watt-hour
noun
: a unit of work or energy equivalent to the power of one watt operating for one hour
Examples of watt-hour in a Sentence
Recent Examples on the Web
In comparison, radioactive batteries generate only about 2 watt-hours per kilogram, which the Rads to Watts Program aims to address.
—
Ameya Paleja, Interesting Engineering, 9 Apr. 2026
Southwest says spare batteries and power banks must be carried onboard, with terminals protected against short circuits and capacity capped at 100 watt-hours.
—Aidin Vaziri, San Francisco Chronicle, 8 Apr. 2026
In the study, the team created lithium metal pouch cells that achieved an energy density of 317 watt-hours per pound (Wh/lb) at room temperature.
—New Atlas, 7 Apr. 2026
Specifically, look for the number of watt-hours (Wh).
—Matthew Korfhage, Wired News, 3 Apr. 2026
Fletcher said Sion Power’s lithium-metal cells are engineered to deliver energy densities exceeding 500 watt-hour per kilogram, compared with approximately 300-350 Wh/kg for today’s most advanced lithium-ion technology.
—Michael Wayland, CNBC, 24 Mar. 2026
Of LuSEE-Night’s launch mass of 108 kg, about 38 kg is a lithium-ion battery pack with a capacity of 7,160 watt-hours, mostly to generate heat.
—IEEE Spectrum, 20 Jan. 2026
With 16,896 usable watt-hours of energy—enough to run the air-conditioning for up to 14 hours on battery power alone—the system supports everything from the convection oven to the vehicle’s computer systems, Fusion audio, and 24-inch LED TV.
—Robb Report Studio, Robb Report, 26 Nov. 2025
The policy also restricts the size of lithium batteries eligible for transportation on Southwest flights, to 300 watt-hours or less.
—Zach Wichter, USA Today, 15 Sep. 2025
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Ameya Paleja, Interesting Engineering, 9 Apr. 2026
Southwest says spare batteries and power banks must be carried onboard, with terminals protected against short circuits and capacity capped at 100 watt-hours.
—Aidin Vaziri, San Francisco Chronicle, 8 Apr. 2026
In the study, the team created lithium metal pouch cells that achieved an energy density of 317 watt-hours per pound (Wh/lb) at room temperature.
—New Atlas, 7 Apr. 2026
Specifically, look for the number of watt-hours (Wh).
—Matthew Korfhage, Wired News, 3 Apr. 2026
Fletcher said Sion Power’s lithium-metal cells are engineered to deliver energy densities exceeding 500 watt-hour per kilogram, compared with approximately 300-350 Wh/kg for today’s most advanced lithium-ion technology.
—Michael Wayland, CNBC, 24 Mar. 2026
Of LuSEE-Night’s launch mass of 108 kg, about 38 kg is a lithium-ion battery pack with a capacity of 7,160 watt-hours, mostly to generate heat.
—IEEE Spectrum, 20 Jan. 2026
With 16,896 usable watt-hours of energy—enough to run the air-conditioning for up to 14 hours on battery power alone—the system supports everything from the convection oven to the vehicle’s computer systems, Fusion audio, and 24-inch LED TV.
—Robb Report Studio, Robb Report, 26 Nov. 2025
The policy also restricts the size of lithium batteries eligible for transportation on Southwest flights, to 300 watt-hours or less.
—Zach Wichter, USA Today, 15 Sep. 2025
Cite this Entry
“Watt-hour.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/watt-hour. Accessed 20 Apr. 2026.
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