Abstract: A power storage device is electrically connected to a first input and output end located on the opposite side of a direct-current common section in a second power converter. According to an input form of electric power, a first power converter operates as a DC/AC converter or an AC/DC converter. The second power converter operates as a DC/AC converter, an AC/DC converter, or a DC/DC converter. The power storage device is charged using direct-current power supplied from the direct-current common section or the first input and output end side. The power storage device discharges desired direct-current power to the direct-current common section or the first input and output end side. A control device freely adjusts, according to the input form of the electric power, the voltage of the direct-current common section to a desired voltage including a high voltage or a low voltage.

Abstract: The system includes a first and a second power supply terminal configured to have at least one of a battery and a generator connected thereto, a first external terminal coupled to the first power supply terminal, and a second external terminal coupled to the second power supply terminal, and a protection unit connected between the first external terminal and the first power supply terminal. The protection unit includes a semiconductor switching unit having a load path and a control terminal, the load path connected between the first external terminal and the first power supply terminal, and a control circuit coupled to the control terminal of the semiconductor switching unit and configured to switch the switching unit on and off dependent on at least one electrical parameter in the on-board power supply system.

Abstract: An ECU is mounted on a vehicle equipped with a converter that can boost a voltage of a power storage device storing electric power for obtaining driving force to output the boosted voltage to a drive load device. The ECU starts boosting at the converter upon satisfaction of at least any of a first condition that a boost request signal Req is received (that is, an output voltage request value of the converter exceeds a voltage Vb of the power storage device) and a second condition that output electric power P of the power storage device is higher than a value obtained by subtracting charge electric power ?P transiently occurring at the start of boosting from rated electric power Wout (that is, it is predicted that output electric power P will exceed rated electric power Wout in response to the start of boosting).

Abstract: In a method and a device for controlling hybrid functions in a motor vehicle, including at least one control unit, hybrid functions of a motor vehicle are controlled by the control unit, the control unit switching off at least one hybrid function above a predetermined battery temperature.

Abstract: A vehicle anti-theft device (60) contains: a case body (132); a lid member (156) for closing the opening (167) of the case body; a substrate (67) which is inserted in a removable manner into the case body (132) from the opening thereof and on which electronic components are mounted; a sub-battery (88) for supplying power to the substrate (67); and a sealing member (157) which is fitted into the opening (167) of the case body and has a substrate pressing part (203) for preventing the substrate from being extracted and a sub-battery pressing part (204) for preventing the sub-battery (88) from being extracted.

Abstract: An embodiment of an electrical system of a vehicle with electric propulsion achieved by at least one electrical machine; the electrical system has: a storage section provided with at least one battery including of a plurality of cells, each of which is coupled in series with the other cells and is provided with a bypass branch that is coupled in parallel to the cell and has a bypass switch; a section of traction that interacts with the electric machine and is equipped with a power electronic converter that exchanges electrical energy with the storage section; and a section of the auxiliaries, which powers auxiliary services of the vehicle, has a buffer battery and is electrically powered by the storage section; a first connector switch coupling the storage section to the section of traction; and a second connector switch coupling the storage section to the section of the auxiliaries.

Abstract: A safety device for a high-voltage component including a cover that covers at least a part of the high-voltage component, a low-voltage circuit that controls a conduction/shut-off state of an electric circuit for supplying power to the high-voltage component, and a selecting unit that selects the conduction/shut-off state of the low-voltage circuit by an operation accompanying an attachment/removal work of the cover.

Abstract: An electric cut-off safety device for the power circuits of an electric bipolar vehicle is capable of cutting off two poles. An electric vehicle can include such an electric cut-off safety device.

Abstract: In an embodiment, a medium voltage drive system includes a transformer, multiple power cubes each coupled to the transformer, and a manifold assembly. Each power cube includes cold plates each coupled to a corresponding switching device of the cube, an inlet port in communication with a first one of the cold plates and an outlet port in communication with a last one of the cold plates. The manifold assembly can support an inlet conduit and an outlet conduit and further support first and second connection members to enable blind mating of each of the first connection members to the inlet port of one of the power cubes and each of the second connection members to the outlet port of one of the power cubes to enable two phase cooling of the plurality of power cubes.

