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US 2003/0193318 A1Published application
Method for predicting remaining charge of portable electronics battery
AssigneeFujitsu Limited
InventorsHidekiyo Ozawa, Shigeo Tanaka
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AssigneeFujitsu Limited
InventorsHidekiyo Ozawa, Shigeo Tanaka
Estimating the term…
A remaining charge predicting method which improves the precision of predicting the remaining charge of a rechargeable battery. A battery pack has a measuring circuit which monitors a charge current, discharge current, the voltage of the rechargeable battery and the temperature of the battery. The measuring circuit notifies a power management microcomputer, provided in a portable device, of the measured current, voltage and temperature. The power management microcomputer predicts the remaining charge of the battery based on the received measured values. The battery pack does not perform data processing for predicting the remaining charge.
A method for predicting remaining charge in at least one rechargeable battery provided in a battery pack for supplying power to a portable device, the method comprising:
An analog-digital conversion circuit comprising:
A method for controlling charging of a rechargeable battery provided in a battery pack to be connected to a portable device, the method comprising:
A method for controlling charging of a rechargeable battery provided in a battery pack which is to be connected to a portable device and includes a first terminal for supplying charge current and charge voltage to said rechargeable battery from an external power supply and a second terminal for outputting a signal having a voltage nearly equal to a battery voltage of said rechargeable battery, said method comprising:
A method for controlling charging of a rechargeable battery provided in a battery pack which is connectable to a portable device and includes a first terminal for supplying charge current and charge voltage to said rechargeable battery from an external power supply and a second terminal for outputting a signal having a voltage nearly equal to a battery voltage of said rechargeable battery, said method comprising:
A method for controlling a power supply of a portable device which has a standby power supply and is connected to a battery pack including at least one rechargeable battery, a first terminal for supplying power from said rechargeable battery to said portable device and a second terminal for outputting a signal having a voltage nearly equal to a battery voltage of said rechargeable battery, said method comprising:
A battery pack having at least one rechargeable battery, comprising:
A semiconductor device used in a battery pack having at least one rechargeable battery, comprising:
A portable device which is driven by power supplied from a battery pack, wherein the battery pack includes a rechargeable battery, a current detection circuit for detecting a current flowing into or flowing out of said rechargeable battery and generating an analog current detection signal, a voltage detection circuit for detecting a voltage of said rechargeable battery and generating an analog voltage detection signal, an analog-digital conversion circuit, connected to said current detection circuit and said voltage detection circuit, for converting said current detection signal and said voltage detection signal to digital signals, and an interface for outputting said digital signals, the portable device comprising:
A method for manufacturing an apparatus for predicting remaining charge of at least one rechargeable battery provided in a battery pack for a portable device, comprising:
Dependencies are inferred from the claim text.
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This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2002-112008 filed on Apr. 15, 2002, the entire contents of which are incorporated herein by reference.
The present invention relates to a method for predicting remaining charge of a battery, such as a rechargeable battery of a portable electronic device.
In general, chargeable lithium ion batteries are widely used for portable electronic devices, such as notebook personal computers. The lithium ion batteries have advantages such that the operational cost of portable electronic devices can be reduced and the capacity of the current which is instantaneously dischargeable is large. Normally, a machine which has a rechargeable battery so called secondary battery, such as a lithium ion battery, installed therein incorporates a charging circuit which is to be connected to an external power supply to charge the rechargeable battery. To meet the demands for higher performance and size reduction, recent portable devices require a compact charging circuit which can quickly charge a rechargeable battery to a full level. General portable electronic devices include a capability for predicting the remaining charge of a rechargeable battery, when they are in use, in order to avoid problems with data loss by notifying users of the consumption states of the batteries. The prediction of the remaining battery charge should be carried out accurately.
The invention, together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which:
FIG. 1 is a schematic block circuit diagram of an ordinary portable electronic device connected to a battery pack;
FIGS. 2A, 2B, 3, 4 and 5 are graphs showing the characteristics of rechargeable batteries;
A first embodiment of the present invention will be described below.
FIG. 8 is a schematic block circuit diagram of a battery pack 12 and a portable electronic device 11 according to the first embodiment.
The portable device 11, connected to the battery pack 12, is driven by the battery pack 12. The portable device 11 is connectable to an external power supply via an AC adapter 13.