Battery charge rate estimation method, battery charge rate estimation device, and battery power supply system

摘要

PPROBLEM TO BE SOLVED: To provide a battery charging rate estimation method, a battery charging rate estimation device, and a battery power source system, capable of estimating a charging rate initial value stably and highly accurately, even if the battery power source system is started at any timing. PSOLUTION: Some of a charging rate initial value SOC 1 determined from a battery voltage at a starting time of the battery power source system, a charging rate initial value SOC 2 updated and stored following charge/discharge current accumulation at a last-time start finish time, and a charging rate initial value SOC 3 calculated from a stable open circuit voltage estimated based on a battery voltage measured as long as a prescribed time after last-time start finish is selected based on a battery suspension time Tx. When the suspension time Tx is shorter than the first suspension time T1, SOC 2 is selected (step S11), and when the suspension time Tx is longer than the first suspension time T1 and shorter than the second suspension time T2, SOC 3 is selected (step S13), and when the suspension time Tx is longer than the second suspension time T2, SOC 1 is selected (step S14), respectively. PCOPYRIGHT: (C)2008,JPO&INPIT