Apparatus and method for charging and discharging a dual battery system

• US 10,017,057 B2
• Filed: 12/17/2015
• Issued: 07/10/2018
• Est. Priority Date: 10/19/2011
• Status: Active Grant

• Current Assignee: Larry Nelson
• Original Assignee: Larry Nelson
• Inventors: Nelson, Larry
• Primary Examiner(s): Chang, Joseph
• Application Number:
  US14/973,143
• Publication Number:
  US 20160176303A1
• Time in Patent Office: 936 Days
• Field of Search: 307 101
• CPC Class Codes: B60L 2250/16 by display
• CPC Class Codes: B60L 50/52 characterised by DC-motors
• CPC Class Codes: B60L 53/14 Conductive energy transfer
• CPC Class Codes: B60L 58/13 Maintaining the SoC within a determined range
• CPC Class Codes: B60L 58/19 Switching between serial connection and parallel connection of battery modules
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: B60W 10/00 Conjoint control of vehicle sub-units of different type or different function for propulsion of purely electrically-propelled vehicles with power supplied within the vehicle B60L50/00 - B60L58/00
• CPC Class Codes: H02J 7/0024 Parallel/serial switching of connection of batteries to charge or load circuit
• CPC Class Codes: H02J 7/00304 Overcurrent protection
• CPC Class Codes: H02J 7/00308 Overvoltage protection
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: H02J 7/0049 Detection of fully charged condition
• CPC Class Codes: H02J 7/1423 with multiple batteries
• CPC Class Codes: H02K 53/00 Alleged dynamo-electric perpetua mobilia
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A dual battery charging and discharging system controls the configuration of multiple batteries arranged in multiple battery banks. The batteries within each bank are connected in series when powering an electrical load, such as a service motor, and are connected in parallel when charging. A microprocessor monitors the voltage levels of the batteries in each bank and controls relays to switch the electrical load over to a charged battery bank when the voltage level of the discharging battery bank drops below a minimum run threshold. The microprocessor also monitors the voltage levels of the charging battery bank and controls relays to cease charging when the voltage level rises above a minimum charge threshold. The batteries are charged by an alternator driven by a drive motor through a gear reduction system.

Claims

1. An apparatus for charging and discharging batteries comprising:

a first battery bank comprising at least a first battery and a second battery;

a second battery bank comprising at least a third battery and a fourth battery;

a first voltage sensing node for monitoring voltage of the first battery;

a second voltage sensing node for monitoring voltage of the second battery;

a third voltage sensing node for monitoring voltage of the third battery;

a fourth voltage sensing node for monitoring voltage of the fourth battery;

a service motor for driving a load, wherein the service motor is operable to receive power from one or more of the first battery bank and the second battery bank;

an alternator operable to provide a charging voltage to one or more of the first battery bank and the second battery bank;

a drive motor operable to drive the alternator to cause generation of the charging voltage, wherein the drive motor is operable to receive power from one or more of the first battery bank and the second battery bank;

one or more first switches operable to selectively connect or disconnect the first battery bank to or from the service motor, thereby providing power to or removing power from the service motor;

one or more second switches operable to selectively connect or disconnect the second battery bank to or from the service motor, thereby providing power to or removing power from the service motor;

one or more third switches operable to selectively connect or disconnect the first battery bank or the second battery bank to or from the drive motor, thereby providing power to or removing power from the drive motor;

one or more fourth switches operable to selectively connect the first battery bank to the alternator to receive the charging voltage and operable to selectively disconnect the second battery bank from the alternator; and

the one or more fourth switches operable to selectively connect the second battery bank to the alternator to receive the charging voltage and operable to selectively disconnect the first battery bank from the alternator; and

a microcontroller operable to monitor voltages on the first, second, third and fourth voltage sensing nodes, and to control one or more of the first, second, third and fourth switches based at least in part on the voltages monitored.

