Abstract: For each cell in a plurality of cells from a same manufacturing run, a first and a second cell characteristic are received in order to obtain a plurality of cell characteristics. For each cell, a batch compatibility number that is associated with a number of compatible cells that that cell is compatible with is determined based at least in part on the plurality of cell characteristics. The plurality of cells is sorted according to the batch compatibility numbers to obtain a sorted list of cells. A plurality of compatible cells to include in a battery is selected from the plurality of cells, including by evaluating the plurality of cells according to the order of the sorted list of cells and beginning with the lowest batch compatibility number.

Abstract: A power distribution circuit for an electrically powered aircraft includes a plurality of batteries and a plurality of electric propulsion systems. A plurality of power distribution circuits each couple a battery of the plurality of batteries to two or more electric propulsion systems. The plurality of electric propulsion systems are positioned on the aircraft to apply balanced forces to the aircraft such that in the event of a failure, the aircraft remains stable and only experiences a loss in altitude or speed.

Abstract: One or more battery sub-modules are selected by obtaining at least one voltage from each battery sub-module and selecting based at least in part on the obtained voltages. The battery sub-modules are electrically connected in series in order to provide power to a primary load. Each battery sub-module includes a plurality of cells electrically connected in series and each battery sub-module further includes a battery management system that monitors the cells in that battery sub-module. Those battery management systems in the selected sub-modules are turned off so that the battery management systems in the selected sub-modules do not consume power at least temporarily from the cells in the selected sub-modules while (1) the battery sub-modules are not providing power to the primary load and (2) the battery sub-modules are not being charged.

Abstract: For each cell in a plurality of cells from a same manufacturing run, a first and a second cell characteristic are received in order to obtain a plurality of cell characteristics. For each cell, a batch compatibility number that is associated with a number of compatible cells that that cell is compatible with is determined based at least in part on the plurality of cell characteristics. The plurality of cells is sorted according to the batch compatibility numbers to obtain a sorted list of cells. A plurality of compatible cells to include in a battery is selected from the plurality of cells, including by evaluating the plurality of cells according to the order of the sorted list of cells and beginning with the lowest batch compatibility number.

Abstract: Various embodiments of a technique to estimate and monitor a self-discharge rate for use as a measure of battery health are described herein. In some embodiments, the technique includes a system including a processor and a memory coupled with the processor. The memory is configured to provide the processor with instructions that when executed cause the processor to receive a plurality of snapshots obtained by monitoring a battery system in a quiescent state at a plurality of times. Each snapshot includes a plurality of cell state values at one of the plurality of times. The memory is further configured to provide the processor with instructions that when executed cause the processor to estimate a self-discharge indicator using at least one snapshot in the plurality of snapshots, compare the self-discharge indicator to a threshold, and recommend a remedy for the battery system in response to the self-discharge indicator exceeding the threshold.

Abstract: A first portion of a series battery is arranged where the first portion of the series battery produces a first magnetic field and the series battery includes a plurality of charge storage devices, a negative output terminal, a positive output terminal, and a plurality of intradevice connections connecting the plurality of charge storage devices in series. A second portion of the series battery is arranged such that a second magnetic field produced by the second portion of the series battery at least partially cancels out the first magnetic field.

Abstract: A power delivery system includes a controller, configured to receive a voltage indication signal indicating a measured voltage of a battery management system and to determine whether first and second diodes of the battery management system are faulty based on the voltage indication signal. The controller is also configured to respectively receive first and second current indication signals from first and second current sensors of the battery management system and to determine whether the first and second diodes of the first battery management system are faulty based on the first and second current indication signals.

Abstract: A first portion of a series battery is arranged where the first portion of the series battery produces a first magnetic field and the series battery includes a plurality of charge storage devices, a negative output terminal, a positive output terminal, and a plurality of intradevice connections connecting the plurality of charge storage devices in series. A second portion of the series battery is arranged such that a second magnetic field produced by the second portion of the series battery at least partially cancels out the first magnetic field.

Abstract: Battery management systems and methods can provide real-time automated monitoring of various aspects of battery health and operation. Some battery management systems can use an equivalent cell circuit model to predict a range for the expected behavior of a battery cell under actual operating conditions in real-time. The prediction can be compared to the actual behavior of the cell to determine whether an anomaly exists. Some battery management systems can maintain an estimate of battery state-of-health parameters such as charge capacity and internal resistance and can update these estimates in real time while the battery is being discharged and/or charged. Anomalous variations in a monitored parameter can trigger a real-time fault notification.

Abstract: For each cell in a plurality of cells from a same manufacturing run, a first and a second cell characteristic are received in order to obtain a plurality of cell characteristics. For each cell, a batch compatibility number that is associated with a number of compatible cells that that cell is compatible with is determined based at least in part on the plurality of cell characteristics. The plurality of cells is sorted according to the batch compatibility numbers to obtain a sorted list of cells. A plurality of compatible cells to include in a battery is selected from the plurality of cells, including by evaluating the plurality of cells according to the order of the sorted list of cells and beginning with the lowest batch compatibility number.

