A single-electrode thermoelectric parameter testing device for lithium-ion batteries

Abstract

The invention discloses a testing apparatus for a thermoelectric parameter of a single electrode of a lithium ion battery. The testing apparatus comprises an isothermal calorimeter, a measuring channel, a copper wire, a battery testing system, and an inverted-Y-shaped glass tube. The inverted-Y-shaped glass tube includes an upper end branch and a lower end arc branch; and the branches are communicated mutually. A circular-ball-shaped or ellipsoid-shaped protruding part is formed in the middle of the upper end branch. An injector is arranged at the opening of the upper end branch and is used for exhausting air to eliminate bubbles in an electrolyte and reduce the internal resistance. The two openings of the lower end arc branch are connected with upper openings of two polyfluortetraethylene pipes and the connecting parts are sealed. The testing apparatus with a simple structure is easy to operate. The thermoelectric performances of the electrode material as well as the safety performance of the battery can be evaluated; the measurement accuracy is improved; and the thermal design of the battery system can be optimized.

Description

technical field [0001] The invention relates to a testing device for thermoelectric parameters of a lithium-ion battery, and in particular provides a device for measuring thermal and electrical parameters during charging and discharging of a single electrode of a battery. Background technique [0002] Since its successful commercialization in 1990, lithium-ion batteries have developed into a secondary chemical power source with excellent performance. In recent years, the application of lithium-ion batteries in military and aerospace fields has gradually increased, and has gradually moved towards energy storage, electric vehicles and other fields. However, the performance of lithium-ion batteries is greatly affected by temperature. Excessively high temperature and uneven distribution will accelerate the decline of battery performance, reduce the service life of the battery, and may even cause thermal runaway and cause safety problems. The safety issue of lithium-ion batterie...

AI Technical Summary

Problems solved by technology

Using this experimental device to study the thermal effect of reversible reactions is aimed at the positive and negative single electrodes in the lithium-ion battery system, but there are still the following shortcomings: the two electrodes to be measured are located inside and outside the calorimeter, and the two electrodes The distance between the two electrodes is relatively long, and the plastic tube connecting the two electrodes is relatively long. Bubbles are easily generated in the electrolyte in the tube, and it is not easy to get rid of, resulting in an increase in internal resistance, which affects the accuracy of the test results; copper as lithium The current collector of the ion battery has poor compatibility with the electrolyte system. The electrolyte for lithium-ion batteries is highly corrosive. Once the copper is corroded or dissolved, the electrode material fixed on the copper mold will fall off, hindering the flow of electrons. transmission, which directly affects the performance and safety of Li-ion batteries

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