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A comment on Why your outdoorsy friend suddenly has a gummy bear power bank. Parent comment

Re:Why your outdoorsy friend suddenly has a gummy bear power... by bmicraft on Monday September 22, 2025 @03:39PM (#45338446)
That's wrong, if they only specifiy Ah, then they usually imply cell voltage (3.7V avg.) and not the 5V you're drawing over USB.

Even if you assume you're charging a phone with that, you first need to subtract 25-40% total losses. And then consider that phone batteries are LiHV with 3.85-3.9V nowadays.

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Re:Why your outdoorsy friend suddenly has a gummy bear power... by mattmaroon on Thursday September 25, 2025 @12:14PM (#45374717)
That’s a fair point. I guess I’m thinking of 12v world, like I experience in my RVs and food trucks, where the battery powers everything and it’s all 12v.
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