Method for determining the internal ohmic resistance of a battery module, battery management system and motor vehicle
AssigneesRobert Bosch GmbH, Samsung SDI Co., Ltd.
InventorHolger Fink
Life of this patent
Estimating the term…
Abstract
A method for determining an internal ohmic resistance of a first battery module includes measuring a first voltage intensity of the first battery module. The first battery module is connected to at least a second battery module. The at least second battery module is under a load current. A second voltage intensity of the first battery module is measured. The first battery module is disconnected from the at least second battery module to enable the measurement of the first voltage intensity and the connection of the first battery module.
Claims14
A method for determining an impedance of a first battery module of at least two battery modules in a battery module string, the method comprising:
- performing repeated connection and disconnection of the first battery module to and from a second battery module of the at least two battery modules in the battery module string while the battery module string is under a load current, each repeated connection and disconnection of the first battery module taking place with a predetermined time period between successive connections and a varying time period between a connection and a subsequent disconnection;
- measuring voltage intensities of the first battery module (i) prior to the connection of the first battery module to the second battery module and (ii) after the disconnection of the first battery module to the second battery module;
- determining changes in the measured voltage intensities;
- and
- determine an impedance the first battery module based on the changes.
A battery management system for a battery module string, the battery module string including (i) at least two battery modules, (ii) a first apparatus configured to measure battery module voltage intensities under load, and (iii) a second apparatus configured to transmit the measured battery module voltage intensities to the battery management system, the battery management system is configured to:
- receive battery module voltage intensities from the battery module string;
- determine changes in the received battery module voltage intensities of a first battery module of the at least two battery modules, the first battery module being repeatedly connected to and disconnected from a second battery module of the at least two battery modules while the battery module string is under a load current, the battery module voltage intensities of the first battery module being measured (i) prior to the connection of the first battery module to the second battery module and (ii) after the disconnection of the first battery module from the second battery module;
- and
- determine an impedance of one of the at least two battery modules based on the changes,
- wherein the battery module string is connected to the battery management system.
A battery system comprising:
- a battery module string comprising:
- at least two battery modules;
- a first apparatus configured to measure battery module voltage intensities under load;
- and
- a second apparatus configured to transmit the measured battery module voltage intensities;
- and
- a battery management system connected to the battery module string, the battery management system configured to:
- receive battery module voltage intensities from the battery module string;
- determine changes in the received battery module voltage intensities of a first battery module of the at least two battery modules, the first battery module being repeatedly connected to and disconnected from a second battery module of the at least two battery modules while the battery module string is under a load current, the battery module voltage intensities of the first battery module measured (i) prior to the connection of the first battery module to the second battery module and (ii) after the disconnection of the first battery module from the second battery module;
- and
- determine an impedance of one of the at least two battery modules based on the changes.
Dependencies are inferred from the claim text.