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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.

Review of Anker Astro 3 (2nd gen) 12000 mAh external battery w/pics!!!

This is a review of Anker Astro 3 (new 2nd gen) 12000 mAh external battery: http://www.ianker.com/product/79AN7904-BA
*** The Review of the Updated version was posted here: http://forum.xda-developers.com/showpost.php?p=51836263&postcount=62
***
Yes, another external battery. No, this one is like nothing I have ever tested from Anker or anybody else. It's not a surprise Anker became one of my favorite companies to review new products from because they are constantly introducing something new and/or improved. That is the only way to stay on top of the game and to earn the top rating of your customers.
First of all, even with it's 12000 mAh capacity, this new 2nd gen Astro shrank up in size down to 110 mm x 83 mm x 26 mm which fits very comfortably and feels very nice with its soft touch rubbery finish in your hand. At close to 10 oz in weight you will feel it for sure in your pocket, although it's slick design is very portable and with included mesh pouch is easy to carry around in your bag/purse/backpack or even pants pocket, as long as you are not wearing skinny jeans In contrast to most of the today's external batteries with dual output, Astro 3 comes with 3 independent full size usb outputs that deliver a whooping 4A of combined current. I checked it by charging Note 2, S4, and Nexus 7 simultaneously and was able to confirm that right on a dot. N2 was charging at about 2A, S4 at about 1A, and N7 at about 1A as well. I was actually timing and monitoring the percentage of battery change, not just relying on Current Charge app. These 3 usb charging outputs are actually partitioned into one Smart output (intended for Apple devices and other android devices) and two Universal outputs which are specifically designed to charge Android devices at maximum speed. There is some custom circuit which determines max speed and optimizes output correspondingly. I also noticed the safety nature of this circuit prevented me from charging both N2 and S4 at 2A each from Universal outputs where N2 was charging at 2A and S4 at 1A, leaving 1A for Smart output, thus confirming it's not a bulk current sharing between all 3 ports. The input port, micro-usb, for charging Astor 3 is actually a fast 1.5A input which is great since it charges this external battery at 1.5x times faster rate.
While you charging the battery itself or using to charge other devices, another huge improvement in the design is a circular 10-segment indicator with granularity of 10%. You no longer have to rely on a typical 4-segment led. This one will give you a more precise reading, although it might take you a little while to get used to figuring out on a spot the exact percentage by counting segments before light times out. Once the light turns off, it's a clean surface design with no leds or buttons. So how do you turn it on or verify led count? Yet another cool innovation, just do a shake of the battery and indicator circle turns on to reveal number of active segments. I really like that motion activated switch, makes it very unique. But trust me, it's not the most unique part of this new Astro 3 design. As I mentioned in a number of my previous reviews, the labeled capacity of the battery is not what you actually get. It's the capacity of the cells inside of external battery when it has to be converted to 5V usb interface at the output and then back from 5V to 3.7V inside of the phone. During this conversion ALL external batteries loose anywhere between 30%-35% of its capacity. Well, this new 2nd gen Astro 3 is optimized to a much higher efficiency. I have tested it and can confirm it provides the actual charging capacity of 10,044 mAh, which means a loss of only 16%!!! Basically, the internal battery circuit has been optimized to provide a more efficient output. I have tested a lot of external batteries, and this is the first one I have seen at such high efficiency.
Overall, I was very impressed with a design and features of this battery, especially with how efficient it's output. Currently offered for $49.99 on Amazon its a great value where it provides the actual capacity output equal to other more expensive batteries labeled at around 14000 mAh. With a high output efficiency, 4A of total combined charging current, triple output, and motion activated 10-segment led indicator - I highly recommend it!
Here are the pictures.
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Someone just pointed out to me Anker has back 2 school sale, with Astro 3 now for $45.99. Here is a link: http://www.ianker.com/adpage.php?act=us
I also been asked if Smart port will charge iPad 4 at full 2.4A speed. I'm checking into this and will post an update as soon as I find out.

I got an anker too, but the e4. Seems like i can only reach 1.8A when i'm using the cable provided by Anker and not the Sammy OEM cable..

