Power battery pack safety prevention and control system for electric vehicle and control method

Abstract

Disclosed are a power battery pack safety prevention and control system for an electric vehicle and a control method. The power battery pack safety prevention and control system includes a signal collection device, a master controller, and a stepwise prevention and control actuator. The master controller includes a fault diagnosis device, a cell thermal runway determination device, and a battery pack thermal runway spread determination device which are respectively electrically connected to the stepwise prevention and control actuator and send different control instructions to the stepwise prevention and control actuator. The stepwise prevention and control actuator can perform different levels of prevention and control actions according to different control instructions sent by the fault diagnosis device, the cell thermal runway determination device, and the battery pack thermal runway spread determination device. The power battery pack safety prevention and control system for an electric vehicle can provide an active prevention and control measure and a passive prevention and control measure, accurately activate a prevention and control mechanism according to an actual situation of an accident in combination with the prevention and control capability of the prevention and control system, maximize the effect of the safety protection, and ensure the safety of the passenger in the electric vehicle.

What is claimed is: 
     
         1 . A power battery pack safety prevention and control system for an electric vehicle, comprising a battery pack for powering the electric vehicle, a signal collection device, a master controller, and a stepwise prevention and control actuator;
 wherein one end of the signal collection device is electrically connected to the battery pack, and another end of the signal collection device is electrically connected to the master controller, the signal collection device is configured to acquire monitoring information of the battery pack and transmit the monitoring information to the master controller;   the master controller comprises a fault diagnosis device, a cell thermal runaway determination device and a battery pack thermal runaway spread determination device; the fault diagnosis device, the cell thermal runaway determination device and the battery pack thermal runaway spread determination device are electrically connected to the stepwise prevention and control actuator respectively, and are respectively configured to send a control instruction to the stepwise prevention and control actuator;   the stepwise prevention and control actuator is configured to perform a prevention and control action according to control instructions sent by the fault diagnosis device, the cell thermal runaway determination device, and the battery pack thermal runaway spread determination device.   
     
     
         2 . The power battery pack safety prevention and control system for an electric vehicle according to  claim 1 , wherein the fault diagnosis device comprises an internal short-circuit detector, an external short-circuit detector, a charge-discharge fault detector, an insulation failure detector, a collision detector, a liquid leakage and fire detector, and an overheat detector;
 the internal short-circuit detector, the external short-circuit detector, the charge-discharge fault detector, the insulation failure detector, the collision detector, the liquid leakage and fire detector and the overheat detector are electrically connected to the signal collection device respectively;   the internal short-circuit detector, the external short-circuit detector, the charge-discharge fault detector, the insulation failure detector, the collision detector, the liquid leakage and fire detector and the overheat detector are respectively configured to perform a parallel fault diagnosis on different types of faults, determine a fault type and send a control instruction for a fault of a fault level one to the stepwise prevention and control actuator according to different fault types.   
     
     
         3 . The power battery pack safety prevention and control system for an electric vehicle according to  claim 2 , wherein the internal short-circuit detector comprises a processor, a selector, an electrochemical status determination device, a thermogenesis status determination device and a logic-arithmetic unit;
 one end of the electrochemical status determination device and one end of the thermogenesis status determination device are respectively connected to the battery pack;   the other end of the electrochemical status determination device and the other end of the thermogenesis status determination device are respectively connected to the processor;   the electrochemical status determination device is configured to acquire information of the battery pack having an extreme electrochemical status, perform a model-based electrochemical abnormal status detection, and output a detection result of an electrochemical status of the battery pack;   the thermogenesis status determination device is configured to acquire information of the battery pack having an extreme thermogenesis status, perform a model-based thermogenesis abnormal status detection, and output a detection result of a thermogenesis status of the battery pack;   the processor is configured to store position and status information of the battery pack, the processor is further configured to generate a control instruction of a prevention and control action;   the selector is configured to screen an extreme battery pack based on an average+difference model;   the logic-arithmetic unit is configured to perform a logical operation according to a detection results obtained by the electrochemical status determination device and the thermogenesis status determination device, and output an operation result to the processor.   
     
