Abstract: Provided are an apparatus and a method for diagnosing an abnormality in a cell balancing circuit. The apparatus may include a floating capacitor charged with voltage of a battery cell, a cell balancing circuit for discharging the floating capacitor, a voltage measuring unit for measuring the battery cell voltage of the charged floating capacitor and a residual voltage of the discharged floating capacitor, and a control unit for determining an abnormality in the cell balancing circuit based on the residual voltage of the discharged floating capacitor.

Abstract: A circuit used to measure cell voltages in a battery pack can include a cell voltage level shifter, a sense block, and a compensation current generator. The cell voltage level shifter selects a cell and shifts the terminal voltages of the selected cell from a first voltage level to a second voltage level. The sense block monitors the current consumed by the level shifter, and generates a signal indicative of the consumed current. The compensation current generator generates compensation currents to compensate the current consumed by the level shifter. Therefore, unbalance of the cell capacities caused by the current consumed by the level shifter can be reduced or eliminated, and thus the overall capacity of the battery pack can be improved.

Abstract: A current detecting device includes a second fixed part to which the harness is fixed and electrically connected, a bus bar as a resistor inserted between a first fixed part and the second fixed part, a circuit board in which a current detection circuit is mounted, the current detection circuit detecting current flowing through the bus bar based on a potential difference between two points along an energizing direction of the bus bar, and a case accommodating the bus bar and the circuit board. The second fixed part to which the harness is fixed and electrically connected is disposed within a battery upper surface area.

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 vehicle has a low voltage power generating unit mounted thereon, which passively generates low voltage power when the vehicle is electrically connected to commercial power supply through coupling of a connector unit. A winding transformer transforms the commercial power supply input to the primary side with a prescribed ratio of transformation, and the transformation is performed without requiring any control signal from the outside. The AC power with voltage lowered, output from the secondary side of winding transformer, is rectified by a diode unit, and a low voltage power is generated. The low voltage power generated by the diode unit is supplied through a supplementary low voltage DC line to a sub battery and to a controller.

Abstract: Battery chargers, electrical systems, and rechargeable battery charging methods are described. According to one aspect, a battery charger includes charge circuitry configured to apply a plurality of main charging pulses of electrical energy to a plurality of rechargeable cells of a battery to charge the rechargeable cells during a common charge cycle of the battery and to apply a plurality of secondary charging pulses of electrical energy to less than all of the rechargeable cells of the battery during the common charge cycle of the battery to charge the less than all of the rechargeable cells.

Abstract: A method of balancing a state of charge (SOC) of a plurality of cells connected in series, including identifying an undercharged cell from the plurality of cells to charge, electrically connecting a positive side of the undercharged cell to a positive bus, electrically connecting a negative side of the undercharged cell to a negative bus, electrically connecting an inductor to a voltage source during a first time period; electrically disconnecting the inductor from the voltage source in response to an elapse of the first time period, and maintaining the disconnection of the inductor from the plurality of cells for a second time period corresponding generally to the time for the inductor to discharge energy to the undercharged cell.

Abstract: A cell balancing software program that executes on a computer system embedded inside a multi-cell battery and includes a means to control an external charging system. When a charge imbalance is detected between the cells, a cell balancing algorithm is selected from a plurality of cell-balancing algorithms and is executed. The executed algorithm causes a charge request, which specifies desired charging parameter(s), to be generated, and the charge request is transmitted to the external charging system. After the external charging system charges the battery according to the charge request, the effectiveness of the cell-balancing algorithm can be evaluated and stored in a history. The history can be used to select cell balancing algorithm(s) for future cell balancing.

Abstract: A system for balancing a plurality of battery pack system modules connected in series comprising: a plurality of battery pack system modules, wherein a high charge module of the plurality of battery pack system modules has a charge greater than a that of other modules. At least one zener diode connected in series with a current limiting resistor is connected in parallel to the plurality of battery pack system modules. A power source is in communication with a disconnect circuit of at least one of the battery pack system modules. The disconnect circuit is actuated when the battery pack system module reaches a predetermined state of charge. The zener diode enables current from the power source to bypass charged battery pack system modules to charge other battery pack system modules.

