Detection method for quantitatively detecting electrolyte distribution in battery and application

Abstract

The invention provides a detection method for quantitatively detecting electrolyte distribution in a battery and application. The detection method comprises the following steps: performing an electrochemical impedance test or a voltage test on a sample battery to obtain a corresponding test curve; performing ICP test on the pole piece of the sample battery to obtain an electrolyte content distribution diagram in the pole piece, and establishing a mapping relation between the electrolyte content distribution diagram and the test curve; performing an electrochemical impedance test or a voltage test on the to-be-tested battery, and inferring the electrolyte content distribution state in the to-be-tested battery pole piece by combining a test result with the mapping relation. According to the method, the mapping relation between the electrochemical impedance test or the voltage test and the ICP method fixed-point quantitative detection is obtained, so that the distribution condition of the electrolyte in the battery can be quantitatively detected on a large scale, the operation is simple, the data result is reliable, and the method plays a promoting role in optimizing the production process of the battery; and a theoretical basis is provided for predicting the safety and the circularity of the battery.

Description

technical field [0001] The invention belongs to the technical field of battery detection, and relates to a detection method and application for quantitative detection of electrolyte distribution inside a battery. Background technique [0002] Electrolyte solution is an important part of lithium-ion batteries and is the + A bridge for transmission between positive and negative electrodes. The electrolyte of lithium-ion batteries is generally a non-aqueous electrolyte, composed of organic solvents (such as: PC, EC and DMC, etc.) and conductive salts (such as LiPF 6 、LiBF 4 and LiClO 4 etc.) composition. At present, there are still many problems in the rapid development of lithium-ion batteries, such as the safety performance, cycle performance and electrochemical performance of the battery cell. These problems are closely related to the distribution of the electrolyte in the battery. The uniformity of the electrolyte distribution in the lithium-ion battery is one of the k...

AI Technical Summary

Problems solved by technology

[0010] The current methods of characterizing the infiltration state of the electrolyte in the battery have their own advantages and disadvantages, but it is difficult to monitor the infiltration of the electrolyte under different conditions.

The spectroscopic method can qualitatively detect the distribution of the electrolyte inside the cell without destroying the battery cell. Fixed-point quantitative measurement of the distribution of

At the same time, the spectroscopic method also involves the introduction of some isotopes, fluorescent substances or colored substances. The introduction of these substances may affect the fluidity, wettability and other properties of the electrolyte, so that it cannot truly and effectively reflect the impact of the electrolyte. Wetting of the cell

[0011] Mass spectrometry can quantitatively analyze the distribution of the electrolyte, but it needs to disassemble the battery cells, which is cumbersome and difficult to achieve mass detection of the cells

The electrochemical method is a simpler and more efficient method to quantitatively analyze the distribution of the electrolyte in the battery, but it is also difficult to achieve fixed-point quantitative measurement of the distribution of the electrolyte in the battery.

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