BATTERY CHARGING SYSTEM AND CHARGING METHOD USING SAME

• US 20130264995A1
• Filed: 06/05/2013
• Published: 10/10/2013
• Est. Priority Date: 09/23/2011
• Status: Active Grant

• Current Assignee: LG Energy Solution Limited (LG Corporation)
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: LEE, Sun Jong
• Granted Patent: US 9,937,805 B2
• Time in Patent Office: Days
• US Class Current: 320/104
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2250/16 by display
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 53/11 DC charging controlled by the charging station, e.g. mode 4
• CPC Class Codes: B60L 53/14 Conductive energy transfer
• CPC Class Codes: B60L 53/65 involving identification of vehicles or their battery types
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H02J 2310/48 for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 7/342 The other DC source being a battery actively interacting with the first one, i.e. battery to battery charging with circuits for polarity protection H02J7/0034
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• 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 10/72 Electric energy management in electromobility
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles
• CPC Class Codes: Y02T 90/167 Systems integrating technologies related to power network operation and communication or information technologies for supporting the interoperability of electric or hybrid vehicles, i.e. smartgrids as interface for battery charging of electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: Y04S 30/14 : Details associated with the interoperability, e.g. vehicle recognition, authentication, identification or billing

Abstract

Disclosed are a battery charging system and method. The battery charging system according to the present invention includes a first connector connected to both ends of a battery of a charging providing car; a second connector connected to both ends of a battery of a charging target car; a converter configured to convert a voltage transmitted from the battery of the charging providing car through the first connector and transmit the converted voltage to the battery of the charging target car through the second connector; and a controller connected to each of a battery management system (BMS) of the charging providing car and a BMS of the charging target car to control a voltage conversion ratio of the converter based on a state information on each of the batteries transmitted from each of the BMSs.

Claims

1. A battery charging system comprising:

a first connector connected to both ends of a battery of a charging providing car;

a second connector connected to both ends of a battery of a charging target car;

a converter connected between the first connector and the second connector and configured to convert a voltage transmitted from the battery of the charging providing car through the first connector and transmit the converted voltage to the battery of the charging target car through the second connector; and

a controller configured to control an electrical connection of the first connector and the second connector and connected to each of a battery management system (BMS) of the charging providing car and a BMS of the charging target car to control a voltage conversion ratio of the converter based on a state information on each of the batteries transmitted from each of the BMSs.

2. The battery charging system according to claim 1, wherein the first connector comprises:

a first positive electrode relay configured to connect a positive electrode of the battery of the charging providing car and a positive electrode of an input terminal of the converter;

a first negative electrode relay configured to connect a negative electrode of the battery of the charging providing car and a negative electrode of the input terminal of the converter;

a first capacitive element connected to the input terminal of the converter in parallel; and

a first precharge unit connected to the first positive electrode relay in parallel,

wherein the first precharge unit comprises a first precharge relay and a first precharge resistor connected to the first precharge relay in series.

3. The battery charging system according to claim 2, wherein the controller performs an input side precharge of charging a predetermined voltage in the first capacitive element by opening the first positive electrode relay to disconnect a connection and closing the first negative electrode relay and the first precharge relay when the first connector is connected to the battery of the charging providing car, and performs power transmission to the converter from the battery of the charging providing car by closing the first positive electrode relay and opening the first precharge relay when the input side precharge is completed.

4. The battery charging system according to claim 1, wherein the second connector comprises:

a second positive electrode relay configured to connect a positive electrode of the battery of the charging target car and a positive electrode of an output terminal of the converter;

a second negative electrode relay configured to connect a negative electrode of the battery of the charging target car and a negative electrode of the output terminal of the converter;

a second capacitive element connected to the output terminal of the converter in parallel; and

a second precharge unit connected to one of the second positive electrode relay and the second negative electrode relay in parallel,

wherein the second precharge unit comprises a second precharge relay and a second precharge resistor connected to the second precharge relay in series.

