Abstract: Presented are feedback control systems for monitoring battery system hardware, methods for making/operating such systems, and vehicles with wireless battery management systems (WBMS) governed through distributed feedback control. A method of operating a WBMS includes a wireless-enabled manager device selecting a batch of cell module assemblies (CMA) within the WBMS to communicate with to thereby retrieve data for their respective battery modules. A manager access control list (ACL) is created with respective media access control (MAC) addresses and ID data for the selected CMAs. A wireless connection is established between the manager device and a respective cell monitoring unit (CMU) for each selected CMA based on the corresponding MAC addresses and ID data in the manager ACL. The manager device downloads, from the CMU of each selected CMA, device data for each battery modules associated with the selected CMA. The manager device then switches the operating mode for each CMU.

Abstract: Presented are feedback control systems for monitoring battery system hardware, methods for making/operating such systems, and vehicles with wireless battery management systems (WBMS) governed through distributed feedback control. A method of operating a WBMS includes a wireless-enabled manager device selecting a batch of cell module assemblies (CMA) within the WBMS to communicate with to thereby retrieve data for their respective battery modules. A manager access control list (ACL) is created with respective media access control (MAC) addresses and ID data for the selected CMAs. A wireless connection is established between the manager device and a respective cell monitoring unit (CMU) for each selected CMA based on the corresponding MAC addresses and ID data in the manager ACL. The manager device downloads, from the CMU of each selected CMA, device data for each battery modules associated with the selected CMA. The manager device then switches the operating mode for each CMU.

Abstract: A system for evaluating battery connection quality in one or more battery modules of a battery assembly includes a battery testing unit having a housing including an upper surface and a lower surface. A plurality of testing modules are disposed on the lower surface of the housing to communicate with and electrically contact the one or more battery modules of the battery assembly. The plurality of testing modules each include at least one connector extending from a lower surface of the testing module and at least one contact disposed on one or more side surfaces of the testing module. A controller is in electrical communication with the at least one connector and at least one contacts to simultaneously evaluate voltage and resistance measurements of the one or more battery modules of the battery assembly.

Abstract: A method and a test fixture for evaluating a weld seam joining an electrode foil element and a terminal of a battery cell include segmenting the weld seam joining the electrode foil element and the terminal into a plurality of zones. For each of the zones, an electrical current is applied between the terminal and the electrode foil element in the zone, and a resistance is determined across the terminal and the electrode foil element in the zone. Integrity of the weld seam is evaluated for each of the zones based upon the resistance between the terminal and the electrode foil element in the zone.

Abstract: A method and a test fixture for evaluating a weld seam joining an electrode foil element and a terminal of a battery cell include segmenting the weld seam joining the electrode foil element and the terminal into a plurality of zones. For each of the zones, an electrical current is applied between the terminal and the electrode foil element in the zone, and a resistance is determined across the terminal and the electrode foil element in the zone. Integrity of the weld seam is evaluated for each of the zones based upon the resistance between the terminal and the electrode foil element in the zone.

Abstract: A system for evaluating battery connection quality in one or more battery modules of a battery assembly includes a battery testing unit having a housing including an upper surface and a lower surface. A plurality of testing modules are disposed on the lower surface of the housing to communicate with and electrically contact the one or more battery modules of the battery assembly. The plurality of testing modules each include at least one connector extending from a lower surface of the testing module and at least one contact disposed on one or more side surfaces of the testing module. A controller is in electrical communication with the at least one connector and at least one contacts to simultaneously evaluate voltage and resistance measurements of the one or more battery modules of the battery assembly.

Abstract: Systems and methods for determining the quality of battery cell tab electrical connections are presented. In certain embodiments, a first electrical current may be supplied between a first tab group and a second tab group of a battery cell group. A first voltage drop may be measured between the first tab group and the second tab group and a measured cell group resistance may be determined based on the measured first voltage drop. The measured cell group resistance may be compared with a reference cell group resistance to determine a quality of an associated battery cell tab electrical connection.

