Lifetime estimation device, lifetime estimation method, and abnormality detection method of secondary battery

Patent metadata

Field	Value
Publication number	US-11340306-B2
Application number	US-201816761289-A
Country	US
Kind code	B2
Filing date	Nov 7, 2018
Priority date	Nov 16, 2017
Publication date	May 24, 2022
Grant date	May 24, 2022

Abstract

An object is to predict a deterioration state of a secondary battery even in an environment where temperature and a charging voltage change. A lifetime estimation device of the secondary battery includes a measuring unit for measuring the capacity of the secondary battery in the full charging state; a temperature sensing unit for sensing the ambient temperature of the secondary battery; and a storage unit for storing a table of a proportional coefficient corresponding to temperature in advance, and a predicted deterioration line of the secondary battery is calculated with the use of a nonlinear regression equation approximated to a measured deterioration line obtained by the measuring unit. The lifetime estimation device may construct a lifetime estimation system with the use of a neural network.

First claim

The invention claimed is:

1. A lifetime estimation device of a secondary battery, comprising:
a measuring unit measuring a capacity of a secondary battery in a full charging state;
a temperature sensing unit sensing ambient temperature of the secondary battery;
a storage unit storing a table of a proportional coefficient corresponding to temperature; and
a microcomputer calculating a predicted deterioration line of the secondary battery with use of a nonlinear regression equation approximated to a measured deterioration line obtained by the measuring unit,
wherein the nonlinear regression equation is represented by:
State of Health(SOH)=100− a ×√{square root over (Cycle number)}− b ×(Cycle number) 2 ,

wherein the SOH means a capacity retention rate to an initial capacity of the secondary battery, represented by percentage,
wherein the Cycle number means a number of a pair of charge and discharge of the secondary battery,
wherein each of parameters a and b represents a positive number, and
wherein the table of the proportional coefficient comprises parameters a and b.

2. The lifetime estimation device of a secondary battery according to claim 1 ,
wherein the nonlinear regression equation comprises a first proportional coefficient represented by parameter a and a second proportional coefficient represented by parameter b, and
wherein the storage unit is configured to store a table of the first proportional coefficient and a table of the second proportional coefficient.

3. The lifetime estimation device of a secondary battery according to claim 2 ,
wherein each of the first proportional coefficient and the second proportional coefficient is a deterioration factor.

4. The lifetime estimation device of a secondary battery according to claim 1 ,
wherein the storage unit is a database.

Assignees

• Semiconductor Energy Lab

Inventors

• Isa Toshiyuki
• Chida Akihiro
• Tajima Ryota

Classifications

• H01M10/48

  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

• G01R31/374

  with means for correcting the measurement for temperature or ageing · CPC title

• G01R31/3648

  comprising digital calculation means, e.g. for performing an algorithm · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• G01R31/392 Primary

  Determining battery ageing or deterioration, e.g. state of health · CPC title