     
         4 . The power battery pack safety prevention and control system for an electric vehicle according to  claim 1 , wherein the cell thermal runaway determination device comprises a battery cell thermal runaway predictor and a battery cell thermal runaway locator respectively electrically connected to the signal collection device;
 the battery cell thermal runaway predictor is configured to predict a possibility of an occurrence of battery cell thermal runaway, the battery cell thermal runaway locator is configured to determine a zone in which the battery cell thermal runaway occurs;   the battery cell thermal runaway predictor and the battery cell thermal runaway locator are respectively configured to send a control instruction for a fault of a fault level two to the stepwise prevention and control actuator according to different possibilities of the occurrence of the battery cell thermal runaway and different zones in which the battery cell thermal runaway occurs.   
     
     
         5 . The power battery pack safety prevention and control system for an electric vehicle according to  claim 1 , wherein the battery pack thermal runaway spread determination device comprises a battery pack thermal runaway spread predictor and a battery pack thermal runaway spread locator respectively electrically connected to the signal collection device;
 the battery pack thermal runaway spread predictor is configured to determine whether thermal runaway spread occurs in the battery pack and an adjacent zone, the battery pack thermal runaway spread locator is configured to locate a zone in which the battery pack thermal runaway spread occurs;   the battery pack thermal runaway spread predictor and the battery pack thermal runaway spread locator are respectively configured to send a control instruction for a fault of a fault level three to the stepwise prevention and control actuator according to different conditions comprising whether the thermal runaway spread occurs in the battery pack, the zone in which the battery pack thermal runaway spread occurs, whether a thermal runaway spread-induced fire occurs in the battery pack, and whether a battery cell catches fire.   
     
     
         6 . The power battery pack safety prevention and control system for an electric vehicle according to  claim 1 , wherein the battery pack thermal runaway spread determination device further comprises a battery pack thermal runaway spread-induced fire determination device, a battery pack thermal runaway spread-induced explosion determination device and a timer;
 the battery pack thermal runaway spread-induced fire determination device, the battery pack thermal runaway spread-induced explosion determination device and the timer are electrically connected to the signal collection device respectively;   the battery pack thermal runaway spread-induced fire determination device is configured to determine whether a thermal runaway spread-induced fire occurs in the battery pack;   the battery pack thermal runaway spread-induced explosion determination device is configured to determine whether a thermal runaway spread-induced explosion occurs in the battery pack, and send a control instruction for a fault of a fault level four to the stepwise prevention and control actuator if an explosion occurs;   the timer is electrically connected to the battery pack thermal runaway spread-induced explosion determination device, and is configured to record a time interval from the battery cell thermal runaway to the explosion of the battery pack.   
     
     
         7 . The power battery pack safety prevention and control system for an electric vehicle according to  claim 1 , wherein the stepwise prevention and control actuator comprises an alarm device, a thermal runaway inducement suppression device, a thermal runaway zone suppression device, a fire extinguishing device and a safety relief device respectively electrically connected to the master controller;
 the thermal runaway inducement suppression device comprises a shutoff device and an isolating device; the shutoff device and the isolating device are respectively provided to perform a corresponding prevention and control action, the shutoff device is configured to shut off a fault cell and a fault zone circuit, the isolating device is configured to isolate the fault cell, isolate a charge-discharge circuit, and shut off a main circuit of the battery pack.   
     
     
         8 . The power battery pack safety prevention and control system for an electric vehicle according to  claim 7 , wherein the thermal runaway spread suppression system comprises a heat flow passive guide device and a heat flow active guide device, a heat exchanger and a combustible gas extraction device;
 the heat flow passive guide device is provided in a different zone of the battery pack and is configured to passively guide flow of heat when thermal runaway occurs;   the heat flow active guide device is provided in a different zone of the battery pack and is configured to actively guiding flow of heat when thermal runaway occurs;   the heat exchanger is provided in a different zone of the battery pack and is configured to complete heat exchange between the battery pack and an outside world;   the combustible gas extraction device is provided in a different zone of the battery pack and is configured to complete outward discharge of a combustible gas.   
     
