following formula.

[0074] In some embodiments of the present application, the temperature compensation formula is: P_real=P_measured+k*(T-T0).

[0075] Among them, P_real is the pressure value after compensation;

[0076] P_measured is the pressure value collected by the pressure detection unit, which is the measurement value of the pressure detection unit;

[0077] T is the current temperature;

[0078] T0 is the calibration reference temperature, which is a preset fixed value; for example, 25°C.

[0079] k is the temperature compensation coefficient. The temperature compensation coefficient k can be obtained through multi-temperature point calibration at the factory (obtained through experimental calibration) or dynamically fine-tuned during system operation.

[0080] During each pressure acquisition, the current temperature is read simultaneously (using the MCU's built-in temperature sensor or an external temperature sensor). The measured value of each pressure detection unit is corrected according to the compensation formula.

[0081] By using the above temperature compensation formula, the pressure value P_measured measured by the pressure detection unit is compensated through the current temperature T, the calibration reference temperature T0, and the temperature compensation coefficient k to obtain a relatively accurate compensated pressure value P_real.

[0082] After temperature compensation, the error of pressure detection in the range of -20℃ to 60℃ can be controlled within 3%, significantly improving the environmental adaptability and detection reliability of the system.

[0083] Therefore, the collision judgment module filters and temperature compensates the pressure value collected by the pressure detection unit, and then determines whether the pressure value collected by the pressure detection unit is greater than the pressure threshold and whether the change rate of the pressure value is greater than the set change rate.

[0084] The collision judgment module first filters and temperature compensates the pressure value collected by each pressure detection unit, and then calculates the average value and standard deviation of the pressure value collected by each pressure detection unit every second set time to update the pressure threshold.

[0085] In some embodiments of the present application, the collision judgment module is further configured to: after determining that a collision has occurred, judge the collision level based on the pressure value.

[0086] The collision level is determined based on the pressure value, so that users can easily know the degree of collision of the battery pack.

[0087] In some embodiments of the present application, the collision level is determined based on the pressure value, specifically including:

[0088] If the pressure value is within the first set pressure range, the collision level is determined to be a level one collision (mild collision);

[0089] If the pressure value is within the second set pressure range, the collision level is determined to be a secondary collision (moderate collision);

[0090] If the pressure value is within the third set pressure range, the collision level is determined to be a level three collision (severe collision);

[0091] Among them, any value in the first set pressure range is smaller than any value in the second set pressure range, and any value in the second set pressure range is smaller than any value in the third set pressure range.

[0092] The collision level is divided into three levels according to the pressure range to which the pressure value belongs. The division is simple and convenient for users to know the collision degree of the battery pack.

[0093] In some embodiments of the present application, the collision determination module is further configured to perform the following operations:

[0094] If the collision level is determined to be a level 1 collision (mild collision), a local warning (such as a buzzer warning) is issued and collision information is recorded locally. The collision information includes the collision time, pressure value, pressure detection unit number, collision level, etc.

[0095] If the collision level is determined to be a Level 2 collision (moderate collision), the battery pack is controlled to operate at limited power and an alarm message is sent to the cloud platform;

[0096] When the collision level is determined to be a level three collision (severe collision), the battery pack is fused for protection (battery pack output is cut off) and the battery pack location information is sent to the cloud platform.

[0097] A three-level response mechanism is implemented based on the three collision levels to improve the safety of the battery pack.

[0098] For example, the first set pressure range is [25kg, 35kg), the second set pressure range is [35kg, 45kg), and the third set pressure range is [45kg, +∞).

[0099] When the pressure value ∈ [25kg, 35kg), the collision level is a mild collision, the collision information is recorded locally, and a buzzer is sounded for warning;

[0100] When the pressure value ∈ [35kg, 45kg), the collision level is moderate, the battery pack operates at limited power, and a cloud alarm is issued;

[0101] When the pressure value ∈[45kg, +∞), the collision level is severe, the battery pack is fused for protection, and the GPS positioning reports the location of the battery pack.

[0102] Existing collision protection devices only shut down the power supply after detecting a collision. They lack a tiered response strategy, fail to distinguish between minor collisions and serious accidents, and have a single response mechanism. This application, however, implements a three-tiered response mechanism (local warning / power limiting / fusing) based on the pressure value, achieving a balance between safety and availability.

[0103] In some other embodiments of the present application, the pressure detection unit may be a MEMS accelerometer, and the drop impact is detected through three-axis acceleration.

