Develop Bugs

What is your power bank?

Hi All! So this is my first time starting a new thread so I hope I'm doing this right. I couldn't really find a thread specifically for battery banks or battery backups so I thought I'd start one.
I was wondering what is everyone's method of backing up/recharging your battery for your cellphones? For me, the battery that comes with my phone is enough to get me through the day usually and I just charge it every night while I sleep. If I go on trips, I use the Rav Power 10000 mah battery bank. I find this a bit bulky but it works great and lasts many charges before I have to recharge again.
Everyone's taste and preferences are different so I'm seeing what other options are out there that may be lighter in weight. I'm thinking of getting their smaller one, the 5200 mah, and have this in my backpack or car for just in case.
Any mini reviews of what you have would be great :good:

Wow, cool gadgets, I need to get a bank for just-in-case emergencies. Thanks Currently i use a solar powered charger, which is really slow and somethings doesn't work as desired. Looks similar to this http://www.amazon.com/External-Univ...=8-4&keywords=solar+powered+cellphone+charger

Ive bought one at sunsky from china battery about 4000mah, but it was year before, now there is a better.

I used to have a bank that looked like a GBA SP, with foldable screens. In the screens were two solar panels, which charged the battery of, I think, about 2000mAh or something like that. The thing is now broken though. Still looking for a nice (affordable) replacement

Mine is Anker 5600

I use the Belkin 4000, size similar to a ext HDD and look nice, pocketable too
http://www.techhypermart.com/belkin-f8m160ak-portable-battery-pack-4000.html

Charger considerations
Hi,
I need advise for the following:
Charger A (Li-polymer battery) output : 5V, 1A
Charger B (Li-polymer battery) output : 5V, 500mA
Device input: 5V, 750mAH (Li-ion / Li-polymer)
When using Charger A, some people comment that it will limit the current of 750mAH for the device and the device's battery should be fine since both the charger and device are at 5V. However, some people comment that this will shorten the battery life of the device since it will perform a 'quick charge' using 1A.
When using Charger B, some people comment that the device will draw more current than it can deliver and causes it to heat up and reduces the charger's life. However, some people comment that Charger B will extend the battery life of the device since it performs a 'slow charge'.
I also read that USB pins on the charger denotes if the charger is a PC or a dedicated charger. If it is a PC, the device will limit the drawing current. If it is a dedicated charger, the device will draw more current to charge itself.
I am confused as to who is right and which charger should i be using.
Can someone enlighten me ?
Thank you very much.

bought this one from Ebay, has not yet arrived, therefore I cannot tell if its good or not.
but for its price its quite a good bet, 12000mAh for 33 bucks (on sale until tomorrow)
not able to post links, just type w ww. before the following
ebay.com/itm/12000mAh-External-Power-Bank-Battery-Charger-iPhone-3-4S-iPad-3-2-Blackberry-/280947027345

Zagg sparq 2.0 highly recommended
Sent from my GT-N7100 using xda premium

I recommend Anker 5600 is very good for that stuff.

Hi, I use choiix power fort 10Wh http://www.coolermaster-usa.com/product.php?product_id=3001 it have 2700mAh and it's small and looks very nice. It can give one full charge for my SGSIII

I went on a trip this year and searched for a good bank, and this showed up.
http://www.sayes.co/20-powerbank.html
I tried it and it was really good, it has lots of adapters and it's cheap =P

I was able to order a RavPower 5600mAh on sale a while back ago, that was posted on slickdeals. here. I am pretty happy with the performance of the little backup, it defiantly gets the job done. My only complaint is that the body gets scratched up easily.

I was comparing the Ravpower and the Anker 5600 and they both look exactly the same except that both are branded with their logos. So I'm wondering if they're from the same manufacturer. Going to have to do some more research. However my current Ravpower power bank I do have is working great and I love this thing for trips.
I'm also thinking of getting a solar one for my 3day emergency/bug out bag. Thanks for all the suggestions.

Green Ranger said:
I was comparing the Ravpower and the Anker 5600 and they both look exactly the same except that both are branded with their logos. So I'm wondering if they're from the same manufacturer. Going to have to do some more research. However my current Ravpower power bank I do have is working great and I love this thing for trips.
I'm also thinking of getting a solar one for my 3day emergency/bug out bag. Thanks for all the suggestions.
Click to expand...
Click to collapse
Yeah, can someone please let me know if they are the exact same manufactuers, except for the company logos on them? I am deciding between the two. Also, what do you guys think of their 2600maH stick version? Which manufactuer would you go for over the other and why? I am very interested.

I'm using a "Scosche SolBAT II Solar Powered Backup Battery and Charger" which I bought off Amazon for something ridiculous like $15 last year.
I bought it for hiking mostly as an emergency charger. I use a Huawei phone as a GPS out in the wilderness, and the GPS app (Androzic) is quite power intensive. I have also used the same device on an iPhone and an iPod touch. The Huawei phone will receive a full charge from this battery, but the iDevices will only go to around 75%.
The solar cell on the back of the battery isn't all that efficient and will take about two days to charge the internal battery, but having it there gives you more options should an emergency occur while in the wilderness. A half hour charging in full sunlight would provide enough power for a short call or a couple of texts to family or emergency services.
The device comes with suction cups and a small carabiner, so it can be stuck to the inside of your car window or clipped to the back of your rucksack. The device is lighter and smaller than the average smartphone and can be fully charged by USB in about three hours. Interestingly, the device has a LOT of bad reviews on Amazon, so maybe they simply sent me a good one.
I also have a very cheap and nasty handcrank USB charger from dealextreme which can be used to add a bit of juice to the solar battery pack at night or in cloudy weather or can directly charge the phone in an emergency. It's a little flimsy and takes a fair bit of cranking to get enough juice for even one call, but it weighs nothing, cost about $2 and is cheap insurance out in the boonies.
My list of power equipment for the phone/GPS and the iPod Touch for a multi-day walk are as follows:
Short Micro USB cable x 1
iPod USB cable x 1
Scosche SolBAT II battery/charger with alloy carabiner
DX hand crank battery charger
Total weight is less than 200 grams

