Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L53/00—Methods of charging batteries, specially adapted for electric vehicles; Charging stations or on-board charging equipment therefor; Exchange of energy storage elements in electric vehicles
  • B60L53/10—Methods of charging batteries, specially adapted for electric vehicles; Charging stations or on-board charging equipment therefor; Exchange of energy storage elements in electric vehicles characterised by the energy transfer between the charging station and the vehicle
  • B60L53/14—Conductive energy transfer
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L50/00—Electric propulsion with power supplied within the vehicle
  • B60L50/50—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells
  • B60L50/60—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells using power supplied by batteries
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L53/00—Methods of charging batteries, specially adapted for electric vehicles; Charging stations or on-board charging equipment therefor; Exchange of energy storage elements in electric vehicles
  • B60L53/30—Constructional details of charging stations
  • B60L53/305—Communication interfaces
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L53/00—Methods of charging batteries, specially adapted for electric vehicles; Charging stations or on-board charging equipment therefor; Exchange of energy storage elements in electric vehicles
  • B60L53/60—Monitoring or controlling charging stations
  • B60L53/63—Monitoring or controlling charging stations in response to network capacity
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L53/00—Methods of charging batteries, specially adapted for electric vehicles; Charging stations or on-board charging equipment therefor; Exchange of energy storage elements in electric vehicles
  • B60L53/60—Monitoring or controlling charging stations
  • B60L53/67—Controlling two or more charging stations
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
  • B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
  • B60L58/12—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries responding to state of charge [SoC]
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
  • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
  • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
  • H02J7/0013—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries acting upon several batteries simultaneously or sequentially
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
  • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
  • H02J7/0029—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
  • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
  • H02J7/0047—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with monitoring or indicating devices or circuits
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/60—Other road transportation technologies with climate change mitigation effect
  • Y02T10/70—Energy storage systems for electromobility, e.g. batteries
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/60—Other road transportation technologies with climate change mitigation effect
  • Y02T10/7072—Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02T90/10—Technologies relating to charging of electric vehicles
  • Y02T90/12—Electric charging stations
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02T90/10—Technologies relating to charging of electric vehicles
  • Y02T90/14—Plug-in electric vehicles
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02T90/10—Technologies relating to charging of electric vehicles
  • Y02T90/16—Information or communication technologies improving the operation of electric vehicles
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
  • Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
  • Y04S10/00—Systems supporting electrical power generation, transmission or distribution
  • Y04S10/12—Monitoring or controlling equipment for energy generation units, e.g. distributed energy generation [DER] or load-side generation
  • Y04S10/126—Monitoring or controlling equipment for energy generation units, e.g. distributed energy generation [DER] or load-side generation the energy generation units being or involving electric vehicles [EV] or hybrid vehicles [HEV], i.e. power aggregation of EV or HEV, vehicle to grid arrangements [V2G]