Abstract: A cell management system and method for balancing energy across a plurality of cells coupled to a circuit bus. The system can include a transformer, two transformer switches, and for each cell, a first switch pair allowing transfer of energy between the transformer and the cell, and a second switch pair allowing removal or inclusion of the cell in the serial connection of cells. The system can include an energy storage device, a switch pair allowing transfer of energy between the transformer and the storage device, and for each cell, a third switch pair allowing transfer of energy between the storage device and the cell. The system can include cell, bus and storage device sensors and state estimators. The system can include a controller that controls the transformer switches, cell switches, and storage device switches based on the sensor readings and states.

Abstract: The invention relates to a traction battery having a first battery cell group and a second battery cell group. A first connection of the first battery cell group is connected to a first battery pole by a charging and disconnecting device, a second connection of the first battery cell group is connected to a first service plug connection, a first connection of the second battery cell group is connected to a second service plug connection, and a second connection of the second battery cell group is connected to a second battery pole by a disconnecting device. The first service plug connection and the second service plug connection can be short-circuited by an external service plug.

Abstract: A battery charging system and method, includes a high voltage charger for charging a group or string of series connected battery cells, and a group of individual cell chargers for charging individual ones of the cells. The charging technique includes detecting at least one cell being charged to a predetermined voltage, and then inhibiting the high voltage charger from further charging any of the cells. The individual cell chargers charge individual ones of the cells, except the at least one cell charged to the predetermined voltage.

Abstract: Apparatus for a modular battery management system with interchangeable slave modules connected to each cell and including a master module controlling and managing the battery system. All the modules receive power through a transfer switch that selectively switches between an external source, an auxiliary source, and the battery. The modules are configured to connect to a cell of the battery for charging and monitoring the cell individually. Each module is electrically isolated from the other modules. The modules are autonomous and shut down the battery and disconnect the module when a critical parameter of the cell is reached. When the battery is in service and a cell parameter approaches the critical level, the master controller instructs the corresponding slave module to charge the cell using battery power. The master module initializes the slave modules to uniquely identify the modules.

Abstract: An apparatus for charging a plurality of series connected battery cells includes first and second input terminals for providing a charging voltage to the plurality of series connected battery cells. A transformer includes a primary side associated with the charging voltage and a secondary side including a plurality of portions. Each of the plurality of portions connected across at least two of the plurality of series connected battery cells. A first switch in series between each of the plurality of portions of the secondary side and a first battery cell of the at least two of the plurality of series connected battery cells provides a charging current to the first battery cell during a first portion of a cycle of a current in the primary side of the transformer.

Abstract: A power supplying apparatus for supplying power to a plurality of loads has been needed. Therefore, a power supplying apparatus for supplying power to a plurality of loads, including: a rectifying circuit connected to each of the plurality of loads; an AC circuit to sequentially connect between the rectifying circuits; and an AC generating circuit to apply AC voltage to the AC circuit, in which the AC circuit includes a capacitor and an inductor connected in series is provided.

Abstract: A system and method dynamically equalizes battery voltages with low inherent power losses in a string of series connected electrochemical batteries. The method includes charging/discharging a group of batteries using magnetic storage in a transformer with bipolar magnetic excursion, individually isolated circuits and pulsed energy transfer. A method also exchanges current between batteries using direct current transfer between them and limiting inductance. Using this method, battery voltage may be measured from an isolated circuit, thus enabling information transfer to a central monitoring system. The method also has the benefit of providing an estimation of battery internal resistance from isolated circuits in the series of batteries.

Abstract: A battery management system includes several subsystem blocks, an Energy Storage Master Charger unit, and several battery pack systems. The Energy Storage Master may interface with the Vehicle Master Controller by way of CAN or other communication method to an External Charger. Each battery module within a battery pack may include a Local Module Unit which may communicate with a Pack Master. The Pack Master may communicate with and may be controlled by the Energy Storage Master. Thus, there is a processor to monitor groups of battery cells, a second processor to collect further information about the cell groups, and a third module that takes high-level information from each cell group processor to process and pass on to other vehicle controllers or charger controllers. An integrated BMS may enable cell monitoring, temperature monitoring, cell balancing, string current monitoring, and charger control integration.

Abstract: A battery pack includes a battery cell, a charge-blocking unit, a voltage sensing and balancing circuit, and a microcomputer, the microcomputer including a controller that detects at least one selected from the group of abnormal analog-to-digital conversion, abnormal voltage, and abnormal temperature of the battery cell, the controller outputting a charge control signal to the charge-blocking unit to inhibit charging of the battery cell.

