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Re:Electrified wingsuit from BMW reaches 186MPH on first flight by CrazyCatDog on Sunday November 15, 2020 @09:33AM (#25101474)
Lithium ion cannot output enough (low C) to make this feasible (yet). Much more likely using Li-Po cells, which are far more adept at emptying themselves at high load—but thermal runaway (eg insanely hot fires) is all too real with Li-Po, though less so today than say 6 years ago!
Re:Electrified wingsuit from BMW reaches 186MPH on first flight by nikda on Sunday November 15, 2020 @09:42AM (#25101549)
From Wikipedia: A lithium polymer battery, or more correctly lithium-ion polymer battery (abbreviated as LiPo, LIP, Li-poly, lithium-poly and others), is a rechargeable battery of lithium-ion technology using a polymer electrolyte instead of a liquid electrolyte.
Re:Electrified wingsuit from BMW reaches 186MPH on first flight by Robotbeat on Sunday November 15, 2020 @09:57AM (#25101646)
You’d be surprised. There are some high-C lithium ion cells, but they’re not as easily available as LiPo. If you need to dump your power over 4-10 minutes or longer at peak power, there are lithium ion cells available. Less than 4 minutes, LiPo is still better for now.
Re:Electrified wingsuit from BMW reaches 186MPH on first flight by CrazyCatDog on Sunday November 15, 2020 @11:23AM (#25102323)
Totally agree. My use case: 3 seconds max (launch), 3 seconds in-flight would be out of sight— total power on time between charges is well below one minute. I’m tempted to guess that this would be the most efficient way of converting electricity in wing suit applications as well.
Re:Electrified wingsuit from BMW reaches 186MPH on first flight by jononor on Sunday November 15, 2020 @04:10PM (#25104868)
That is more supercapacitor territory than batteries, especially if you do not require long-term energy storage (can accept relatively high self-discharge). The energy recovery systems in Formula 1 racing (KERS) are examples.
Re:Electrified wingsuit from BMW reaches 186MPH on first flight by Robotbeat on Sunday November 15, 2020 @06:03PM (#25105828)
What’s interesting is that in many cases, LiPos can equal the specific power of supercapacitors!