Battery pack

• US 9,465,079 B2
• Filed: 06/20/2014
• Issued: 10/11/2016
• Est. Priority Date: 06/25/2013
• Status: Active Grant

• Current Assignee: Makita Corporation
• Original Assignee: Makita Corporation
• Inventors: Suzuki, Hitoshi, Fukumoto, Masaaki, Nagasaka, Hidenori
• Primary Examiner(s): FLETCHER, MARLON T
• Application Number:
  US14/310,939
• Publication Number:
  US 20140375231A1
• Time in Patent Office: 844 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: G01R 31/382 Arrangements for monitoring battery or accumulator variables, e.g. SoC
• CPC Class Codes: H01M 10/4257 Smart batteries, e.g. electronic circuits inside the housing of the cells or 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: H01M 10/486 for measuring temperature
• CPC Class Codes: H01M 50/213 adapted for cells having curved cross-section, e.g. round or elliptic H01M50/209, H01M50/216 take precedence
• CPC Class Codes: H01M 50/244 Secondary casings; Racks; Suspension devices; Carrying devices; Holders characterised by their mounting method
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: H02J 7/0049 Detection of fully charged condition
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A battery pack includes: a battery; a notification unit configured to notify that a fully charged state is reached; a determination unit configured to determine whether the fully charged state is reached; a processing unit configured to execute a full charge process if the fully charged state is determined, the full charge process being one of causing the notification unit to make a notification and maintaining a possible state, in which making a notification is possible; and a factor detection unit configured to detect occurrence of a predetermined increase factor during execution of the full charge process, the increase factor leading to increase in a chargeable capacity of the battery as compared with the time when the fully charged state is determined. The processing unit stops the full charge process if occurrence of the increase factor is detected during execution of the full charge process.

Claims

1. A battery pack, comprising:

a battery comprising a secondary battery;

a temperature detection unit configured to detect a temperature of the battery;

a notification unit configured to notify that the battery is in a fully charged state;

a determination unit configured to determine whether the battery is in the fully charged state;

a processing unit configured to execute a full charge process if it is determined by the determination unit that the battery is in the fully charged state, the full charge process being one of causing the notification unit to make a notification and maintaining a possible state, in which making a notification by the notification unit is possible; and

a factor detection unit configured to detect, as an increase factor that leads to an increase in a chargeable capacity of the battery, that a current temperature of the batter detected by the temperature detection unit has risen from a temperature at the time when it is determined by the determination unit that the battery is in the fully charged state,

wherein the processing unit stops the full charge process if occurrence of the at least one predetermined increase factor is detected by the factor detection unit during the execution of the full charge process.

2. The battery pack according to claim 1, further comprising:

a request detection unit configured to detect a predetermined notification request to cause the notification unit to make a notification,

wherein the processing unit executes the full charge process of maintaining the possible state, and also causes the notification unit to make a notification if the notification request is detected by the request detection unit during the execution of the full charge process.

3. The battery pack according to claim 1, further comprising:

a request detection unit configured to detect a predetermined notification request to cause the notification unit to make a notification,

wherein the determination unit determines whether the battery is in the fully charged state if the notification request is detected by the request detection unit, and

wherein the processing unit executes the full charge process of causing the notification unit to make a notification.

4. The battery pack according to claim 2,

wherein the request detection unit includes a behavior detection unit configured to detect a behavior of the battery pack, and detects, if a predetermined behavior is detected by the behavior detection unit, the behavior as the notification request.

5. The battery pack according to claim 1,

wherein the factor detection unit detects occurrence of the increase factor when the temperature of the battery has risen from a predetermined low temperature range to a normal temperature range higher than the low temperature range.

6. The battery pack according to claim 1,

wherein three or more types of temperature ranges of the temperature of the battery are defined, and

wherein the factor detection unit detects occurrence of the increase factor when the temperature of the battery has risen thereby to change a temperature range in which the temperature is included.

7. The battery pack according to claim 1,

wherein the battery comprises a plurality of cells, and

wherein the determination unit determines whether the battery is in the fully charged state on the basis of a highest cell voltage among cell voltages of the plurality of cells.

8. The battery pack according to claim 1,

wherein, after determining that the battery is in the fully charged state, the determination unit cancels a determination that the battery is in the fully charged state when the increase factor is detected by the factor detection unit.

9. The battery pack according to claim 8,

wherein, after determining that the battery is in the fully charged state, the determination unit resets a flag showing that the battery is in the fully charged state when the increase factor is detected by the factor detection unit.