Abstract: A battery system includes a first cell balancing circuit electrically coupled to first and second sense lines and to a first battery cell. The battery system includes an integrated circuit measuring a first cell voltage between first and second sense lines at a first time while a first cell balancing circuit is turned off, and a second cell voltage between second and third sense lines at the first time while the second cell balancing circuit is turned off, and determining first and second cell voltage values based on the first and second cell voltages, respectively. A microcontroller receives the first and second cell voltage values and determines that an open circuit condition exists in the first balancing circuit if the first cell voltage value is greater than a first threshold voltage value, or the second cell voltage value is less than a second threshold voltage value.

Abstract: A battery system has a first cell balancing circuit and a second cell balancing circuit with a bus bar disposed therebetween. The battery system further includes an integrated circuit measuring a first voltage between two sense lines coupled to opposite ends of the bus bar while the first cell balancing circuit and a second cell balancing circuit are turned off, and determining a voltage value based on the first voltage. A microcontroller receives the voltage value and determines that an open circuit condition exists in the bus bar if the voltage value is greater than a threshold voltage value.

Abstract: A battery system has first and second cell balancing circuits with a bus bar disposed therebetween. The battery system further includes an integrated circuit measuring a first voltage between two sense lines coupled to opposite ends of the bus bar while the first and second cell balancing circuits are turned off, and determining a voltage value based on the first voltage. The microcontroller receives the voltage value and determines that an open circuit condition exists in the bus bar if the voltage value is greater than a threshold voltage value.

Abstract: A battery system includes a first cell balancing circuit electrically coupled to first and second sense lines and to a first battery cell. The battery system includes an integrated circuit measuring a first cell voltage between first and second sense lines at a first time while a first cell balancing circuit is turned off, and a second cell voltage between second and third sense lines at the first time while the second cell balancing circuit is turned off, and determining first and second cell voltage values based on the first and second cell voltages, respectively. A microcontroller receives the first and second cell voltage values and determines that an open circuit condition exists in the first balancing circuit if the first cell voltage value is greater than a first threshold voltage value, or the second cell voltage value is less than a second threshold voltage value.

Abstract: A battery cell assembly includes a thin sensor assembly having a plastic sheet, first, second, third, and fourth conductive pads, first and second resistive traces, a sensing circuit, a microprocessor, and an electrical connector. The plastic sheet has a first side and a second side. The plastic sheet further having first and second sheet portions, a first connecting portion, and first, second, and third tabs. The first connecting portion is coupled to and between the first and second sheet portions. The first and second resistive traces are disposed directly on and coupled to the first and second sheet portions, respectively. The first and second conductive pads are disposed directly on and coupled to the first and second tabs, respectively, on the first side.

Abstract: A battery cell assembly having a battery cell and a thin profile sensor is provided. The assembly includes a battery cell having a housing and first and second electrical terminals extending from the housing. The assembly further includes a thin profile sensor having a microprocessor and a sensing circuit. The sensing circuit is coupled directly to the housing. The sensing circuit generates a signal that is indicative of an operational parameter value of the battery cell. The microprocessor is programmed to determine the operational parameter value based on the signal from the sensing circuit. The assembly further includes a protective layer coupled to the thin profile sensor such that the sensor is disposed between the protective layer and the housing.

Abstract: A battery cell assembly having a battery cell and a thin profile sensor is provided. The battery cell has a housing and first and second electrical terminals extending therefrom. The thin profile sensor has a flexible plastic sheet, a microprocessor, and a sensing circuit. The microprocessor and the sensing circuit are coupled to the flexible plastic sheet. The flexible plastic sheet is coupled to an exterior surface of the housing of the battery cell. The sensing circuit generates a signal that is indicative of an operational parameter value of the battery cell. The microprocessor determines the operational parameter value based on the signal from the sensing circuit.