Abstract: Vehicle alignment for inductive charging includes a control system and logic configured to execute on the control system. The logic is configured to define a first orientation for a first antenna and a second antenna, which are disposed on a vehicle. The logic is also configured to define a second orientation specifying a location of a vehicle charging device disposed on the vehicle relative to the first and second antennae. The logic is further configured to determine a location of an inductive charging device relative to the vehicle by performing triangulation analysis using data from the first and second orientations in conjunction with signals received from the first and second antennae. The logic is also configured to calculate a direction to the location using voltage values from the signals, such that movement of the vehicle in the direction brings the vehicle charging device closer to the inductive charging device.

Abstract: A battery ECU acquires open circuit voltages of a plurality of battery cells that are divided into a plurality of groups A, B, C using a plurality of detecting units, and calculates SOCs of the battery cells based on the open circuit voltages. Then, the battery ECU selects the group to which the battery cell having the largest SOC among the SOCs of the plurality of battery cells belongs, and selects the battery cell to be discharged in the selected group. A series circuit composed of a resistor and a switching element is connected in parallel with each battery cell. The battery ECU turns on the switching element corresponding to the selected battery cell. At this time, the battery cell is connected to the resistor, thus being discharged.

Abstract: The present invention relates to an electric storage unit group, a charger, an electronic device, an electric vehicle, a method for charging the electric storage unit, a method for discharging the electric storage unit group, a method for supplying and receiving power, and a method for determining a charging/discharging route in the electric storage unit group, which can provide a method for charging the electric storage unit group in which a plurality of electric storage units are connected in a desired form. The method for charging the electric storage unit group is a method for charging a rechargeable battery cell in an electric storage unit group in which a plurality of electric storage units having rechargeable battery cells are linearly or reticulately connected. At an upstream side of the electric storage unit group, the electric storage unit group is connected to a power supply for charging the electric storage units.

Abstract: In a battery charger, the rectifier includes rectifying elements provided for respective three phases. The rectifier supplies, for the respective phases, currents for rectifying three-phase AC voltages so as to charge a battery. A voltage detector detects whether or not the battery is charged. Switching units are provided for the respective rectifying elements, and rectify the AC voltages to charge the battery in the off-state. Switch controllers output gate signals in accordance with a timing of zero-cross detection upon receiving a detection signal indicating that all the gate signals for turning on and off the respective switching units for the respective phases are supplied in the order of the phases.

Abstract: Disclosed herein are a method of controlling the operation of battery modules in a battery system, which includes two or more battery modules or battery module assemblies, wherein the battery system further includes energy consuming loads for consuming charged energy, and the method includes, when a specific battery module or a specific battery module assembly is abnormally operated, connecting the abnormally operated battery module or the abnormally operated battery module assembly to the corresponding energy consuming load to forcibly discharge the charged energy, and a battery system that is capable of performing the battery system control method.

Abstract: A lithium battery module with multiple-cells connected in parallel is disclosed. The lithium battery module comprises a battery management unit, a power converter (optional) and each cell with an individual charging control switch and a discharging control switch in series connected with the cell and is independent controlled by the battery management unit so that a charger is capable of charging the designate cell or more or disable one among them.

Abstract: The present invention relates to a system for charge balancing over a plurality of rechargeable energy storage devices coupled in series, said system comprising a plurality of balancing units each assigned to one of the rechargeable energy storage devices, an AC signal generator for providing an AC signal to the plurality of balancing units, and a capacitive coupling between the AC signal generator and each of the plurality of balancing units for common mode rejection. A first balancing unit comprises a plurality of switches for transferring, on the one hand, charge from the AC signal generator or from an energy storage device assigned to another balancing unit for charging the energy storage device assigned to the first balancing unit, and, on the other hand, for transferring charge to the AC signal generator or to an energy storage device assigned to another balancing unit for discharging the energy storage device assigned to the first balancing unit.

Abstract: A battery pack. The battery pack includes a housing, a plurality of terminals, a plurality of lithium-based battery cells, and a controller. The plurality of terminals electrically connect to an electrical device. The electrical device is able to support the battery pack. Each of the plurality of battery cells are individually tapped and have an individual state of charge. The plurality of terminals includes a sense terminal. The controller is operable to monitor a characteristic of each of the plurality of battery cells and to communicate the monitored characteristic of each of the plurality of battery cells to the electrical device via the sense terminal.

