World’s largest battery maker announces major breakthrough in energy density

Re:World’s largest battery maker announces major breakthroug... by kpw94 on Friday April 21, 2023 @02:19AM (#35650331)

> Why does 500wh/kg make electric aircraft possible? 6x less than kerosene

Where did you read that kerosene is at 3000Wh/kg? My googling says 12,000Wh/kg

The tweet thread from TFA and its replies just says that for aircraft, weight impact is important. See https://twitter.com/__bdimitrov__/status/1298753593638440960:

"260 to 400 Wh/kg should lengthen flight time by 90.8% --- assuming that 100% of the drone weight is from the battery."

But going from 400 to 500 Wh/kg adds another 39% on top of that, so 2.6x longer total

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Re:World’s largest battery maker announces major breakthroug... by DrSAR on Friday April 21, 2023 @02:33AM (#35650421)

Yes. 12kWh/kg chemical energy for kerosene, a little more for avgas. But with a 25% efficiency you are only getting 3kWh out of a kg of fuel. Electric motors tend to have higher efficiency -- maybe up to 75% so you might nearly get 500Wh from a kg of battery.

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Re:World’s largest battery maker announces major breakthroug... by oblio on Friday April 21, 2023 @04:13AM (#35651027)

Electric motors are over 85%, some reaching 95%, from what I remember.

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