Abstract: A battery cell assembly includes a thin sensor assembly having a plastic sheet, first, second, third, and fourth conductive pads, first and second resistive traces, a sensing circuit, a microprocessor, and an electrical connector. The plastic sheet has a first side and a second side. The plastic sheet further having first and second sheet portions, a first connecting portion, and first, second, and third tabs. The first connecting portion is coupled to and between the first and second sheet portions. The first and second resistive traces are disposed directly on and coupled to the first and second sheet portions, respectively. The first and second conductive pads are disposed directly on and coupled to the first and second tabs, respectively, on the first side.

Abstract: A battery cell assembly having a battery cell and a thin profile sensor is provided. The battery cell has a housing and first and second electrical terminals. The thin profile sensor has a flexible plastic sheet, and a microprocessor, a sensing circuit, and a heat generating circuit coupled to the flexible plastic sheet. The flexible plastic sheet is coupled to the battery cell. The microprocessor determines a first voltage value representing an open circuit voltage, and a second voltage value of the battery cell when the battery cell is supplying electrical current through the heat generating circuit. The microprocessor determines a current value when the battery cell is supplying the electrical current through the heat generating circuit, and determines an internal resistance value based on the first voltage value, the second voltage value, and the current value.

Abstract: A test system for a battery pack having at least first and second battery modules is provided. The system includes a high voltage service disconnect assembly having a housing and an electrically-actuated switch. The system further includes a microprocessor that generates a first signal to induce the switch to have a closed operational position to electrically couple the first battery module to the second battery module. The sensor generates a second signal associated with the battery pack. The microprocessor stops generating the first signal to induce the switch to have an open operational position to electrically decouple the first battery module from the second battery module when the first signal is greater than a threshold level.

Abstract: A pre-charging system for a capacitor in a voltage inverter for an electric motor is provided. The system includes a microprocessor that generates a first control signal, and a pre-charging circuit coupled to the microprocessor. The pre-charging circuit has a counter circuit, a voltage pulse generating circuit, and a drive circuit. The counter circuit generates a first plurality of voltage pulses, in response to the first control signal. The voltage pulse generating circuit generates each voltage pulse of a second plurality of voltage pulses at a respective time interval while an instantaneous current flowing through a pre-charging resistor is less than a threshold level. The drive circuit has a transistor that outputs a third plurality of voltage pulses in response to the second plurality of voltage pulses to increase a voltage across the capacitor.

Abstract: A system for determining isolation resistances of a battery pack includes a voltage source, a voltage meter, and a microprocessor. The voltage source is disposed external of the battery pack. The voltage source applies an output voltage on first and second electrical terminals. The voltage meter measures a first voltage level between the first electrical terminal and the housing, and a second voltage level between the first electrical terminal and the housing when a resistor is electrically coupled between the first electrical terminal and the housing. The voltage meter measures a third voltage level between the second electrical terminal and the housing, and a fourth voltage level between the second electrical terminal and the housing when the resistor is electrically coupled between the second electrical terminal and the housing. The microprocessor determines a first isolation resistance value based on the first, second, and third voltage levels.

Abstract: A battery cell assembly having a battery cell and a thin profile sensor is provided. The assembly includes a battery cell having a housing and first and second electrical terminals extending from the housing. The assembly further includes a thin profile sensor having a microprocessor and a sensing circuit. The sensing circuit is coupled directly to the housing. The sensing circuit generates a signal that is indicative of an operational parameter value of the battery cell. The microprocessor is programmed to determine the operational parameter value based on the signal from the sensing circuit. The assembly further includes a protective layer coupled to the thin profile sensor such that the sensor is disposed between the protective layer and the housing.