5. The battery charging system according to claim 4, wherein the controller performs an output side precharge of charging a predetermined voltage in the second capacitive element by opening the second positive eletrode relay to disconnect a connection and closing the second negative electrode relay and the second precharge relay when the second connector is connected to the battery of the charging target car, and performs power transmission to the battery of the charging target car from the converter by closing the second positive electrode relay and opening the second precharge relay when the output side precharge is completed.

6. The battery charging system according to claim 1, wherein the state information on the battery of the charging providing car transmitted from the BMS of the charging providing car contains at least one of energy transmittable from the BMS of the charging providing car, a maximum instantaneous output power allowance, an output voltage of the battery of the charging providing car, and a power quantity transmitted from the battery of the charging providing car.

7. The battery charging system according to claim 1, wherein the state information on the battery of the charging target car transmitted from the BMS of the charging target car contains at least one of energy receivable from the BMS of the charging target car, a maximum instantaneous input power allowance, an input voltage of the battery of the charging target car, and a power quantity transmitted to the battery of the charging target car.

8. The battery charging system according to claim 1, further comprising:

a power meter connected to the converter and configured to measure a transmitted power quantity provided to the battery of the charging target car from the battery of the charging providing car.

9. The battery charging system according to claim 8, wherein the controller receives the transmitted power quantity from the power meter and calculates a rate based on the transmitted power quantity.

10. The battery charging system according to claim 9, further comprising:

a display unit connected to the controller,

wherein the display unit displays the transmitted power quantity and/or information on the rate.

11. (canceled)

12. A battery charging method comprising:

receiving battery state information on a battery of a charging providing car and a battery of a charging target car from a BMS of the charging providing car and a BMS of the charging target car, respectively;

performing an input side precharge by connecting a first precharge relay provided between the battery of the charging providing car and an input terminal of the converter with a first precharge resistor;

performing an output side precharge by connecting a second precharge relay provided between the battery of the charging target car and an output terminal of the converter with a second precharge resistor;

after the input side precharge ends, transmitting power to the input terminal of the converter from the battery of the charging providing car by disconnecting a connection of the first precharge relay and closing a first positive electrode relay configured to connect the battery of the charging providing car and the input terminal of the converter;

after the output side precharge ends, transmitting power to the battery of the charging target car from the output terminal of the converter by disconnecting a connection of the second precharge relay and closing a second positive electrode relay configured to connect the battery of the charging target car and the output terminal of the converter; and

controlling a voltage conversion ratio of the converter based on the battery state information and charging the battery of the charging target car, by a controller.

13. The battery charging method according to claim 12, wherein the battery state information received from the BMS of the charging providing car by the controller contains information on at least one of energy transmittable from the BMS of the chargig providing car, a maximum instantaneous output power allowance, an output voltage of the battery of the charging providing car, and a power quantity transmitted from the battery of the charging providing car.

14. The battery charging method according to claim 12, wherein the battery state information received from the BMS of the charging target car by the controller contains information on at least one of receivable energy, a maximum instantaneous input power allowance, an output voltage of the battery of the charging target car, and a power quantity transmitted to the battery of the charging target car.

15. The battery charging method according to claim 12, further comprising:

measuring a transmitted power quantity provided to the battery of the charging target car through the converter.

16. The battery charging method according to claim 15, further comprising:

calculating a power rate based on the transmitted power quantity.

17. The battery charging method according to claim 16, further comprising:

displaying information on the transmitted power quantity and/or the power rate.

18. The battery charging method according to claim 17, further comprising:

receiving the transmitted power quantity and/or the power rate before charging is initiated in order to select the transmitted power quantity and/or the power rate in advance.

19. The battery charging method according to claim 12, further comprising:

disconnecting a connection of the first precharge relay, the second precharge relay, a first main relay and a second main relay when a charging for the battery of the charging target car is completed.

20. The battery charging method according to claim 12, further comprising:

making a request for stopping power transmission/reception to the BMS of the charging providing car and the BMS of the charging target car when a charging for the battery of the charging target car is completed.

21. The battery charging method according to claim 12, further comprising:

making a request for electrically separating the battery of the charging target car from the inverter and a request for electrically separating the battery of the charging providing car from the inverter.