External rechargable battery packs

Forums › Apple iOS and devices › External rechargable battery packs

jonathan18

7407 posts

Uber Geek

ID Verified

Trusted

#133928 8-Nov-2013 09:57

Hi,

I'm looking at purchasing an external rechargable battery pack to charge portable devices - ie mobile phones and an iPad. 'Twas looking originally at one of those tiny units (eg 2,600 mAh) on a one-day deal website just for the mobiles, but after reading reviews of similar units on Amazon thought they were potentially a waste of money.

So... can anyone offer some advice as to what to look for, including capacity and output (say enough to charge both a standard Android handset and an iPad Air on a single charge), and potential recommended (but affordable) models?

I've seen a few on DX.com and eBay of 8,000 mAh+, which claim to be good for enough charges of an iPad, and offer two charging ports (one at 1A and the second at 2.1A). Given the higher needs of an iPad, I take it I should be looking for one like this?

Further, does price/quality make a significant difference or add a big risk to the equation? There are apparently bagain-priced units such as this one - should I be weary? (While I accept there's a risk the capacity of such a cheap unit is not as advertised, even if less wouldn't this do the job adequately, or are there problems to watch out for?).

Finally, if anyone has purchased such units overseas, have there been any issues with shipping (given these matters)?

Many thanks
Jonathan

Note:
* I've searched for other posts covering this topic, and haven't found any; please point me in the direction if this is a repeated question
* I'm unsure of the correct forum to post this, as it doesn't relate solely to any one forum - moderators, please move if you believe it should be located elsewhere.%MCEPASTEBIN%

1 | 2

2487 posts

Uber Geek
Inactive user

#929271 8-Nov-2013 10:08

A lot depends on how you intend to carry and use it.

I have built a system with a battery pack and a solar panel that I take away with me, it would do what you want, but you wouldn't want to lug it around, it weighs about 10kg.

So how exactly do you want to use it?

Samsung

Shop now on Samsung (affiliate link).

jonathan18

7407 posts

Uber Geek

ID Verified

Trusted

#929282 8-Nov-2013 10:46

andrewNZ: A lot depends on how you intend to carry and use it.

I have built a system with a battery pack and a solar panel that I take away with me, it would do what you want, but you wouldn't want to lug it around, it weighs about 10kg.

So how exactly do you want to use it?

Good point.

The idea is to have one that's not too large so it can just be thrown in my pack or similar. It therefore doesn't have to be lipstick-sized (like the puny models), but ideally wouldn't be much larger than say a couple of medium-sized phones stacked together (eg, 12 x 6 x 3cm).

ubergeeknz

3344 posts

Uber Geek

Trusted

Vocus

#929315 8-Nov-2013 11:35

Have a couple of these, they work well enough:

http://dx.com/p/185918

However don't believe the advertised capacity. Certainly helpful when we were traveling to keep our smartphones alive.

nathan

5695 posts

Uber Geek
Inactive user

#929336 8-Nov-2013 12:00

You get what you pay for. The cheap Chinese ones that I bought are all shot, and no where near the advertised capacity, but they're cheap, just like the cheap "64GB" USB keys. I know I've pulled various ones apart and looked inside. Some of them even have weights inside to make them feel heavier.

Even the ones I bought from daily deal/grab one etc were cheap Chinese crap as well

Mophie brand is at least reputable

rp1790

733 posts

Ultimate Geek

Lifetime subscriber

#929344 8-Nov-2013 12:19

Like Nathan says, you get what you pay for and the cheap DX battery's tend to have very low efficiency. Even the high quality batteries like Trent, Anker etc are only good to 70% of rated capacity (this is normal).

per chance, I have one of these for sale http://www.outdoorsupplies.co.nz/Power_Extreme.html. 9000mah with a solar panel that actually works.

PM me if interested, under half that listed price...

or, couple of highly recommended ones are the Anker Astro Slim3 (very slim), or the Anker 2ndGen Astro2 or 3.

Quite cheap on Amazon if you have a way of getting them shipped here at a decent price.

Amosnz

564 posts

Ultimate Geek

Lifetime subscriber

#929348 8-Nov-2013 12:24

I looked around on AliExpress and ended up choosing a supplier who looked like they were worth a shot (reasonable feedback, good information, no ridiculous size claims, not the cheapest).
I brought 5 at one time as several friends were wanting them as well, they ended up costing about $50NZD ea for a 10200mah after shipping.

Its important to note that there are losses involved in charging.
a) The capacity of the Li-Ion battery in the pack wont remain 100% forever.
b) The battery in the battery packs is 3.7v (like most phones), but this need to be raised to over 4.2v (its usually raised to 5v) to charge another 3.7v battery.

To find your end output you first need to calculate your the mWh. (internal voltage x internal capacity x remaining capacity) eg 3.7v x 10200mAh x 0.9 = 33300mWh
Then you need allow for the charging loss (available mWh / charging voltage x charging loss) eg 33300mWh / 5v * 0.9 = 5994mAh (0.85 - 0.9 is an average figure for a reasonable charging circuit).

So from your 10200mAh battery you effectively have 6000mAh of usable 'charge' in your end device. I'm charging a 1650mAh phone battery so can get 3-4 charges from a single battery pack charge (which i'm quite happy with).