Abstract: The power source apparatus has high-voltage-side power supply circuitry 4 that supplies driving battery 1 power to the first measurement circuit 2 and the second measurement circuit 3, isolation circuitry 5 that isolates output from the first measurement circuit 2 and the second measurement circuit 3 and outputs it to the vehicle-side, and low-voltage-side power supply circuitry 6 that supplies vehicle auxiliary battery 7 (12V) power to the isolation circuitry 5. The first measurement circuit 2, which is powered by the high-voltage-side power supply circuitry 4, outputs voltage signals to the vehicle-side via the first isolation circuit 5A, which is powered by the first low-voltage-side power supply circuit 6A, and the second measurement circuit 3, which is powered by the high-voltage-side power supply circuitry 4, outputs battery 10 error signals to the vehicle-side via the second isolation circuit 5B, which is powered by the second low-voltage-side power supply circuit 6B.

Abstract: A battery is protected without realizing the state of every vehicle element connected to the battery or the battery input/output current. A current limit value setting unit sets a current limit value for limiting the battery input/output current in accordance with state of the battery. A limiting current ratio calculation unit calculates a ratio of the current limit value set by the current limit value setting unit to a detected battery current value. A request limit coefficient calculation unit calculates a limit coefficient for limiting a request value for driving respective vehicle components based on the ratio calculated by the limiting current ratio calculation unit. In addition, a final request value calculation unit calculates as a final request value for the respective vehicle components, respective multiplication values resulting from multiplying the respective request values for the respective components by the limit coefficient calculated by the request limit coefficient calculation unit.

Abstract: An electrical conductor is provided that includes at least one strip of conductive material defining a length and having a first end with a first cutout and a second end having a second cutout. The cutouts engage electrical terminals. The at least two deflections are orthogonal to the length of the strip. The deflections are located between the first cutout and the second cutout and are in plane or out of plane of the cutouts. The electrical conductor is particularly well suited for interconnection of batteries associated with a vehicle power system.

Abstract: A vehicle power source apparatus is provided with a driving battery mounted in a vehicle, an auxiliary apparatus battery that supplies electric power to an auxiliary apparatus of the vehicle, a DC power conversion unit that supplies electric power from the driving battery to the auxiliary apparatus battery, a control unit that controls the DC power conversion unit, a driving battery harness that connects the driving battery with the DC power conversion unit and is protected by a shield, an auxiliary apparatus battery negative-side harness that connects the DC power conversion unit with the negative side of the auxiliary apparatus battery, and a voltage sensor that detects a connection abnormality in the auxiliary apparatus battery negative-side harness.

Abstract: An electric vehicle running control system is provided. The electric vehicle running control system comprises: a heating circuit (11); a load capacitor (C12); a switchgear (20) connected with the heating circuit (11) and the load capacitor (C12) respectively; and a switch control module (200) connected with the switchgear (20) for controlling the switchgear (20) to switch off when the heating circuit (11) is connected with an in-vehicle battery (5) to form a heating loop for heating the in-vehicle battery (5).

Abstract: A method is described for controlling a voltage limit for a maximally permissible operating voltage in an on-board electrical system of a vehicle, including the step of adapting the voltage limit in dependence on vehicle data, wherein an actual voltage is ascertained and the actual voltage is short-circuited or limited if the actual voltage exceeds the voltage limit. Also described is a device for controlling a voltage limit for a maximally permissible operating voltage in an on-board electrical system of a vehicle, having an adaptation device for adapting the voltage limit in dependence on vehicle data.

Abstract: A power supply device for a vehicle has connection changeover means for alternatively changing a connection of a capacitor and a battery over to any one of a parallel connection of the capacitor and the battery, a series connection of the capacitor and the battery and an independent connection of the capacitor and the battery. Electrical power is selectively supplied to a electric supercharger by any one of a parallel connection circuit of the capacitor and the battery, a series connection circuit of the capacitor and the battery and an independent connection circuit of the capacitor and the battery whose connection of the capacitor and the battery are alternatively changed over to by the connection changeover means.

Abstract: An idling stop apparatus is provided which can prevent a voltage of a battery from being lowered even when a microcomputer is reset. In an idling stop apparatus when a reset condition is established, reset information indicating that the reset condition is established is stored in a latch circuit and a microcomputer disables an idling stop function when the reset information is stored. The reset information is stored in the latch circuit even when the microcomputer is being reset or even after the microcomputer is reset. Accordingly, the microcomputer after the reset can disable the idling stop function. As a result, it is possible to prevent the voltage of the battery from being lowered due to the idling stop function.