Abstract: Battery management systems and methods can provide real-time automated monitoring of various aspects of battery health and operation. Some battery management systems can use an equivalent cell circuit model to predict a range for the expected behavior of a battery cell under actual operating conditions in real-time. The prediction can be compared to the actual behavior of the cell to determine whether an anomaly exists. Some battery management systems can maintain an estimate of battery state-of-health parameters such as charge capacity and internal resistance and can update these estimates in real time while the battery is being discharged and/or charged. Anomalous variations in a monitored parameter can trigger a real-time fault notification.

Abstract: For each cell in a plurality of cells from a same manufacturing run, a first and a second cell characteristic are received in order to obtain a plurality of cell characteristics. For each cell, a batch compatibility number that is associated with a number of compatible cells that that cell is compatible with is determined based at least in part on the plurality of cell characteristics. The plurality of cells is sorted according to the batch compatibility numbers to obtain a sorted list of cells. A plurality of compatible cells to include in a battery is selected from the plurality of cells, including by evaluating the plurality of cells according to the order of the sorted list of cells and beginning with the lowest batch compatibility number.

Abstract: A power distribution circuit for an electrically powered aircraft includes a plurality of batteries and a plurality of electric propulsion systems. A plurality of isolated power distribution circuits each couple a battery of the plurality of batteries to two or more electric propulsion systems. The plurality of electric propulsion systems are positioned on the aircraft to apply balanced forces to the aircraft such that in the event of a failure, the aircraft remains stable and only experiences a loss in altitude or speed.

Abstract: A power delivery system includes a controller, configured to receive a voltage indication signal indicating a measured voltage of a battery management system and to determine whether first and second diodes of the battery management system are faulty based on the voltage indication signal. The controller is also configured to respectively receive first and second current indication signals from first and second current sensors of the battery management system and to determine whether the first and second diodes of the first battery management system are faulty based on the first and second current indication signals.

Abstract: One or more battery sub-modules are selected by obtaining at least one voltage from each battery sub-module and selecting based at least in part on the obtained voltages. The battery sub-modules are electrically connected in series in order to provide power to a primary load. Each battery sub-module includes a plurality of cells electrically connected in series and each battery sub-module further includes a battery management system that monitors the cells in that battery sub-module. Those battery management systems in the selected sub-modules are turned off so that the battery management systems in the selected sub-modules do not consume power at least temporarily from the cells in the selected sub-modules while (1) the battery sub-modules are not providing power to the primary load and (2) the battery sub-modules are not being charged.

Abstract: Various embodiments of a technique to estimate and monitor a self-discharge rate for use as a measure of battery health are described herein. In some embodiments, the technique includes a system including a processor and a memory coupled with the processor. The memory is configured to provide the processor with instructions that when executed cause the processor to receive a plurality of snapshots obtained by monitoring a battery system in a quiescent state at a plurality of times. Each snapshot includes a plurality of cell state values at one of the plurality of times. The memory is further configured to provide the processor with instructions that when executed cause the processor to estimate a self-discharge indicator using at least one snapshot in the plurality of snapshots, compare the self-discharge indicator to a threshold, and recommend a remedy for the battery system in response to the self-discharge indicator exceeding the threshold.

Abstract: Embodiments provide battery cells and/or battery submodules including a phase change material (PCM) for absorbing excess heat that may be released within the battery cell and/or battery submodule. The PCM may be provided in form of a layer within the battery cell in addition to a thermal insulation layer. Alternatively, the PCM layer may replace the thermal insulation layer. The PCM may be provided on one or more sides of the battery submodule within a container that contains the battery submodule. The PCM may be a solid PCM provided in form of a layer and/or one or more strips. The PCM may also include a liquid PCM that is provided in the container containing the battery submodule.

Abstract: One or more battery sub-modules are selected by obtaining at least one voltage from each battery sub-module and selecting based at least in part on the obtained voltages. The battery sub-modules are electrically connected in series in order to provide power to a primary load. Each battery sub-module includes a plurality of cells electrically connected in series and each battery sub-module further includes a battery management system that monitors the cells in that battery sub-module. Those battery management systems in the selected sub-modules are turned off so that the battery management systems in the selected sub-modules do not consume power at least temporarily from the cells in the selected sub-modules while (1) the battery sub-modules are not providing power to the primary load and (2) the battery sub-modules are not being charged.

Abstract: Battery management systems and methods can provide real-time automated monitoring of various aspects of battery health and operation. Some battery management systems can use an equivalent cell circuit model to predict a range for the expected behavior of a battery cell under actual operating conditions in real-time. The prediction can be compared to the actual behavior of the cell to determine whether an anomaly exists. Some battery management systems can maintain an estimate of battery state-of-health parameters such as charge capacity and internal resistance and can update these estimates in real time while the battery is being discharged and/or charged. Anomalous variations in a monitored parameter can trigger a real-time fault notification.

Abstract: Battery sub-modules are selecting to electrically connect to a common power bus, including by: determining if a discharge-related fault indication for a given battery sub-module indicates that the given battery sub-module is in a discharge-related fault condition. If so, the given battery sub-module is excluded from the selected battery sub-modules such that said given battery sub-module is electrically disconnected from the common power bus. The selected battery sub-modules are configured so that the selected battery sub-modules are electrically connected to the common power bus; the selected battery sub-modules that are electrically connected to the common power bus are charged.