Battery pack and connecting circuits of battery modules

Abstract

A battery pack and connecting circuits of battery modules. The battery pack includes a plurality battery modules connected in series, wherein each battery module is provided with a connecting circuit. When the battery module operates normally, the connecting circuit serially connects the current battery module to the previous battery module and the succeeding battery module. When the battery module operates abnormally, the connecting circuit selectively disconnects the battery module, and if it disconnects the current battery module, it directly connects the previous battery module and the succeeding battery module in series. When a battery module is damaged abnormal, the current damaged battery module can be disconnected from the series battery pack and bypassed. As such, the previous battery module may be directly connected with the succeeding battery module, ensuring the normal connection of the series circuit.

What is claimed is: 
     
         1 . A battery pack in a vehicle, the battery pack comprising:
 a plurality of battery modules connected through a connecting circuit, the plurality of battery modules including a first battery module; and   a control device configured to selectively disconnect any one of the plurality of battery modules from the connecting circuit, wherein:   the control device is configured to
 obtain a first value for a first parameter for the first battery module; 
 obtain a second value for a second parameter for the first battery module; 
 determine whether the first battery module is in a first state based on the first value and second value; 
 determine whether the first battery module is in a second state based on the first value and second value; and 
 when the first battery module is determined to be in the second state, generate instructions for removing the first battery module from the connecting circuits, and a warning message. 
   
     
     
         2 . The battery pack of  claim 1 , wherein:
 determine whether the first battery is in a third state based on the first value and second value; and   when the first battery module is determined to be in the third state, generate instructions for removing the first battery module from the connecting circuits, and a safety message.   
     
     
         3 . The battery pack of  claim 1 , wherein each battery module is provided with a positive terminal and a negative terminal, and each connecting circuit comprises:
 a first switch;   a second switch; and   a bridge, comprising a first end point and a second end point, which are electrically connected with each other; and, wherein   the first switch is caused to selectively connect or disconnect the negative terminal of a second battery module in the plurality of battery modules with or from the positive terminal of the first battery module, and correspondingly disconnect or connect the negative terminal of the second battery module from or with the first end point of the bridge; and   the second switch is caused to selectively connect or disconnect the positive terminal of a third battery module in the plurality of battery modules with or from the negative terminal of the first battery module, and correspondingly disconnect or connect the positive terminal of the third battery module from or with the second end point of the bridge.   
     
     
         4 . The battery pack of  claim 1 , wherein the first parameter measures a working voltage for each of the battery modules and the second parameter measures a working temperature for each of the battery modules. 
     
     
         5 . The battery pack of  claim 3 , further comprising,
 a driving circuit configured to control connection states of the first switch and the second switch according to control signals transmitted by the control device.   
     
     
         6 . The battery pack of  claim 5 , further comprising:
 monitoring circuits, which are respectively connected with the plurality of battery modules, and configured to monitor working states of the plurality of battery modules and transmit monitoring signals to the control device; and   a battery monitoring unit provided within the control device and configured to receive the monitoring signals of the monitoring circuits and analyze the monitoring signals,   wherein the control device controls the plurality of driving circuits according to a determination result of the battery monitoring system with respect to the working states of the battery modules.   
     
     
         7 . The battery pack of  claim 4 , wherein,
 when the working voltage V of the first battery module is less than a lower limit Vbot1 or the working temperature T is greater than an upper limit Ttop1, the battery monitoring unit determines that the first battery module is operating in the abnormal state, and transmits a signal indicating the abnormal state to a processor for analysis; and, wherein   the processor is configured to analyze a working voltage state and a working temperature state of the first battery module to determine whether to disconnect the first battery module operating in the abnormal state and transmit one or more fault signals to a vehicle control unit (VCU);   wherein, when the processor analyzes the working voltage state of the current battery module, the working voltage V of the current battery module is compared with a safety lower limit Vbot2, the first battery module is determined to be in a state A if Vbot1>V>Vbot2, and the first battery module is determined to be in a state B if V<Vbot2;   when the processor analyzes the working temperature state of the first battery module, the working temperature T of the battery module is compared with a safety upper limit Ttop2, the first battery module is determined to be in a state C if Ttop2>T>Ttop1, and the first battery module is determined to be in a state D if T>Ttop2;   when the processor determines that the first battery module is in the state A or C, the processor determines that the first battery module is operating in the abnormal state without an immediate danger, and determines not to disconnect the first battery module, maintains the connection of the first battery module, and transmits a fault signal of warning a driver to drive to a maintenance station as early as possible to the VCU;   when the processor determines that the first battery module is in the state B, B and C, A and C, A and D, or D, the processor determines that the current battery module is operating in the abnormal state with a potential danger, and disconnects the current battery module, and transmits a fault signal of warning the driver to drive to the maintenance station immediately to the VCU; and   when the processor determines that the first battery module is in the state B and D, the processor determines that the current battery module is operating in the abnormal state with an immediate danger, and disconnects the abnormal battery module, and transmits a fault signal of warning the driver to leave the vehicle immediately to the VCU.   
     
