This is not correct. Do you have a source? The cells definitely prefer to be stored below 50%. For daily cycling, keeping it right around the midpoint is advised.
Only in swedish and only as a short news-piece.
Batterimyterna som fr dina prylar - DN.SE
"Battery myths that destroy your gadgets" is the headline freely translated to english.
I have no idea if this is correct or not, but the source quoted in the article seemed good.