Abstract: A multiple cell battery charger configured with a parallel topography is disclosed. In accordance with an important aspect of the invention, the multiple cell battery charger requires fewer active components than known battery chargers while at the same time protecting multiple battery cells from overcharge and discharge. The multiple cell battery charger in accordance with the present invention is a constant voltage battery charger that includes a regulator for providing a regulated source of direct current (DC) voltage to the battery cells to be charged. In accordance with the present invention, each battery cell is connected in series with a switching device, such as a field effect transistor (FET) and optionally a current sensing device. In a charging mode, the serially connected FET conducts, thus enabling the battery cell to be charged. The battery voltage is sensed by a microprocessor.

Abstract: An charging device includes: capacitors connected in series; a charging unit that charges the capacitors; bypass units, each respectively connects in parallel to each capacitors, wherein each bypass unit causes, when a charged voltage of any capacitor has reached a set voltage, a charging current to bypass the capacitor whose charged voltage has reached the set voltage; and a control unit that controls the charging unit to charge the capacitors in such a manner that, when a charging voltage of the any capacitor has reached the set voltage, the control unit causes the charging unit to reduce the charging current, and if a predetermined period has elapsed since the charging voltage has reached the set voltage, and if a charging voltage of any of the other capacitors has not reached the set voltage after the predetermined period, the control unit causes the charging unit to increase the charging current.

Abstract: A method of operating a battery system includes a plurality of battery cells coupled in series. The plurality of cells includes at least three battery cells coupled in series. The method includes determining a cell with the greatest charge excess of the plurality of battery cells. The method further includes determining a cell with the greatest charge deficit of the plurality of battery cells. The method further includes discharging the cell with the greatest charge excess to charge, with a voltage converter, the cell with the greatest charge deficit.

Abstract: A plurality of serially connectable lithium based batteries provide power to a load upon actuation of a user operated switch. Upon actuation of the user operated switch, additional switches intermediate adjacent batteries close to serially connect the batteries to one another and a load. A signal from the load maintains these additional switches closed. A charging circuit is associated with each battery to charge the batteries in parallel upon opening the additional switches. Sensors for temperature, current and various other parameters provide signals to one or more controllers to prevent damage upon the presence of a fault indication signal.

Abstract: A four-stage power distribution system (100) includes (i) a first stage (110) having an inverter (112) that provides power to a frequency drive (114) and an electric motor (116) controlled by the frequency drive; (ii) a second stage (120) having a flywheel (122) driven by the motor; (iii) a third stage (130) having an alternator (132) driven by the motor (116) and connected to the flywheel, and a rectifier (134) that receives current from the alternator and generates a direct current; and (iv) a fourth stage (140) having a charge control switch (142) that receives power from the rectifier, and a plurality of power storage devices such as batteries (144A-144C). A master control switch (150) controls the charge control switch to transition the plurality of batteries individually between a charging configuration and a load configuration. One or more of the battery(ies) in the load configuration provides power to the inverter.

Abstract: A cell balancing circuit with a self-balancing function and a secondary battery with the cell balancing circuit, the cell balancing circuit includes a balancing unit provided for every two adjacent unit cells among the unit cells. The balancing unit includes a discharge unit and a voltage-dividing unit. The discharge unit sets a discharge path to discharge only the unit cell with the higher voltage among the two adjacent unit cells. The voltage-dividing unit uses the voltages of the two adjacent unit cells to provide an enable signal to the discharge unit.

Abstract: The battery fault determination apparatus includes battery monitor sections connected in a daisy chain, each of which is provided for a corresponding one of unit batteries each including battery cells connected in series to monitor the battery cells and output an output signal indicative of a monitoring result, and a control section configured to output a control signal to the battery monitor sections. The control signal and the output signal are cascaded through the battery monitor sections causing each battery monitor section to perform a state change between a state to monitor overcharge of the battery cells and a state to monitor wire breakage. Each battery monitor section is configured to receive the control signal from the immediately upstream-side battery monitor section, make a detection whether the state change has been performed correctly, and output the output signal including a detection result to the immediately downstream-side battery monitor section.

Abstract: When charge power or discharge power of each individual sodium-sulfur battery included in a plurality of sodium-sulfur batteries becomes 1/n (n is a natural number) or less of a rated output, individual sodium-sulfur batteries are sequentially stopped. This prevents the discharge power (or the charge power) of the sodium-sulfur battery from becoming minute, so that a battery depth (or a stored energy) of the sodium-sulfur battery can be accurately managed.