[0104] Next, combine Figure 3 and Figure 4 , specifically explain the specific workflow of the battery pack collision detection system of this application.

[0105] The battery pack collision detection system includes a sensing layer (i.e., pressure detection module), a processing layer, an algorithm layer, and an execution layer. Figure 3 Among them, the processing layer and the algorithm layer are integrated into the collision judgment module.

[0106] Sensing layer (i.e. pressure detection module): 5 RX-D2025 sensors (4 sensors are arranged around the battery pack, and 1 sensor is arranged at the bottom of the battery pack), connected to the adapter board through FPC cables.

[0107] Processing layer: The N32WB031 chip completes ADC acquisition, collects the pressure values ​​measured by 5 sensors (5-channel polling, sampling rate 1kHz), and continues preliminary processing of the data, including moving average filtering and temperature compensation.

[0108] Algorithm layer: Updates dynamic pressure thresholds, collision determination, and three-level response; simultaneously communicates with the cloud (4G EC200U module) to report pressure values ​​and status data to the cloud platform.

[0109] Execution layer: After the MCU on the BMS protection board receives the results of algorithm processing, it controls charging and discharging (MOSFET control) by calling the API interface.

[0110] The specific process of the core algorithm, such as Figure 4 As shown, it mainly includes core functions such as multi-channel pressure data filtering, dynamic threshold adaptation, collision event judgment and graded response, etc. The specific descriptions are as follows:

[0111] (1) Sensor data acquisition.

[0112] The system uses five pressure sensors (RX-D2025) distributed around the battery pack and on its bottom to collect real-time pressure data at a sampling rate of 1kHz. This raw data reflects the external forces acting on the battery pack in different directions and locations.

[0113] (2) Moving average filtering and temperature compensation.

[0114] The collected raw pressure data first undergoes a moving average filter. This step smoothes the signal, suppresses ambient noise and occasional interference, and ensures the accuracy of subsequent judgments. The filter window length is set based on the sampling rate and actual operating conditions.

[0115] Multi-channel moving average filtering: Each pressure sensor channel maintains a circular buffer that stores the most recent N sample values. Each time new data is acquired, it is added to the buffer and the average of all sample values ​​is calculated as the current smoothed pressure value. This effectively suppresses transient noise and improves judgment stability.

[0116] After the moving average filtering is completed, temperature compensation is performed.

[0117] (3) Dynamic threshold determination.

[0118] After filtering and temperature compensation, the pressure data is compared to the dynamic pressure threshold. This threshold is updated in real time based on the historical mean (μ) and standard deviation (σ) of each sensor. The dynamic pressure threshold = μ + 3σ. The judgment criteria are: the pressure value P is greater than the dynamic pressure threshold (e.g., the dynamic pressure threshold is 20.6 kg) and the pressure change rate dP / dt is greater than the set change rate (e.g., 80 kg / s). This mechanism adapts to different environments and operating conditions, significantly reducing false alarm rates.

[0119] Dynamic baseline and threshold adaptation: The system periodically (e.g., every 30 seconds) collects statistics on the pressure data of each pressure sensor channel, updates its baseline mean (μ) and standard deviation (σ), and dynamically adjusts the pressure threshold (μ + 3σ) accordingly. This process automatically excludes data during periods of high pressure (i.e., pressure values ​​greater than the pressure threshold), ensuring baseline accuracy and robustness.

[0120] The dynamic pressure threshold calculation based on the baseline mean (μ) and standard deviation (σ) is combined with the gradient threshold (i.e., the set change rate, such as 80kg / s) to perform dual judgment and improve the accuracy of collision detection.

[0121] μ (mean) and σ (standard deviation) are parameters commonly used in statistics to describe the distribution characteristics of a set of data. μ+3σ is a classic method for dynamic threshold determination, representing "the mean plus three times the standard deviation." Under a normal distribution, 99.7% of data will fall within the range of μ±3σ. Data outside this range are generally considered "anomalies" or "sudden events."

[0122] In this application, the pressure threshold is dynamically adjusted by real-time statistics of μ and σ for each pressure sensor. The pressure threshold is μ + 3σ. An abnormal impact or collision is only considered to have occurred when the pressure value P exceeds μ + 3σ and dP / dt exceeds the set rate of change. This effectively suppresses false alarms caused by environmental noise and normal fluctuations. dP / dt represents the rate of change of pressure.

