Stormlight Archives is one long series that will be split in two. The first five books will be about the characters we're currently reading about, whereas the latter five will be a sequel series of sorts (from what I understood). In that sense the series will be long, but you could probably read the first five as a stand-alone. From the Wiki Page:

Ten books are planned in the series, broken down into two sets of five books each. Sanderson describes the planned story arc of the second set of five book as a "sequel" to the first set, with some appearances of characters from the first set.