Some oil diffusers are cordless and designed for portability, running on batteries (often AA cells). That lets you move them from room to room without needing an outlet.
Duration depends on the product format and specific refill. Typical lifespans range from about 2 weeks up to around 150 days, depending on the refill or sachet.
Many oil diffusers offer adjustable burst intervals or fragrance levels—for example, timed bursts every 9, 18, or 36 minutes or selectable fragrance intensity. Some units also include an initial boost plus timed run/standby cycles.