ProsserP, you bring up another interesting point from the past.
About 1-2 yrs ago, I was certain i heard someone in an EFL CC mention they were replacing some fuel cell forklifts with lithium. I hunted through transcripts and couldn't find it. I emailed Jason and he said he would check on it. I never got an answer. FYI - He would/should have known the answer to that question.