Very weight-efficient power bank

[DownEaster]

I bought this Ultrathin 20000mAh Portable Power Bank (5.3 oz./151 g including USB-to-µUSB cable) on eBay. It's noticeably lighter than the Anker PowerCore 10000, which at 6.35 oz./180 g was considered the "go-to" power bank among through-hikers just two years ago. It's way lighter than the similar-capacity Anker PowerCore 20100 at 12.56 oz./356 g. And it's cheap: under $9 shipped.

My unit came in silver; they also make them in blue, pink, black, and gold (randomly distributed). The housing appears to be aluminum. Given the low weight and high capacity I'd guess they're using lithium ion cells. There is no documentation at all, so I fiddled with it a bit to deduce the how-to.

There is one button, between "ON" and "OFF" labels. When I pressed it 4 small blue LEDs came on to indicate that it was about 4/4 charged (presumably 17,500+ mAh). There's a µUSB port labeled "IN". I plugged the included cable into that port, with the other end in a USB port in my PC. Immediately the first 3 blue LEDs lit up steadily, and the rightmost one started blinking to indicate that it was charging the last 1/4 of its capacity. There are two USB outputs, one labeled "OUT 1A" and the other labeled "OUT 2.1A"; I should be able to charge my phone and headlamp simultaneously. I don't know if this power bank supports powering other devices while it's being charged, but that's not a big concern because I've got a 4 USB port AC adapter so I won't need to do any daisy-chaining when I've got electrical outlet access.

There's no mention of "Quick Charge" or other such technology, so presumably charging won't be fast. Of the three prime metrics of backpacking technology (Light, Cheap, Good/Fast) I'm happy with the two I got here.

[DownEaster]

Here are a couple of pictures:
PowerBankORIGCrop.jpg PowerBankZoom.jpg

[The Kisco Kid]

It's also a generic unit shipped from Malaysia whereas Anker is a US-based company that offers an 18-month warranty and a thousand positive reviews on Amazon. If your unit fails, you're carrying 5.3 ounces of garbage. And 20,000mAh is overkill in my book (actual testing would likely prove this claim to be highly overstated).

I can make it 5 days easily without recharging my iphone (airplane mode with limited picture taking).

The Anker Powercore 5000 charges an iphone twice for 4.8 ounces. I have the 3350 mini, but don't carry it.

[Riocielo]

It's also a generic unit shipped from Malaysia whereas Anker is a US-based company that offers an 18-month warranty and a thousand positive reviews on Amazon. If your unit fails, you're carrying 5.3 ounces of garbage. And 20,000mAh is overkill in my book (actual testing would likely prove this claim to be highly overstated).

I can make it 5 days easily without recharging my iphone (airplane mode with limited picture taking).

The Anker Powercore 5000 charges an iphone twice for 4.8 ounces. I have the 3350 mini, but don't carry it.

And Anker has tremendous customer service, too.


Sent from my iPad using Tapatalk

[Slo-go'en]

A 20 Ah rating for a battery that small and light would be an incredible power density. More of a bomb then a power pack. I bet the true capacity is 1/4 of that and even that might be overly optimistic.

[DownEaster]

A 20 Ah rating for a battery that small and light would be an incredible power density. More of a bomb then a power pack. I bet the true capacity is 1/4 of that and even that might be overly optimistic.

I don't think the seller would have maintained their reputation if they sold 5000 mAh advertised as 20000 mAh. This is small by power bank standards, but the case still has enough volume to hold 8-10 of the 3000 mAh batteries used in my Moto phone. There's been so much production of lithium ion batteries that the technology has improved dramatically over the last few years. What I don't expect out of this power bank is speed. Delivering power at too great a rate (relative to what production line quality control allowed) was the problem with Samsung Galaxy Note 7 battery fires. I expect recharging to be an overnight affair.

