Shower thought: long term storage of charcoal briquettes?

The wfe and I are, hopefully, closing on a house in a few weeks and a few minutes ago in the shower, I thought it might be worth trying to store charcoal briquettes in some 5-gallon buckets with gamma lids to augment propane and wood for emergency cooking. The longest I've ever kept charcoal briquettes is about a year and they worked fine. A cursory Google search wasn't very fruitful. Have any of you tried storing them for several years in the past? I imagine to some extent they may become brittle over time, I'm assuming the chemicals they are treated with would probably have some sort of issues over varying lengths of time, and moisture is obviously going to be the enemy but a sealed bucket would give them at least a few years I would suspect. I know lump charcoal would store much better/longer but I can't say that I've ever actually seen it in a store before.