Device for estimating cycle life of battery

Abstract

The invention relates to a device for estimating the cycle life of a battery, comprising a measuring unit, an observer unit, an adaptability parameter unit, an inner voltage estimating unit, an open-circuit voltage estimating unit, a battery cycle life computing unit and a battery residual electricity quantity estimator, wherein the measuring unit is used for measuring the working currents, the working voltages and the working temperature of the battery; the observer unit can observe the voltage of the output end of the battery and the voltage of an RC (Resistance Capacitance) parallel circuit of the battery; the adaptability parameter unit can update the parameter values of the battery; the inner voltage estimating unit can estimate the inner voltages of the RC parallel circuit of the battery; the open-circuit voltage estimating unit can compute the static open-circuit voltages of the battery; the battery cycle life computing unit can compute the cycle life value of the battery; and the battery residual electricity quantity estimator can estimate the residual electricity quantity value of the battery.

Description

technical field [0001] The present invention relates to a device for estimating the cycle life of a battery, in particular to a device which uses an adaptive algorithm to estimate the internal resistance of the battery from the input operating voltage and operating current, and then estimate the cycle life of the battery. , for real-time measurement and estimation, so it has the characteristics of continuous monitoring. This device is also applicable to lead-acid, nickel metal hydride and lithium-ion batteries. Background technique [0002] In terms of battery status monitoring function, it is divided into two parts: state of charge (SOC) estimation and cycle life (state of health, SOH) estimation, which are currently more frequently discussed topics, such as electric vehicle The battery pack management is in charge of a battery management system (Battery Management System, BMS), which is responsible for monitoring the battery status, having an overcharge / discharge protectio...

AI Technical Summary

Problems solved by technology

Due to the variable load when the electric vehicle motor is driven and the characteristics and differences of each unit battery (battery cell), the estimation error of the residual power of the battery can reach more than 5% to 10%. For the estimation of the cycle life, Because of this, it is the main reason why the cycle life estimation device, which is closely related to the timing of battery replacement by electric vehicle consumers, has not been commercialized

[0003] As for the existing battery cycle life estimation technology, it includes (1) the establishment of the battery cycle life function, and (2) the calculation of the battery parameters and system status of the function correspondence. The former technology must rely on a large number of laboratories and battery work measurements The data is analyzed and summarized. At present, there are no conclusive and clear conclusions and results in this research in the world. The accuracy of battery life judgment is most affected by this and is also the most controversial. The latter technology must be based on the requirements of the former technology. To measure or estimate unique parameters, the current international patent layout still focuses on lead-acid and nickel-metal hydride batteries, such as US No. 6456988 "Method for determining state-of-health using an intelligent system", No. 6885951 No. "Method and device for determining the state of function of an energy storage battery", No. 6469512 "System and method for determining battery state-of-health" and other known patents, there are few patents or improved technologies on the cycle life of lithium batteries

Images