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258 points arnon | 2 comments | | HN request time: 0.001s | source

https://archive.ph/1G2Ut
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mbesto ◴[] No.45327428[source]
This is a very poorly researched article. A few things worth considering:

- 20,000 mAh is the rated capacity. Anyone who has tested 18650 batteries (which are the cells typically used in these battery packs) knows the rated capacity != tested capacity.

- Watthours is more important than amp hours

- Tested watt hours as typical loads is more important than amp hours

- It's very normal to see tested capacity to be roughly 70~80% of rated capacity.

- This commenter said they got "At 18W average, I pulled out 55.4Wh" on the Haribo [0]

- The generally considered "gold standard" for ultra light batteries in this range is the Nitecore NB20000 Gen 3, which regularly tests around 56 Wh.

So yes the conclusion is correct - you get roughly the same amount of capacity for a typical load (18W phone) for a cheaper price and slightly less weight. Very curious what battery cells the Haribo uses.

[0] - https://old.reddit.com/r/Ultralight/comments/1li5rxw/20000ma...

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coin ◴[] No.45327839[source]
> Watthours is more important than amp hours

I'd go a step further and say that amp hours is meaning less since voltage is not specified. The only valid battery capacity unit of measure is watt hours. While most battery packs use a single 3.7 lithium ion battery, Apple's first gen MagSafe battery pack used two internal batteries in series, throwing off everyone's amp hours only comparison.

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nwallin ◴[] No.45328092[source]
> The only valid battery capacity unit of measure is watt hours.

I would also accept Joules. But yes, the unit should be a unit of energy.

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1. macrocosmos ◴[] No.45328143[source]
We could also talk about lb•AU (pound Astronomical Units), but generally it's best to stick to what's standard so readers don't need to do conversions. Watt hours is great.
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2. fy20 ◴[] No.45329241[source]
It's not terrible... The iPhone 17 has a battery capacity of 63 nano lb·AU. Around 16 million would equal 1 lb·AU.

Another fun one would be milli hundredweight leauge (mcwt·lg). Both hundredweight and league have multiple accepted definitions to make it more "fun". But the range maps quite nicely to everyday things:

AA battery - Around 5 mcwt·lg

Phone battery - Around 20 mcwt·lg

Laptop battery - Around 200 mcwt·lg

Car 12v battery - Around 1,000 mcwt·lg

EV battery - Around 100,000 mcwt·lg