US 8,359,174 B2 · Battery pack, electronic appliance, and method of detecting remaining amount of battery

Abstract

A battery pack has a charge and discharge count measuring part (131) configured to measure the number of times of charges and discharges of a secondary battery based on the summed value of the charge current for the secondary battery, and a decay rate output part (132) configured to compute a decay rate that indicates a degree of decay of the secondary battery based on the number of times of charges and discharges measured by the charge and discharge count measuring part (131) and to output it to a device being a discharge load. For example, the charge and discharge count measuring part (131) repeatedly sums the detected values of the charge current to a predetermined threshold, and counts up the number of times of charges and discharges every time when the summed value reaches the threshold. Accordingly, even though charges and discharges are repeated at finer steps in a relatively narrow voltage range, the number of times of charges and discharges can be counted accurately, and the computing accuracy of the decay rate is improved. In the battery pack in which the secondary battery is accommodated, parameters for detecting the remaining amount of the battery are detected more accurately.

Claims19

Dependent claims

A battery pack in which a processing circuit which performs a predetermined process based on various detected values from a secondary battery is accommodated in one piece with the secondary battery, the battery pack characterized by comprising:

a charge current summing part configured to sum a detected value of charge current for the secondary battery;
a charge and discharge count measuring part configured to measure the number of times of charges and discharges of the secondary battery based on the summed value of the charge current by the charge current summing part;
a decay rate computing part configured to compute a decay rate that indicates a degree of decay of the secondary battery based on the number of times of charges and discharges measured by the charge and discharge count measuring part;
and
a communicating part configured to output the decay rate computed by the decay rate computing part to an external device that is a discharge load of the secondary battery,
wherein the charge current summing part sums a magnitude of the charge current for every fixed time period, and
wherein the charge and discharge count measuring part decides the added value of the number of times of charges and discharges based on the summed value of the charge current for each of the fixed time periods from the charge current summing part, and adds the added value to the number of times of charges and discharges computed immediately before for output.

4 more elements

a charge current summing part configured to sum a detected value of charge current for the secondary battery;
a charge and discharge count measuring part configured to measure the number of times of charges and discharges of the secondary battery based on the summed value of the charge current by the charge current summing part;
a decay rate computing part configured to compute a decay rate that indicates a degree of decay of the secondary battery based on the number of times of charges and discharges measured by the charge and discharge count measuring part;
a communicating part configured to output the decay rate computed by the decay rate computing part to an external device that is a discharge load of the secondary battery;
a charge and discharge current summing part configured to sum a detected value of charge and discharge current of the secondary battery;
a voltage detecting part configured to detect a voltage between a positive electrode and a negative electrode of the secondary battery;
and
a summed value correcting part configured to preset a tolerance for errors in which the summed value of charge and discharge current takes a fixed width around an approximated line that a curve associating voltage between a positive electrode and a negative electrode of the secondary battery when an electrode of the secondary battery is opened with the summed value of charge and discharge current by means of a graph, and to correct the summed value of charge and discharge current by the charge and discharge current summing part so as to be included in the tolerance for errors in accordance with a detected value of voltage at this time by the voltage detecting part,
wherein the communicating part outputs the summed value of charge and discharge current connected by the summed value correcting part to the external device together with the decay rate.

6 more elements

An electronic appliance which operates by receiving power from a secondary battery, the electronic appliance characterized by comprising:

a detachable battery pack configured to have a processing circuit which performs a predetermined process based on various detected values from the secondary battery accommodated therein together with the secondary battery in one piece;
a first communicating part configured to communicate with the battery pack;
and
a battery remaining amount computing means configured to receive a summed value of charge and discharge current of the secondary battery and a decay rate that indicates a degree of decay of the secondary battery from the battery pack through the first communicating part and to compute a remaining amount of the secondary battery,
wherein the battery pack includes:
a charge current summing part configured to sum a detected value of charge current for the secondary battery;
a charge and discharge count measuring part configured to measure the number of times of charges and discharges of the secondary battery based on the summed value of the charge current by the charge current summing part;
a decay rate computing part configured to compute the decay rate based on the number of times of charges and discharges measured by the charge and discharge count measuring part;
a charge and discharge current summing part configured to sum a detected value of the charge and discharge current of the secondary battery;
and
a second communicating part configured to output the decay rate computing part and the summed value of charge and discharge current by the charge and discharge current summing part to the first communicating part,
wherein the charge current summing part sums a magnitude of the charge current for every fixed time period, and
wherein the charge and discharge count measuring part decides the added value of the number of times of charges and discharges based on the summed value of the charge current for each of the fixed time periods from the charge current summing part, and adds the added value to the number of times of charges and discharges computed immediately before for output.