Ev0d3vil said:
I got an anker too, but the e4. Seems like i can only reach 1.8A when i'm using the cable provided by Anker and not the Sammy OEM cable..
Click to expand...
Click to collapse
If you referring to 1.8A per Galaxy Charging Current app, that's an approximation anyway. Unless if you are rooted and using something else where in an identical setup where you exchange cables and see 1.8A in one case and 2.0A in another case?

Looks great. I would buy it in a second, if it was not so thick. I would not mind a longer wider power bank. A power bank that was 5.7 *4.5*.6 inches would have roughly the same volume as the 2nd generation Astro 3. In other words, the same thickness as the Astro 3E.
PS The volume of the Astro 3E is 9.41 versus the Astro 2nd generation at 14.52. The power bank increased in size more than in power. The Astro 2nd generation is 54 percent larger.

What cable are you using for the note 2? Now i'm not getting the 1800mah charge with the anker e4. Ugh.

Explore3 said:
Looks great. I would buy it in a second, if it was not so thick. I would not mind a longer wider power bank. A power bank that was 5.7 *4.5*.6 inches would have roughly the same volume as the 2nd generation Astro 3. In other words, the same thickness as the Astro 3E.
PS The volume of the Astro 3E is 9.41 versus the Astro 2nd generation at 14.52. The power bank increased in size more than in power. The Astro 2nd generation is 54 percent larger.
Click to expand...
Click to collapse
But it also increase in capacity and efficiency, so you can also look at it as volume per capacity E3 probably had a capacity of around <7k mAh (after 30% de-rating efficiency). With Astro3 you start with 12000 mAh versus 10000 mAh and have at least 80% average efficiency, plus get 3 outputs with one being smart output used for any iCrap including 2.4A iPad 4 (which btw is confirmed). Also, 10% indicator is way cooler. Just imho, a bit of thickness increase is OK because length is a deal breaker for pocket-ability. And yeah, I'm talking about batteries
If you want absolutely the slimmest possible battery, checkout review of Astro Slim3 6000 mAh I just posted here: http://forum.xda-developers.com/showthread.php?t=2388894 - 12mm in thickness, that is insane!!! and you get 80% efficiency as well with a built in micro-usb cable.

Can't buy this thing on Amazon as it seems Anker for whatever reason has had all their products yanked. Anker sells it on Ebay in their Ebay Anker Store as well .....but they want $199.96 for it! They say it's that high because stock is low. Seems strange to me. I would love to know what is up between Anker and Amazon.
http://www.ebay.com/itm/Anker-Astro..._Cell_Phone_PDA_Batteries&hash=item4d0f5d413d

Old MuckenMire said:
Can't buy this thing on Amazon as it seems Anker for whatever reason has had all their products yanked. Anker sells it on Ebay in their Ebay Anker Store as well .....but they want $199.96 for it! They say it's that high because stock is low. Seems strange to me. I would love to know what is up between Anker and Amazon.
http://www.ebay.com/itm/Anker-Astro..._Cell_Phone_PDA_Batteries&hash=item4d0f5d413d
Click to expand...
Click to collapse
I asked them the same question. Apparently something got messed up with US listing of all of their products and they are working with Amazon to fix it. I had someone from Canada asking me questions about Anker, and I see all of their products are listed fine on Amazon in Canada, UK, Germany, and everywhere else internationally. Something got messed up with US listing and I confirmed with Anker they are working as soon as they can with Amazon to fix it.

vectron said:
I asked them the same question. Apparently something got messed up with US listing of all of their products and they are working with Amazon to fix it. I had someone from Canada asking me questions about Anker, and I see all of their products are listed fine on Amazon in Canada, UK, Germany, and everywhere else internationally. Something got messed up with US listing and I confirmed with Anker they are working as soon as they can with Amazon to fix it.
Click to expand...
Click to collapse
Just seems strange to me...Amazon is always very good about fixing technical issues and this has been going on for days. In any event none of that justifies charging 200 bucks for the Astro 3 on their Ebay store....low stock or not.
I've never had anything but good experiences with Anker, FWIW.