[HooKooDooKu]

I don't think the seller would have maintained their reputation if they sold 5000 mAh advertised as 20000 mAh. This is small by power bank standards, but the case still has enough volume to hold 8-10 of the 3000 mAh batteries used in my Moto phone. There's been so much production of lithium ion batteries that the technology has improved dramatically over the last few years. What I don't expect out of this power bank is speed. Delivering power at too great a rate (relative to what production line quality control allowed) was the problem with Samsung Galaxy Note 7 battery fires. I expect recharging to be an overnight affair.

First of all, most of the general public doesn't know what 20000 mAh even means... the only way they would know if they have been taken is if they did a side-by-side comparison with a battery pack that can truly deliver 20000mAh of capacity.

But even if you are right about capacity and charging rate, then you're way off on how long it takes to charge the battery. I believe today's standard is that a "standard" charger can provide 0.5A of current, and a "quick" charger provided 2.0A or more. At 0.5A, it would take 40 hours to deliver 20000 mAh to the battery pack... and that's if the charging was 100% efficient. So if the battery can't take a rapid charge, then you're looking at two DAYS to recharge this battery, which means it's not good for a thru-hike unless you like hiking a 5 day hike week.

[DownEaster]

But even if you are right about capacity and charging rate, then you're way off on how long it takes to charge the battery. I believe today's standard is that a "standard" charger can provide 0.5A of current, and a "quick" charger provided 2.0A or more.

This isn't a "quick" charger, but it's labeled "INPUT DC 5V, 1.5A (max)". So 3X as fast as your low end estimate.

[HooKooDooKu]

A 20 Ah rating for a battery that small and light would be an incredible power density. More of a bomb then a power pack. I bet the true capacity is 1/4 of that and even that might be overly optimistic.

That's pretty much exactly what I was thinking when someone tries to compare a no-name battery pack to an Anker.

If a 20Ah Anker battery weighs 12.5oz, TNFW a no-name battery weighing only 5.3oz is going to come close to true 20Ah usable capacity.

[DownEaster]

If a 20Ah Anker battery weighs 12.5oz, TNFW a no-name battery weighing only 5.3oz is going to come close to true 20Ah usable capacity.

You're comparing Anker's 3-year-old design (guestimating from early 2015 Amazon reviews of the PowerCore 20100) to something that only started selling on eBay recently. The Anker uses 6 18650 Panasonic 3400mAh batteries - NCR18650B, and there are better batteries available today.

[HooKooDooKu]

You're comparing Anker's 3-year-old design (guestimating from early 2015 Amazon reviews of the PowerCore 20100) to something that only started selling on eBay recently. The Anker uses 6 18650 Panasonic 3400mAh batteries - NCR18650B, and there are better batteries available today.

One of Anker's latest releases is a 10,000mAh battery pack that weighs 7.4oz. Based on review days, I'd say the battery was released in May of this year.
This Malaysian battery is claiming twice that capacity for 30% less weight.

"If it's too goo to be true, it probably is"

That phrase fits battery packs just as well as everything else in life.

[Maineiac64]

Wow, great find. Let us know how it works in the field.

[DownEaster]

@Kisco Kid:

I've got a Moto G4 with a 3000 mAh battery. My Vansky headlamp has a 1200 mAh battery. I don't know what the capacity is on my $8 backup/belt-mounted light, but one full night of hiking with GPS navigation is likely to use more than 5000 mAh. I'm glad to have this as an option if the forecast is for a clear night followed by a day of rain.

If I were to carry an Anker power bank and it failed, I'd be carrying garbage -- with a chance to replace that garbage with a functioning power bank at some time in the future, via a procedure that's quite difficult to comply with if you're on the trail. The seller I bought this from has over 29,000 reviews with a 98.7% positive rating.

If you don't like this product because it comes from Malaysia, then you certainly shouldn't buy it. However, you're implying that the quality is poor without any evidence, and also that the very efficient power-to-weight ratio doesn't matter. I think you'll find a lot of backpackers would disagree with you.

[Starchild]

I also question the power rating on that unit, but that does not mean it's a bad buy, it might be very good even if lower than advertized.