nottellingeither said:
I'm using a "Scosche SolBAT II Solar Powered Backup Battery and Charger" which I bought off Amazon for something ridiculous like $15 last year.
I bought it for hiking mostly as an emergency charger. I use a Huawei phone as a GPS out in the wilderness, and the GPS app (Androzic) is quite power intensive. I have also used the same device on an iPhone and an iPod touch. The Huawei phone will receive a full charge from this battery, but the iDevices will only go to around 75%.
The solar cell on the back of the battery isn't all that efficient and will take about two days to charge the internal battery, but having it there gives you more options should an emergency occur while in the wilderness. A half hour charging in full sunlight would provide enough power for a short call or a couple of texts to family or emergency services.
The device comes with suction cups and a small carabiner, so it can be stuck to the inside of your car window or clipped to the back of your rucksack. The device is lighter and smaller than the average smartphone and can be fully charged by USB in about three hours. Interestingly, the device has a LOT of bad reviews on Amazon, so maybe they simply sent me a good one.
I also have a very cheap and nasty handcrank USB charger from dealextreme which can be used to add a bit of juice to the solar battery pack at night or in cloudy weather or can directly charge the phone in an emergency. It's a little flimsy and takes a fair bit of cranking to get enough juice for even one call, but it weighs nothing, cost about $2 and is cheap insurance out in the boonies.
My list of power equipment for the phone/GPS and the iPod Touch for a multi-day walk are as follows:
Short Micro USB cable x 1
iPod USB cable x 1
Scosche SolBAT II battery/charger with alloy carabiner
DX hand crank battery charger
Total weight is less than 200 grams
Click to expand...
Click to collapse
That is a nice list of equipment. How is the solar powered charger coming along?

tgmeyer said:
Yeah, can someone please let me know if they are the exact same manufactuers, except for the company logos on them? I am deciding between the two. Also, what do you guys think of their 2600maH stick version? Which manufactuer would you go for over the other and why? I am very interested.
Click to expand...
Click to collapse
Honestly i went with pricing. I assume if they look the same they are from the same vendors/manufactures but different brand/company. Reviews for both sound very good too. Ravpower had a promo going on a while back and i tend to see them pop up from time to time on slick deals. The stick might give you one charge but since it looks smaller than the rest, it may be the easiest and lightest to carry around. I say get a decent sized one. Anywhere between 5600mah to 10000mah so you can go through a few charges without needing to charge again.

I have a 6600 mAh(well, in my experience it's not true, more like 4-4.5k), but I rarely use it after I bought a tablet with a fullsized usb port in it.

solar charger
I was looking for a solar charger. I bougth one but it crashed in two days. Therefore I returned it and now I am waiting for another one. In the place I live there are few options

Review of Anker Astro Slim2 4500 mAh External battery w/pics!!!

This is a review of Anker Astro Slim2 4500 mAh dual output External battery (5V 1A Input, 5V 1A dual output with built in hideaway cable for one of the output ports): http://www.ianker.com/product/79ANS4552-BA
Every time I start to think about extended battery, I run into a big question of what am I going to do with all my cases that no longer going to fit the phone. That is why I decided to explore external battery solution. I don't trust no-name ebay brands because those have overly exaggerated capacity rating. So I turned to a trusted brand, Anker, since so many people in this forum had a lot of positive things to say about their products. In comparison to our stock 3100 mAh battery, this Slim2 external battery is not over the top with its 4500 mAh labeled capacity. If you take into consideration all the conversion factors between external lithium battery, USB port transport, and back to phone's battery, we are talking about final capacity which could realistically be closer to 3100 mAh (and actually stated in the manual as 30% internal power consumption due to losses). What makes the battery stand out is it's unbelievable slim form factor and all the design details that go with it.
When you first take it in your hand you can't believe how light and slim it is. We are talking about 10mm slim! I actually took exact measurement with my digital caliper and found it to be 4.97" x 2.52" x 0.41" (126.34mm x 64.08mm x 10.64mm) and weight to be 4.1 oz (116g) which also includes built-in micro-usb cable. I can see that a lot of thought went into it's design. The case of this external battery is made out of tough plastic with a matte finish and sides have a rubbery finish for a nice grip. The form factor is very slick, something that can go easily into your pocket or purse or even carried in one hand attached externally to your phone. The unit has one micro-usb input port which is cleverly covered by hideaway micro-usb output cable/connector, and another regular usb output port. Pretty much it eliminates a need to carry any external cables since the one you need for your Android device is already built-in. The cable for that external micro-usb connector is flat, flexible, and just long enough to wrap around the end of the battery pack, and it should be sufficient to connect to any phone or tablet. As part of the accessories that come with Slim2, you also get usb-to-micro-usb extension cable with additional mini-usb adapter and Apple 30pin adapter. This second regular usb Output port also comes very handy for another important reason. If you look at the pictures I took, you can see that hideaway micro-usb connector has trapezoid shape. It should work fine with most of the slim or rugged cases that have silicone or tpu inner shell/bumper surrounding micro-usb port opening. With my UAG case is was a very close call where I had to push it in with some force. This hideaway port will not work with Defender case due to its inner plastic shell suited and standard rectangular port opening. That's where 2nd usb output port comes in handy to use external usb cable with a regular micro-usb connector.
There is no power button, instead you have auto on/off capability and display of battery capacity using 4 led lights partitioned in 25% increments. Every time you plug/unplug power cable those lights lit up to show you capacity level or charging level. Also, auto shut off reassures that you will not overcharge the battery once it reaches 100%. I charged this battery to 100% (indicated by 4 solid lights), and used with my Note 2 which was down to 55%. To my surprise charging time was very fast considering it has 1A output, and I was able to get my phone back to 100% within 1.5 hour with 2 led lights remaining thus indicating that battery still had 50% of charge left. That is consistent with my assumption of battery capacity to be around 3100 mAh.
Overall, I'm very pleased with Slim2 as an emergency battery pack. It's slim, easy to grip, light weight, small footprint, NO need for external cables (unless if you have a case like Defender), and ability to charge 2 devices simultaneously. Furthermore, if you remember my mod with clip stand from a car mount, I actually found it to fit together really well which is great, for example, while watching a movie and charging your phone up at the same. Everything is captured in pictures below!
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With a clip-stand:

awesome, gonna get one

initial_k said:
awesome, gonna get one
Click to expand...
Click to collapse
Keep in mind, you will get about 3100 mAh of actual charge, these external batteries actual rating is 30% down from the label due to usb 5V conversion factor.
This one is not the highest capacity, but it's the slimmest one for sure. It actually saved us a few times when our Nexus 7 tablet was drained and I just sticked it in between book-cover case and was using a tablet while charging it up (with 1A output you get a relatively decent charging speed).