EDIT:

I also highly rate these devices. Plug them between your Usb charger and the charging cable and monitor the voltage\amperage. Voltage is controlled by the charging unit while Amperage is controlled by the device. This can highlight what cable\charger combination works best for your device (lots of people have older\dodgy cables that are limiting the charging current).

http://www.aliexpress.com/item/5PCS-LOT-high-quality-Blue-New-Portable-Network-Mini-USB-Current-And-Voltage-Tester-Power-Bank/1044652671.html

Speedtest

ubergeeknz

3344 posts

Uber Geek

Trusted

Vocus

#929350 8-Nov-2013 12:26

ubergeeknz: Have a couple of these, they work well enough:

http://dx.com/p/185918

However don't believe the advertised capacity. Certainly helpful when we were traveling to keep our smartphones alive.

Happy to do a tear down. This particular unit seems to be pretty robust and has certainly survived plenty of abuse, physical and electrical...

jonathan18

7407 posts

Uber Geek

ID Verified

Trusted

#929396 8-Nov-2013 13:34

Thanks for all the responses thus far - some really useful information.

rp1790 - that unit looks great, and the use of solar power is sensible, but unfortunately even at half the new price it's outside of my budget!

ubergeeknz - that's def. in my price range (!), but it doesn't come with a lightning adapter (few seem to) - can one just plug a standard USB cable into the unit with the appropriate other end (ie, not use the supplied adapters, but just use, in this case, a lightning/USB cable)?

A few people selling Anker products on eBay, so that may offer an alternative to Amazon (don't think drop-shipping is worth it in this case).

Mophie powerstation models tend to be on the more expensive side, so ideally looking for something a bit cheaper.

Question - some of the cheaper/smaller units appear to claim a higher output through combining both ports - does that require the use of a y-calbe or similar?

Cheers
Jonathan

ubergeeknz

3344 posts

Uber Geek

Trusted

Vocus

#929405 8-Nov-2013 13:37

jonathan18: ubergeeknz - that's def. in my price range (!), but it doesn't come with a lightning adapter (few seem to) - can one just plug a standard USB cable into the unit with the appropriate other end (ie, not use the supplied adapters, but just use, in this case, a lightning/USB cable)?

Yep, you can plug in a standard cable. You need to honestly because the included cable doesn't have the data pins connected to anything, which most devices need to charge. We used it to successfully charge an iPhone 5 and a Galaxy Nexus, also an iPod touch 3.

freitasm

BDFL - Memuneh
78915 posts

Uber Geek

Administrator

ID Verified

Trusted

Geekzone

Lifetime subscriber

#929408 8-Nov-2013 13:41

nathan: You get what you pay for. The cheap Chinese ones that I bought are all shot, and no where near the advertised capacity, but they're cheap, just like the cheap "64GB" USB keys. I know I've pulled various ones apart and looked inside. Some of them even have weights inside to make them feel heavier.

Correct. Go for a New Trent. I have two of their New Trent PowerPak+ 13500. Also recommend the Motorola P4000.

My technology disclosure

1eStar

1604 posts

Uber Geek

#929463 8-Nov-2013 14:47

I have a 'pineng' brand one I bought off trademe, it's fantastic, possibly the fastest charger I have, supposed to be 6600mAh, will fill a galaxy note2 3100mAh battery while phone on, and a little to spare. I also have a zagg 6000 I imported from the states, which has a mains adapter built in, it will only just fill my note2 battery. You would need a very big one to refill an ipad.

Krishant007

1403 posts

Uber Geek

#929480 8-Nov-2013 14:56

I have got one of these ones here http://mylimeade.com/

I had sponsored them when they were in kickstart so got got a battery pack from them. I got the 13000mah one so it is enough to charge my phone a few times. Small enough for me to have it in my travel pack. Good experience so far with it.

HemantVallabh

21 posts

Geek

#929510 8-Nov-2013 15:20

You may want to look into Anker Astro Pro 2 (its a revised version of Anker Astro Pro) ;
http://www.amazon.com/gp/product/B00B45EOYS/ref=ox_sc_sfl_title_4?ie=UTF8&psc=1&smid=A294P4X9EWVXLJ

The Anker Astro Pro 2 is a beast. A real behemoth of an external battery.

A reviewer got over 4 charges of a Nexus 4 from around 10% to full, and around 3 charges of a Nexus 7. And all in a slim 185x125x15mm shell.

Review -http://news.enigma-tech.co.uk/2013/08/31/anker-astro-pro-2-20000mah-external-battery-review/

Product Features
20000mAh of capacity
Reliable lithium polymer battery ensures quality.
Equipped with two outputs for greater versatility: 1 DC 12V / 4A, 16V / 3.5A or 19V / 3A port and 1 USB 5V / 2.1A port.
Slim and stylish aluminum body ensures efficient heat dissipation, lighter weight, and durability.
4 smart LEDs keep you updated as to the remaining capacity.
Package contents: 1 Anker® Astro Pro2 20000mAh External Battery, 4 phone connectors, 10 laptop connectors, 1 USB cable, 1 DC power cable, 1 AC 100-240V power adapter, 1 accessories pouch, 1 user manual.

Size (LWH): 4.92 inches, 7.28 inches, 0.61 inches
Weight: 1.24 pounds

enfield

203 posts

Master Geek

#929817 9-Nov-2013 01:49

Are there any shipping issues with ordering from amazon.

jonathan18

7407 posts

Uber Geek

ID Verified

Trusted

#929819 9-Nov-2013 06:25

enfield: Are there any shipping issues with ordering from amazon.

Well, the main one I seem to have found is none of the battery products I've looked at on Amazon are shipped to my NZ address! Assume one needs to use YouShop or similar; but are they terribly fussy about sending batteries, considering it's an NZ Post business?

1 | 2