A heating system includes first and second input ends, first and second battery modules, first switch and second switches, and a control unit. The first switch is connected between first terminals of the first and second battery modules. Second terminals of the first and second battery modules are connected to each other. The second switch is connected between the first input end and the first terminal of the second battery module. The second input end is connected to the first terminal of the first battery module. The first terminals of the first and second battery modules have a same polarity, and the second terminals of the first and second battery modules have a same polarity. The control unit is connected to the first and second switches, and configured to control the first and second switches to be turned on or off.

A heating system includes first and second input ends, first and second battery modules, first switch and second switches, and a control unit. The first switch is connected between first terminals of the first and second battery modules. Second terminals of the first and second battery modules are connected to each other. The second switch is connected between the first input end and the first terminal of the second battery module. The second input end is connected to the first terminal of the first battery module. The first terminals of the first and second battery modules have a same polarity, and the second terminals of the first and second battery modules have a same polarity. The control unit is connected to the first and second switches, and configured to control the first and second switches to be turned on or off.

This invention is related to articles containing a heat source and a heat spreader to conduct heat from the heat source. The heat spreader comprises a core of one or more drawn UHMWPE sheets. The sheets are planar, i.e., have dimensions in two directions that are considerably greater than that of the third dimension. No solvent is used during the drawing process. The draw ratio is typically 100 to 150. The density of a sheet is less than 0.90 g/cm.sup.3. A sheet has good thermal conductivity k.sub.∥ the direction of the draw. k.sub.∥ is at least 30 W/mK. The thermal conductivity perpendicular to the plane of the sheet k.sub.⊥ is greatly reduced. k.sub.⊥ is less than. 0.20 W/mK.

This invention is related to articles containing a heat source and a heat spreader to conduct heat from the heat source. The heat spreader comprises a core of one or more drawn UHMWPE sheets. The sheets are planar, i.e., have dimensions in two directions that are considerably greater than that of the third dimension. No solvent is used during the drawing process. The draw ratio is typically 100 to 150. The density of a sheet is less than 0.90 g/cm.sup.3. A sheet has good thermal conductivity k.sub.∥ the direction of the draw. k.sub.∥ is at least 30 W/mK. The thermal conductivity perpendicular to the plane of the sheet k.sub.⊥ is greatly reduced. k.sub.⊥ is less than. 0.20 W/mK.

In an aspect, a system for battery temperature management in an electric aircraft. In some embodiments, the system includes a plurality of battery cells, comprised of pouch cells. The system includes at least a sensor communicatively connected to a computing device. At least a sensor may be configured to detect temperature. A system also includes a plurality of temperature regulating elements disposed between the plurality of pouch cells. A temperature regulating elements are configured to maintain the temperature of the battery pack. The system also includes a computing device communicatively connected to the plurality of temperature regulating elements. A computing device is configured to determine a target temperature of the plurality of cells and direct the plurality of temperature regulating elements to modify a temperature of the plurality of battery cells as a function of the target temperature.

In an aspect, a system for battery temperature management in an electric aircraft. In some embodiments, the system includes a plurality of battery cells, comprised of pouch cells. The system includes at least a sensor communicatively connected to a computing device. At least a sensor may be configured to detect temperature. A system also includes a plurality of temperature regulating elements disposed between the plurality of pouch cells. A temperature regulating elements are configured to maintain the temperature of the battery pack. The system also includes a computing device communicatively connected to the plurality of temperature regulating elements. A computing device is configured to determine a target temperature of the plurality of cells and direct the plurality of temperature regulating elements to modify a temperature of the plurality of battery cells as a function of the target temperature.

Disclosed is a method and system for detecting faults of a battery heating system and relays. In particular, a method for detecting welding of each relay such as a main relay, a precharge relay or a heater relay and a method for detecting a fault of a battery heating system such as a short circuit, disconnection or damage of each heater are provided by sensing a voltage. In the methods, the on/off state of the heater relay and the high voltage relays is controlled through a predetermined process to detect a fault of the heater relay or the high voltage relay, and welding of the heater relay or the high voltage relay is then detected from a voltage for fault detection which is sensed through a voltage sensing circuit unit for fault detection.

Disclosed is a method and system for detecting faults of a battery heating system and relays. In particular, a method for detecting welding of each relay such as a main relay, a precharge relay or a heater relay and a method for detecting a fault of a battery heating system such as a short circuit, disconnection or damage of each heater are provided by sensing a voltage. In the methods, the on/off state of the heater relay and the high voltage relays is controlled through a predetermined process to detect a fault of the heater relay or the high voltage relay, and welding of the heater relay or the high voltage relay is then detected from a voltage for fault detection which is sensed through a voltage sensing circuit unit for fault detection.

The invention relates to a power management system for supplying backup DC power to peak and/or high current demand battery applications, such as motor starting or an uninterruptible power supply (UPS) used to power a critical load, such as, a data bus or other critical load, after an event, such as loss of primary AC or DC input, during relatively cold ambient temperatures. Two or more heaters can be provided; for example, a low power heater and a high-power heater. In a maintenance mode, the low power heater is used to maintain batteries at a predetermined temperature. In this mode, a battery charger is used to power the low power heater. In a boost mode, after the primary AC or DC input is restored, and battery temperature is too low to back up the critical load, the battery charger supplies power to one or both of the heaters. Since capacity of the battery charger is normally insufficient to heat the batteries to an acceptable operating temperature in a relatively short period of time, a portion of residual power from the batteries is used to boost power to the heaters in order to speed up the time to get each battery of said batteries to its rated operating temperature.

The invention relates to a power management system for supplying backup DC power to peak and/or high current demand battery applications, such as motor starting or an uninterruptible power supply (UPS) used to power a critical load, such as, a data bus or other critical load, after an event, such as loss of primary AC or DC input, during relatively cold ambient temperatures. Two or more heaters can be provided; for example, a low power heater and a high-power heater. In a maintenance mode, the low power heater is used to maintain batteries at a predetermined temperature. In this mode, a battery charger is used to power the low power heater. In a boost mode, after the primary AC or DC input is restored, and battery temperature is too low to back up the critical load, the battery charger supplies power to one or both of the heaters. Since capacity of the battery charger is normally insufficient to heat the batteries to an acceptable operating temperature in a relatively short period of time, a portion of residual power from the batteries is used to boost power to the heaters in order to speed up the time to get each battery of said batteries to its rated operating temperature.