Abstract: A system and method for controlling battery conditions. The system includes a network access device battery. The network access device battery powers a network access device. A heating element may be connected to the network access device battery. The heating element may be a resistive load for determining a status of the network access device battery or the heating element may be activated based on a heating schedule.

Abstract: In an electric vehicle, high-power unit (20) disposed in motor room (2) to supply drive current to motor drive unit (10), and battery pack (30) disposed below vehicle body floor (3) are connected to each other through charging/discharging harness (51). High-power unit 20 includes unit back surface (high-power module back surface) (24) that faces dash panel (4), and harness connection concave portion (25) recessed from unit back surface (24) toward an inside of high-power unit (20), wherein charging/discharging harness connection terminal (26) to which one end (51a) of charging/discharging harness (51) is connected is disposed inside of harness connection concave portion (25).

Abstract: A battery system includes batteries; a voltage detector linking batteries and detecting batteries' voltage; an equalizer linking batteries and fine-tuning their charging/discharging efficiency; a battery protection board on which there is a MCU used to receive signals from the voltage detector for characteristic differences between batteries balanced by the equalizer and batteries with similar charging and discharging efficiency; a digital interface connected between the MCU and an upper-level control system as one interface of signal transmission.

Abstract: A signal representing a numerical value from a vehicular application is received. A power value is calculated and the power value is a predetermined based raised to the power of the numerical value. The calculating using multiplication and shifting operations and the calculating further accesses a look-up table stored in a memory. The calculated power value is returned to the vehicular application. At the vehicular application, the calculated power value is utilized in a calculation and a result of the calculation is obtained. A parameter of the vehicular application according is altered to the result.

Abstract: Disclosed is an electrical leakage diagnosis apparatus for a vehicle which uses an insulation resistance sensor. The apparatus includes an insulation resistance sensor; a main switching part; and a battery power management part configured to terminate the operation of a driving part so as to control a driving motor of a vehicle when the value of a first insulation resistance outputted from the insulation resistance sensor is less than a previously set threshold value, and to determine that an insulation breakage has occurred in one or more driving components when the value of a second insulation resistance, measured after terminations of the driving components, exceeds the threshold value and to terminate the operation of the vehicle by turning off the main switching part so that electrical power supplied from the high voltage battery to the electrical field loads of a vehicle is disconnected.

Abstract: An automotive lamp device is provided. The automotive lamp device includes a lamp housing into which a first lamp or a second lamp is inserted and which includes a plurality of lines, and a lamp driver module which is connected to a first line among the plurality of lines, supplies a first level of voltage and/or current to the first lamp if the first lamp is inserted into the lamp housing, and supplies a second level of voltage and/or current to the second lamp if the second lamp is inserted into the lamp housing.

Abstract: A battery pack that electrically connects a terminal cover, which is attached to a terminal base, and a battery pack case even if the terminal cover and case are not in direct contact with each other. The case is formed from a conductive material and accommodates a battery. The terminal base is formed from a non-conductive material and attached to the case. The terminal cover is formed from a conductive material and attached to the terminal base. A conductor formed from a conductive material comes in contact with both of the terminal cover and the case.

Abstract: Improved protection for a rechargeable battery from damage by being discharged below a cut-off voltage is provided. The measured voltage of a battery under load is lower than the measured voltage of the battery under no load. As the cut-off voltage for the battery is specified as a no load voltage, comparing the measured voltage of the battery under load to the cut-off voltage would result in stopping use of the battery with useable charge remaining. Through testing, a set of relationships for estimating the no load voltage of a battery under load has been determined. Using this set of relationships with battery measurements, an estimated no load voltage for the battery is determined. This estimated no load voltage is compared to the cut-off voltage. This allows for full use of the battery while stopping use of the battery when its voltage reaches the cut-off, thereby preventing damage.

Abstract: Vehicle-related messaging methods and systems are disclosed herein. In one of the methods, a telematics unit disposed in a vehicle detects that the vehicle is no longer in operation. Upon making the detection, the telematics unit automatically transmits a message to a device, where the message includes a suggestion, a recommendation, an indication, or a notification pertaining to a vehicle utility. An application resident on the device, or on a cloud computing system in communication with the device, presents the message on the device by displaying i) the suggestion, the recommendation, the indication, or the notification and ii) a plurality of actionable items associated with the suggestion, the recommendation, the indication, or the notification.

