Method for detecting residual mass of electrolyte

Abstract

The invention discloses a method for detecting the residual mass of an electrolyte, which comprises the following steps: taking a standard sample with known specific heat capacity as a first sample and a reference sample with the same electrolyte ratio as a to-be-detected battery as a second sample, heating the first sample and the second sample to obtain the specific heat capacity of the second sample, and carrying out phase change on the second sample to obtain the phase change latent heat of the second sample; cooling the to-be-tested battery and the second sample to the same first temperature until the to-be-tested battery and the second sample are frozen into a solid state, then heating the materials to the same second temperature until the to-be-tested battery and the second sample are changed into a liquid state, and calculating the mass difference delta m between the to-be-tested battery and the second sample according to the difference between the heat capacities absorbed by the to-be-tested battery and the second sample; and finally, obtaining the electrolyte residual mass of the battery to be measured. According to the method, the electrolyte residual mass of the lithiumion battery can be detected instead of a certain substance, the electrolyte residual mass of the battery can be detected without disassembling the original structure of the battery, and the whole life process of the battery can be subjected to in-situ detection.

Description

technical field [0001] The invention relates to the technical field of lithium-ion batteries, in particular to a method for detecting the residual mass of an electrolyte. Background technique [0002] A lithium-ion battery is a rechargeable battery that primarily relies on the movement of lithium ions between the positive and negative electrodes to function. Electrolyte is the "blood" of lithium-ion batteries. It plays the role of conducting ions between the positive and negative electrodes in the battery. It is the guarantee for lithium-ion batteries to obtain excellent performance such as high voltage and high power. The electrolyte is generally composed of organic solvents, electrolyte lithium salts, and additives, and is prepared in a certain proportion under certain conditions. [0003] Drying out of the electrolyte of lithium-ion batteries is a common aging mode. As the amount of electrolyte decreases, the available lithium ions in the electrolyte decrease, resulting ...

AI Technical Summary

Problems solved by technology

[0004] Currently commonly used electrolyte detection methods are generally very limited, for example: the detection of free acid, the detection of lithium element content is limited to a certain substance in the electrolyte and the detection at a certain stage, and in the traditional way due to The battery needs to be disassembled for detection, so it is very difficult to quantitatively measure the amount of remaining electrolyte without disassembling the battery

However, in situ testing of batteries throughout their lifetime is not possible due to the need to disassemble the batteries resulting in irrecoverable battery failure

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