4 Things to Buy in Bulk—and 3 to Buy in Small Quantities

Lithium batteries, which are common in consumer electronics, have a great shelf life, so they're perfect for buying in large quantities. Stored at room temperature, or at about 70 degrees, they'll last 10 to 15 years (just keep them out of reach of children, since they can be dangerous if swallowed). Alkaline batteries—the ones shaped like cylinders—have a slightly shorter, but still very good, lifespan: about 5 to 10 years, in storage. One exception: Rechargeable batteries lose 1 percent of their deliverable energy every day, so only purchase those as needed.