[0123] For example, the dynamic pressure threshold is 20.6 kg, and the change rate is set to 80 kg / s. When the pressure value P>20.6 kg and dP / dt>80 kg / s, it is determined that the battery pack has collided and caused structural damage.

[0124] (4) Level 3 collision determination.

[0125] Once the pressure value is detected to exceed the dynamic pressure threshold and the pressure value change rate is greater than the set change rate, the system enters the collision classification judgment phase. According to the size of the pressure peak, the collision event is divided into three levels:

[0126] When the pressure value ∈ [25kg, 35kg), it is judged as a mild collision;

[0127] When the pressure value ∈ [35kg, 45kg), it is determined to be a moderate collision;

[0128] When the pressure value ∈[45kg, +∞), it is determined to be a severe collision.

[0129] (5) Graded response measures.

[0130] Mild collision (25-35kg): The system issues a local warning (such as a buzzer prompt) and records the event data for subsequent tracing.

[0131] Moderate collision (35-45kg): The system limits the battery pack output power and uploads alarm information to the cloud via the 4G module for remote monitoring and management.

[0132] Severe collision (>45kg): The system immediately executes fuse protection, cuts off the battery pack output, and synchronously reports the accident information and location to the cloud platform via GPS positioning to facilitate emergency response and operation and maintenance scheduling.

[0133] If the pressure value exceeds 45kg, it can be concluded that the battery pack has suffered a serious collision, which may cause damage to the battery. Therefore, it is necessary to shut down the battery charging and discharging output and report the battery location data. The battery pack backend service personnel will arrange for on-site inspection of the battery pack to determine if there are any safety issues based on the alarm information.

[0134] This application arranges 5 pressure sensors around and at the bottom of the battery pack to form a spatially distributed detection network. In the actual judgment process, as long as the pressure value P measured by any sensor meets the dynamic pressure threshold and rate criterion (i.e., P>μ+3σ, and dP / dt>set change rate), and P falls within the first set pressure range / second set pressure range / third set pressure range, it will be judged as a mild collision / moderate collision / severe collision. The advantage of this design is that it can capture local impacts on any part of the battery pack in a timely manner, avoiding safety hazards caused by single-point missed detection.

[0135] Assume that a sensor detects a pressure value P that satisfies P>μ+3σ, dP / dt>the set change rate, and P is within the first set pressure range. The system will trigger local recording of a mild collision and a buzzer warning response.

[0136] In this application, the pressure value of each sensor channel is compared with the dynamic pressure threshold in real time. When the pressure value exceeds the pressure threshold for the first time, the trigger time is recorded; if the pressure value continues to exceed the pressure threshold for more than the set time (the first set time, such as 20ms), it is determined to be a valid collision. Then, according to the size of the pressure peak, different response functions are called: recording the collision event (including time, pressure, sensor number, classification result), triggering local early warning, power limiting, fuse protection and other measures, and interacting with the BMS main control and cloud communication module through the API interface to realize data reporting and remote alarm.

[0137] All valid collision events are stored in a loop history record area for easy subsequent query and accident tracing. Once the alarm is triggered, the system will select a local or cloud alarm method based on the classification results, and can also provide GPS positioning information.

[0138] This application implements 4G cloud collaboration, and the EC200U communication module achieves high-speed data transmission (5Mbps) and precise positioning (±5m).

[0139] Specific implementation cases are as follows:

[0140] (1) Scenario: Battery replacement for two-wheeled electric vehicles (60V50Ah).

[0141] (2) Deployment effect:

[0142] A local warning is triggered when a 30cm drop is detected (pressure 28kg);

[0143] A side impact (10kg) triggers a cloud alarm and limits power to 50%;

[0144] A 50cm drop (pressure 47kg) triggers the fuse protection, and the GPS location is synchronized to the operation and maintenance platform.

[0145] (3) The test data is shown in Table 1 below.

[0146] Table 1

[0147] Test scenario False alarm rate Response time Positioning error Normal riding vibration 0.3％ - - 50cm drop to concrete floor 0％ 8ms ±3cm Side impact (10kg) 0％ 9ms ±5cm

[0148] This application proposes solutions to overcome the defects of the existing technology, as shown in Table 2.