vectron said:
Keep in mind, you will get about 3100 mAh of actual charge, these external batteries actual rating is 30% down from the label due to usb 5V conversion factor.
This one is not the highest capacity, but it's the slimmest one for sure. It actually saved us a few times when our Nexus 7 tablet was drained and I just sticked it in between book-cover case and was using a tablet while charging it up (with 1A output you get a relatively decent charging speed).
Click to expand...
Click to collapse
Need to get something for my kid's Droid DNA. It doesn't have a lot of power for a day traipsing in the wilderness, and won't take a larger external. This might fit the bill.

drnihili said:
Need to get something for my kid's Droid DNA. It doesn't have a lot of power for a day traipsing in the wilderness, and won't take a larger external. This might fit the bill.
Click to expand...
Click to collapse
Anker Astro 3E is only $10 more and offers 10,000 mAh versus this 4500 mAh. Unless they need something super slim/light, Astro 3E is a better value in my opinion, and still has a relatively small footprint.

vectron said:
Anker Astro 3E is only $10 more and offers 10,000 mAh versus this 4500 mAh. Unless they need something super slim/light, Astro 3E is a better value in my opinion, and still has a relatively small footprint.
Click to expand...
Click to collapse
No astro 4 is better 13000mAh
Sent from my SPH-L900 using xda app-developers app

vectron said:
Anker Astro 3E is only $10 more and offers 10,000 mAh versus this 4500 mAh. Unless they need something super slim/light, Astro 3E is a better value in my opinion, and still has a relatively small footprint.
Click to expand...
Click to collapse
He'd like both.
We live (or soon will) in 70 acres of forest and he likes to go off wandering most of the day. Between camera, gps tracking and the like that can be a challenge for the DNA, especially if he's forgotten to top it off first. I'm really looking for something he can just toss in his pocket/daypack to be sure he has enough juice to get through the day. Looking at the 5600mah also. It may be more pocektable. He's never gone over multiple days unless I'm' with him, and I've got the ZL9300, so no worries there. I'll have a look at the 3E and the 4 to see how much bigger they are. Certainly they'r a better value per mah, but the key is finding something that's very easy for him to take. As with cameras, the best external battery is the one you have with you when you need it.
EDIT: I like the form factor of the 5600 and 8400 better, but I like the included cable of this model. An external battery is of no use if you don't have a cable, and you know how 14 year olds can be ...

5600 and 8400 from Anker are the old models.
Btw, I just received and charging Astro Pro 14400 mAh - that one is a monster with two usb ports and a separate 9V/12V DC outputs. Will have review in a day or two

Will the attached micro usb fit the case mate tough?
Sent from my SGH-I317M using xda app-developers app

vr_nguyen said:
Well the attached micro usb fit the case mate tough?
Sent from my SGH-I317M using xda app-developers app
Click to expand...
Click to collapse
It should. With both UAG and CaseMate Tough cases the opening around micro-usb port is tpu material to that connector can wedge right in there. Tough port opening is wider than UAG, and I remember I had no issues wedging that micro usb connector right into UAG, so it should work with Tough as well.

I'm trying to think what's the advantage of this over an extra battery. It would make sense for those who carry several devices and does not want to carry several batteries. I for one only carry one device at a time, so I guess this would be useless for me.
Can you guys point out any other scenarios?
TIA
Sent from my SGH-I317M using xda app-developers app

vr_nguyen said:
I'm trying to think what's the advantage of this over an extra battery. It would make sense for those who carry several devices and does not want to carry several batteries. I for one only carry one device at a time, so I guess this would be useless for me.
Can you guys point out any other scenarios?
TIA
Sent from my SGH-I317M using xda app-developers app
Click to expand...
Click to collapse
When you're at home that's pretty much primarily use now the reason why the slim is more portable hence you can bring out on the road
Sent from my SPH-L900 using xda app-developers app

The reason to use this ultra-slim battery is very simple, you can hold it connected to the phone while actually using the phone.
This is a picture from Anker webpage. So for example you are facing a scenario where your phone went dead or you are on call or browsing and down to 2% - but you have to continue using your phone and don't have time to wait for charging. This is the only battery that will allow you to do that because you can actually hold it physically together with your phone (and use built-in cable) and it will be charging your phone while you are using it.

I just purchased this for powering my phone and other equipment when away from chargers.
I really like the form factor and the micro-USB cable is very clever. However this battery has a glaring problem (in my opinion): you cannot charge your phone from the battery while charging the battery. When traveling light and grabbing an all-night recharge this would be a nice feature to have to not have to carry two chargers and cables.
- Juha

kuikkaj said:
I just purchased this for powering my phone and other equipment when away from chargers.
I really like the form factor and the micro-USB cable is very clever. However this battery has a glaring problem (in my opinion): you cannot charge your phone from the battery while charging the battery. When traveling light and grabbing an all-night recharge this would be a nice feature to have to not have to carry two chargers and cables.
- Juha
Click to expand...
Click to collapse
This feature disabled on purpose. I know some other vendors enable it, but it actually not good for the battery. You have two connections, from battery to a phone for charging of the phone, and from wall charger to a battery for charging of the battery. If you have both connected at the same time you will need a way to bypass charging of the battery until phone is charged up first - that pass will be extremely inefficient and it will take you almost twice as long to charge the battery due to all conversions. Then once you done, you will need another mechanism to stop charging of the phone and to switch to charging of the battery, and while you are doing that phone will be discharging so you will have to pick up it's charge as well. Too complicated, too inefficient, and complexity of control circuit will work against reliability of the device. At night it's much easier to charge phone from one outlet and battery from another, just need to get dual usb wall charger, like one of those 2A/1A ones. Charge the phone from 2A output and charge the battery from 1A output.