Definitions

• the disclosed technology relates to battery charging systems and in particular to systems for charging multiple sets of batteries.
• the disclosed technology relates to a battery charging system that employs multiple channels to simultaneously charge multiple battery packs at independently controlled charge rates.
• a central controller intelligently instructs each channel to deliver a selectable amount of power to charge the batteries in the channel.
• the central controller instructs battery chargers associated with each of the channels to deliver all or nearly all of the charging power available from a source to charge the batteries.
• the system includes a power source that is rated to provide a maximum amount of charging power that is available to charge multiple batteries that are arranged in different channels.
• a number of battery chargers associated with the different channels are individually controllable to charge one or more batteries with a selectable amount of power.
• a central controller receives information from the batteries to be charged and directs the battery chargers in a channel to charge the batteries with a selectable amount of power.
• the central controller controls the power delivered by each of the battery chargers so that the total amount of power delivered is equal, or nearly equal, to the maximum amount of charging power that is available from the power source.
• FIG. 1 illustrates a battery charging system in accordance with an embodiment of the disclosed technology
• Figure 2 depicts a central controller and a single battery charger for a channel in accordance with an embodiment of the disclosed technology
• Figure 3 illustrates a rechargeable battery and a number of electrical connections to a battery charger for a channel in accordance with an embodiment of the disclosed technology
• Figure 4 shows a pair of diodes that connect an individual set of battery cells to power cables to improve safely in accordance with an embodiment of the disclosed technology.
• the disclosed technology relates to a battery charging system that can be used to charge a fleet of vehicles.
• the vehicles are electric boats that are powered by one or more rechargeable batteries.
• other vehicles or devices having rechargeable batteries could also be charged such as cars, motorcycles, lawn mowers or other equipment, drones and the like.
• FIG. 1 shows a representative environment where the charging system of the disclosed technology can be used.
• a fleet operator owns a number of electric boats B1 -B3 that are powered by rechargeable battery packs.
• a power source 50 typically includes an AC to DC converter that converts commercial AC power from the grid into a variable DC voltage. The DC voltage produced is often unregulated and fluctuates depending on the instantaneous load placed on the commercial grid.
• the power source 50 has a maximum power rating such as 1 .5 KW, 6 KW, 10 KW etc.
• the power source 50 supplies the power required to charge the batteries in each of the boats.
• the charging system of the disclosed technology uses a central controller 100 to variably control the amount of power to be used by a battery charger in each of a number of different channels. For example, the batteries of boats B2 and B3 may be nearly charged while the batteries of boat B1 may be mostly depleted. Therefore, the central controller 100 can direct a battery charger 1 10a associated with the boat B1 to use more of the capacity of the power source 50 than the power used by the battery
• chargers 1 10b and 1 10c to charge the batteries of boats B2 and B3 respectively.
• each of the battery chargers 1 10 for the different boats is controllable to use between 0-100% of the capacity of the power source 50 to charge its respective batteries.
• the power source 50 has a rating of 6 KW
• each of the battery chargers 1 10a-1 10c for the three channels can use between 0 and 6KW of charging power for its respective battery load.
• the total power used by the battery chargers in all the channels together cannot exceed the maximum power rating of the power source 50 and the battery charger for each channel should not charge its associated batteries at a rate that exceeds the charging capacity of the batteries.
• the battery charger 1 10a may be directed to use 4KW of charging power while the remaining 2KW of charging power is split evenly between the battery chargers for the other two channels.
• battery charger 1 10a may be controlled to use all 6KW of charging power and the battery chargers for the other two channels are turned off.
• the central controller 100 can therefore divide the power used by the battery charger in each channel as necessary.
• the central controller 100 controls the battery chargers in each of the channels so that the total power used is equal to (or nearly equal to) the maximum power rating of the power source 50.
• the central controller 100 is a microcontroller-based system that is programmable to control how much power is used by the battery chargers in each of the channels.
• the microcontroller is programmed to receive information from each of the battery packs to be charged and may be programmed to implement one of a number of different charging routines or schedules.
• the battery chargers of each channel may be controlled so that the battery packs of all the vehicles in the fleet are fully charged by a specific time.
• the microcontroller 100 may be programmed to control the battery charger in a channel so that the battery packs with the lowest voltage are charged with more power than the battery packs associated with other battery chargers. When all the battery packs achieve some nominal level of charge, the available power can be evenly divided between the battery chargers.
• the central controller 100 has an input mechanism 102 for changing a program that determines how the central controller divides the charging power between the battery chargers in each of the channels.
• Such an input mechanism 102 can include a keyboard or keypad and may include an associated display 104 that an operator can use to enter commands to change the programming of the central controller.
• the central controller includes one or more ports 106 (USB, Ethernet, serial ports, parallel ports or the like) that receives the programming commands for the microcontroller.
• the central controller includes a wireless communication chipset (WiFi, Bluetooth, cellular, satellite etc.) that allows the central controller to be programmed wirelessly from a remote computer 108.
• FIG. 2 illustrates further details of a battery charger 1 10 associated with a single channel and its connections to the central controller 100.
• the battery chargers associated with the other channels are constructed in the similar manner.
• each battery charger has the same maximum power that it can use to charge the battery packs in its channel. However, it is possible that some battery chargers may have a greater power capacity than others.
• the central controller 100 knows the maximum power capacity of the battery charger for each channel.
