Litre is an international scientific standard. It's spelling is not up for debate. Why don't you just change It's volume as well, and completely fuck up all scientific communication while your at it.
Hey, America. If you are going to ignorantly continue to use your obsolete and impractical system of measurement in spite of the rest of the would moving on to an objectively superior system generations ago, could you at least spell litres correctly when you fucking use the word?