A method and device for estimating battery open circuit voltage based on gas-hydrodynamic model

Abstract

The present invention provides a battery open-circuit voltage estimation method and device based on the gas-liquid dynamics model, including step 1 deriving the undetermined open-circuit voltage estimation equation based on the gas-liquid dynamics model, step 2 identifying and estimating equation parameters based on experimental data; step 3 According to the complete open circuit voltage estimation equation, the open circuit voltage estimation method is designed, and the estimated value of the open circuit voltage is calculated. The open circuit voltage estimation equation in the present invention includes the battery temperature, which does not need to be coupled with the battery temperature, which simplifies the open circuit voltage estimation process; the principle of gas dissolution / precipitation in the estimation equation is equivalent to the battery polarization effect, and better fits the open circuit voltage hysteresis battery Terminal voltage phenomenon; the estimation result of the estimation equation does not depend on the accuracy of the initial input value, and has excellent estimation robustness; it can more accurately describe the nonlinear process of battery charging and discharging, the analytical formula is simple, the parameter identification is easy, and the calculation amount is small , and reflects the influence of battery temperature characteristics on the open circuit voltage, which is convenient for engineering implementation.

Description

Technical field[0001]The present invention belongs to the field of battery management system, and more particularly to a battery opening voltage estimation method and apparatus based on a gas-liquid kinetic model.Background technique[0002]Petroleum is known as black gold, industry's blood, but oil resources will gradually move towards human beings. Traffic accounts for nearly half of the total oil consumption, and all countries in the world are trying to find energy in replace oil. Among them, vigorously develop electric vehicle technology is one of important options. However, during use, during use, due to the increase in discharge depth, the reduction in internal active substances, the increase of EIS membrane is increased, and the reversible capacity attenuation and changes in the ambient temperature have caused some important performance parameters in the battery. Change, and at present, the battery model is generally complicated, parameter change is unstable, causing the batter...

AI Technical Summary

Problems solved by technology

The intelligent algorithm needs to do a lot of calculations, which also makes it difficult for the model to realize real-time estimation on the vehicle MCU.

[0004] In summary, only relying on the existing battery model is far from meeting the requirements of practical applications. There is an urgent need for a model that can more accurately describe the nonlinear process of battery charge and discharge, reflect the battery temperature characteristics, have simple analytical formulas, and a small amount of calculation. Method and device for estimating open circuit voltage

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