In this article, we demonstrate an all-solution-processed fabrication process that can render the surface of diverse 3D curved objects with electrochromic dynamic tunability, particularly in the mid-IR regime. With the rational material design of CNT bundles and PEDOT:PSS, a heterogeneous mixed ionic-electronic conductor was realized, allowing the PEDOT:PSS to be the outermost layer while remaining electrochemically active for tunable thermal emission. The solution-processed device shows an emissivity tunability of Δε = 0.195 with minimal decay even after 500 cycles. Heat transport calculations suggest that the electrochromic device can stabilize the temperature against fluctuations of 4.2 ℃ under mild convection ). Our work offers a robust pathway for scalable, solution-processed (ℎ = 3 𝑊/𝑚 devices, paving the way for future advanced thermal regulation and optical applications on complex 3D surfaces.