Combine the banana, eggs, egg whites, oats, flour, sugar, baking powder, vanilla, cinnamon and salt in a blender. Puree until smooth. Stir in the chia seeds.
Heat a large skillet over medium-high heat. Brush with butter to coat. Add 1/4 cupfuls of the batter to the pan to form pancakes. Cook until bubbles break the surface of the pancakes and the undersides are golden brown, about 2 minutes. Flip with a spatula and cook about 1 minute more on the second side. Repeat with the remaining batter, adding more butter to the skillet as needed.
Serve the pancakes immediately. Top with berries and syrup.