vectron said:
This feature disabled on purpose. I know some other vendors enable it, but it actually not good for the battery. You have two connections, from battery to a phone for charging of the phone, and from wall charger to a battery for charging of the battery. If you have both connected at the same time you will need a way to bypass charging of the battery until phone is charged up first - that pass will be extremely inefficient and it will take you almost twice as long to charge the battery due to all conversions. Then once you done, you will need another mechanism to stop charging of the phone and to switch to charging of the battery, and while you are doing that phone will be discharging so you will have to pick up it's charge as well. Too complicated, too inefficient, and complexity of control circuit will work against reliability of the device. At night it's much easier to charge phone from one outlet and battery from another, just need to get dual usb wall charger, like one of those 2A/1A ones. Charge the phone from 2A output and charge the battery from 1A output.
Click to expand...
Click to collapse
I agree, the feature would make the design slightly more complex due to increased logic, unless the used charge IC supported something like that internally. It would not necessarily have to be inefficient as you can bypass the charger and just feed the input directly to output. Could be as simple as a switch controlled by the battery full information of the charger.
But I digress. For most people this is not an issue, I just like to travel light. :cyclops:
Would you by any chance know of a battery pack or vendor that would have this feature?
- Juha

kuikkaj said:
I agree, the feature would make the design slightly more complex due to increased logic, unless the used charge IC supported something like that internally. It would not necessarily have to be inefficient as you can bypass the charger and just feed the input directly to output. Could be as simple as a switch controlled by the battery full information of the charger.
But I digress. For most people this is not an issue, I just like to travel light. :cyclops:
Would you by any chance know of a battery pack or vendor that would have this feature?
- Juha
Click to expand...
Click to collapse
I have reviewed so many Anker external batteries, already lost a count of everything lol!!! I think they had one that was charging both phone and charger, but they wouldn't recommend it. Or maybe that was one of the NewTrent batteries (NT70) I have reviewed in the past.
Btw, Anker is releasing AstroSlim3 in a week or so with 6000 mAh capacity (http://www.amazon.com/gp/product/B00CEZJT2E) and new Astro 3 with 12000 mAh (http://www.amazon.com/gp/product/B00CEZBKTO) with led indicator for capacity and no power button, activated by shaking it. Don't know the pricing yet, and hopefully will get both of these units for review as well.

Anker 2nd Gen Astro2 9000mAh Battery Pack

http://www.amazon.com/Anker-Portabl...?ie=UTF8&qid=1389368123&sr=8-6&keywords=anker
Anker 2nd Gen Astro2 9000mAh
Manufacturer Description
Charges the iPhone 4+ times and large-capacity phones like the Galaxy S4 almost three times. Total charge output of 3A among two charging ports. One Smart Port (5V / 2.4A max) offers truly maximum speed charges to ANY device, including the iPad or even the Samsung Galaxy Tab. One additional port charges Android smartphones at full speed.
High energy efficiency rate, 10% above previous generation Astros and many current standard alternatives, gives you up to an extra full charge for your smartphone. Sturdy construction and matte finish withstands bumps and drops. Grade A cells and premium chips ensure reliability.
A "shake" starts a charge or displays the remaining power level. The ultra-low power consumption (100, 000 shakes consumes less than 1%) Smart LED display, designed with 10 LEDs, balances accuracy and aesthetics.
Input: 5V / 1.2A; Use a 1.2A adapter for fastest charging time (8 hours).
Packaging
It’s simple and minimal which is a good thing. Also, the Packaging is recyclable for you ECO friendly people out there.
Specs
Package contents: Anker® 2nd Generation Astro2 External Battery, Micro USB cable, travel pouch, instruction manual.
It’s about the perfect size for a battery pack. Easily handled with one hand, not too thick.
Here are the output details for the two ports based upon the type of device you are trying to charge:
Type of product-----------------Smart Port------Universal Port
iPad IOS 5 and above----------2.4 Amps--------1.5 Amps
iPad below IOS 5----------------2.4 Amps--------N/A
iPhone IOS 5 and above-------1 Amp------------½ Amp
iPhone below IOS 5------------1 Amp------------N/A
Android Phones-----------------1.5 Amps--------1.5 Amps
Android Tablets-----------------2 Amps-----------2 Amps
Samsung Galaxy Tablets------2 Amps-----------N/A
Other cellphones---------------1.5 Amps--------1.5 Amps
Build Quality
It’s made of plastic but of a very good build. It has a two tone look of glossy black ends with the rest being a matte black. It’s seemless from the transition from the glossy to matte. There doesn’t seem to be any gaps between the pieces. All ports are at on end. It has a ring indicators with 10 “pies”. Each pie represents 10% charge of the battery pack. It’s a nice soft white light and not too birght that a lot of electronics suffer from.
It just has one Anker logo at the top and very minimalistic.
Testing/Performance
It has a Shake feature to activate charging. Simply plug in a device and give it a quick shake and the device and start charging. Now I know what you’re thinking; leaving it in your bag will discharge the battery for no reason if nothing is plugged in. That isn’t true, it has a super smart super low discharge even when left in a bag where accidental shakes will happen.
I decided to test this out. Leaving it my baby nieces rocker, it didn’t even discharge 1 pie (10%) when left over 18 hours in the rocker.
Using the following devices:
Nexus 5
Nexus 7 2013
S3
Ipad 4
Ipad 2
Sansa Clip Zip Mp3 player
All were able to be charged without a hitch. It is to note that the max output is 3 amps. So trying to charge two devices that require 2.1 amps is simply not possible at full speed. It would charge t but at a slow rate. It can charge a 2.1 and 1 amp device without a hiccup though.
Either port would be fine for any smartphone under the sun.
Using a Nexus 5 at 26%:
30 mins – 55%
1h 13 mins – 91%
1h 28 mins – 100%
It used 3 pies (30%) to go from 26% to 100%.
Conclusion
It’s a great battery pack that has a nice shake feature! One of the better sized battery packs that has a good capacity compared to its size. A must have all tech warriors on the go.
Note- I was supplied a sample for test and evaluation, and I promised that my review is fair and honest

Did you buy this or was it a gift from Anker for review?