2. The apparatus of claim 1 wherein:

the one or more first switches are operable to connect the first and second batteries of the first battery bank in series when providing power to one or more of the service motor and the drive motor;

the one or more second switches are operable to connect the third and fourth batteries of the second battery bank in series when providing power to one or more of the service motor and the drive motor;

the one or more fourth switches are operable to connect the first and second batteries of the first battery bank in parallel when receiving the charging voltage from the alternator; and

the one or more fourth switches are operable to connect the third and fourth batteries of the second battery bank in parallel when receiving the charging voltage from the alternator.

3. The apparatus of claim 1 wherein one or more of the first, second, third and fourth switches comprise relays.

4. The apparatus of claim 1 further comprising a drive train mechanically coupled between the drive motor and the alternator, the drive train operable to increase a turning speed of the alternator relative to a turning speed of the drive motor.

5. The apparatus of claim 4 wherein the drive train is operable to increase the turning speed of the alternator relative to the turning speed of the drive motor by at least a factor of six.

6. The apparatus of claim 4 wherein the drive train comprises one or more belts and pulleys.

7. The apparatus of claim 1 operable in a first mode wherein:

the one or more first switches are configured to connect the first battery bank to provide power to the service motor;

the one or more second switches are configured to disconnect the second battery bank from the service motor;

the one or more third switches are configured to connect the first battery bank to provide power to the drive motor;

the one or more fourth switches are configured to connect the second battery bank to the alternator to receive the charging voltage; and

the one or more fourth switches are configured to disconnect the first battery bank from the alternator.

8. The apparatus of claim 1 operable in a second mode wherein:

the one or more first switches are configured to disconnect the first battery bank from the service motor;

the one or more second switches are configured to connect the second battery bank to provide power to the service motor;

the one or more third switches are configured to connect the second battery bank to provide power to the drive motor;

the one or more fourth switches are configured to connect the first battery bank to the alternator to receive the charging voltage; and

the one or more fourth switches are configured to disconnect the second battery bank from the alternator.

9. The apparatus of claim 1 wherein:

the first and second batteries comprise 12 volt batteries;

the third and fourth batteries comprise 12 volt batteries;

the service motor comprises a 24 volt motor;

the alternator provides a charging voltage of 12 volts; and

the drive motor comprises a 24 volt motor.

10. A method for charging and discharging a first battery bank comprising at least a first battery and a second battery and a second battery bank comprising at least a third battery and a fourth battery, wherein the first and second battery banks selectively provide power to a service motor that drives a load and to a drive motor that drives a voltage source to cause generation of a charging voltage, wherein the first and second battery banks selectively receive the charging voltage from the voltage source, the method comprising:

(a) connecting the first battery bank to the service motor to provide power to the service motor;

(b) monitoring a voltage of one or more of the first and second batteries of the first battery bank;

(c) after the voltage of one or more of the first and second batteries of the first battery bank drops to or below a first threshold voltage, operating one or more of a plurality of switches to

(c1) disconnecting one or more of the first and second batteries of the first battery bank from the service motor,

(c2) connect one or more of the third and fourth batteries of the second battery bank to the service motor and the drive motor to provide power to the service motor and the drive motor,

(c3) connect one or more of the first and second batteries of the first battery bank to the voltage source to receive the charging voltage, and

(c4) charge one or more of the first and second batteries of the first battery bank,

(d) after the voltage of one or more of the first and second batteries of the first battery bank reaches or rises above a second threshold voltage, operating one or more of the plurality of switches to disconnect one or more of the first and second batteries of the first battery bank from the voltage source;

(e) monitoring a voltage of one or more of the third and fourth batteries of the second battery bank;

(f) after the voltage of one or more of the third and fourth batteries of the second battery bank drops to or below the first threshold voltage, operating one or more of the plurality of switches to

(f1) disconnect one or more of the third and fourth batteries of the second battery bank from the service motor,

(f2) connect one or more of the first and second batteries of the first battery bank to the service motor and the drive motor to provide power to the service motor and drive motor,

(f3) connect one or more of the third and fourth batteries of the second battery bank to the voltage source to receive the charging voltage; and

(f4) charge one or more of the third and fourth batteries of the second battery bank, and

(g) after the voltage of one or more of the third and fourth batteries of the second battery bank rises to or above the second threshold voltage, operating one or more of the plurality of switches to disconnect one or more of the third and fourth batteries of the second battery bank from the voltage source.

