OpenNeuro: 17 EEG datasets including 547 subjects.https://openneuro.org/
PhysioNet:Neuroelectric and Myoelectric Databases.https://physionet.org/about/database/#neuro
MNI Open iEEG Atlas: 1772 channels with normal brain activity from 106 subjects.https://mni-open-ieegatlas.research.mcgill.ca/
TUH EEG:A dataset consist of 20000 clinial EEGs.https://www.isip.piconepress.com/projects/tuh_eeg/index.shtml
European Epilepsy Database: The database contains EEG datasets from ~250 patients with epilepsy.http://epilepsy-database.eu/
DEAP dataset: A dataset for emotion analysis using EEG, physiological and video signals.http://www.eecs.qmul.ac.uk/mmv/datasets/deap/readme.html
EEG data available for free:https://sccn.ucsd.edu/~arno/fam2data/publicly_available_EEG_data.html