crazy power bank

[jmelson]

OK, today I got a spam for a 50 A-Hr solar power bank.  They didn't give a reference for size, but I'm guessing the thing MIGHT be the size of a cell phone.  It had a hole at one end and a carabiner hooked on the hole.  But, carabiners come in all sizes.  it had a soler panel that covered most of one side of the thing.

Well, how many batteries do you need to put in the thing to get 50 A-Hr capacity?  Sounds like a lot, even if just 3.7 V terminal voltage.  How long does it take a 3 x 5" solar cell to charge a 50 A-Hr battery?  I'd guess about a WEEK!

OK, here's one that's 600 A-Hr!
< https://www.walmart.com/ip/Waterproof-600000mAh-Dual-USB-Portable-Solar-Charger-Solar-Power-Bank-For-Phone-Red/361608483?wmlspartner=wlpa&selectedSellerId=5705&adid=22222222227246824345&wl0=&wl1=g&wl2=c&wl3=290728191968&wl4=pla-495014917113&wl5=9060158&wl6=&wl7=&wl8=&wl9=pla&wl10=114441947&wl11=online&wl12=361608483&wl13=&veh=sem&gclid=EAIaIQobChMI3ea9v9Ht3QIV1bbACh0l3gC0EAQYAyABEgJ9uPD_BwE >

Sorry about the stupid long link.

Jon

[Ice-Tea]

Seen a load of those on Wish and others.

The only thing those turds have plenty of is BS.

[tsman]

Look down a bit at the notes from the seller Outright scamming going on there with this as their fail attempt at covering their ass.

Manufacturer's Nominal Capacity: 600,000mAh; Actual capacity: ~15000-18000mAh (If you mind it much, do not buy)

[amyk]

A real 600Ah battery:

https://www.solaronline.com.au/raylite-600ah-6v-deep-cycle-battery.html

Note the size, weight, and more importantly price.

[digsys]

Agreed, but I'd add a few comments ...
These sorts of figures are common in these types of devices .. To be fair, I'd guess they meant 6,000Ah peak current for 1 sec? so 200-300C?
I didn't believe those emergency car start packs could start a dead flat car, until I saw them in action. They were only the size of 1-2 cig packs.
150-180Ah is possibly 15-20C, which is doable for some chemistries. Shorter life, but doable. I'd assume that no-one would actually need to use it at that
rate, and if so, not for any length of time, so they're fine with that imo. "We" should be used to filtering headline claims :-)
The real problem I have with it is - NO charge profile / termination !!!! ... It seems. That would be an immediate NOPE for me.
Once you get past the headlines, the "Note:"s are not that unreasonable.

Note:
1.In order to fully activate the battery, please charge it via outlet or computer for 10 hours at least at the first 2-3 uses.
2.The energy transformation from solar to electricity is rather slow and the solar charging speed is subject to sunlight intensity and panel conversion rate.In daily life, we highly recommend charge it via wall outlet.
3.Fully charging by outlet takes approximately 10 hours.Do not charge it all day nor over voltage.
4.For safety, DO NOT leave the power bank charging in car in case of high temperature and avoid crashing.Do not make charge while charging itself.
5.Manufacturer's Nominal Capacity: 600,000mAh; Actual capacity: ~15000-18000mAh (If you mind it much, do not buy)

[Cyberdragon]

Why would you need the charge curve? Who's looking at that kind of stuff for a USB charger?

Most of these are one weak battery and the rest literal dirt inside (seach for youtube teardowns). The solar panel could even be paper (like in fake solar calculators). Occationally you get lucky and get a real one with decent (but way overmarked) capacity.

[Ice-Tea]

These sorts of figures are common in these types of devices .. To be fair, I'd guess they meant 6,000Ah peak current for 1 sec? so 200-300C?

That's not how Ah works. Aside from the fact that for a peak current of 600A you'd have to have total system resistance of less than 0,006 or a lot less if you want to end up with a meaninfull terminal voltage. Even if they're talking about the uS or nS discharge of ceramic caps it's unlikely.

[station240]

Agreed, but I'd add a few comments ...
These sorts of figures are common in these types of devices .. To be fair, I'd guess they meant 6,000Ah peak current for 1 sec? so 200-300C?

Ah is stored capacity in the battery, A (no h) is current.

600Ah = 600A over 1 hour
OR      = 1A over 600 hours
OR      = 2,160,000 over 1 second
Of course in reality, internal resistance etc means the battery could never supply more than a few amps or tens of amps at a time.

Even if they did mean A and not Ah, 600A from a powerbank sized battery is still questionable. Some Lithium car jump starters may manage it, but with dramatically short lifespans.

[CCitizenTO]

The batteries that run my pallet jack at work are I think somewhere between 80-120AH using conventional lead-acid batteries and they're pretty freaking huge and weigh enough that to change them you need a crane or something that's rated to lift 2 tons.