Abstract: A charge indicator circuit for indicating an electronic device charged by an inputted charge electric potential includes an interface unit, a switch unit connected to the interface unit; a processor unit connected to the switch unit, and an indicator unit connected to the switch unit. The charge electric potential is inputted into the charge indicator circuit from the interface unit and powers the indicator unit to emit light when the processor unit is switched off, and the processor unit detects the charge status of the electronic device and controls the switch unit according to the detect results when the processor unit is switched on.

Abstract: A management unit and method for managing electric energy stored in a battery composed of a number of series-connected cells, the management unit having: a main equalizing circuit, which forms the primary of an electric transformer and has a constant alternating-current generator powered by the battery and which feeds alternating current of constant intensity through the main equalizing circuit; and, for each cell of the battery, a secondary equalizing circuit, which forms the secondary of the electric transformer, is connected parallel to the cell, has a one-way electronic device which imposes electric current flow to the cell in one direction only, and is connected to a drive device that can be activated to zero the voltage applied to the cell by the secondary equalizing circuit.

Abstract: An electrochemical battery system in one embodiment includes a first electrochemical cell, a second electrochemical cell, a memory in which command instructions are stored, and a processor configured to execute the command instructions to (i) selectively charge or discharge the first electrochemical cell based upon an evaluation of first criteria associated with the first electrochemical cell, and (ii) selectively charge or discharge the second electrochemical cell based upon an evaluation of second criteria associated with the first electrochemical cell.

Abstract: Systems and methods are herein disclosed for efficiently and cost-effectively balancing the voltages across batteries and/or cells in an energy storage system. A controller monitors the battery voltages and instructs regulator circuits to balance voltages between any batteries or sets of batteries having imbalanced voltages. Regulator circuits implementing a modified ?uk converter can be utilized. Regulator circuits can have two capacitive circuits, one inductive circuit, and two switches. Two capacitors, an inductor, and two field effect transistors can be used in each regulator circuit.

Abstract: A battery management system and method, the method including balancing cells and measuring the cell voltages of cells that are not directly adjacent to the cells being balanced.

Abstract: A battery equalization system has two accumulator stages in series, each including an accumulator, and ±poles, a voltage generator for each accumulator stage, and an associated charging device powered by the generator. The charging device includes an inductor and capacitors. One capacitor connects to the generator's positive pole, the other connects to its negative pole, a first diode, whose anode connects to a negative pole of the accumulator stage and whose cathode connects to the first capacitor, a second diode whose anode connects to the negative pole of the accumulator stage and whose cathode connects to the second end of the second capacitor, and a switch connected to the inductor and to the positive pole of the accumulator stage, and a control device that controls the generator, closes the switch and causes the inductor to stores energy and to transfer it to the associated accumulator stage.

Abstract: An equalization system for batteries has two series-connected accumulator stages connected, each including an accumulator, a voltage generator including positive and negative poles, for each stage, an associated charging device supplied by the voltage generator. The charging device includes an inductor having a first and second ends, and a capacitor having first and second ends. The capacitor's first end connects to the generator's positive pole. It also has a diode whose anode connects to a negative pole of the accumulator stage and whose cathode connects to the inductor's first end. It also has a switch whose first end connects to the inductor. And it also has a control device that controls the generator and closes a switch of a charging device associated with an accumulator stage to be charged so that the inductor stores energy, and causes its transfer to that accumulator stage.

Abstract: A battery alarm for use with a battery assembly is provided, the battery alarm including a first activation component, a signaling component, and an output component. The first activation component is configured to activate the alarm upon disengagement of the battery assembly from a battery-operated device and is further configured to deactivate the alarm upon engagement of the battery pack with the battery-operated device. The signaling component is coupled to the first activation component and is configured to transmit a signal when the alarm is activated. The output component is adapted to receive the signal from the signaling component and is configured to produce a visual, audible, and/or tactile output upon receipt of the signal from the signaling component.

Abstract: A cell management system and method for balancing energy across a plurality of cells coupled to a circuit bus. The system can include a transformer, two transformer switches, and for each cell, a first switch pair allowing transfer of energy between the transformer and the cell, and a second switch pair allowing removal or inclusion of the cell in the serial connection of cells. The system can include an energy storage device, a switch pair allowing transfer of energy between the transformer and the storage device, and for each cell, a third switch pair allowing transfer of energy between the storage device and the cell. The system can include cell, bus and storage device sensors and state estimators. The system can include a controller that controls the transformer switches, cell switches, and storage device switches based on the sensor readings and states.

