With 5P, five 4.8AH 21700 cell will give you 24AH, The Samsung 50S, which is 5AH and an amazing 25A discharge are on sale for 5.99 each. Yep, that's $420 in cells, but I wouldn't buy batteries from Uncle Ali.
https://www.18650batterystore.com/products/samsung-50s-21700-5000mah-25a-battery