This is a great device. I have the 13Ah charger, and it seriously holds a charge. I've never gotten it empty before because it'll charge my phone for a week. Looking forward to the next time I fly so I can use it.

Any chance you could actually test the output with a 12w ipad? I just got a new anker astro3, and it only charger at 2.1, not a 2.4amp
Easiest way to test it is to download "batterylife"(free) in cydia, or time charging the default charger compared to the anker.
Thank you! It is advertised everywhere as 2.4amp, but it seems like they do not have that feature!

Review of Anker Astro E7 25600 mAh external battery w/lots of pics!!!

This is a review of Anker Astro E7 25600 mAh external battery. http://www.amazon.com/Ultra-High-Capacity-25600mAh-External-Technology/dp/B00M3073L4/
About a week ago we were expecting a big snow storm. Thank God it turned out to be nothing, but in preparation I went through my usual routine of getting extra food and water, getting extra gasoline for our generator, and.... making sure all my Anker batteries are charged up! I often talk about external batteries as a boost source on the go when you want to have something small and pocket friendly. But if you want to be prepared for any emergency or planning to be away from a power source for days - you want to have a battery with a big enough capacity, and that's what 2nd gen Astro E7 delivers with its enormous 25600 mAh. Here is more about it.
After reviewing so many different Anker batteries, I'm already used to their environmentally friendly packaging and typical accessories of a high quality usb to micro-usb cable and storage pouch. But it's always a surprise to see how big the battery turns out to be based on the advertised capacity. You have to realize that increased capacity comes at a price of increased size and additional weight. It's a simple math - higher capacity means more internal battery cells. That is why I never trust some of the budget ebay and other retailers small battery bricks claiming 20k mAh in a footprint of 10k battery. Out of the box, you will definitely feel the weight of E7 at almost 16oz (450g), but it's still manageable thanks to its slick rectangular shape with rounded edges which is easy to handle. With a dimensions of 166 × 80 × 22mm (6.5 × 3.1 × 0.9in) it can actually slip into your front pocket or cargo pants side pocket without a problem, though it will be noticeable. The whole intent of this battery is not to be a small portable back up charger but rather a portable charging power station to give your phones and tablets a boost with up to10 combined charges.
The design is similar to their other 2nd gen E-models, just scaled up in size. You still get a slick piano finish plastic body, very sturdy, no flex. Also a power button on the side to turn the battery on/off, though I found it starts charging automatically as soon as it detects attached device. Another function of power button is to turn built-in white LED by holding and pressing this button. LED functionality is a welcome bonus, especially in emergency situation to use as a portable flashlight or to lit up usb ports so you can connect the cable in the dark. The top of the battery has 4 LEDs to indicate remaining power or to display charging power. These indicate 25% per LED, not as accurate as a regular Astro line with 10-led indicators, but for bulk charging this should be sufficient. I also prefer led indicators over some other batteries that use LCD display which drains the battery. And speaking for that, I can confirm that all of my 2nd gen Anker batteries hold the charge for multiple months when not in use.
E7 model comes with one micro-usb input charging port and 3 full size usb power output ports, each equipped with PowerIQ feature that automatically adjusts current supply per attached device requirement. So if you have an old Android phone, it will source only 1A, while newer phones will get 2A, and your latest iPad will be charging at full 2.4A. Just have to keep in mind that a total combined current can't exceed 4A. Another very important feature is 2A charging input. With a capacity of 25,600 mAh it will take you over a day to charge this battery from empty using a typical 1A charger. Here with 2A wall charger you can juice it up to 100% in approximately 12-13 hours. Also, it's very important to keep in mind that with any battery you have to take into account the convergence efficiency since you are going between 3.7V cells and 5V usb interface. Anker converters are usually very efficient and deliver only 10-12% drop, bringing it closer to 90% efficiency. In comparison, a lot of other batteries are struggling around 80%. With Anker E7 battery you can get about 23,000 mAh of the actual charging capacity.
Overall, I'm always impressed with power products from Anker and consider their external batteries to be among the best. You don't have to take my word for it or to tell me that I'm biased, just search our community for all the positive feedback or look on Amazon where it's #1 best seller in every category with thousands of 5-star reviews. The combination of top quality LG battery cells, durable design, super fast input charging without a need to use proprietary connectors (just a standard micro-usb), bonus of LED light, high efficiency and huge storage capacity, and their 18-months warranty and excellent support - makes this battery my top recommendation, despite a price tag of $80 (just factor in combined cost of smaller capacity batteries).
Here are the pictures.
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E7 next to E4