10 more elements

An electronic appliance which operates by receiving power from a secondary battery, the electronic appliance characterized by comprising:

a detachable battery pack configured to have a processing circuit which performs a predetermined process based on various detected values from the secondary battery accommodated therein together with the secondary battery in one piece;
a first communicating part configured to communicate with the battery pack;
and
a battery remaining amount computing means configured to receive a summed value of charge and discharge current of the secondary battery and a decay rate that indicates a degree of decay of the secondary battery from the battery pack through the first communicating part and to compute a remaining amount of the secondary battery,
wherein the battery pack includes:
a charge current summing part configured to sum a detected value of charge current for the secondary battery;
a charge and discharge count measuring part configured to measure the number of times of charges and discharges of the secondary battery based on the summed value of the charge current by the charge current summing part;
a decay rate computing part configured to compute the decay rate based on the number of times of charges and discharges measured by the charge and discharge count measuring part;
a charge and discharge current summing part configured to sum a detected value of the charge and discharge current of the secondary battery;
and
a second communicating part configured to output the decay rate computing part and the summed value of charge and discharge current by the charge and discharge current summing part to the first communicating part,
wherein the decay rate computing part associates in advance the number of times of charges and discharges with the decay rate by means of a graph having at least two points of change in a slope, and converts the number of times of charges and discharges measured by the charge and discharge count measuring part into the decay rate based on the graph.

9 more elements

An electronic appliance which operates by receiving power from a secondary battery, the electronic appliance characterized by comprising:

a detachable battery pack configured to have a processing circuit which performs a predetermined process based on various detected values from the secondary battery accommodated therein together with the secondary battery in one piece;
a first communicating part configured to communicate with the battery pack;
and
a battery remaining amount computing means configured to receive a summed value of charge and discharge current of the secondary battery and a decay rate that indicates a degree of decay of the secondary battery from the battery pack through the first communicating part and to compute a remaining amount of the secondary battery,
wherein the battery pack includes:
a charge current summing part configured to sum a detected value of charge current for the secondary battery;
a charge and discharge count measuring part configured to measure the number of times of charges and discharges of the secondary battery based on the summed value of the charge current by the charge current summing part;
a decay rate computing part configured to compute the decay rate based on the number of times of charges and discharges measured by the charge and discharge count measuring part;
a charge and discharge current summing part configured to sum a detected value of the charge and discharge current of the secondary battery;
a second communicating part configured to output the decay rate computing part and the summed value of charge and discharge current by the charge and discharge current summing part to the first communicating part;
a charge and discharge current summing part configured to sum a detected value of charge and discharge current of the secondary battery;
a voltage detecting part configured to detect a voltage between a positive electrode and a negative electrode of the secondary battery;
and
a summed value correcting part configured to preset a tolerance for errors in which the summed value of charge and discharge current takes a fixed width around an approximated line that a curve associating voltage between a positive electrode and a negative electrode of the secondary battery when an electrode of the secondary battery is opened with the summed value of charge and discharge current by means of a graph, and to correct the summed value of charge and discharge current by the charge and discharge current summing part so as to be included in the tolerance for errors in accordance with a detected value of voltage at this time by the voltage detecting part,
wherein the communicating part outputs the summed value of charge and discharge current connected by the summed value correcting part to the external device together with the decay rate.

12 more elements

An electronic appliance which operates by receiving power from a secondary battery, the electronic appliance characterized by comprising:

a detachable battery pack configured to have a processing circuit which performs a predetermined process based on various detected values from the secondary battery accommodated therein together with the secondary battery in one piece;
a first communicating part configured to communicate with the battery pack;
and
a battery remaining amount computing means configured to receive a summed value of charge and discharge current of the secondary battery and a decay rate that indicates a degree of decay of the secondary battery from the battery pack through the first communicating part and to compute a remaining amount of the secondary battery,
wherein the battery pack includes:
a charge current summing part configured to sum a detected value of charge current for the secondary battery;
a charge and discharge count measuring part configured to measure the number of times of charges and discharges of the secondary battery based on the summed value of the charge current by the charge current summing part;
a decay rate computing part configured to compute the decay rate based on the number of times of charges and discharges measured by the charge and discharge count measuring part;
a charge and discharge current summing part configured to sum a detected value of the charge and discharge current of the secondary battery;
a second communicating part configured to output the decay rate computing part and the summed value of charge and discharge current by the charge and discharge current summing part to the first communicating part;
a voltage detecting part configured to detect a voltage between a positive electrode and a negative electrode of the secondary battery;
and
a summed value correcting part configured to preset a tolerance for errors in which the summed value of charge current takes a fixed width around an approximated line that a curve associating voltage between a positive electrode and a negative electrode of the secondary battery when an electrode of the secondary battery is opened with the summed value of charge current by means of a graph, to correct the summed value of charge current by the charge current summing part so as to be included in the tolerance for errors in accordance with a detected value of voltage at this time by the voltage detecting part, and to supply it to the charge and discharge count measuring part.

10 more elements

A method of detecting a remaining amount of a battery for detecting a remaining amount of a secondary battery, the method comprising the steps of:

summing a detected value of charge current for the secondary battery by a charge current summing part disposed in a battery pack in which the secondary battery is accommodated;
measuring the number of times of charges and discharges of the secondary battery based on the summed value of the charge current by means of the charge current summing part by a charge and discharge count measuring part disposed in the battery pack;
computing a decay rate that indicates a degree of decay of the secondary battery based on the number of times of charges and discharges measured by means of the charge and discharge count measuring part by a decay rate computing part disposed in the battery pack;
summing a detected value of charge and discharge current of the secondary battery by a charge and discharge current summing part disposed in the battery pack;
computing a remaining amount of the secondary battery based on the decay rate computed by means of the decay rate computing part and the summed value of charge and discharge current by means of the charge and discharge current summing part by a battery remaining amount computing means disposed in an electronic appliance that is a discharge load of the secondary battery;
detecting a voltage by a voltage detecting part between a positive electrode and a negative electrode of the secondary battery;
and
presetting a tolerance for errors by a summed value correcting part in which the summed value of charge and discharge current takes a fixed width around an approximated line that a curve associating voltage between a positive electrode and a negative electrode of the secondary battery when an electrode of the secondary battery is opened with the summed value of charge and discharge current by means of a graph, and to correct the summed value of charge and discharge current by the charge and discharge current summing part so as to be included in the tolerance for errors in accordance with a detected value of voltage at this time by the voltage detecting part,
wherein the charge and discharge current summing part is configured to sum a detected value of charge and discharge current of the secondary battery, and
wherein the communicating part outputs the summed value of charge and discharge current connected by the summed value correcting part to the external device together with the decay rate.

7 more elements

A method of detecting a remaining amount of a battery for detecting a remaining amount of a secondary battery, the method comprising the steps of:

summing a detected value of charge current for the secondary battery by a charge current summing part disposed in a battery pack in which the secondary battery is accommodated;
measuring the number of times of charges and discharges of the secondary battery based on the summed value of the charge current by means of the charge current summing part by a charge and discharge count measuring part disposed in the battery pack;
computing a decay rate that indicates a degree of decay of the secondary battery based on the number of times of charges and discharges measured by means of the charge and discharge count measuring part by a decay rate computing part disposed in the battery pack;
summing a detected value of charge and discharge current of the secondary battery by a charge and discharge current summing part disposed in the battery pack;
computing a remaining amount of the secondary battery based on the decay rate computed by means of the decay rate computing part and the summed value of charge and discharge current by means of the charge and discharge current summing part by a battery remaining amount computing means disposed in an electronic appliance that is a discharge load of the secondary battery;
detecting a voltage by a voltage detecting part between a positive electrode and a negative electrode of the secondary battery;
and
presetting a tolerance for errors by a summed value correcting part in which the summed value of charge current takes a fixed width around an approximated line that a curve associating voltage between a positive electrode and a negative electrode of the secondary battery when an electrode of the secondary battery is opened with the summed value of charge current by means of a graph, to correct the summed value of charge current by the charge current summing part so as to be included in the tolerance for errors in accordance with a detected value of voltage at this time by the voltage detecting part, and to supply it to the charge and discharge count measuring part.

5 more elements

Dependencies are inferred from the claim text.

Battery pack, electronic appliance, and method of detecting remaining amount of battery

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Battery pack, electronic appliance, and method of detecting remaining amount of battery

Life of this patent

Abstract

Claims19