• the battery charger 1 10 includes a pulse width modulation (PWM) battery charging circuit 150 than can operate in either a constant current (CC) or constant voltage (CV) mode under the direction of a signal sent from the central controller 100.
• PWM pulse width modulation
• An enable line from the central controller 100 to the PWM battery charging circuit 150 allows the central controller to turn on and turn off the battery charging circuit.
• a 12 volt power source 154 is provided to supply power to circuitry, such as the battery management system, in the battery packs to be charged.
• Signal conditioning circuits 156 and 158 condition and provide isolation for communication signals and an interlock signal transmitted to and from the battery packs being charged as will be described below.
• the battery charger 1 10 also includes feedback circuitry 160 that monitors an output charging voltage and an output current produced by the PWM battery charging circuit 150. Signals representative of the output voltage and current are fed back to inputs (such as A/D converters) on the central controller 100. By multiplying the output voltage and the output current from the PWM battery charging circuit 150, the central controller 100 estimates the power being delivered by the battery charger 1 10.
• the central controller 100 sends one or more PWM signals having a duty cycle that is proportional to the power that should be used by the battery charger 1 10.
• a pulse with a duty cycle of 50% of the maximum duty cycle for a pulse is interpreted to mean that the battery charger is to operate at 50% of its maximum power rating etc.
• Other methods of signaling the battery charger 1 10 could also be used, such as by providing an analog voltage or current or by providing a digital signal (e.g. 0-255) etc.
• the PWM battery charging circuit 150 can be programmed to deliver a specific charging current while letting the voltage required to produce such a current vary. Alternatively, the battery charging circuit 150 can be programmed to deliver a specific voltage regardless of the current required to produce such a voltage. Most modern rechargeable batteries are charged by supplying a constant current specified by the manufacturer. The optimal rate can be reported by a battery management system to the central controller 100 as explained below. Once the battery pack reaches a particular voltage value, some battery chemistries require the batteries to be charged with a constant voltage (and variable current) until the battery pack is fully charged. Other charging schemes are also possible depending the type of batteries to be charged and the programming of the central controller 100.
• the central controller 100 supplies a variable value signal to the PWM battery charging circuit 150 representing a value between 0 and 100% of the power of the power source 50 to be used in charging the batteries for that channel.
• the number may represent between 0-100% of the total power that can be delivered by the PWM battery charger 150 (which may be different than the total power available from the power source). For example, if the PWM battery charging circuit 150 can deliver at most 4KW of charging power, then a value of 50% may represent 2KW and a value of 100% may represent 4KW even if the total power available from the power source is 6KW.
• a battery management system associated with each battery pack to be charged reports the voltage of the battery pack to the central controller 100 over a communication link (e.g. CAN communication link).
• the central controller 100 determines if the battery pack should be charged with a constant current or a constant voltage. Assuming that a constant current is used, a current is selected so that the power used by the battery charger is less than or equal to the maximum power that should be used by the battery charger and that is within the safe charging range for the batteries to be charged.
• a voltage is selected so that that the power used by the battery charger is less than or equal to the maximum power that should be used by the battery charger 1 10 and that is within the safe charging range for the batteries to be charged.
• FIG. 3 shows some of the internal components of a battery pack 300 to be charged with the charging system in accordance with an embodiment of the disclosed technology.
• the configuration of batteries in a battery pack may vary but in one embodiment, each battery pack 300 includes six serially connected modules of 80 rechargeable battery cells 310 for a total of 480 battery cells per battery pack.
• a vehicle such as an electric boat may include several battery packs that are connected in parallel to provide sufficient current to drive the vehicle.
• the battery pack 300 has an input port I and an output port O. These names are assigned as a convenience as the ports are functionally equivalent.
• the input port I receives a cable connector with wires connected to a vehicle charging receptacle and to power bus cables that the vehicle uses to draw power during operation.
• Internal connections are provided within the battery pack between the input port I and the output port O to put some of the contacts in the input port in parallel with contacts in the output port so that multiple batteries can be daisy chained together (e.g. by connecting a cable from an input port of one battery pack to an output port of another battery pack).
• a battery management system 320 in the battery pack is provided to monitor and report one or more battery conditions such as, but not limited to, the internal temperature of the batteries, the charge or discharge current from the battery cells 310, the voltage of the battery cells, the number of times the battery pack has been recharged, the charge/discharge rate C for arrangement of battery cells 310.
• the battery management system 320 controls the position of a number of switches S1 and S2 that connect the positive and negative terminals of the arrangement of battery cells 310 to the power cables in the vehicle. If the battery management system detects that the batteries are overheating, that the output current current is too high or there is some other anomaly occurring in the batteries, then the battery management system can independently operate to open the switches S1 and S2 and disconnect the battery pack from the power cables.
• the battery management system communicates information to and from the central controller 100 using a communication bus such as a set of CAN (controller area network) lines of the type commonly used in electric vehicles.
• a communication bus such as a set of CAN (controller area network) lines of the type commonly used in electric vehicles.
• Internal connections within the battery pack 300 put the connectors for the CAN lines in parallel between the input port I and the output port O so that the CAN lines for each daisy chained battery in a vehicle are in parallel.
• each battery pack can be equipped with a wireless communication chip set to communicate signals wirelessly.
• a 12 volt line and a ground line are connected to the input port I to supply power the battery management system 320.