Abstract: A pre-charging system for a capacitor in a voltage inverter for an electric motor is provided. The system includes a microprocessor that generates a first control signal, and a pre-charging circuit coupled to the microprocessor. The pre-charging circuit has a counter circuit, a voltage pulse generating circuit, and a drive circuit. The counter circuit generates a first plurality of voltage pulses, in response to the first control signal. The voltage pulse generating circuit generates each voltage pulse of a second plurality of voltage pulses at a respective time interval while an instantaneous current flowing through a pre-charging resistor is less than a threshold level. The drive circuit has a transistor that outputs a third plurality of voltage pulses in response to the second plurality of voltage pulses to increase a voltage across the capacitor.

Abstract: A system for determining an isolation resistance is provided. The system includes a voltage source that applies an output voltage level between first and second electrical terminals of a battery pack. The system further includes a voltage meter that measures a first voltage level between the first electrical terminal and a vehicle chassis, and measures a second voltage level between the first electrical terminal and the vehicle chassis when a resistor is coupled between the first electrical terminal and the vehicle chassis. The voltage meter measures a third voltage level between the second electrical terminal and the vehicle chassis. The system further includes a microprocessor that determines a first isolation resistance value based on the first, second, third voltage levels and the predetermined resistance level.

Abstract: A battery cell assembly having a battery cell and a thin profile sensor is provided. The battery cell has a housing and first and second electrical terminals. The thin profile sensor has a flexible plastic sheet, and a microprocessor, a sensing circuit, and a heat generating circuit coupled to the flexible plastic sheet. The flexible plastic sheet is coupled to the battery cell. The microprocessor determines a first voltage value representing an open circuit voltage, and a second voltage value of the battery cell when the battery cell is supplying electrical current through the heat generating circuit. The microprocessor determines a current value when the battery cell is supplying the electrical current through the heat generating circuit, and determines an internal resistance value based on the first voltage value, the second voltage value, and the current value.

Abstract: A battery cell assembly having a battery cell and a thin profile sensor is provided. The battery cell has a housing and first and second electrical terminals extending therefrom. The thin profile sensor has a flexible plastic sheet, a microprocessor, and a sensing circuit. The microprocessor and the sensing circuit are coupled to the flexible plastic sheet. The flexible plastic sheet is coupled to an exterior surface of the housing of the battery cell. The sensing circuit generates a signal that is indicative of an operational parameter value of the battery cell. The microprocessor determines the operational parameter value based on the signal from the sensing circuit.

Abstract: A system for determining isolation resistances of a battery pack includes a voltage source, a voltage meter, and a microprocessor. The voltage source is disposed external of the battery pack. The voltage source applies an output voltage on first and second electrical terminals. The voltage meter measures a first voltage level between the first electrical terminal and the housing, and a second voltage level between the first electrical terminal and the housing when a resistor is electrically coupled between the first electrical terminal and the housing. The voltage meter measures a third voltage level between the second electrical terminal and the housing, and a fourth voltage level between the second electrical terminal and the housing when the resistor is electrically coupled between the second electrical terminal and the housing. The microprocessor determines a first isolation resistance value based on the first, second, and third voltage levels.

Abstract: A test system for a battery pack having at least first and second battery modules is provided. The system includes a high voltage service disconnect assembly having a housing and an electrically-actuated switch. The system further includes a microprocessor that generates a first signal to induce the switch to have a closed operational position to electrically couple the first battery module to the second battery module. The sensor generates a second signal associated with the battery pack. The microprocessor stops generating the first signal to induce the switch to have an open operational position to electrically decouple the first battery module from the second battery module when the first signal is greater than a threshold level.

Abstract: A system for determining an isolation resistance is provided. The system includes a voltage source that applies an output voltage level between first and second electrical terminals of a battery pack. The system further includes a voltage meter that measures a first voltage level between the first electrical terminal and a vehicle chassis, and measures a second voltage level between the first electrical terminal and the vehicle chassis when a resistor is coupled between the first electrical terminal and the vehicle chassis. The voltage meter measures a third voltage level between the second electrical terminal and the vehicle chassis. The system further includes a microprocessor that determines a first isolation resistance value based on the first, second, third voltage levels and the predetermined resistance level.