     
         9 . The power battery pack safety prevention and control system for an electric vehicle according to  claim 8 , wherein the fire extinguishing device comprises a fire extinguishing agent tank body, a fire extinguishing agent delivery pipeline and a fire extinguishing agent injection valve body;
 the fire extinguishing agent tank body is connected to the fire extinguishing agent injection valve body through the fire extinguishing agent delivery pipeline;   the fire extinguishing agent injection valve body comprises a fire extinguishing agent injection valve body in a first zone I and a fire extinguishing agent injection valve body in a second zone II, the fire extinguishing agent injection valve body in the first zone I and the fire extinguishing agent injection valve body in the second zone II are configured to complete spraying of different doses of extinguishing agent.   
     
     
         10 . The power battery pack safety prevention and control system for an electric vehicle according to  claim 1 , wherein the master controller is in communication with the stepwise prevention and control actuator through a network. 
     
     
         11 . A control method for a power battery pack safety prevention and control system for an electric vehicle, wherein the power battery pack safety prevention and control system comprises:
 a battery pack for powering an electric vehicle;   a signal collection device, one end of which is electrically connected to the battery pack;   a master controller, electrically connected to the other end of the signal collection device; and   a stepwise prevention and control actuator, electrically connected to the master controller;   the control method comprises following steps:   S 100 : acquiring, by the signal collection device, monitoring information of the battery pack, and transmitting the monitoring information to the master controller;   S 200 : generating, by the master controller, a control instruction according to the monitoring information, and sending the control instruction to the stepwise prevention and control actuator;   S 300 : performing, by the stepwise prevention and control actuator, a prevention and control action according to the control instruction sent by the master controller.   
     
     
         12 . The control method for the power battery pack safety prevention and control system for the electric vehicle according to  claim 11 , wherein the master controller comprises a fault diagnosis device, a cell thermal runaway determination device and a battery pack thermal runaway spread determination device, the fault diagnosis device, the cell thermal runaway determination device and the battery pack thermal runaway spread determination device are respectively electrically connected to the stepwise prevention and control actuator;
 the step S 200  further comprises:   S 210 : generating, by one or more of the fault diagnosis device, the cell thermal runaway determination device and the battery pack thermal runaway spread determination device, at least one control instruction according to the monitoring information, and sending the at least one control instruction to the stepwise prevention and control actuator.   
     
     
         13 . The control method for the power battery pack safety prevention and control system for the electric vehicle according to  claim 12 , wherein the fault diagnosis device comprises an internal short-circuit detector, an external short-circuit detector, a charge-discharge fault detector, an insulation failure detector, a collision detector, a liquid leakage and fire detector and an overheat detector;
 the internal short-circuit detector, the external short-circuit detector, the charge-discharge fault detector, the insulation failure detector, the collision detector, the liquid leakage and fire detector and the overheat detector are respectively electrically connected to the signal collection device;   the step S 210  further comprises:   S 211 : respectively performing, by the internal short-circuit detector, the external short-circuit detector, the charge-discharge fault detector, the insulation failure detector, the collision detector, the liquid leakage and fire detector and the overheat detector, a parallel fault diagnosis on different types of faults, determining a fault type, and respectively sending a control instruction for a fault of a fault level one to the stepwise prevention and control actuator according to different fault types.   
     
     
         14 . The control method for the power battery pack safety prevention and control system for the electric vehicle according to  claim 12 , wherein the internal short-circuit detector comprises a processor, a selector, an electrochemical status determination device, a thermogenesis status determination device and a logic-arithmetic unit;
 one end of the electrochemical status determination device and one end of the thermogenesis status determination device are respectively connected to the battery pack, the other end of the electrochemical status determination device and the other end of the thermogenesis status determination device are respectively connected to the processor;   the control method further comprises:   acquiring, by the electrochemical status determination device, information of the battery pack having an extreme electrochemical status, performing a model-based electrochemical abnormal status detection, and outputting a detection result of an electrochemical status of the battery pack;   acquiring, by the thermogenesis status determination device, information of the battery pack having an extreme thermogenesis status, performing a model-based thermogenesis abnormal status detection, and outputting a detection result of a thermogenesis status of the battery pack;   storing, by the processor, location and status information of the battery pack, and generating a control instruction of a prevention and control action;   screening, by the selector, an extreme battery pack based on an “average+difference” model;   performing, by the logic-arithmetic unit, a logical operation according to detection results obtained by the electrochemical status determination device and the thermogenesis status determination device, and outputting an operation result to the processor.   
     