Abstract: The invention relates to a circuit assembly (10), comprising a series connection of first and second battery units (11, 12), wherein first and second battery units (11, 12) are arranged alternately, a first inductive storage element (13), wherein in a primary phase first inputs (17) of the first battery units (11) can be connected to a first terminal (19) of the first inductive storage element (13) by means of a first switch assembly (16) and second inputs of the second battery units (18) can be connected to a second terminal (20) of the first inductive storage element (13) by means of the first switch assembly (15), a second inductive storage element (14) which is inductively coupled to the first inductive storage element (13), wherein in a secondary phase by means of a second switch assembly (16) a first terminal of the second inductive storage element (14) can be connected to a first or a second input and a second terminal of the second inductive storage element (14) can be connected to a second or a first

Abstract: An electrochemical battery system in one embodiment includes a plurality of first electrochemical cells, a memory in which command instructions are stored, and a processor configured to execute the command instructions to (i) evaluate each of the plurality of first electrochemical cells, and (ii) selectively connect a first of the plurality of first electrochemical cells to a power provider based upon the evaluation while selectively isolating a second of the plurality of first electrochemical cells from the power provider based upon the evaluation.

Abstract: A solar powered hybrid power system including a solar charge collector; a charge storage system comprising at least a first charge storage device adapted to receive and store charge from said solar charge collector; wherein said charge storage system further comprises a power electronic circuit selectively connectable to at least a second charge storage device, said power electronic circuit adapted to transfer said stored charge to said at least a second charge storage device at a selectable voltage level.

Abstract: A balancing method for a battery pack includes balancing battery cells near an end of discharge. A deep discharge of the battery cells can be prevented without using an overdischarge control unit. One battery cell balancing method includes: a balancing check condition determination step for determining whether or not a maximum voltage out of voltages of the battery cells is smaller than a reference voltage; a balancing start condition determination step for determining whether or not a residual capacity difference or voltage difference between the individual battery cells exceeds a reference value; a balancing time calculation step for calculating a balancing time for discharging the battery cell that exceeds the reference value; and a balancing operation step for discharging the selected battery cell when the battery cells are under charge or are at rest or when a discharge current of the battery cells is smaller than a reference current.

Abstract: A cell balance control device includes a battery monitor unit, a cell balance unit, and an ECU, and equalizes serially connected chargeable battery cells in a battery loaded into a vehicle. The battery monitor unit detects the voltage of each battery cell. The cell balance unit equalizes the voltages of the plurality of battery cells based on the voltage of each battery cell detected by the battery monitor unit. At least one of the times when an idling stop state of the vehicle starts, when the charging operation of the battery starts, and when the charging operation of the battery terminates triggers the ECU allowing the cell balance unit to equalize the voltage of the plurality of battery cells.

Abstract: Designs for a battery-powered, all-electric locomotive and related locomotive and train configurations are disclosed. In one embodiment, a locomotive may be driven by a plurality of traction motors powered exclusively by a battery assembly which preferably comprises rechargeable batteries or other energy storage devices. The locomotive carries no internal combustion engine on board and receives no power during operation from any power source external to the locomotive. A battery management system monitors and equalizes the batteries to maintain a desired state of charge (SOC) and depth of discharge (DOD) for each battery. A brake system may be configured to prioritize a regenerative braking mechanism over an air braking mechanism so that substantial brake energy can be recovered to recharge the battery assembly.

Abstract: A rechargeable battery has a plurality of cell strings each having a plurality of rechargeable electrochemical cells connected in series, and a plurality of charge regulators each connected in series with one of the cell strings. Each charge regulator is adapted to limit a charge voltage or current applied to the cell string based on a determined top-of-charge voltage for each cell string. In an embodiment, the rechargeable battery has a monitoring system to sense an operating parameter of the cell string and determine the top-of-charge voltage, and each of the charge regulators includes a charge voltage controller in communication with the monitoring system. In another embodiment, the rechargeable battery has discharge regulators each connected in series with one of the cell strings, and adapted to limit a discharge voltage or current from a given cell string based upon at least one monitored parameter of the cell string.