Deterioration degree estimation device and deterioration degree estimation method

Patent metadata

Field	Value
Publication number	US-2018246174-A1
Application number	US-201515754607-A
Country	US
Kind code	A1
Filing date	Aug 26, 2015
Priority date	Aug 26, 2015
Publication date	Aug 30, 2018
Grant date	—

Abstract

A deterioration degree estimation device includes an internal resistance detection unit, a deterioration management unit and a deterioration degree estimation unit. The internal resistance detection unit detects an internal resistance of a battery. The deterioration management unit manages a cycle deterioration of the battery. The deterioration degree estimation unit estimates a deterioration degree of the battery as an estimated deterioration degree based on an increase rate of the internal resistance. The deterioration degree estimation unit estimates the estimated deterioration degree such that the estimated deterioration degree decreases as the cycle deterioration increases, or such that the estimated deterioration degree increases as the cycle deterioration degree decreases.

First claim

1 . A deterioration degree estimation device comprising:
an internal resistance detection unit for detecting an internal resistance of a battery; a deterioration management unit for managing a cycle deterioration of the battery; and a deterioration degree estimation unit for estimating a deterioration degree of the battery as an estimated deterioration degree based on an increase rate of the internal resistance, the deterioration degree estimation unit estimates the estimated deterioration degree such that the estimated deterioration degree decreases as the cycle deterioration increases, or such that the estimated deterioration degree increases as the cycle deterioration decreases.

2 . The deterioration degree estimation device according to claim 1 , wherein
the deterioration management unit manages the cycle deterioration by calculating a current integration value of the battery.

3 . The deterioration degree estimation device according to claim 2 , wherein
the deterioration degree estimation unit stores a map representing a correspondence relationship between the increase rate of the internal resistance, the current integration value, and the estimated deterioration degree, and estimates the estimated deterioration degree with reference to the map.

4 . The deterioration degree estimation device according to claim 2 , wherein
the deterioration degree estimation unit corrects the increase rate of the internal resistance based on the current integration value.

5 . The deterioration degree estimation device according to claim 2 , wherein
the deterioration degree estimation unit calculates the deterioration degree of the battery corresponding to the increase rate of the internal resistance as a reference deterioration degree, corrects the reference deterioration degree based on the current integration value, and estimates a corrected reference deterioration degree as the estimated deterioration degree.

6 . The deterioration degree estimation device according to claim 1 , wherein
the deterioration degree estimation unit corrects the estimated deterioration degree based on a temperature of the battery.

7 . The deterioration degree estimation device according to claim 1 , wherein
the deterioration degree estimation unit corrects the estimated deterioration degree based on a charging state of the battery.

8 . A deterioration degree estimation method comprising:
detecting an internal resistance of a battery; managing at least one of a cycle deterioration of the battery and a storage deterioration of the battery using a battery controller having a CPU; and estimating a deterioration degree of the battery as an estimated deterioration degree of the battery using the battery controller based on an increase rate of the internal resistance such that the estimated deterioration degree decreases as the cycle deterioration increases, or such that the estimated deterioration degree increases as the cycle deterioration decreases.

Assignees

• Nissan Motor

Inventors

• Shimosawa Hironobu
• Sakai Kenichi
• Hosaka Kenji
• Shiratsuchi Tomoyuki

Classifications

• G01R31/389

  Measuring internal impedance, internal conductance or related variables · CPC title

• G01R31/392 Primary

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

• H02J7/00

  Circuit arrangements for charging or discharging batteries or for supplying loads from batteries · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• 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