US 6,441,587 B2 · Method to determine capacity of a battery

Abstract

This method to determine capacity of a battery computes capacity in current value and then converts it into capacity in power value, or computes capacity in power value and then converts it into current value. This method to determine capacity of a battery detects either discharge current or charge current or both, and computes capacity of battery in current value, which is then converted into capacity in power value by way of multiplication by the correcting constant which varies in accordance with capacity in current value. This method to determine capacity of a battery detects battery voltage or detects either discharge current or charge current or both of the battery, then computes battery capacity in power value, and converts capacity in power value so computed into capacity in current value by way of multiplication by the correcting constant which varies in accordance with capacity in power value.

Claims25

Dependent claims

A method to determine capacity of a battery, comprising:

(1) detecting at least one of discharge current value and charge current value of the battery from a prescribed capacity state of the battery;
(2) computing remaining battery capacity in current value, being units of quantity of electricity, based on the detected current value;
and
(3) computing remaining battery capacity in power value, being units of electrical energy, by converting the computed remaining battery capacity in current value using a selected one of a plurality of correcting constants that vary in accordance with the computed remaining battery capacity in current value.

1 more element

A method to determine capacity of a battery pack, comprising:

(1) detecting consumed current of the battery and converting the detected consumed current into corresponding voltage at a consumed current/voltage detector;
(2) detecting voltage of battery at a voltage detector;
(3) converting analogue signals outputted by the consumed current/voltage detector into digital signals at a first A/D converter;
(4) converting analogue signals outputted by the voltage detector into digital signals at a second A/D converter;
(5) determining either consumed electric power of the battery, which is based on the digital signals of the first A/D converter, and the second A/D converter or consumed current based on the digital signals output by the first A/D converter using a multiplier;
(6) detecting a discharge termination voltage based on the digital signals outputted at the second A/D converter by using a low battery detector;
(7) generating trigger signals for converting the analogue signals into the digital signals for transmission to the first A/D converter and the second A/D converter at prescribed intervals by using a timer;
(8) computing remaining battery capacity by subtracting either the consumed current or the consumed electric power from fully charged capacity by using a remaining capacity calculator;
(9) converting either the remaining battery capacity computed at the remaining capacity calculator or a multiplication result signal outputted at the multiplier from current value into power value, or power value into current value, by using a converter;
and
(10) transmitting the remaining capacity to an electronic device.

8 more elements

Dependencies are inferred from the claim text.

Method to determine capacity of a battery

Life of this patent

Method to determine capacity of a battery

Life of this patent

Abstract

Claims25