     
         15 . The control method for the power battery pack safety prevention and control system for the electric vehicle according to  claim 12 , wherein the cell thermal runaway determination device comprises a battery cell thermal runaway predictor and a battery cell thermal runaway locator respectively electrically connected to the signal collection device;
 the step S 210  further comprises:   S 212 : predicting, by the battery cell thermal runaway predictor, a possibility of an occurrence of battery cell thermal runaway; determining, by the battery cell thermal runaway locator, a zone in which the battery cell thermal runaway occurs;   S 213 : sending, by the battery cell thermal runaway predictor and the battery cell thermal runaway locator respectively, a control instruction for a fault of a fault level two to the stepwise prevention and control actuator according to different possibilities of occurrences of the battery cell thermal runaway and different zones in which the battery cell thermal runaway occurs.   
     
     
         16 . The control method for the power battery pack safety prevention and control system for the electric vehicle according to  claim 12 , wherein the battery pack thermal runaway spread determination device comprises a battery pack thermal runaway spread predictor and a battery pack thermal runaway spread locator respectively electrically connected to the signal collection device;
 the step S 210  further comprises:   S 214 : determining, by the battery pack thermal runaway spread predictor, whether thermal runaway spread occurs in the battery pack and an adjacent zone; locating, by the battery pack thermal runaway spread locator, a zone in which the battery pack thermal runaway spread occurs;   S 215 : sending, by the battery pack thermal runaway spread predictor and the battery pack thermal runaway spread locator respectively, a control instruction for a fault of a fault level three to the stepwise prevention and control actuator according to different conditions comprising whether thermal runaway spread occurs in the battery pack, a zone in which the battery pack thermal runaway spread occurs, whether a thermal runaway spread-induced fire occurs in the battery pack, and whether a battery cell catches fire.   
     
     
         17 . The control method for the power battery pack safety prevention and control system for the electric vehicle according to  claim 12 , wherein the battery pack thermal runaway spread determination device further comprises a battery pack thermal runaway spread-induced fire determination device, a battery pack thermal runaway spread-induced explosion determination device and a timer;
 the battery pack thermal runaway spread-induced fire determination device, the battery pack thermal runaway spread-induced explosion determination device, and the timer are electrically connected to the signal collection device respectively, and the timer is electrically connected to the battery pack thermal runaway spread-induced explosion determination device;   the step S 210  further comprises:   S 216 : determining, by the battery pack thermal runaway spread-induced fire determination device, whether a thermal runaway spread-induced fire occurs in the battery pack;   S 217 : determining, by the battery pack thermal runaway spread-induced explosion determiner, whether a thermal runaway spread-induced explosion occurs in the battery pack, and sending a control instruction for a fault of a fault level four to the stepwise prevention and control actuator if an explosion occurs;   S 218 : recording, by the timer, a time interval from the battery cell thermal runaway to the explosion of the battery pack.   
     
     
         18 . The control method for the power battery pack safety prevention and control system for the electric vehicle according to  claim 11 , wherein the stepwise prevention and control actuator comprises an alarm device, a thermal runaway inducement suppression device, a thermal runaway zone suppression device, a fire extinguishing device and a safety relief device respectively electrically connected to the master controller;
 the thermal runaway inducement suppression device comprises a shutoff device and an isolating device, the shutoff device and the isolating device are respectively provided to perform a corresponding prevention and control action;   the thermal runaway spread suppression system comprises a heat flow passive guide device, a heat flow active guide device, a heat exchanger, and a combustible gas extraction device; the heat flow passive guide device is provided in a different zone of the battery pack, the heat flow active guide device is provided in a different zone of the battery pack, the heat exchanger is provided in a different zone of the battery pack, the combustible gas extraction device is provided in a different zone of the battery pack;   the control method further comprises one or more of following steps:   shutting off, by the shutoff device, a fault cell and a fault zone circuit;   isolating, by the isolating device, the fault cell and a charge-discharge circuit, and shutting off a main circuit of the battery pack;   passively guiding, by the heat flow passive guide device, flow of heat;   actively guiding, by the heat flow active guide device, flow of heat;   implementing, by the heat exchanger, heat exchange between the battery pack and an outside world;   implementing, by the combustible gas extraction device, outward discharge of a combustible gas.   
     
