The DoE didn’t free that tech to the public, the US government’s using licensing to actively prevent American companies from competing with the Chinese one they allowed a sublicense to be granted to (from your link):
> Forever Energy, a Bellevue, Wash., based company, is one of several U.S. companies that have been trying to get a license from the Department of Energy to make the batteries. Joanne Skievaski, Forever Energy's chief financial officer, has been trying to get hold of a license for more than a year and called the department's decision to allow foreign manufacturing "mind boggling."
> Forever Energy, a Bellevue, Wash., based company, is one of several U.S. companies that have been trying to get a license from the Department of Energy to make the batteries. Joanne Skievaski, Forever Energy's chief financial officer, has been trying to get hold of a license for more than a year and called the department's decision to allow foreign manufacturing "mind boggling."