Abstract: A portable cell balancing repair tool for correcting cell-to-cell voltage imbalances. The tool defines a voltage set-point that identifies a desired voltage that the cells will be charged to for the cell-to-cell voltage balancing. The tool selects a cell to be balanced, measures the voltage of the selected cell and determines if the measured voltage is less than the voltage set-point. The tool charges the selected cell with a charging current for a predetermined period of time, and then determines if the voltage of the selected cell is greater than the voltage set-point after the time expires. The tool continues charging the selected cell at the charging current if the measured voltage is not greater than the voltage set-point, and determines if the charging current was at the minimum charging current if the measured voltage of the selected cell is greater than the voltage set-point.

Abstract: A method of evaluating battery packs is described. The method includes measuring a cell open voltage for each battery cell group in a section of battery cells; measuring a voltage under charge, or a voltage under load, or both, at a predetermined time interval for each battery cell group in the section of battery cells; determining the magnitude of the difference between the open cell voltage and the voltage under charge, or the voltage under load, or both, for each battery cell group in the section of battery cells by subtracting the voltage under charge from the cell open voltage, or subtracting the voltage under load from the cell open voltage, or both; and determining if the magnitude of the difference between the open cell voltage and the voltage under charge, or the voltage under load, or both, for each battery cell group in the section of battery cells exceeds a predetermined level.

Abstract: A portable cell balancing repair tool for correcting cell-to-cell voltage imbalances. The tool defines a voltage set-point that identifies a desired voltage that the cells will be charged to for the cell-to-cell voltage balancing. The tool selects a cell to be balanced, measures the voltage of the selected cell and determines if the measured voltage is less than the voltage set-point. The tool charges the selected cell with a charging current for a predetermined period of time, and then determines if the voltage of the selected cell is greater than the voltage set-point after the time expires. The tool continues charging the selected cell at the charging current if the measured voltage is not greater than the voltage set-point, and determines if the charging current was at the minimum charging current if the measured voltage of the selected cell is greater than the voltage set-point.

Abstract: A method of evaluating battery packs is described. The method includes measuring a cell open voltage for each battery cell group in a section of battery cells; measuring a voltage under charge, or a voltage under load, or both, at a predetermined time interval for each battery cell group in the section of battery cells; determining the magnitude of the difference between the open cell voltage and the voltage under charge, or the voltage under load, or both, for each battery cell group in the section of battery cells by subtracting the voltage under charge from the cell open voltage, or subtracting the voltage under load from the cell open voltage, or both; and determining if the magnitude of the difference between the open cell voltage and the voltage under charge, or the voltage under load, or both, for each battery cell group in the section of battery cells exceeds a predetermined level.

Abstract: A method of operating a combustor to heat a fuel processor in a fuel cell system, in which the fuel processor generates a hydrogen-rich stream a portion of which is consumed in a fuel cell stack and a portion of which is discharged from the fuel cell stack and supplied to the combustor, and wherein first and second streams are supplied to the combustor, the first stream being a hydrocarbon fuel stream and the second stream consisting of said hydrogen-rich stream, the method comprising the steps of monitoring the temperature of the fuel processor; regulating the quantity of the first stream to the combustor according to the temperature of the fuel processor; and comparing said quantity of said first stream to a predetermined value or range of predetermined values.

Abstract: A method and apparatus for controlling the temperature of a combustor in a fuel cell apparatus includes a fast acting air bypass valve connected in parallel with an air inlet to the combustor. A predetermined excess quantity of air is supplied from an air source to a series connected fuel cell and combustor. The predetermined excess quantity of air is provided in a sufficient amount to control the temperature of the combustor during start-up of the fuel processor when the load on the fuel cell is zero and to accommodate any temperature transients during operation of the fuel cell.

Abstract: In an improved method, the voltage of one or more cells in a fuel cell stack is monitored. The monitored voltage is compared to first and second preselected voltage values as a function of load, where the second preselected value is less than the first preselected value. Next, either a first signal is generated if the monitored voltage is less than the first preselected voltage value and greater than or equal to the second preselected voltage value; or a second signal is generated if the monitored voltage is less than the second preselected voltage value.