     
         19 . The control method for the power battery pack safety prevention and control system for the electric vehicle according to  claim 18 , wherein the fire extinguishing device comprises a fire extinguishing agent tank body, a fire extinguishing agent delivery pipeline, and a fire extinguishing agent injection valve body; the fire extinguishing agent tank body is connected to the fire extinguishing agent injection valve body through the fire extinguishing agent delivery pipeline; the fire extinguishing agent injection valve body comprises a fire extinguishing agent injection valve body in a first zone I and a fire extinguishing agent injection valve body in a second zone II;
 the control method further comprises:   spraying, by the fire extinguishing agent injection valve body in the first zone I and the fire extinguishing agent injection valve body in the second zone II, different doses of fire extinguishing agent.   
     
     
         20 . A power battery pack safety prevention and control system for an electric vehicle, comprising a battery pack, a signal collection device, a master controller, and a stepwise prevention and control actuator;
 wherein the battery pack is configured to power the electric vehicle;   one end of the signal collection device is electrically connected to the battery pack, and the other end of the signal collection device is connected to the master controller, the signal collection device is configured to acquire monitoring information of the battery pack and transmit the monitoring information to the master controller;   the master controller comprises a fault diagnosis device, a cell thermal runaway determination device, and a battery pack thermal runaway spread determination device; the fault diagnosis device, the cell thermal runaway determination device and the battery pack thermal runaway spread determination device are electrically connected to the stepwise prevention and control actuator respectively, and are respectively configured to send a control instruction to the stepwise prevention and control actuator;   the stepwise prevention and control actuator is configured to perform a prevention and control action according to control instructions sent by the fault diagnosis device, the cell thermal runaway determination device and the battery pack thermal runaway spread determination device;   wherein the fault diagnosis device comprises an internal short-circuit detector, an external short-circuit detector, a charge-discharge fault detector, an insulation failure detector, a collision detector, a liquid leakage and fire detector and an overheat detector;   the internal short-circuit detector, the external short-circuit detector, the charge-discharge fault detector, the insulation failure detector, the collision detector, the liquid leakage and fire detector and the overheat detector are respectively electrically connected to the signal collection device;   the internal short-circuit detector, the external short-circuit detector, the charge-discharge fault detector, the insulation failure detector, the collision detector, the liquid leakage and fire detector and the overheat detector are respectively configured to perform a parallel fault diagnosis on different types of faults, determine a fault type, and send a control instruction for a fault of a fault level one to the stepwise prevention and control actuator according to different fault types;   wherein, the battery pack thermal runaway spread determination device further comprises a battery pack thermal runaway spread-induced fire determination, a battery pack thermal runaway spread-induced explosion determination device, and a timer;   the battery pack thermal runaway spread-induced fire determination device, the battery pack thermal runaway spread-induced explosion determination device and the timer are respectively electrically connected to the signal collection device;   the battery pack thermal runaway spread-induced fire determination device is configured to determine whether a thermal runaway spread-induced fire occurs in the battery pack;   the battery pack thermal runaway spread-induced explosion determination device is configured to determine whether a thermal runaway spread-induced explosion occurs in the battery pack, and send a control instruction for a fault of a fault level four to the stepwise prevention and control actuator if an explosion occurs;   the timer is electrically connected to the battery pack thermal runaway spread-induced explosion determination device, and is configured to record a time interval from battery cell thermal runaway to the explosion of the battery pack;   wherein, the stepwise prevention and control actuator comprises an alarm device, a thermal runaway inducement suppression device, a thermal runaway zone suppression device, a fire extinguishing device and a safety relief device respectively electrically connected to the master controller;   the thermal runaway inducement suppression device comprises a shutoff device and an isolating device; the shutoff device and the isolating device are respectively provided to perform a corresponding prevention and control action, the shutoff device is configured to shut off a fault cell and a fault zone circuit, and the isolating device is configured to isolate the fault cell, isolate a charge-discharge circuit, and shut off a main circuit of the battery pack.