Funny thing about Li-ion batteries you can get a lot more power out of them then most manufacturers will allow. Li-ion is artificially limited in how full it can get and how low it can get (false 0% and false 100% state of charge). This is because if they use the true 0% and true 100% you expose the battery to conditions that will greatly shorten it's life. (it's also the reason it's not good to leave laptops plugged in all the time, as you approach the fully charged limit it does eat away the life, just not as fast as true 100%). Some no name manufactured push these limits and as such get many more mAh out of the batteries, but also dramatically shorten the life.

IDK if they one you got does this or not, I've had both, and I have had very good luck with a 'no-name' battery pack that seemed to deliver over many years.

As for Anker, they seem to be a good company that would not monkey around with the limits to extend run time (though not no one has stated how their customer service is, no less on trail), however 'American made' does not equal quality, in some ways we have sadly lost manufacturing quality, and there is the American profit motive which drives prices up, riding on patriotism which masquerades for quality.

[Gambit McCrae]

Gambit is a firm believer in you get what you pay for. Proves itself time after time. I have been down the "cheap 20,000 mah power bank" Trail, And after night 1 it was dead. Big ol 18$ hunk of crap.

I carry an anchor now, and have ben quite pleased. Got it on amazon for a good deal. $48 bucks or so. I use my phone like its going out of style, music - videos - texting - calling - pictures - guthooks...its used on and off all day long on the trail. So I have a pretty solid battery bank, but its not even 20 mah.

[MuddyWaters]

Nope
Cheap batteries are notorious for being under capacity

Everybody know that

[DownEaster]

From what I can tell, Anker is still using cylindrical cells in their battery packs, whereas newer batteries like the one in my phone are flat. There's more casing overhead (weight) in cylindrical cells.

[MuddyWaters]

From what I can tell, Anker is still using cylindrical cells in their battery packs, whereas newer batteries like the one in my phone are flat. There's more casing overhead (weight) in cylindrical cells.

Actually no.
Thin and flat results in larger surface area to volume ratio.ie..more casing material required

I have a flat, lightwt , lipo battery pack. It weighs 3.25 oz , 4000 mah.

[The Kisco Kid]

@DownEaster

Your avatar says you're a thru-hiker in planning. Folks are trying to be helpful here. I wouldn't take it personally (unless you invented this battery )

#1 - the failure rate for this power pack is likely to be high. It's just too good to be true. A 98.7% positive feedback on eBay is not so good. Feedback on eBay is highly overrated. I recommend opening up the seller's feedback page and then clicking on the negative feedback ratings. You'll be able to read the 381 negative feedback comments this year, including: "Real measured capacity liitokallaa only 450-500 mAh!!!cheating! 12 times LEss!!!" for another battery from the same seller.

#2 - you likely won't need all that storage power the way your describing your potential usage. The Vansky headlamp you mentioned has rechargeable batteries. For $9.99 it will likely fail and the batteries will run out of their charge when you least expect it. When you're in the backcountry stay away from rechargeable batteries if you can. Here's the Petzl E+LITe headlamp I've used for years. Weighs 1 ounce. The Vansky headlamp weights 2.5 oz. + cords and you need a heavier power pack to keep the thing charged. You mentioned hiking with GPS navigation? Navigation is a non-issue on the AT. (The CDT is a different story.) The AT is so well marked, most hikers don't even carry a map and compass. Here's the 0.2 compass I carry.

On the trail it's not about the latest technology, but what is proven to function when you need it most. Have fun planning your hike and happy trails!

[HooKooDooKu]

From what I can tell, Anker is still using cylindrical cells in their battery packs, whereas newer batteries like the one in my phone are flat. There's more casing overhead (weight) in cylindrical cells.

Perhaps true, but the point is irrelevant.

The bulk of the weight in these battery packs is going to be in the batteries and not the case.

Add to the the fact that my latest comparison to the 20000mAh Malaysian battery was to an Anker 10000mAh battery and the deal still sounds too good to be true.