Abstract: A hybrid vehicle comprises an internal combustion engine, a traction motor, a starter motor, and a battery bank, all controlled by a microprocessor in accordance with the vehicle's instantaneous torque demands so that the engine is run only under conditions of high efficiency, typically only when the load is at least equal to 30% of the engine's maximum torque output. In some embodiments, a turbocharger may be provided, activated only when the load exceeds the engine's maximum torque output for an extended period; a two-speed transmission may further be provided, to further broaden the vehicle's load range. A hybrid brake system provides regenerative braking, with mechanical braking available in the event the battery bank is fully charged, in emergencies, or at rest; a control mechanism is provided to control the brake system to provide linear brake feel under varying circumstances.

Abstract: A security architecture, a battery, and a motor vehicle that has a corresponding battery are configured to be used to combine battery packs of a lower security integrity level into a battery system that has a higher security integrity level. The security architecture is for at least two batteries and each battery includes at least one electrochemical cell. The at least two batteries are each combined with at least one data processing unit to form a respective module. The security architecture is configured such that input signals of at least one second module are processed by the at least one data processing unit of at least one first module.

Abstract: A battery protection circuit for connection to a vehicle's auxiliary battery, auxiliary battery load and chassis battery that is connected to the vehicle's alternator. A switching control circuit, including a digital processor, has a voltage sensing circuit connected to the alternator, a voltage sensing circuit connected to the auxiliary battery, a ground terminal for connection to the vehicle's common ground and outputs for controlling switches. An electrically controlled first switch is interconnected between the alternator and the auxiliary load. The first switch has a control input terminal connected to an output of the control circuit for being switched between a closed state and an open state. An electrically controlled second switch is interconnected between the auxiliary load and the auxiliary battery. The second switch has a control input terminal connected to an output of the control circuit for being switched between a closed state and an open state.

Abstract: Disclosed is a dark current cutoff system and method for a vehicle junction. In particular, a controller is configured to monitor signal input through a CAN communication module to determine when other modules in the vehicle are in a sleep mode, cut off battery power to a load device by turning off a switching element when the controller determines that the other modules in the vehicle are in sleep mode, and forcibly maintains an off state of the switching element for a set period time after the power has been cut, regardless of signal input through the CAN communication module.

Abstract: In order to discharge electrical charges from a smoothing capacitor even if no discharge command is issued by a control system, making use of the displacement of a power unit in the event of a collision, a movable electrode is connected to a first contact connected to a high-potential bus, and the smoothing capacitor is connected with a converter and an inverter to be in parallel in the case where an engagement rod is positioned by a retaining ring. Further, when the engagement rod is disengaged from the retaining ring and removed from a relay, the movable electrode is held in contact with a second contact by a pressure spring, and the electrical charge remaining in the smoothing capacitor is discharged to a low-potential bus through a discharge portion.

Abstract: A vehicle having an electricity accumulator for driving a vehicle, a charging inlet for receiving power supplied from a power supply provided on the outside of the vehicle, a circuit for charging the electricity accumulator with power from the power supply, and power lines for connecting the charging inlet and the charging circuit. An abnormality detector of vehicle having a circuit for applying a test voltage to the power lines, and an ECU as a short circuit detecting section. When the voltage value of the power line deviates from a predetermined normal range including the test voltage value although the test voltage is applied to the power line from the voltage application circuit, the ECU detects short circuit of the power line. The ECU specifies a short circuit mode corresponding to the detected short circuit among a plurality of short circuit modes based on the voltage value of the power line.

Abstract: An electrically-driven vehicle 10 comprises a chargeable and dischargeable battery 20, a charger 16 that charges the battery 20 using a supply of electric power from an external power supply 100, an accessory unit 19 that is driven by a supply of electric power from at least one of the battery 20 and the charger 16; and a PM-ECU 18 that controls drive of the charger 16 so that the charged amount of the battery does not exceed a predetermined charging upper limit. The PM-ECU 18 sets the charging upper limit used when the accessory unit 19 is being driven, lower than the charging upper limit used when the accessory unit 19 is not being driven in order to avoid overcharging when excessive electric power is supplied from the accessory unit 19 to the battery 20.

