Lithium battery temperature dynamic monitoring method based on OFDR

Abstract

The invention discloses a lithium battery temperature dynamic monitoring method based on OFDR. The method comprises the steps that: signal light returned by a distributed optical fiber network and reference light are subjected to beat frequency interference, so that beat frequency interference signals are generated, sensing optical fibers in the distributed optical fiber network are transversely or longitudinally arranged on the upper surface, the lower surface and the side face of a lithium battery assembly or buried between single lithium battery packs. the beat frequency interference signals are acquired, so that a reference spectrum is obtained; the strain or temperature of the transverse initial positions of the sensing optical fibers is changed, and beat frequency interference signals are acquired, so that a measurement spectrum is obtained; the reference spectrum and the measurement spectrum are processed, so that a Rayleigh scattering spectrum of the measurement light and the reference light is obtained, calculation is performed to obtain a cross-correlation peak deviation value of each position, on the basis of a strain or temperature frequency shift coefficient, a final position-strain or position-temperature curve graph is obtained, and coordinates of a strain or temperature sudden change position in the curve graph are recorded; and a two-dimensional temperature field of a lithium battery is drawn in real time in equal proportion, and the temperature of the lithium battery is dynamically monitored.

Description

technical field [0001] The invention relates to the field of temperature detection, in particular to a method for dynamically monitoring the temperature of a lithium battery based on OFDR. Background technique [0002] With the rapid development of power battery technology, lithium batteries with high specific energy and high specific power are widely used in electric vehicles, toys, electric vehicles, electronic digital products, energy storage and other industries. Since lithium batteries are usually used as energy supply devices through individual battery packs connected in series and parallel to form battery panels, the difference in balance and ventilation between the monomers will cause inconsistent temperatures of lithium batteries at different locations under the same working load, which is not conducive to energy utilization. Efficient utilization and extension of battery life. Therefore, during long-term use, it is necessary to monitor the temperature of each part...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the problems of complex layout of traditional temperature sensors and easy external influence on measurement results, the present invention proposes an OFDR-based lithium battery temperature dynamic monitoring device and method for real-time monitoring of lithium battery temperature and over-temperature warning

Images