vectron said:
This is a review of Anker Astro E7 25600 mAh external battery. http://www.amazon.com/Ultra-High-Capacity-25600mAh-External-Technology/dp/B00M3073L4/
About a week ago we were expecting a big snow storm. Thank God it turned out to be nothing, but in preparation I went through my usual routine of getting extra food and water, getting extra gasoline for our generator, and.... making sure all my Anker batteries are charged up! I often talk about external batteries as a boost source on the go when you want to have something small and pocket friendly. But if you want to be prepared for any emergency or planning to be away from a power source for days - you want to have a battery with a big enough capacity, and that's what 2nd gen Astro E7 delivers with its enormous 25600 mAh. Here is more about it.
After reviewing so many different Anker batteries, I'm already used to their environmentally friendly packaging and typical accessories of a high quality usb to micro-usb cable and storage pouch. But it's always a surprise to see how big the battery turns out to be based on the advertised capacity. You have to realize that increased capacity comes at a price of increased size and additional weight. It's a simple math - higher capacity means more internal battery cells. That is why I never trust some of the budget ebay and other retailers small battery bricks claiming 20k mAh in a footprint of 10k battery. Out of the box, you will definitely feel the weight of E7 at almost 16oz (450g), but it's still manageable thanks to its slick rectangular shape with rounded edges which is easy to handle. With a dimensions of 166 Ã? 80 Ã? 22mm (6.5 Ã? 3.1 Ã? 0.9in) it can actually slip into your front pocket or cargo pants side pocket without a problem, though it will be noticeable. The whole intent of this battery is not to be a small portable back up charger but rather a portable charging power station to give your phones and tablets a boost with up to10 combined charges.
The design is similar to their other 2nd gen E-models, just scaled up in size. You still get a slick piano finish plastic body, very sturdy, no flex. Also a power button on the side to turn the battery on/off, though I found it starts charging automatically as soon as it detects attached device. Another function of power button is to turn built-in white LED by holding and pressing this button. LED functionality is a welcome bonus, especially in emergency situation to use as a portable flashlight or to lit up usb ports so you can connect the cable in the dark. The top of the battery has 4 LEDs to indicate remaining power or to display charging power. These indicate 25% per LED, not as accurate as a regular Astro line with 10-led indicators, but for bulk charging this should be sufficient. I also prefer led indicators over some other batteries that use LCD display which drains the battery. And speaking for that, I can confirm that all of my 2nd gen Anker batteries hold the charge for multiple months when not in use.
E7 model comes with one micro-usb input charging port and 3 full size usb power output ports, each equipped with PowerIQ feature that automatically adjusts current supply per attached device requirement. So if you have an old Android phone, it will source only 1A, while newer phones will get 2A, and your latest iPad will be charging at full 2.4A. Just have to keep in mind that a total combined current can't exceed 4A. Another very important feature is 2A charging input. With a capacity of 25,600 mAh it will take you over a day to charge this battery from empty using a typical 1A charger. Here with 2A wall charger you can juice it up to 100% in approximately 12-13 hours. Also, it's very important to keep in mind that with any battery you have to take into account the convergence efficiency since you are going between 3.7V cells and 5V usb interface. Anker converters are usually very efficient and deliver only 10-12% drop, bringing it closer to 90% efficiency. In comparison, a lot of other batteries are struggling around 80%. With Anker E7 battery you can get about 23,000 mAh of the actual charging capacity.
Overall, I'm always impressed with power products from Anker and consider their external batteries to be among the best. You don't have to take my word for it or to tell me that I'm biased, just search our community for all the positive feedback or look on Amazon where it's #1 best seller in every category with thousands of 5-star reviews. The combination of top quality LG battery cells, durable design, super fast input charging without a need to use proprietary connectors (just a standard micro-usb), bonus of LED light, high efficiency and huge storage capacity, and their 18-months warranty and excellent support - makes this battery my top recommendation, despite a price tag of $80 (just factor in combined cost of smaller capacity batteries).
Here are the pictures.
E7 next to E4
Click to expand...
Click to collapse
Hi,
Great review. I have the same pack at home. I charge my oneplus-two with it. Normally I should get at least 7 charges out of it but I can get only 4 or sometimes 5 at max. Do you have this too?

@CounterC Not really sure what you mean. You used exactly the same battery with the same capacity to charge the same phone 7 times, and not it's only 4-5 times? If that is a case, maybe your phone is discharging too fast while you charging it up, so you get less # charges. Or maybe you were using a different phone or different charger before when you got 7 full charges? To make a true A/B comparison, everything has to be equal

vectron said:
@CounterC Not really sure what you mean. You used exactly the same battery with the same capacity to charge the same phone 7 times, and not it's only 4-5 times? If that is a case, maybe your phone is discharging too fast while you charging it up, so you get less # charges. Or maybe you were using a different phone or different charger before when you got 7 full charges? To make a true A/B comparison, everything has to be equal
Click to expand...
Click to collapse
I have a OnePlus 2 that has 3300mah battery.
So in theory I should be able to charge the device 7,75 times. Unfortunately I get only half of the charges. I explained this to Anker and they just refunded me so now I have a free battery pack [emoji1] [emoji1]. You also see this behavior with your pack?
Sent from my ONE A2003 using Tapatalk

CounterC said:
I have a OnePlus 2 that has 3300mah battery.
So in theory I should be able to charge the device 7,75 times. Unfortunately I get only half of the charges. I explained this to Anker and they just refunded me so now I have a free battery pack [emoji1] [emoji1]. You also see this behavior with your pack?
Sent from my ONE A2003 using Tapatalk
Click to expand...
Click to collapse
It doesn't work like a simple math. Just because battery has 25600 mAh capacity it doesn't mean it will charge your 3300 mAh battery 7 times. This capacity is based on the cells inside, and you have 25.6 Ah at 3.7V. You usb charging port is rated at 5V, and there is a converter at the output from 3.7V to 5V from your battery. Your phone micro-usb port is 5V but internal battery is probably 3.8V, so you have to convert it internally back from 5V to 3.8V. Every time you do the conversion, you loose power due to efficiency. So by the time it gets to charging your phone battery with external battery, you loose a chunk of capacity where instead of 7 times you can charge only 5-6 times. Now, the charging cable is another bottleneck. If you have a thick high quality usb to micro-usb cable with good connector, there is less lose. But if it's an older cable or connector is loose, you - will loose more charging capacity, down to 4-5 charges which you are seeing now.
So, enjoy your free battery

[Review] Choetech QC 3.0 10400 mAh battery pack

Disclaimer: I was sent these items at a heavy discount in exchange for my fair & honest review
Choetech 10400 QC 3.0 Enabled Battery Pack:
Overview
Choetech took their old QC 2.0 battery and made some improvements to it while also adding QC 3.0.
Ports/Charging:
There are a variety of ports offered on this battery which serve different functions. First the battery can be charged on of two ways: you can either use a microUSB cable (like the one included in the box), or a lightning cable if you happen to also have an Apple device. Both cables will allow the battery to be charged at 5V/2.4A; however, I found the battery charges via QC 2.0. I tested it via my multimeter which show the battery drawing ~9V/1.8A which is closer to 16.2 W of power. I’m not sure why the battery doesn’t list this as an input because it certainly takes all of the power.
On the output side you are given the option of using 2 USB-A standard ports. One of these ports will charge at 5V/1A which is also known as QC 1.0, while the second one charges via QC 3.0. The voltage range is variable as is the current. The ranges for the QC 3.0 port are: 5V/3A (15W), 9V/2A (18W), 12V 1.5A (15W). All of these outputs are consistent with the QC 3.0 standard which allows the voltage to step in smaller increments thus reducing the overall heat and increasing charging efficiency.
Design/Build Quality:
This battery has a very nice, solid aluminum housing that really makes it feel nice. The top/bottom edges are chamfered, while the sides are black anodized aluminum. This is the perfect pairing for the HTC 10 given its nice chamfered edge, and similar aluminum construction. I have another Choetech battery pack that is equally well made and feels like a tank. I don’t foresee this battery buckling under normal use, or even some drops given how well made it feels.
To use the battery, you first need to hit the power button that in turn lights up a series of 4 bright LED’s. These LED’s will indicate the current charge left on the battery while also looking great. When you are charging the battery pack the LED indicating its current level of charge will blink as an indication of how much power is currently store in the battery.
What’s in the Box:/B]
-Choetech 10400mAh power bank
-microUSB cable
-Documentation
Charging Multimeter test:
Charging Ports:
Here is breakdown of the voltages/rates the battery can be charged at:
Output: 5V/1A (5W)
QC 3.0 Port: 5V/3A (15W), 9V/2A (18W), 12V/1.25A (15W) [/SIZE]
Battery I/O Rating Pictures
Given the battery’s two output ports, you will be able to charge two devices simultaneously, although I would only use it to charge one at a time personally.
Overall This is a great small QC 3.0 enabled battery pack that will keep everything working on the go. I own battery packs from EasyACC, Choetech, Aukey, and Anker, but this one is still one of my favorites for what it offers. I plan on using this battery to charge my HTC 10 while at school, and on the go in general.

