Method for determining the temperature of a battery

Patent metadata

Field	Value
Publication number	US-9819061-B2
Application number	US-201515309688-A
Country	US
Kind code	B2
Filing date	Apr 13, 2015
Priority date	May 12, 2014
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

The invention relates to a method for determining the temperature of a battery, comprising the following steps: a) determining the state of charge of at least one battery cell; b) determining a change in the open-circuit voltage (V L1 , V L2 ) of the at least one battery cell immediately after the end of the flow of an electric current (I L , I E ) through the at least one battery cell; and c) determining the temperature of the at least one battery cell on the basis of the state of charge and the change in the open-circuit voltage (V L1 , V L2 ). The method described above economically enables especially reliable operation of the battery that is stable over the long term.

First claim

The invention claimed is:

1. A method for determining the temperature of a battery, comprising the following steps:
a) determining the state of charge of at least one battery cell;
b) determining a change in an open-circuit voltage (V L1 or V L2 ) of the at least one battery cell immediately after the end of the flow of a respective electric current (I E , I L ) through the at least one battery cell; and
c) determining the temperature of the at least one battery cell on the basis of the state of charge and the change in the open-circuit voltage (V L1 or V L2 ).

2. The method according to claim 1 , wherein the determined temperature is verified by the use of a temperature sensor.

3. The method according to claim 1 , wherein the change in the open-circuit voltage (V L1 , V L2 ) is determined cyclically.

4. The method according to claim 1 , wherein the change in the open-circuit voltage (V L1 , V L2 ) is determined during a recuperation phase of the battery.

5. The method according to claim 1 , wherein the battery is a lithium-ion battery.

6. The method according to claim 1 , wherein step c) of the method is carried out using a temporal change in the open-circuit voltage (V L1 , V L2 ).

7. The method according to claim 6 , wherein step c) of the method is carried out using an entire profile of the change in the open-circuit voltage (V L1 , V L2 ).

8. The method according to claim 1 , wherein the method is carried out by means of a battery control system.

9. The method according to claim 8 , wherein step c) of the method is carried out on the basis of a data set that is stored the battery control system.

10. A battery system comprising a battery having at least one battery cell, the system comprising:
a means for determining the state of charge of the battery cell,
a means for determining a change in an open-circuit voltage (V L1 or V L2 ) of the at least one battery cell immediately after the end of the flow of a respective electric current (I E , I L ) through the at least one battery cell, and
a means for determining the temperature of the at least one battery cell on the basis of the state of charge and the change in the open-circuit voltage (V L1 or V L2 ).

Assignees

• Bosch Gmbh Robert

Inventors

• Reitzle Alexander
• Hore Sarmimala

Classifications

• H01M10/486 Primary

  for measuring temperature · CPC title

• H01M10/48 Primary

  Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte (constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569) · CPC title

• G01K13/00

  Thermometers specially adapted for specific purposes · CPC title

• G01R31/3835

  involving only voltage measurements · CPC title

• H01M2220/20

  Batteries in motive systems, e.g. vehicle, ship, plane · CPC title