DETERIORATION DEGREE ESTIMATION DEVICE AND DETERIORATION DEGREE ESTIMATION METHOD

• US 20180246174A1
• Filed: 08/26/2015
• Published: 08/30/2018
• Est. Priority Date: 08/26/2015
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: SHIMOSAWA, Hironobu, SAKAI, Kenichi, HOSAKA, Kenji, SHIRATSUCHI, Tomoyuki
• Granted Patent: US 11,022,653 B2
• Time in Patent Office: Days
• CPC Class Codes: G01R 31/389 Measuring internal impedance, internal conductance or related variables
• CPC Class Codes: G01R 31/392 Determining battery ageing or deterioration, e.g. state of health
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/48 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 Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

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.

Claims

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.