This paper investigates the cosmological implications of exponential quintessence, a string-motivated dark energy model, using the latest cosmological data. The authors perform a detailed cosmological analysis of exponential quintessence with a potential given by \( V = V_0 e^{-\lambda \phi} \), allowing for non-zero spatial curvature. They first gain physical intuition by analyzing the dynamical system governing the evolution of such a scenario. The model is then tested using a combination of *Planck* CMB data, DESI BAO data, and recent supernovae datasets. The results indicate a preference for nonzero values of the parameter \(\lambda\), with marginalized means and limits at 68% confidence level (C.L.) being \( \lambda = 0.48^{+0.28}_{-0.21} \), \( 0.68^{+0.31}_{-0.20} \), and \( 0.77^{+0.18}_{-0.15} \) when combining CMB+DESI with Pantheon+, Union3, and DES-Y5 supernovae datasets, respectively. The study finds no significant hint for spatial curvature. The implications of these findings for exponential quintessence and dark energy in string theory are discussed.This paper investigates the cosmological implications of exponential quintessence, a string-motivated dark energy model, using the latest cosmological data. The authors perform a detailed cosmological analysis of exponential quintessence with a potential given by \( V = V_0 e^{-\lambda \phi} \), allowing for non-zero spatial curvature. They first gain physical intuition by analyzing the dynamical system governing the evolution of such a scenario. The model is then tested using a combination of *Planck* CMB data, DESI BAO data, and recent supernovae datasets. The results indicate a preference for nonzero values of the parameter \(\lambda\), with marginalized means and limits at 68% confidence level (C.L.) being \( \lambda = 0.48^{+0.28}_{-0.21} \), \( 0.68^{+0.31}_{-0.20} \), and \( 0.77^{+0.18}_{-0.15} \) when combining CMB+DESI with Pantheon+, Union3, and DES-Y5 supernovae datasets, respectively. The study finds no significant hint for spatial curvature. The implications of these findings for exponential quintessence and dark energy in string theory are discussed.