Method of estimating maximum output of battery for hybrid electric vehicle

• US 7,518,375 B2
• Filed: 03/06/2006
• Issued: 04/14/2009
• Est. Priority Date: 03/04/2005
• Status: Active Grant

• Current Assignee: LG Energy Solution Limited (LG Corporation)
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: Jung, Do Yang, Kim, Do Youn
• Primary Examiner(s): Ullah; Akm E
• Assistant Examiner(s): Tran; Nguyen
• Application Number:
  US11/368,896
• Publication Number:
  US 20060206276A1
• Time in Patent Office: 1,135 Days
• Field of Search: 324/427, 324/431
• US Class Current: 324/430
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 2240/662 Temperature
• CPC Class Codes: B60L 2260/44 by parameter estimation
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 58/14 Preventing excessive discharging
• CPC Class Codes: B60L 58/15 Preventing overcharging
• CPC Class Codes: G01R 31/006 on road vehicles, e.g. automobiles or trucks testing of ignition installations peculiar to internal combustion engines F02P17/00
• CPC Class Codes: G01R 31/3832 without measurement of battery voltage
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H02J 7/00302 Overcharge protection
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: H02J 7/14 for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle
• 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 10/72 Electric energy management in electromobility
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

Disclosed is a method of estimating a maximum output of a battery for a hybrid electric vehicle (HEV). The method comprises extracting maximum charge/discharge outputs of the battery depending on a plurality of charged states (SOC) of the battery under which the vehicle is able to be driven and calculating an interrelation between them; extracting maximum charge/discharge outputs of the battery at plural temperatures under which the vehicle is able to be driven, and calculating an interrelation between them; extracting degradations of outputs of the battery as a capacity of the battery is discharged during the traveling, and calculating an interrelation between them; and based on the interrelations obtained, estimating a maximum output of the battery using a function.

Claims

1. A method of estimating a maximum output of a battery for a hybrid electric vehicle comprising steps of:

extracting maximum charge or discharge outputs of the battery depending on a plurality of charged states (SOC) of the battery under which the vehicle is able to be driven and calculating an interrelation between them;

extracting maximum charge or discharge outputs of the battery at plural temperatures (temp) under which the vehicle is able to be driven, and calculating an interrelation between them;

extracting degradations of outputs of the battery as a capacity of the battery is discharged (accumulated discharge Ah) during traveling, and calculating an interrelation between them; and

based on the interrelations obtained from each of the steps, estimating a maximum output (Power_max) of the battery through a following function;

2. The method according to claim 1, wherein the function, F(SOC, temp) is calculated by a following relational equation:

F(SOC, temp)=F(temp)₅×

SOC⁵+F(temp)₄×

SOC⁴+F(temp)₃×

SOC³+F(temp)₂×

SOC²+F(temp)₁×

SOC+F(temp)₀

where F(temp)=D₂×

temp²+D₁×

temp¹+D₀(D₀˜

D₂;

constant).

3. The method according to claim 1, wherein the degradation of the output depending on the discharged capacity of the battery is expressed by a following equation:

F(accumulated discharge Ah)=−

16.3986k⁵+15.0026k⁴+13.307k³−

8.38698k²−

7.96289k+82.3028.

4. The method according to claim 3, further comprising a step of transmitting the estimated maximum output to a vehicle control device of the hybrid electric vehicle via a battery management system (BMS) to control the charge or discharge output of the battery.

5. The method according to claim 1, further comprising a step of transmitting the estimated maximum output to a vehicle control device of the hybrid electric vehicle via a battery management system (BMS) to control the charge or discharge output of the battery.