A real-time evaluation method for lithium iron phosphate battery life loss

Abstract

The invention discloses a real-time evaluation method for life loss of a lithium iron phosphate battery and belongs to the field of electric power systems. The real-time evaluation method for life loss of the lithium iron phosphate battery comprises the steps of conducting a cycle life test on the lithium iron phosphate battery, determining the AH total amount of the lithium iron phosphate battery, determining the charge amount of the lithium iron phosphate battery in a certain period, determining the charge amount of the lithium iron phosphate battery in a certain period, and determining thelife loss of the lithium iron phosphate battery. The evaluation method for the life loss of a lithium iron phosphate battery does not need to get a charging current I changing curve and an operating environment temperature T curve of the lithium iron phosphate battery in the whole cycle period in one time; while considering the influences of the charging rate and the ambient temperature, life lossof the lithium iron phosphate battery can be calculated online according to the charging and discharging processes of the lithium iron phosphate battery. The method is clear in the basic structure and fast in the calculation speed, which satisfies the real-time requirement for the evaluation of the life loss of the lithium iron phosphate battery.

Description

technical field [0001] The invention belongs to the field of power systems, and in particular relates to a real-time lithium iron phosphate battery life evaluation method. Background technique [0002] Due to the inherent characteristics of natural resources, renewable resource power generation represented by wind power and photovoltaic power generation generally has random fluctuations and unpredictable characteristics. These two characteristics have brought great challenges to the grid integration of renewable energy power generation. The application of energy storage technology can effectively alleviate the random fluctuation and unpredictability of renewable resource power generation, so as to realize the large-scale grid connection of renewable resource power generation, and replace some conventional generating units to bear a certain basic load. [0003] Energy storage technologies include pumped water storage, compressed air energy storage and various battery energy ...

AI Technical Summary

Problems solved by technology

The loss of lithium iron phosphate battery life is related to factors such as charge and discharge rate, charge and discharge times, charge and discharge depth, ambient temperature, electrolyte concentration, electrolyte concentration, high frequency diffusion, etc. The establishment of a life prediction model that considers all relevant factors is Very difficult, and the calculation speed cannot meet the requirements of real-time evaluation of battery life

[0005] At present, the battery life assessment based on the physicochemical aging model is the most complex and complete method, but the model requires a large amount of data information, including detailed geometric data (thickness and number of pores of the electrode), volume and concentration of the electrolyte, etc. , this parameter can be easily obtained in the laboratory, but it cannot be obtained during the normal use of the battery

Event-oriented aging model has difficulty in event definition and classification

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