Why your outdoorsy friend suddenly has a gummy bear power bank • Hacker News Board

Re: Why your outdoorsy friend suddenly has a gummy bear power bank

#241

Post by masklinn » Mon, Sep 22, 2025, 5:14 AM UTC

mbesto wrote: post #124

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 roug…

> Watthours is more important than amp hours

Although that is completely true, pretty much all discussion, speccing, and marketing of batteries and power banks is done in Ah. So the article working in that unit is logical and consistent.

Re: Why your outdoorsy friend suddenly has a gummy bear power bank

#242

Post by harrall » Mon, Sep 22, 2025, 5:46 AM UTC

mbesto wrote: post #124

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 roug…

A lot of battery packs do not use 18650s but rather pouches, which are a lot smaller at the cost of some stability.

Re: Why your outdoorsy friend suddenly has a gummy bear power bank

#243

Post by kybernetyk » Mon, Sep 22, 2025, 5:49 AM UTC

tedggh wrote: post #18

I traveled ultralight until I got into landscape photography. Those tele zooms are heavy AF. I got bigger quads and biceps.

Try out Micro Four Thirds. I have an OM-5 as my secondary camera and it's great for hiking, etc.

Re: Why your outdoorsy friend suddenly has a gummy bear power bank

#244

Post by vasco » Mon, Sep 22, 2025, 5:58 AM UTC

JohnFen wrote: post #9

Zanni wrote: post #2

Why your [ultra-light hiker] friend suddenly has [the world's lightest] power bank. I remember Colin Fletcher, years ago, writing in The Complete Walker about trimming the borders off his paper maps to save weight, which seemed like an insane over-optimization to me. But then, I'm not an ultralight hiker. I am impressed folks are getting their loads down to 10 pounds though.

That insane over-optimization is how folks are getting down to (and below) 10 pounds. I'm not even remotely an ultralight backpacker, but I do count ounces (no matter what your weight limit is, you can't escape making tradeoffs to stay within it). Your hiking load is a great example of how quickly apparently insignificant quantities can add up. Saving fractions of an ounce multiple times gets you large savings far mo…

Better not forget to take a shit in the morning ever, or all your efforts are wasted.

Re: Why your outdoorsy friend suddenly has a gummy bear power bank

#245

Post by stefanka » Mon, Sep 22, 2025, 6:05 AM UTC

I’m kind of disappointed that the earbuds mentioned in the text aren’t shaped like gummy bears (and the power bank not like a pack thereof)

Re: Why your outdoorsy friend suddenly has a gummy bear power bank

#246

Post by n2d4 » Mon, Sep 22, 2025, 6:30 AM UTC

mbesto wrote: post #217

tredre3 wrote: post #212

Earlier quoted context omitted.

I don't think this power bank uses 18650. You could fit 3 18650 in it, but the highest capacity 18650 out there is less than 15Wh and this advertises 77Wh. Even the tested capacity of 55Wh is higher than the before-loss 18650 capacity you could fit in it. > This is a very poorly researched article So, yeah, pot, kettle, all that.

I think you're right, however, 18650 batteries do carry, on average, more energy density per volume and weight. > but the highest capacity 18650 out there is less than 15Wh and this advertises 77Wh. 10x 2000 mAh 18650 batteries in parallel gives you 20 Ah @ 3.7V. > So, yeah, pot, kettle, all that. Totally unnecessary comment but thanks.

> Totally unnecessary comment but thanks.

It's not more unnecessary than your comment about the OP article being poorly researched. If the conclusions are true, even if they didn't do the measurements themselves, I find it quite excusable to skip past the detailed specs of the battery.

Re: Why your outdoorsy friend suddenly has a gummy bear power bank

#247

Post by eru » Mon, Sep 22, 2025, 6:38 AM UTC

prawn wrote: post #186

eru wrote: post #171

Earlier quoted context omitted.

If you are bringing your phone anyway, might as well use that for your mapping needs? You can have a backup paper map inked on your skin.

I have previously wondered about printed handkerchiefs and bandanas that functioned as backup maps. Invest in my kickstarter!

That's a great idea!

(Mildly amusing, I first read 'printed handkerchiefs and bananas'. Like paint your map on the skin of your apple, or the shell of your hardboiled eggs.)

Re: Why your outdoorsy friend suddenly has a gummy bear power bank

#248

Post by globular-toast » Mon, Sep 22, 2025, 6:42 AM UTC

bobsmooth wrote: post #166

exabrial wrote: post #80

> Ultralight culture seems a little nuts to the uninitiated. I prefer "Durable, but as light as possible", not the other way around. Most ultralight gear breaks after a few uses or when it is mishandled in anything-less-than-perfect conditions, which, happens a lot outside.

I think people that do long distance hiking are a little nuts but to each their own.

Can confirm there are not many mundanes doing it. It's a bit like how hacker culture used to be before the money.

Re: Why your outdoorsy friend suddenly has a gummy bear power bank

#249

Post by beAbU » Mon, Sep 22, 2025, 6:43 AM UTC

nwallin wrote: post #170

coin wrote: post #159

Earlier quoted context omitted.

> 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.

> 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.

You are probably making a joke, but just in case and for those that don't know, a joule _is_ a watt hour.

1 joule is 1 watt-second to be precise. So 1Wh is 3600 joules.

Re: Why your outdoorsy friend suddenly has a gummy bear power bank

#250

Post by beAbU » Mon, Sep 22, 2025, 6:46 AM UTC

masklinn wrote: post #241

mbesto wrote: post #124

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 roug…

> Watthours is more important than amp hours Although that is completely true, pretty much all discussion, speccing, and marketing of batteries and power banks is done in Ah. So the article working in that unit is logical and consistent.

The bit that annoys me always (and what makes Ah a meaningless measurement for power banks) is whether the amp-hours rating is just the internal batteries' spec summed together, or is it as measured at the 5V outlet? Huge difference!