     
         8 . A method of controlling a vehicle battery pack having a plurality of battery modules connected through connecting circuits, the plurality of battery modules including a first battery module, each battery module connected to a connecting circuit, said method comprising:
 monitoring multiple working parameters of the battery modules, the working parameters including a first parameter and a second parameter;   receive a first value of the first parameter for the first battery module;   receive the second parameter for the first battery module from the battery monitoring unit;   determine whether the first battery module is in a first state based on the first value and second value;   determine whether the first battery module is in a second state based on the first value and second value;   when the first battery module is determined to be in the second state, generate instructions for removing the first battery module from the connecting circuits, and a warning message.   
     
     
         9 . The method of  claim 8 , wherein each battery module is provided with a positive terminal and a negative terminal, and each connecting circuit comprises:
 a first switch;   a second switch;   a bridge, comprising a first end point and a second end point, which are electrically connected with each other;   wherein said disconnecting includes: in the connecting circuit of the first battery module
 selectively disconnecting, by the first switch, a negative terminal of a second battery module in the plurality of battery modules from a positive terminal of the first battery module, and connecting, by the first switch, a negative terminal of the second battery module with the first end point of the bridge, and 
 selectively disconnecting, by the second switch, a positive terminal of a third battery module in the plurality of battery modules from the negative terminal of the first battery module, and connecting, by the second switch, a positive terminal of the third battery module with the second end point of the bridge. 
   
     
     
         10 . The method of  claim 8 , further comprising
 determining whether the first battery is in a third state based on the first value and second value; and   when the first battery module is determined to be in the third state, generate instructions for removing the first battery module from the connecting circuits, and a safety message.   
     
     
         11 . The method of  claim 10 , further comprising controlling, by a driving circuit of the plurality of driving circuits, connection states of the first switch and the second switch according to the control signals transmitted by the control device. 
     
     
         12 . The method of  claim 11 , further comprising:
 monitoring working states of the plurality of battery modules via monitoring circuits respectively connected with the plurality of battery modules;   transmitting monitoring signals from the monitoring circuits to the control device;   receiving the monitoring signals at a battery monitoring unit provided within the control device;   analyzing the monitoring signals via the battery monitoring unit; and   controlling the plurality of driving circuits via the control device according to a determination result of the battery monitoring unit with respect to the working states of the battery modules.   
     
     
         13 . The method of  claim 12 , wherein,
 the first parameter includes a working voltage V and the second parameter includes a working temperature T of the plurality of battery modules, and wherein   when the working voltage V of the first battery module is less than a lower limit Vbot1 or the working temperature T is greater than an upper limit Ttop1, the method comprises determining that the first battery module is operating in the abnormal state, and transmitting a signal indicating the abnormal state to a processor of the control device.   
     
     
         14 . The method of  claim 13 , further comprising:
 analyzing the working voltage state and the working temperature state of the first battery module to determine whether to disconnect the current battery module operating in the abnormal state and transmit one or more fault signals to a vehicle control unit (VCU);   wherein, analyzing the working voltage state of the first battery module comprises
 comparing the working voltage V of the first battery module with a safety lower limit Vbot2, and 
 determining the first battery module to be in a state A if Vbot1>V>Vbot2, and to be in a state B if V<Vbot2; and 
   analyzing the working temperature state of the first battery module comprises comparing the working temperature T of the battery module with a safety upper limit Ttop2,
 determining the first battery module to be in a state C if Ttop2>T>Ttop1, and 
 determining the first battery module to be in a state D if T>Ttop2.