APPARATUS FOR PREHEATING A BATTERY PACK BEFORE CHARGING

• US 20110248684A1
• Filed: 04/07/2011
• Published: 10/13/2011
• Est. Priority Date: 04/08/2010
• Status: Active Grant

• Current Assignee: Sinoelectric Powertrain Corporation
• Original Assignee: Sinoelectric Powertrain Corporation
• Inventors: Zhou, Peng
• Granted Patent: US 8,779,728 B2
• Time in Patent Office: Days
• US Class Current: 320/150
• CPC Class Codes: B60L 53/00 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
• CPC Class Codes: B60L 58/27 by heating
• 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 system for charging a battery pack of an electric vehicle comprises a heater for pre-heating the battery pack so that the battery pack is able to accept a charge from a charger. The battery pack is selectively de-coupled from the system during the pre-heating. When the battery pack has reached an appropriate temperature, the heater is selectively de-coupled from the system and the charger is coupled to the system to charge the battery. Advantageously, the battery pack is protected during pre-heating.

Claims

1. A system for charging a battery in an electric vehicle comprising:

a. a battery, the battery having a master switch coupled to a second terminal of the battery;

b. a heater for heating a battery during a pre-charging phase;

c. an on board charger coupled to a first terminal of the battery through a first switch;

d. an off board charger coupled to the first terminal of the battery through a second switch;

e. a DC to DC converter coupled to the heater and to the first terminal of the battery through a third switch, wherein the DC to DC converter is also coupled to the on board charger through the third switch and first switch and to the off board charger through the third switch and second switch;

f. a temperature sensor for sensing a temperature of the battery; and

g. a controller for receiving the temperature of the battery, wherein the controller is coupled to the master switch, first switch, second switch, and third switch, wherein during a pre-charging phase, the controller opens the master switch, closes the third switch and one of the first switch and second switch thereby electrically isolating the battery while coupling the DC to DC converter to one of the on board charger and off board charger for providing power to the heater, and wherein in a charging phase, the controller closes the master switch, opens the third switch, and closes one of the first switch and second switch, thereby forming an electrical path from one of the on board charger and off board charger to the battery.

2. The system of claim 1 wherein the controller switches from a pre-charging stage to a charging stage when the battery reaches a pre-defined temperature.

3. The system of claim 1 wherein the controller switches from a pre-charging stage to a charging stage when the battery reaches a user configured temperature.

4. A method of charging a battery comprising:

a. defining a pre-charging stage;

b. defining a charging stage;

c. coupling one of an on board charger and an off board charger to a DC to DC converter, wherein the DC to DC converter supplies power to a heater while electrically isolating the battery from the on board charger, off board charger and DC to DC converter, during a pre-charging stage; and

d. coupling one of the on board charger and the off board charger to the battery while electrically isolating the DC to DC converter from the battery during a charging stage.

5. The method of claim 4 wherein defining a pre-charging stage comprises determining a minimum temperature at which the battery accepts charge.

6. The method of claim 4 wherein defining a charging stage comprises determining a minimum temperature at which the battery accepts charge.

7. The method of claim 4 wherein coupling the battery to a charging means for charging the battery when the battery has reached a desired temperature comprises programming a controller to selectively couple the charging means to one of the battery and a heater.