A Hybrid Modeling Method for Decommissioned Power Lithium Batteries

Abstract

The invention discloses a hybrid modeling method for decommissioned power lithium batteries, which belongs to the application field of power lithium batteries. The method includes establishing the first-order equivalent circuit model of the decommissioned power lithium battery, and obtaining model parameters; using the partial least square method to perform secondary fitting on the error formed by the first-order equivalent circuit model, and establishing the deviation compensation of the decommissioned power lithium battery Model; combine the first-order equivalent circuit model and the deviation compensation model to establish a hybrid model for decommissioned power lithium batteries. In the present invention, the decommissioned battery whose external characteristics have changed to a certain extent, describes the basic external characteristics of the battery through a first-order equivalent circuit model, and establishes a deviation compensation model based on partial least squares, which can effectively improve the modeling accuracy of decommissioned power batteries and facilitate The follow-up battery management system realizes accurate estimation of battery state parameters and efficient energy management of battery packs, which is helpful for cascade utilization of decommissioned power batteries.

Description

Technical field [0001] The present invention relates to the field of power lithium battery applications, and more particularly to a mixed modeling method for retiring dynamic lithium batteries. Background technique [0002] Lithium batteries have become the most important energy storage components of current new energy vehicles. However, with the daily use of new energy vehicles, the power lithium battery will inevitably gradually age. The lithium battery retired from the vehicle still has the potential value of continued use in an occasion of the low performance requirements, that is, the retired battery still has the value of the ladder. The battery model is an important foundation for system energy management in the ladder, and the battery core status parameter (STATEOF CHARGE, SOC), a health status, the acquisition of the State of Health, and SOH, requires a precise battery model. . [0003] Compared with the new battery, the retired lithium battery has passed the new energy ...

AI Technical Summary

Problems solved by technology

However, historical data is missing during the initial use of lithium batteries, which makes it impossible to directly use a large amount of data to establish a data-driven battery model

The traditional empirical model only describes the external characteristics of the battery through mathematical functions, which obviously cannot meet the complex needs of decommissioned battery modeling

The electrochemical model has a large amount of calculation, many parameters and difficult to obtain

Commonly used equivalent circuit models generally need to increase the number of parallel resistor-capacitor networks in order to improve modeling accuracy. When applied to decommissioned power lithium batteries, it is likely to cause problems such as complex model structure and difficulty in online parameter identification.

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