Impact of Sensor Positioning on Temperature Measurement Accuracy in Battery Modules

Monitoring temperatures in lithium-ion battery modules involves a trade-off between cost, complexity (number of sensors and connections) and accuracy of measurements, particularly regarding uncertainties in the estimation of temperature distribution. In this work, sensor placement throughout a battery module is studied considering such uncertainties. The proposed method combines finite element thermal simulations with matrix calculus to determine the optimal placement of temperature sensors in a lithium-ion battery module made up of 16 cells in a $4 \times 4$ cell arrangement. The module incorporates a perforated aluminum plate to hold the cells, providing uniform temperature distribution and a surface for accurate placement of temperature sensors. A detailed analysis is carried out to select the thickness of the aluminum plate. Subsequently, four different algorithms for sensor positioning are used to evaluate the estimation error when reconstructing the thermal map on the aluminum sheet by interpolating measured temperatures from the sampling points. This study provides an original approach for the implementation of thermal sensor placement, considering its potential application in battery thermal management systems.