A Review on Material Comparisons and Signal Acquisition of Wearable Electrocardiogram Monitoring Flexible Electrodes

Abstract

The development of wearable medical devices has placed greater demands on the selection and performance optimization of electrode materials. Traditional gel electrodes have low impedance and good conductivity, but they tend to cause skin irritation, dryness, and unstable signals during long-term monitoring. In contrast, flexible electrodes based on polymers and textile materials have advantages in biocompatibility, and are gradually emerging as potential alternatives for longterm electrocardiography(ECG) monitoring. This review summarizes common quantitative indicators used to evaluate the quality of ECG signals, including signal-to-noise ratio (SNR), kurtosis, and skewness. These indicators can reflect the stability and usability of the signals from different perspectives, providing a systematic reference for comparing electrode performance. This study did not offer specific experimental values but instead organised and summarised the evaluation methods based on existing literature to provide a theoretical basis for the subsequent structural design, material optimisation, and application expansion of flexible electrodes in wearable medical monitoring.