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Why your outdoorsy friend suddenly has a gummy bear power bank

theverge.com

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

#61

Post by cenamus »

thegrim33 wrote: post #48
cenamus wrote: post #5

20Ah for 23 bucks? Seems like it's almost too good to be true. Wouldn't surprise me if it was just half that, would explain the price and weight.

Man it drives me crazy when people/products use Ah instead of Wh as a way to specify battery "capability". Without knowing more details about the battery, "20Ah" alone does not convey enough information to determine how long the battery could power a given load for. If I need to power a 100 watt lightbulb, will a 20Ah battery power it for an hour? 10 hours? 10 days? No way to know. Wh is the unit of stored energy, Wh…

Yeah, but pretty much every power bank uses lithium ion batteries (or used to, at least), so you use 3.7 average volts.

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

#63

Post by SR2Z »

mikestew wrote: post #59
thegrim33 wrote: post #48

Earlier quoted context omitted.

Man it drives me crazy when people/products use Ah instead of Wh as a way to specify battery "capability". Without knowing more details about the battery, "20Ah" alone does not convey enough information to determine how long the battery could power a given load for. If I need to power a 100 watt lightbulb, will a 20Ah battery power it for an hour? 10 hours? 10 days? No way to know. Wh is the unit of stored energy, Wh…

If your 100W light bulb is a USB bulb running at 5V (to make the math a bit easier), with 20 Ah you’ll get 100Wh, ergo it’ll run your bulb for a hour. You just need to specify the voltage. There are numerous online calculators to do this math for you. https://www.inchcalculator.com/ah-to-wh-calculator/ Watt-hours won’t save you, because we don’t know what voltage your bulb needs. Don’t assume it’s 120/240V.

I mean, I know what voltage/wattage my devices need. I have no idea what voltage the battery bank is going to offer.

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

#66

Post by pcmaffey »

dole wrote: post #62
XiphiasX wrote: post #40

Better question - why do you keep linking to websites that block visitor from reading the article?

Worse question: who’s got a hn frontpage/grease monkey/ai assisted subscription service to replace the main links with the archives?

And then open them in reader mode.

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

#67

Post by nerdsniper »

esperent wrote: post #58
thegrim33 wrote: post #48

Earlier quoted context omitted.

Man it drives me crazy when people/products use Ah instead of Wh as a way to specify battery "capability". Without knowing more details about the battery, "20Ah" alone does not convey enough information to determine how long the battery could power a given load for. If I need to power a 100 watt lightbulb, will a 20Ah battery power it for an hour? 10 hours? 10 days? No way to know. Wh is the unit of stored energy, Wh…

Isn't that 20Ah figure always relative to the internal voltage of the lithium batteries, 3.7v? At least that's what I always assumed.

10 years ago most of these battery packs were relative to the 5V output voltage, so they advertised lower amp-hours. That stopped making sense with fast charging at higher voltages so they restandardized on 3.7V.

But watt-hours would make infinitely more sense for all batteries.

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

#68

Post by hedora »

cenamus wrote: post #61
thegrim33 wrote: post #48

Earlier quoted context omitted.

Man it drives me crazy when people/products use Ah instead of Wh as a way to specify battery "capability". Without knowing more details about the battery, "20Ah" alone does not convey enough information to determine how long the battery could power a given load for. If I need to power a 100 watt lightbulb, will a 20Ah battery power it for an hour? 10 hours? 10 days? No way to know. Wh is the unit of stored energy, Wh…

Yeah, but pretty much every power bank uses lithium ion batteries (or used to, at least), so you use 3.7 average volts.

If you want to quadruple your amp hours without modifying the hardware, just treat 25% of the voltage gradient of each battery as your unit of measurement.

Alternatively, since this is USB-C, and we assume the marketing copy is honest, use the max voltage USB-C can deliver: 20v.

So, draw 20V from this device and measure the amp hours it outputs.

Wh is really the only sane way to go.

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

#69

Post by syedkarim »

cenamus wrote: post #61
thegrim33 wrote: post #48

Earlier quoted context omitted.

Man it drives me crazy when people/products use Ah instead of Wh as a way to specify battery "capability". Without knowing more details about the battery, "20Ah" alone does not convey enough information to determine how long the battery could power a given load for. If I need to power a 100 watt lightbulb, will a 20Ah battery power it for an hour? 10 hours? 10 days? No way to know. Wh is the unit of stored energy, Wh…

Yeah, but pretty much every power bank uses lithium ion batteries (or used to, at least), so you use 3.7 average volts.

Lithium NMC, which I think is the most common, is 3.7V. Lithium iron phosphate, which some power packs do use, has a nominal voltage of 3.2V.

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

#70

Post by ricardobeat »

phito wrote: post #34
cenamus wrote: post #5

20Ah for 23 bucks? Seems like it's almost too good to be true. Wouldn't surprise me if it was just half that, would explain the price and weight.

Also I doubt that Haribo has special light battery technology. Seems more likely that they lied on the capacity... Article doesn't test the capacity

This is a white-label product, they likely just used lighter plastic or a cheaper frame (cost savings? white color?) and accidentally made it attractive for hikers.

The weight difference to the Nitecore pack being mentioned is only ~15g.

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