I have a 10-year-old Princeton Tec headlamp that is regulated so can safely use lithium batteries. A set of batteries lasts for months even though I also use the headlamp a lot around home (great for hands-free cleaning or repairs under the kitchen sink, for example). While it's a bit heavier than I'd like, I've tried a few lightweight ones (such as the Petzl e+Lite) and found that they don't provide enough light for safe night hiking.

For a week or longer trip, I put in a fresh set of batteries and don't need to take spares.

I frankly have not felt the need to check the market recently to see if these headlamps are still being made--the one I have is doing just fine, thank you.