Method for Ascertaining the Open Circuit Voltage of a Battery, Battery with a Module for Ascertaining the Open Circuit Voltage and a Motor Vehicle Having a Corresponding Battery

• US 20130314042A1
• Filed: 11/21/2011
• Published: 11/28/2013
• Est. Priority Date: 11/30/2010
• Status: Abandoned Application

• Current Assignee: Robert Bosch GmbH, Samsung SDI Company Limited
• Original Assignee: Robert Bosch GmbH, Samsung SDI Company Limited
• Inventors: Boehm, Andre, Wickert, Stefan
• Application Number:
  US13/990,507
• Publication Number:
  US 20130314042A1
• Time in Patent Office: Days
• US Class Current: 320/109
• 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: G01R 31/367 Software therefor, e.g. for battery testing using modelling or look-up tables
• 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

The present disclosure relates to a method for ascertaining the open circuit voltage (OCV) of a battery, to a battery with a module configured to ascertain the open circuit voltage and to a motor vehicle having a corresponding battery, which is configured to ascertain the ageing-dependent open circuit voltage of battery packs installed in a vehicle. To this end it is proposed to determine the open circuit voltage during the charging operation of the battery. Furthermore proposed are a battery having a module for ascertaining the open circuit voltage of a battery, and a vehicle having a battery of this type.

Claims

1. A method for ascertaining the open circuit voltage of a battery, comprising:

determining the open circuit voltage during a charging process of the battery.

2. The method as claimed in claim 1, wherein the battery includes at least one electrochemical cell defining a cell voltage, and the method further comprises:

ascertaining a voltage drop at an impedance of the at least one electromechanical cell, and

subtracting the voltage drop from the cell voltage in order to ascertain the open circuit voltage.

3. The method as claimed in claim 2, further comprising:

using a cell model of a battery management system to ascertain the voltage drop.

4. The method as claimed in claim 3, wherein at least one of (i) a characteristic curve of the open circuit voltage used in the battery management system, and (ii) an OCV table is adapted as a function of the determined open circuit voltage.

5. The method as claimed in claim 1, further comprising:

keeping the charging current constant during the charging process.

6. The method as claimed in claim 1, further comprising:

changing the charging current during the charging process.

7. The method as claimed in claim 2, further comprising:

ascertaining the cell voltage; and

filtering out faults in at least one of the ascertainment of the voltage drop, and the ascertainment of the cell voltage.

8. The method as claimed in claim 1, further comprising:

determining the open circuit voltage over an entire range of a state of charge of the battery.

9. A battery comprising:

a module configured to carry out a method for ascertaining an open circuit voltage of the battery,

wherein the method includes determining the open circuit voltage during a charging process of the battery.

10. A motor vehicle comprising:

an electric drive motor configured to drive the motor vehicle, and

a battery configured to be connected to the electric drive motor, the battery including a module configured to carry out a method for ascertaining an open circuit voltage of the battery,

wherein the method includes determining the open circuit voltage during a charging process of the battery.