Nice review, I've done a similar thing on amazon, also found the charger to be great. I did a quick charging test and it was averaging around 1500mA, whereas the htc one main plugs charger was 1600mA, so to charge that close to a main plugs socket is great. Specially for a portable charger where you want it charging fast!

Phil750123 said:
Nice review, I've done a similar thing on amazon, also found the charger to be great. I did a quick charging test and it was averaging around 1500mA, whereas the htc one main plugs charger was 1600mA, so to charge that close to a main plugs socket is great. Specially for a portable charger where you want it charging fast!
Click to expand...
Click to collapse
This battery will output the rated (18W) if the phone can handle that much current. I posted a picture in my review using a multimeter to measure the power (16.8W at the moment I took the picture). I don't know what the phones peak input current is, but I know it's higher than than S7 Edges 15.03W input, and Neuxs 6P's 15W. I've seen similar ranges of 15-17W using the stock HTC charger which means this battery is outputting the proper current for the phone to charge as fast as it possible can via the QC 3.0 port.

How many full charges can it deliver to the phone?

Lurien said:
How many full charges can it deliver to the phone?
Click to expand...
Click to collapse
Just over 2 from my experience, but that's 0 to 100 so not bad.
It is damn fast though for a portable charger. For example I've gone from 33% to 100% in a little over an hour

Phil750123 said:
Just over 2 from my experience, but that's 0 to 100 so not bad.
It is damn fast though for a portable charger. For example I've gone from 33% to 100% in a little over an hour
Click to expand...
Click to collapse
Not bad at all.. that's like having 2 spare batteries and change... I'm considering getting this. Thanks for the feedback.

Lurien said:
How many full charges can it deliver to the phone?
Click to expand...
Click to collapse
Phil750123 said:
Just over 2 from my experience, but that's 0 to 100 so not bad.
It is damn fast though for a portable charger. For example I've gone from 33% to 100% in a little over an hour
Click to expand...
Click to collapse
Lurien said:
Not bad at all.. that's like having 2 spare batteries and change... I'm considering getting this. Thanks for the feedback.
Click to expand...
Click to collapse
If you account for the efficiency external batteries have (not very high due to heat losses) the 2 full charges is about right in my experience.

Pilz said:
If you account for the efficiency external batteries have (not very high due to heat losses) the 2 full charges is about right in my experience.
Click to expand...
Click to collapse
Yup when looking at mah of portable batteries I always take off about 30%. Assuming it's good quality that about what you get. I. E in this case 10400mah you get about 7000mah actually usable. Obviously that goes down with time too.

Phil750123 said:
Yup when looking at mah of portable batteries I always take off about 30%. Assuming it's good quality that about what you get. I. E in this case 10400mah you get about 7000mah actually usable. Obviously that goes down with time too.
Click to expand...
Click to collapse
Plus when quick charging you could lose some of the ~7000 you might expect, regardless of that I still find it to work as well as my other 1000mAh battery packs.

Things I miss in your review:
How much does it cost, and how are competitive products placed?
How long does it take to charge the Battery with a QC2.0 Charger?
How much is really inside?
You'd have to use a constant 1.5A load and check How long it lasts... ?
Except from that. Nice review Thanks.

Choetech has stated they're using Samsung Li-Ion cells so they're likely these. I'll crack open mine when I receive it, haven't ordered it yet.
http://gamma.spb.ru/media/pdf/liion-lipolymer-lifepo4-akkumulyatory/ICR18650-26H.pdf
http://lygte-info.dk/review/batteries2012/Samsung ICR18650-26H 2600mAh (Pink) UK.html
-26H is the successor to -26F
http://data.oomipood.ee/kasutusjuhend//ICR18650-26FM.pdf
http://dampfakkus.de/akkutest.php?id=120
http://lygte-info.dk/review/batteries2012/Samsung ICR18650-26F 2600mAh (Pink) UK.html
I personally have these -26H's inside my 4x18650 5V2A power bank case.
They're great cells for indoor use and low current draw (per cell) use.
They'll happily dump over 90% of the specified Whours even at a full 5A discharge. (which is 2600*3.63/1000=9.44Wh)
At a more sane discharge current of 1A/2A they'll be able to provide ~ 99/96% of the specified Whours.
So how much is really inside? Spec sheet says 10200mAh's assuming 0.2C discharge and 2.75V cut-off.
In practice? ~10200-10600mAh's depending on the discharge current. (this is of course fresh cells, capacity will drop over time)
This of course does not take into account the power loss which occurs when you boost the voltage up.
Assuming a nice, above average 90% efficiency inside the power bank you'd be looking at ~9200mAh's.
Then taking into account the voltage stepdown happening inside the phone, let's assume 90% efficiency again and we'd be looking at ~8150mAh's.
Aaand then taking into account the cable loss (- connector losses), let's assume you have an average 26AWG 1 meter cable and you transfer 18W of power at 9V2A, loss is 6%.
We're down to ~7550mAh's.
Saying it can charge a 3000mAh battery twice plays nice with that calculation.
One thing to note though and like I said, great for indoor use but if you look at the spec sheet, you can see the capacity vs temperature table.
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tl;dr if you wish to extract every little ounce of power you can from these cells (or this power bank)
if you go hiking in really cold weather, make sure it stays close to room temp (25C), so not in the outermost compartment of your backpack but neither touching your body which could then warm it up higher than room temp - no es bueno.
if it's a really warm, sunny summer day and you go have a beer outside sitting in the porch, don't leave the power bank in direct sunlight, place it in shade instead
This is pretty much business as usual and has to do with the design of the cell and cathode material used.
Cells [like the -26H] intended for laptops, power banks etc. are going to have different discharge characteristics compared to cells [like INR18650-25R] intended for electric vehicles, power tools and so on.
So it's good that the power bank has an aluminium chassis. It's going to be able to dump some of that heat generated by the boost circuitry in to the air and so on and so forth.
The cells themselves won't really heat up that much. You know, there's 4 of them in there and they are in parallel = current load is being split pretty much equally.
At 3V under load which is pretty close to fully discharged (cut-off = ~2.75V), if the power bank circuitry is prodiving 18 watts of power and drawing 21.6 watts (18+20%) from the 1S4P battery pack because of inefficiencies, it would still be just 7.2A of current total and 1.8A per cell.
Well within the capabilities of these Samsung cells and so low power wise per cell they're not heating up much.

