Fifteen years of China's electric vehicle market: Findings from an EEMD analysis of sales data

Understanding the temporal evolution of electric vehicle (EV) markets is critical for designing effective diffusion pathways and supportive policy frameworks. This study conducts an Ensemble Empirical Mode Decomposition (EEMD) analysis of China's monthly EV sales data from January 2011 to December 2025, aiming to characterize market dynamics across multiple temporal scales and identify critical co-evolving events. The log-transformed sales series is decomposed into five stable intrinsic mode functions and one residual using EEMD, which are then reconstructed into short-, medium-, and long-term components through a period-based strategy. Variations in the reconstructed components are examined alongside representative policy, technology, and market events to interpret the historical context of China's EV market development. Results show that the long-term component maintains an upward trend, with its growth increment peaking around 2016 and moderating thereafter. The medium-term component exhibits periodic rises and falls, coinciding with industrial plans, technological breakthrough, and policy stringency. The short-term component captures seasonal fluctuations and local deviations that coincide with safety incidents, policy transitions, and the pandemic disruption. The findings suggest a multi-scale policy framework that emphasizes long-term support for market infrastructure, medium-term guidance on industrial and technological plans, and short-term measures to alleviate public concerns about EV safety and perceived policy uncertainty.