Another plus and the reason that I've replaced all the flouro fittings that were in my sheds and loft is that led fixtures tend to be a lot shorter (and in my case made of plastic). The old fixtures in the sheds were obscuring the shelves and the the ones in the loft were in danger of being broken by my head as the head height is a bit tight.LED battens can be and often are brighter than fluorescent battens of the same electrical power, As Sunray has pointed out it may that two LED battens will be needed to achieve the required illumination but the two together will take about the same electrical power as the single fluorescent batten.
https://www.lyco.co.uk/force-50w-daylight-led-batten-5ft.html being just one example.
Best to avoid low cost battens as they can be overdriven LED elements and thus short lived.