Estimation circuit for soc and soh of battery

An estimation circuit for SOC and SOH of battery includes:

• a control circuit for receiving a reset signal, a voltage signal and a current signal, the control circuit determines the voltage level of an electrical-capacity calculation reset signal, an estimation optional signal, an over voltage enable signal, a normal state enable signal, a low voltage enable signal and a current-estimated reset signal outputted from the control circuit according to the reset signal, the voltage signal and the current signal;
• a current estimation circuit having a current modification circuit and a Coulomb integral circuit, wherein the current modification circuit receives the current signal and multiplies the current signal by a modification parameter and outputs a modified current signal, the Coulomb integral circuit receives the modified current signal and the current-estimated reset signal of the control signal and integrates the modified current signal for outputting an estimating electrical-capacity value;
• an open-circuit voltage detection circuit for receiving the voltage signal, wherein the open-circuit voltage detection circuit outputs an initial electrical-capacity value via the voltage signal;
• an optional multiplexer for receiving the estimation optional signal of the control circuit, the estimating electrical-capacity value of the current estimation circuit and the initial electrical-capacity value of the open-circuit voltage detection circuit, the optional multiplexer outputs an estimating electrical-capacity signal and determines the estimating electrical-capacity signal equal to the estimating electrical-capacity value or the initial electrical-capacity value according to the estimation optional signal;
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• an electrical-capacity calculation circuit having an over voltage register, a normal state register and a low voltage register, wherein the over voltage register receives the estimating electrical-capacity signal, the electrical-capacity calculation reset signal and the over voltage enable signal, the normal state register receives the estimating electrical-capacity signal, the electrical-capacity calculation reset signal and the normal state enable signal, the low voltage register receives the estimating electrical-capacity signal, the electrical-capacity calculation reset signal and the low voltage enable signal, wherein the over voltage register, the normal state register and the low voltage register determine whether to store the estimating electrical-capacity signal is controlled by the over voltage enable signal, the normal state enable signal and the low voltage enable signal respectively, wherein the difference value between a signal stored in the normal state register and a signal stored in the low voltage register is a battery electrical-capacity remaining signal, and the difference value between a signal stored in the over voltage register and the signal stored in the low voltage register is a battery state of health signal.