11. The method of claim 10 wherein step (c3) further comprises operating one or more of the plurality of switches to connect the first and second batteries of the first battery bank in parallel, and step (f3) further comprises operating one or more of the plurality of switches to connect the third and fourth batteries of the second battery bank in parallel.

12. The method of claim 10 wherein steps (a) and (f2) further comprise operating one or more of the plurality of switches to connect the first and second batteries of the first battery bank in series, and step (c2) further comprises operating one or more of the plurality of switches to connect the first and second batteries of the second battery bank in series.

13. The method of claim 10 wherein the voltage source is an alternator.

14. An apparatus for charging and discharging batteries comprising:

a first battery bank comprising at least a first battery and a second battery;

a second battery bank comprising at least a third battery and a fourth battery;

a service motor for driving a load, wherein the service motor is operable to receive power from one or more of the first battery bank and the second battery bank;

a voltage source operable to provide a charging voltage to one or more of the first battery bank and the second battery bank;

a drive motor operable to drive the voltage source to cause generation of the charging voltage, wherein the drive motor is operable to receive power from one or more of the first battery bank and the second battery bank;

a drive train mechanically coupled between the drive motor and the voltage source, the drive train operable to increase a turning speed of the voltage source relative to a turning speed of the drive motor;

one or more switches operable to

selectively connect or disconnect the first battery bank or the second battery bank to or from the service motor to provide power to or remove power from the service motor,

selectively connect or disconnect the first battery bank or the second battery bank to or from the drive motor to provide power to or remove power from the drive motor,

selectively connect the first battery bank to the voltage source to receive the charging voltage and selectively disconnect the second battery bank from the voltage source, and

selectively connect the second battery bank to the voltage source to receive the charging voltage and selectively disconnect the first battery bank from the voltage source; and

a microcontroller operable to monitor voltages of the first, second, third, and fourth batteries, and control the one or more switches based at least in part on the voltages monitored.

15. The apparatus of claim 14 wherein the drive train is operable to increase the turning speed of the voltage source relative to the turning speed of the drive motor by at least a factor of six.

16. An apparatus for charging and discharging batteries while providing power to an electrical load, the apparatus comprising:

a first battery bank comprising at least a first battery and a second battery;

a second battery bank comprising at least a third battery and a fourth battery;

a voltage source operable to provide a charging voltage to one or more of the first battery bank and the second battery bank;

a drive motor operable to drive the voltage source to cause generation of the charging voltage, wherein the drive motor is operable to receive power from one or more of the first battery bank and the second battery bank;

one or more first switches operable to selectively connect or disconnect the first battery bank to or from the electrical load, thereby providing power to or removing power from the electrical load;

one or more second switches operable to selectively connect or disconnect the second battery bank to or from the electrical load, thereby providing power to or removing power from the electrical load;

one or more third switches operable to selectively connect or disconnect the first battery bank or the second battery bank to or from the drive motor, thereby providing power to or removing power from the drive motor;

one or more fourth switches operable to selectively connect the first battery bank to the voltage source to receive the charging voltage and operable to selectively disconnect the second battery bank from the voltage source;

the one or more fourth switches operable to selectively connect the second battery bank to the voltage source to receive the charging voltage and operable to selectively disconnect the first battery bank from the voltage source; and

a microcontroller operable to monitor voltages of the first, second, third, and fourth batteries, and control one or more of the first, second, third, and fourth switches based at least in part on the voltages monitored.

17. The apparatus of claim 16 wherein the electrical load is selected from the group consisting of an electric motor driving a transmission of an electric vehicle, an electric motor driving a propeller, electrical lighting, electronic components, and electrical appliances.