[0149] Table 2

[0150]

[0151]

[0152] The battery pack collision detection system of this application is a BMS collaborative protection system based on multi-sensor data fusion, which achieves:

[0153] (1) Accurate detection of physical collisions of battery packs (positioning accuracy ±5cm, impact energy error <10%);

[0154] (2) Low false alarm rate (<0.5%) for dynamic pressure threshold determination;

[0155] (3) A three-level response mechanism (early warning / power limit / fuse) linked to the cloud;

[0156] (4) Hardware integration solution compatible with existing BMS architecture.

[0157] The battery pack collision detection system of this application has the following advantages:

[0158] (1) High safety: The fuse response time is less than 10ms, far exceeding the industry standard (GB / T 31485 requires 20ms).

[0159] (2) High economic efficiency: Hardware reuse rate >70%, BMS transformation cost reduced by 50%.

[0160] (3) High scalability: supports CAN bus protocol expansion and is compatible with more than 90% of electric vehicle BMS architectures.

[0161] The battery pack collision detection system of this application improves collision detection accuracy through multi-sensor data fusion, reduces false alarm rate based on dynamic pressure thresholds, establishes a hierarchical response mechanism and cloud-based collaborative protection system, and achieves seamless integration with existing BMS (hardware reuse rate >70%).

[0162] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. Battery pack collision detection system, characterized by: include: A pressure detection module, comprising a plurality of pressure detection units disposed on the battery pack, the pressure detection units being used to collect pressure values; The collision judgment module is used to judge whether the pressure value collected by the pressure detection unit is greater than the pressure threshold and whether the rate of change of the pressure value is greater than the set rate of change; when it is judged that the pressure value collected by any pressure detection unit is greater than the pressure threshold and the rate of change of the pressure value is greater than the set rate of change, a collision is determined to have occurred.

2. The battery pack collision detection system according to claim 1, characterized in that: The plurality of pressure detection units are distributed around and on the bottom of the battery pack.

3. The battery pack collision detection system according to claim 1, wherein: The collision judgment module is also used to: when it is determined that the pressure value collected by any pressure detection unit is greater than the pressure threshold and the change rate of the pressure value is greater than the set change rate, start timing; if the pressure value is greater than the pressure threshold for more than a first set time, it is determined that a collision has occurred.

4. The battery pack collision detection system according to claim 1, wherein: The collision judgment module is further used to: calculate the average value and standard deviation of the pressure values ​​collected by each pressure detection unit every second set time period, and calculate a pressure threshold; the pressure threshold is the sum of the average value and three times the standard deviation.

5. The battery pack collision detection system according to claim 1, characterized in that: The collision judgment module is further configured to: after determining that a collision occurs, judge the collision level based on the pressure value.

6. The battery pack collision detection system according to claim 5, characterized in that: The method of determining the collision level based on the pressure value specifically includes: If the pressure value is within the first set pressure range, the collision level is determined to be a level one collision; If the pressure value is within the second set pressure range, the collision level is determined to be a level 2 collision; If the pressure value is within the third set pressure range, the collision level is determined to be a level three collision; Wherein, any value within the first set pressure range is smaller than any value within the second set pressure range; and any value within the second set pressure range is smaller than any value within the third set pressure range.

7. The battery pack collision detection system according to claim 6, characterized in that: The collision judgment module is further used to: When the collision level is determined to be a level one collision, a local warning is issued and collision information is recorded locally. The collision information includes the collision time, pressure value, pressure detection unit number, and collision level; When the collision level is determined to be a level 2 collision, the battery pack is controlled to operate at limited power and an alarm message is sent to the cloud platform; When the collision level is determined to be a level three collision, the battery pack is fused for protection and the location information of the battery pack is sent to the cloud platform.

8. The battery pack collision detection system according to any one of claims 1 to 7, characterized in that: The collision judgment module is further used to: Before determining whether the pressure value collected by the pressure detection unit is greater than the pressure threshold, the pressure value collected by the pressure detection unit is filtered.

9. The battery pack collision detection system according to any one of claims 1 to 7, characterized in that: The collision judgment module is further used to: Before determining whether the pressure value collected by the pressure detection unit is greater than the pressure threshold, the pressure value collected by the pressure detection unit is filtered and temperature compensated.

10. The battery pack collision detection system according to claim 9, characterized in that: The temperature compensation formula is: P_real = P_measured + k*(T-T0); in, P_real is the pressure value after compensation; P_measured is the pressure value collected by the pressure detection unit; T is the current temperature; T0 is the calibration reference temperature; k is the temperature compensation coefficient.

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