Battery internal resistance test method based on year-on-year multi-rate mixed pulse power characteristics

Abstract

The invention provides a battery internal resistance test method based on year-on-year multi-rate mixed pulse power characteristics, which at least comprises the following steps of: (1) discharging the electric quantity of a battery, standing for a period of time, fully charging, and fully standing; (2) starting from 100% of SOC, testing by using a discharge pulse and a regeneration pulse with the same proportion; (3) carrying out multi-rate charge and discharge test; (4) discharging the battery at constant current until the SOC is reduced by x%; (5) repeating the steps (2)-(4) and collecting corresponding voltage data of the battery under different charge-discharge rates and different SOCs (State Of Charge); (6) after the final SOC is tested, discharging the battery to the SOC of 0%; and (7) according to the acquired response voltage data, calculating the polarization internal resistance and the ohm internal resistance of the battery under different charge and discharge rates and different SOCs. According to the invention, a multi-rate mixed pulse charge and discharge internal resistance test experiment is realized, and the method is suitable for a large-range battery SOC test while short test time, few test times and high precision are ensured.

Description

technical field [0001] The invention relates to the technical field of lithium-ion batteries, and more specifically, relates to a method for testing the ohmic internal resistance and polarization internal resistance of a lithium-ion battery. Background technique [0002] Lithium-ion batteries have been widely used in many fields such as electronic products, electric vehicles, and power storage. In order to ensure that the batteries are in good working condition, the battery characteristics of lithium-ion batteries should be focused. [0003] Internal resistance is a particularly important parameter in the characteristics of lithium-ion batteries. It can measure the difficulty of electrons and lithium ions in lithium-ion batteries being transported inside the battery, and can directly reflect the health status and service life of lithium-ion batteries. A decisive parameter for the irreversible heating of batteries. Therefore, it is of great practical significance to accurate...

AI Technical Summary

Problems solved by technology

[0005] (1) Due to the battery itself, when charging at a high rate, there is still a capacity loss in the recharging of the battery; therefore, when testing under the conditions of multiple rates and SOC, there is still a capacity loss;

[0006] (2) This method cannot measure the internal resistance of a battery with an SOC of 100%, and the SOC decreases by 10% each time, which cannot meet the rich testing needs of customers

[0007] (3) Since the current ratio of the discharge pulse and the regeneration pulse are inconsistent, it is necessary to separate the two processes when testing the internal resistance of charge and discharge, which will still cause a waste of time

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