Autonomic battery reconditioning

• US 20050156570A1
• Filed: 12/17/2004
• Published: 07/21/2005
• Est. Priority Date: 12/22/2003
• Status: Active Grant

• Current Assignee: Lenovo PC International Limited (Lenovo Group Ltd.)
• Original Assignee: International Business Machines Corporation
• Inventors: Tadokoro, Mizuho, Inui, Takashi
• Granted Patent: US 7,466,105 B2
• Time in Patent Office: Days
• US Class Current: 320/132
• 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: H02J 7/0069 Charging or discharging for charge maintenance, battery initiation or rejuvenation

Abstract

An information processing apparatus that is driven by a rechargeable battery, wherein the battery is depleted from a fully charged state and repeatedly charged and discharged, comprises a full charge capacity acquisition unit for acquiring a present full charge capacity of the battery which the battery has at the present time, a total charge acquiring unit for acquiring information indicating a total amount of charge provided to the battery in a time period from a start time of using the battery until the present full charge capacity is acquired, and a restoring unit for performing a battery restoration in which the battery is fully discharged or fully charged in order to recover the full charge capacity if it is determined that the present full charge capacity is smaller than an expected full charge capacity that the battery should have depending on the information.

Claims

1. Apparatus comprising:

a rechargeable battery;

a full charge capacity circuit, coupled to said battery, which acquires a present full charge capacity that is a full charge capacity which said battery has at the present time, the full charge capacity being a capacity in a state where said battery is fully charged, and the full charge capacity being decreased by repeatedly charging or discharging said battery;

a total charge circuit, coupled to said battery, which acquire information indicating a total amount of charge provided to said battery in a time period from a start time of using said battery until the present full charge capacity is acquired; and

a first circuit, coupled to said battery, which performs battery restoration by fully discharging or fully charging said battery if the present full charge capacity is smaller than an expected full charge capacity that said battery should have depending on the information.

2. Apparatus according to claim 1, further comprising an expected capacity circuit, coupled to said total charge circuit and said first circuit, which calculates an expected capacity that is the expected full charge capacity, based on the full charge capacity at the start time of using said battery and the total amount of charge, wherein said first circuit performs the battery restoration, if the present full charge capacity acquired is smaller than the expected capacity calculated by said expected capacity circuit.

3. Apparatus according to claim 2, wherein said total charge circuit acquires a cycle count that increments by one every time the total amount of charge reaches a predetermined percentage of the full charge capacity, as the information indicating the total amount of charge, and said expected capacity circuit calculates the expected capacity by subtracting a decrease amount of the full charge capacity decreasing at one cycle count, multiplied by the acquired cycle count, from the full charge capacity at the start time of using said battery.

4. Apparatus according to claim 3, wherein said expected capacity circuit calculates, as the full charge capacity at the start time of using said battery, the full charge capacity before starting the use of said battery after the battery restoration to which the decrease amount of the full charge capacity decreasing at one cycle count multiplied by the cycle count at the time of performing the battery restoration is added.

5. Apparatus according to claim 1, wherein said first circuit calculates a decrease rate at which the full charge capacity of said battery decreases in accordance with the total amount of charge, based on a plurality of the present full charge capacities and a plurality of the total amount of charge that are acquired, and judges that the present full charge capacity of said battery is smaller than the expected full charge capacity, if the calculated decrease rate is higher than a preset reference decrease rate corresponding to said battery.

6. Apparatus comprising:

a rechargeable battery;

an AC-driven circuit which acquires information indicating a time period in which said apparatus was being driven by an AC power supply;

a full discharge period circuit, coupled to said battery, which calculates full discharge time, said full discharge time being a first estimation of time required for said battery to be fully discharged;

a full charge time circuit, coupled to said battery, which calculates full charge time, the full charge time being a second estimation of time required for said battery to become fully charged after being fully discharged; and

a first circuit, coupled to said battery and to said AC-driven circuit, which performs a battery restoration by fully discharging and then fully charging said battery if a time period from a lapse of said full discharge time until the lapse of said full charge time is a time period in which a ratio of a time duration in which said apparatus has been being driven by said AC power supply to a time duration in which said apparatus has been driven is higher than a predetermined reference ratio.

7. A method comprising:

controlling a rechargeable battery in an information processing apparatus driven by the rechargeable battery, by;

acquiring a present full charge capacity that is a full charge capacity which said battery has at the present time, said full charge capacity being a capacity in a state where said battery is fully charged, and said full charge capacity being decreased by repeatedly charging or discharging said battery;

acquiring information indicating a total amount of charge provided to said battery in a time period from a start time of using said battery until said present full charge capacity is acquired; and

performing a battery restoration by fully discharging or fully charging said battery if the present full charge capacity acquired is smaller than an expected full charge capacity that said battery should have depending on the information.

8. A product comprising:

a computer usable medium having computer readable program code stored therein for use with a information processing apparatus driven by a rechargeable battery, the computer readable program code in said product being effective to;

acquire a present full charge capacity that is a full charge capacity which said battery has at the present time, said full charge capacity being a capacity in a state where said battery is fully charged, and said full charge capacity being decreased by repeatedly charging or discharging said battery;

acquire information indicating a total amount of charge provided to said battery in a time period from a start time of using said battery until said present full charge capacity is acquired; and

perform a battery restoration by fully discharging or fully charging said battery if the present full charge capacity acquired is smaller than an expected full charge capacity that said battery should have depending on the information.