Yeah, mine isn't great either. It's rated at 13 lux, which doesn't mean much actually, but it's not very useful outside when it's dark. I bought this one instead: Smart BL 185 700L Front Light | Chain Reaction Cycles

It has its own battery so I can use it even when I ride my ebike without the battery (which I do every day, for sports).
Also, the reviews in the link above say it's plenty powerful.