I recently added this one to my arsenal and now prefer it over others I have. I can charge it off anyone's charger i'm with on longer trips so cable management is nill. Love the fact you can tell it's in qc mode versus normal charge mode.

Just recently got this power bank for my hTc 10 - as from my experience 10Ah looks impressive on the computer screen - but in real life we actually need 20Ah backup battery .. ?
Spoiler
And it states that output is 12V x 1.5A what actually implies 18W... ?
Sent from quite brutal hTc 10 ..

dottat said:
I recently added this one to my arsenal and now prefer it over others I have. I can charge it off anyone's charger i'm with on longer trips so cable management is nill.
Click to expand...
Click to collapse
Well, not exactly nil, right? You can charge from micro-usb or from lightning, which is a great addition, but you can't actually charge from the cable you're most likely to be carrying with your HTC 10, which is a USB C cable, right? I looked at the description on Amazon, and thought that was an interesting omission.

Andyw2100 said:
Well, not exactly nil, right? You can charge from micro-usb or from lightning, which is a great addition, but you can't actually charge from the cable you're most likely to be carrying with your HTC 10, which is a USB C cable, right? I looked at the description on Amazon, and thought that was an interesting omission.
Click to expand...
Click to collapse
It can be charged via a microusb cable that is included. Since they are as common as can be I don't see how that would be an issue. I have piles of them laying around, spare one in my car etc.. I know it's not ideal to have more than one type of cable, but I use them to charge my S7 Edge, Bose QC 20's , LG Tone Platinum's etc.. that's why I personally have them just about everywhere. I also have a time of Type-C, C-C/A-C cables because of my Nexus 6P. Ideally I would like 4 type c poets for in/out but no one makes anything close yet.

Pilz said:
It can be charged via a microusb cable that is included. Since they are as common as can be I don't see how that would be an issue. I have piles of them laying around, spare one in my car etc.. I know it's not ideal to have more than one type of cable, but I use them to charge my S7 Edge, Bose QC 20's , LG Tone Platinum's etc.. that's why I personally have them just about everywhere. I also have a time of Type-C, C-C/A-C cables because of my Nexus 6P. Ideally I would like 4 type c poets for in/out but no one makes anything close yet.
Click to expand...
Click to collapse
I never suggested it would be hard to find a cable to charge the battery pack.
But dottat wrote that cable management issues were nil, so I was merely pointing out that for those of us with HTC 10s that really isn't quite the case, since if we want to travel with a single cable, the single cable we are going to travel with -- a USB C cable -- can't charge the battery. This means bringing two cables, at a minimum.
This was not a huge complaint or indictment of the product. I was just making a point. The product would be even better if it could charge via a USB C cable.

Andyw2100 said:
I never suggested it would be hard to find a cable to charge the battery pack.
But dotat wrote that cable management issues were nil, so I was merely pointing out that for those of us with HTC 10s that really isn't quite the case, since if we want to travel with a single cable, the single cable we are going to travel with -- a USB C cable -- can't charge the battery. This means bringing two cables, at a minimum.
This was not a huge complaint or indictment of the product. I was just making a point. The product would be even better if it could charge via a USB C cable.
Click to expand...
Click to collapse
I completely agree, unfortunately there are only a handful of battery packs that support QC 3.0 and even fewer that offer Type-C (if any yet) on top of that. The interesting part is their QC 2.0 version has a Type-C port to charge the battery along side the microusb. I'm not sure why they changed that (maybe to appeal to a larger crowd), but it's odd nonetheless. I can post a picture of it later today since its 0103 right now so the lighting wouldn't be ideal to see it.

Andyw2100 said:
...dottat wrote that cable management issues were nil, so I was merely pointing out that for those of us with HTC 10s that really isn't quite the case, since if we want to travel with a single cable, the single cable we are going to travel with -- a USB C cable -- can't charge the battery. This means bringing two cables, at a minimum.
Click to expand...
Click to collapse
But within a large company someone is definitely with iPhone - what somehow suggests carrying one more cable.. ?
I opted to carry my original hTc 10 Type C cable and a small interface which converts Type C into the lightning connector.. ?
Sent from quite brutal hTc 10 ..

jauhien said:
But within a large company someone is definitely with iPhone - what somehow suggests carrying one more cable.. ?
I opted to carry my original hTc 10 Type C cable and a small interface which converts Type C into the lightning connector.. ?
Sent from quite brutal hTc 10 ..
Click to expand...
Click to collapse
They make one that charges via Type-C as I mentioned earlier; however, it uses QC 2.0 as opposed to QC 3.0

Has anyone compared this Choetech 10400 QC3 (currently unavailable on Amazon) with the Anker 20000 QC3? Pros? Cons?