Abstract: The present disclosure relates to a battery including a voltage-measuring apparatus, at least one reversible disconnection apparatus, and a circuit of electronic components. The voltage-measuring apparatus is configured to determine a battery voltage. The at least one reversible disconnection apparatus is configured to electrically disconnect the battery from an electrical supply system, such that the disconnection can be cancelled again, for charging or discharging the battery. The circuit of electronic components is a circuit configured to open the disconnection apparatus in the event of an undervoltage and/or an overvoltage of the battery.

Abstract: The present invention relates to a high voltage battery cooling control technique that improves the operational stability of a high voltage battery by decreasing the likelihood that the battery will overheat due to the indoor air temperature of the vehicle.

Abstract: When it is determined that a charge controllable vehicle and a charge uncontrollable vehicle coexist are connected to a plurality of charging stations, available power X is distributed and supplied to the charge controllable vehicle or the charge uncontrollable vehicle so that total power derived from the charge controllable vehicle and the charge uncontrollable vehicle does not exceed the available power X of a power supply unit, and the available power X is distributed as time division and supplied to the charge controllable vehicle and the charge uncontrollable vehicle.

Abstract: A method is provided for controlling a power supply system of an automotive vehicle that includes at least one battery and at least one associated battery managing unit adapted to monitor the state of charge of the battery. During an off state of the vehicle, the state of charge level of each battery is monitored by the battery managing unit. If the state of charge monitored reaches a low state of charge threshold, an on-board communication device adapted to emit a critical state of charge level alarm to be received by an off-board reception device is activated. The power supply system includes a battery managing unit per battery and an alarm to emit a critical state of charge level alarm.

Abstract: A method of balancing current in a vehicle electric system having a system bus, a first battery, a first bi-directional battery voltage converter selectively transferring a first current between the first battery and the system bus, a second battery, a second bi-directional battery voltage converter selectively transferring a second current between the second battery and the system bus, and a controller controlling the first bi-directional battery voltage converter and the second bi-directional battery voltage converter. The method includes sensing the first current and sensing the second current. The first bi-directional battery voltage converter and the second bi-directional battery voltage converter are controlled so that the first current and the second current are equal portions of a load current supplied to an electrical load connected to the system bus.

Abstract: A control device for a vehicle includes: a charge control portion that adjusts an upper limit of charging power to a battery to prevent a negative electrode potential of the battery from dropping to a lithium reference potential, based on a charge/discharge history of the battery; a braking control portion that detects a sharing ratio between hydraulic braking force by a braking device and regenerative braking force for desired braking force according to a brake pedal depression amount so that a motor generator generates a regenerative braking force within a range of the adjusted upper limit of charging power; and a setting portion that variably sets, according to the hydraulic response rate detected by the detection portion, a degree of limitation of the upper limit when restricting charging current to the battery by restricting the upper limit.

Abstract: An electrical interlock system for including a power takeoff device operable in a first state to transfer mechanical energy from an associated combustible engine to an associated electric motor and/or generator and operative in a second state to prevent the transfer of mechanical energy from the associated combustible engine to the associated electric motor and/or generator. A relay having a first switch and an energizable portion, is coupled to the power takeoff device, the electric motor and an associated power source, such that when the energizable portion is receiving electrical power from the associated power source, the power takeoff device is in the first state and when the energizable portion is not receiving electrical power from the associated power source, the power takeoff device is in the second state.

Abstract: A method is described for monitoring a charging process of a battery, in which cell voltages of a plurality of battery cells are measured at regular time intervals, and loading of the battery by a process of switching on an additional electrical load is prevented if the measured cell voltage of one battery cell exceeds a predetermined cell voltage threshold value. A motor vehicle is also described, which is configured to carry out the method according to the disclosure during a battery charging process. In addition, a battery system is described, in which a controller is configured to determine an estimated value as a function of measured battery parameters during a charging process of the battery. The estimated value corresponds to the maximum temperature in the battery if the charging process is continued without interruption.

Abstract: A battery module includes a battery block and a printed circuit board. The battery block includes a plurality of laminated battery cells. A detection circuit and an amplification circuit are mounted on the printed circuit board. In the battery block, a bus bar is attached to electrodes of the two battery cells in close proximity to each other so that the plurality of battery cells are connected in series. The bus bar attached to one of the electrodes of the battery cell at one end of the battery block is used as a shunt resistor for current detection. The detection circuit detects a voltage between both ends of the shunt resistor, which has been amplified by the amplification circuit.