• the battery management system 320 reports information to the central controller including information about its set of battery cells 310.
• Such battery information can include the serial number of the battery pack, the number of charging cycles applied to the battery pack, maximum charging current and voltage for the batteries in the battery pack, etc.
• the battery management system 320 selectively connects the 12 volt line to a connector on the output port using a switch S3. When battery management system is instructed to close the switch S3 to power a next battery that is daisy chained to the output port O.
• the battery management system of that battery pack reports its information on the CAN leads and so on, until the last battery pack in the vehicle is reached. In this way, the central controller knows how many battery packs are in a vehicle and what the state of charge is for each set of batteries in each battery pack.
• the battery pack 300 is connected to an interlock line that is run serially from the input port to the output port. The interlock line returns back from the last connected battery pack to the central controller 100 through the signal conditioning circuit 158 in the battery charger 1 10 to form a continuous electrical path through each of the battery packs to be charged. If the interlock line is broken by disconnecting one of the battery packs from the circuit, the central controller will be alerted and can take appropriate action such as disabling its output.
• each of the sets of battery cells 310 is connected to the power cables via a pair of switches S1 and S2.
• the switches are controlled by the battery management system 320.
• the battery management system can disconnect the battery cells from the power cables if it detects a fault in the battery or an unsafe condition occurs.
• the battery management system can connect the battery cells to the power cables by closing the switches S1 and S2 upon instructions from the central controller.
• the battery cells of different battery packs in a vehicle may be at different voltages when they are to be recharged.
• the central controller 100 instructs a battery management system 320 to connect the batteries in the battery pack with the lowest voltage to the power cables so that the lowest charged battery pack is charged first. Once the voltage of that battery pack rises to the voltage of the batteries in another battery pack, then those batteries are connected to the power cables to charge. This process can continue until all the sets of battery cells are connected in parallel to the battery charger for that channel.
• the batteries may be charged with a constant current or a constant voltage.
• the central controller 100 may direct the PWM charging circuit to adjust the current or voltage depending on the number of battery packs to be charged, the maximum current or voltage that can be delivered to the connected battery packs and the total power being delivered by the charging circuit.
• the central controller 100 reads the voltage and current produced by the PWM charging circuit 150 to know how much power is being delivered by the battery charger. The central controller then can adjust the amount of power to be used by the battery charger for a particular channel so the total power is less than or equal to the total amount of charging power available from the power source and so that the charging power delivered is within the safe operating range of the batteries in the channel.
• the central controller 100 commands each of the battery chargers in each of the channels to use an amount of power such that that the total amount of power used is equal to (or nearly equal to) the maximum power that can be provided by the power source 50.
• the central controller 100 therefore can independently control the power delivered by the battery charger of each channel.
• the voltage and current outputs of the PWM battery charging circuit 150 are used to determine when to switch from a constant current charging mode to a constant voltage charging mode.
• the battery management system 320 of each battery pack periodically reports the voltage of its batteries and those values are used by the central controller to determine how to charge the batteries.
• FIG. 4 illustrates an additional feature that can be added to each set of battery cells. The addition of two diodes on the positive terminal of the battery cells, along with a single pole double throw (SPDT) switch can be used to prevent current flow between battery cells at different voltages.
• SPDT single pole double throw
• the SPDT switch is connected to Diode 2, which allows current to flow out of the set of battery cells when the voltage of the battery cells is greater than the voltage at the high side terminal, but prevents current flow in the opposite direction when the voltage at the high side terminal is greater than the voltage of the set of battery cells.
• Diode 1 allows current to flow into the set of battery cells when the voltage at the high side terminal is greater than the voltage of the set of battery cells, but prevents current flow in the opposite direction when the voltage of the set of battery cells is greater than the voltage at the high side terminal.
• An additional safety feature is that the default switch location is connected to Diode 1 (i.e., when the battery pack is not in use), which ensures that no current can flow from the battery cell terminals.
• Diode 1 i.e., when the battery pack is not in use
• This is a redundant safety feature since there is typically another switch (Low Side Contactor in Figure 4) whose default position is OPEN, also preventing current flow from the battery cell terminals when not in use.
• each charging channel requires communication between the batteries and the central controller, and certain conditions must be satisfied before charging will be initiated. Once all conditions have been satisfied, the central controller sends a request to the battery pack to close an internal electrically controlled switch (contactor), which establishes an electrically conductive path between the energy storage devices (e.g. cells) within the battery pack and the external connectors. Likewise, the charging system closes its own internal electrically controlled switch to enable power to the external connectors.
• contactor an internal electrically controlled switch

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• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Life Sciences & Earth Sciences (AREA)
• Sustainable Development (AREA)
• Sustainable Energy (AREA)
• Charge And Discharge Circuits For Batteries Or The Like (AREA)
• Secondary Cells (AREA)

Applications Claiming Priority (1)

Publications (2)

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• 2017
  • 2017-04-10 CN CN201780091893.7A patent/CN110870157A/zh active Pending
  • 2017-04-10 EP EP17905750.0A patent/EP3602730A4/de active Pending
  • 2017-04-10 WO PCT/US2017/026852 patent/WO2018190796A1/en unknown

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