Method of calculating SOC of battery for prevention of memory effect

• US 20060132094A1
• Filed: 12/08/2005
• Published: 06/22/2006
• Est. Priority Date: 12/21/2004
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: Koo, Jae-Seung
• Granted Patent: US 7,345,452 B2
• Time in Patent Office: Days
• US Class Current: 320/132
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 58/13 Maintaining the SoC within a determined range
• CPC Class Codes: G01R 31/007 using microprocessors or computers
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/3832 without measurement of battery voltage
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

Disclosed herein is a method of calculating the SOC of a battery. The method includes the steps of receiving information about a previous SOC mode and operation time in the mode from memory of a battery controller after startup of the vehicle; calculating a battery SOC data value using one of respective different reference capacities depending on whether a normal SOC preservation mode, a high SOC range expansion mode, or a low SOC range expansion mode using the battery controller and transmitting the battery SOC data value to a vehicle controller; and determining whether conditions for entering a next SOC mode is met after calculation of an actual SOC value of the battery in the normal SOC preservation mode, the high SOC range expansion mode, or the low SOC range expansion mode.

Claims

1. A method of calculating an SOC(State Of Charge) of a battery of a hybrid vehicle, comprising the steps of:

receiving information about a previous SOC mode and operation time in the mode from memory of a battery controller after startup of the vehicle;

calculating a battery SOC data value using one of respective different reference capacities depending on whether a normal SOC preservation mode, a high SOC range expansion mode, or a low SOC range expansion mode using the battery controller and transmitting the battery SOC data value to a vehicle controller; and

determining whether conditions for entering a next SOC mode is met after calculation of an actual SOC value of the battery in the normal SOC preservation mode, the high SOC range expansion mode, or the low SOC range expansion mode.

2. The method as defined in claim 1, wherein the calculation of the SOC data value (HCU_SOC) is performing by calculating the SOC data value (HCU_SOC), which will be to be transmitted to the vehicle controller, using the battery reference capacity in the normal SOC preservation mode, calculating the SOC data value using a value larger than the reference capacity (Ah_basic) at a time of charging and using a value smaller than Ah_basic at a time of discharge in the high SOC expansion mode, and calculating the SOC data value using a value smaller than the reference capacity (Ah_basic) at the time of charging and using a value larger than the reference capacity (Ah_basic) at the time of discharge in the low SOC expansion mode.

3. The method as defined in claim 1, wherein the entry to a specific mode is performed by entering the low SOC range expansion mode if a mode operation time exceeds a predetermined time in the normal SOC preservation mode, entering the high SOC range expansion mode if the SOC data value is larger than a predetermined value of the low SOC range expansion mode in the low SOC range expansion mode, and entering the normal SOC preservation mode if the SOC data value is larger than a predetermined value of the high SOC range expansion mode in the high SOC range expansion mode, and then determining whether the conditions for entering the next SOC mode, in which the SOC value of the battery is calculated using a corresponding reference capacity in the corresponding SOC mode, is met.