Abstract: A reverse polarity protection circuit includes a p-channel MOSFET, an n-channel MOSFET, zener diodes, a coil that suppresses a backward flow of an electric current, a resistor that retains a voltage difference between a source of the p-channel MOSFET and a drain of the n-channel MOSFET, a resistor that protects the circuit if short-circuit destruction of the p-channel MOSFET occurs, a resistor that protects the circuit if short-circuit destruction of the n-channel MOSFET occurs, an electrolytic capacitor that suppresses fluctuation in an input voltage to a power supply control IC, a battery that supplies a voltage to an ECU, and the power supply control IC that generates a voltage for causing an IC in the ECU to operate.

Abstract: When a vehicle is “off” many electrically powered devices will continue to draw power from the battery, which will eventually deplete the battery. Instead of leaving such devices on, when the engine is shut off, a message is transmitted from a vehicle's telematics communications device to one or more of: the operator, a telematics service provider or elsewhere, and which notifies the recipient of the power-down condition. The recipient of the message can thereafter respond with a directive that tells the telematics communications device which devices to leave powered on, turn off or schedule to be shut off. Absent such a message, the system powers down devices according to a default power down ordering.

Abstract: A battery augmentation system and method is disclosed. It is particularly designed for the augmentation of batteries in electric or hybrid vehicles. The system comprises of conversion means operatively connected between an auxiliary power system and a electric-motor-battery of the vehicle, wherein the conversion means converts an output signal from the auxiliary power system into a converted signal. The converted signal supplements the electric-motor-battery output voltage preventing it from dropping below a predefined level, thus preventing damage to the electric-motor-battery. The system makes further use of an external battery which can be charged either by mains power or through the auxiliary power system of the electric/hybrid vehicle allowing the vehicle to be converted to a plug-in capable hybrid/electric vehicle.

Abstract: A relay is provided in a power supply line from a battery to a motor of a starter in a vehicle. The relay is selectively switched between a contact side state where contacts short-circuit and a resistor side state where the contacts open and a resistor is inserted into the power supply line in series. When an engine is started, an ECU controlling the starter energizes the motor by driving the relay to the resistor side only for a first predetermined time in order to suppress inrush current and voltage fall due to the inrush current. The ECU detects a contact side state fixation abnormality of the relay based on a battery voltage at the time when the motor is energized by driving the relay to the resistor side.

Abstract: A vehicle, in particular a hybrid and/or electric vehicle, includes a main switch for a power supply which main switch can be operated from outside the vehicle, and a safeguard which safeguards the main switch against unauthorized operation. A method for operating a vehicle includes operating a main switch for a voltage supply of the vehicle from outside the vehicle, wherein the main switch is safeguarded against unauthorized operation by a safeguard.

Abstract: A control system for a parallel battery connection circuit has a plurality of secondary battery packs connected in parallel to each other, in which small batteries are combined and provided substantially equivalently to each other. The control system performs abnormality detection by detecting and comparing states of the secondary battery packs. The control system has state detecting circuits and a control circuit. The state detecting circuits detect currents or temperatures and are provided respectively in the secondary battery packs. The control circuit performs current limitation based on a magnitude of deviation between a deviation in either of a comparison of currents detected corresponding to the secondary battery packs by the state detecting circuits or a comparison of temperatures detected corresponding to the secondary battery packs by the state detecting circuits, and a predetermined judgment value.

Abstract: A vehicle battery management system and method includes a battery, a battery sensor for measuring a condition of the battery and an electronic control unit that receives a signal from the battery sensor corresponding to the condition of the battery. The electronic control unit selectively connects and disconnects that the battery from each of: at least one accessory load and at least one other load. The at least one other load is disconnected from the battery when the vehicle is in a shipping mode and the at least one accessory load is connected to the battery when the vehicle is in an accessory ON mode. The electronic control unit disconnects the at least one accessory load from the battery when the vehicle is in the accessory ON mode and in the shipping mode when the signal indicates that the condition of the battery is below a predetermined threshold.

Abstract: A battery module for use with a vehicle electrical system. The battery module includes a bi-directional battery voltage converter, a first battery, and a second battery. A first relay selectively connects the first battery to the bi-directional battery voltage converter. A second relay selectively connecting the second battery to the bi-directional battery voltage converter. A controller selectively energizes the first relay, selectively energizes the second relay, and controls a direction of current through the bi-directional battery voltage converter.