Old MuckenMire said:
Just seems strange to me...Amazon is always very good about fixing technical issues and this has been going on for days. In any event none of that justifies charging 200 bucks for the Astro 3 on their Ebay store....low stock or not.
I've never had anything but good experiences with Anker, FWIW.
Click to expand...
Click to collapse
I agree! But I actually seen someone else do that before. I forgot which product it was, but we had a reply here on XDA to one of the posts jocking they misplaced a decimal point. Then, someone else posted later they just jacked up the price to keep the listing "alive" while they were out of stock and obviously nobody would buy it for the price 100x higher than original. I guess just another trick...

vectron said:
I agree! But I actually seen someone else do that before. I forgot which product it was, but we had a reply here on XDA to one of the posts jocking they misplaced a decimal point. Then, someone else posted later they just jacked up the price to keep the listing "alive" while they were out of stock and obviously nobody would buy it for the price 100x higher than original. I guess just another trick...
Click to expand...
Click to collapse
All I know for sure is that I would like to order this damn thing already. Have not been able to order anything from Anker thru Amazon for almost a week now.

vectron said:
I asked them the same question. Apparently something got messed up with US listing of all of their products and they are working with Amazon to fix it. I had someone from Canada asking me questions about Anker, and I see all of their products are listed fine on Amazon in Canada, UK, Germany, and everywhere else internationally. Something got messed up with US listing and I confirmed with Anker they are working as soon as they can with Amazon to fix it.
Click to expand...
Click to collapse
I gotta say, I'm getting a little worried about this Amazon "problem" . . . we're heading into one week with no Anker products on Amazon and I just don't see a messed-up listing taking this long to remedy. I finally got through to customer service today because I need a bluetooth speaker and I wanted to pick up their BT 4.0 speaker before I head on vacation. They have no idea how long this is going to last and the CSR I spoke to said, in so many words, that I might want to purchase my speaker elsewhere. Understand, I informed her I was under a time constraint so that obviously affected her response, but Anker is getting excoriated on their FB page. I hope everything is rectified soon, because my experience with this company has been spectacular.

Thanks for the review. I'm torn between trying to wait for this one to become available again or to bite the bullet and order the old 3 for $5 more.

CocheseUGA said:
Thanks for the review. I'm torn between trying to wait for this one to become available again or to bite the bullet and order the old 3 for $5 more.
Click to expand...
Click to collapse
First of all, I just saw that all the Anker products are back online on Amazon!
But, I also see that Astro 3 (2nd gen) is on back order due to demand. In my opinion, wait until its available. Why buy old technology when you can get unit with a higher capacity, more USB outputs, better efficiency, and new indicator?
... UPDATE... It is sold out on US Amazon, but should be back in stock in 1 week.
In general, and this doesn't refer just to Anker but any other product/vendor I have reviewed. If anybody has a question for a vendor and can't get an answer right away - let me know because I receive review samples directly from their marketing department and can get in touch quicker to get you an answer.

Hi, i'm getting a really slow charge with the Anker battery. Are you rooted and flashed with Perseus? I can't seem to get a 1.8A charge on any power bank. Stock here btw.

Ev0d3vil said:
Hi, i'm getting a really slow charge with the Anker battery. Are you rooted and flashed with Perseus? I can't seem to get a 1.8A charge on any power bank. Stock here btw.
Click to expand...
Click to collapse
Which battery and what usb cable are you using? I'm all stock, not rooted. Either Anker or any other brand I have tested, if they rate output to 2 - I always see 1.8A charging and can confirm it by timing and watching % charge. But I do use either oem usb cable or usb cable from my ue Boom or monoprice cables. No matter how great your battery, the cable will be your bottleneck if its not true 2A cable. Plus I have tested and can confirm that with a number of external batteries if you are charging from "apple" designated port or port rated at 1A - they put some current limiting to keep it capped.

vectron said:
Which battery and what usb cable are you using? I'm all stock, not rooted. Either Anker or any other brand I have tested, if they rate output to 2 - I always see 1.8A charging and can confirm it by timing and watching % charge. But I do use either oem usb cable or usb cable from my ue Boom or monoprice cables. No matter how great your battery, the cable will be your bottleneck if its not true 2A cable. Plus I have tested and can confirm that with a number of external batteries if you are charging from "apple" designated port or port rated at 1A - they put some current limiting to keep it capped.
Click to expand...
Click to collapse
Tried with the cable that came with the phone, stock, sometimes the charge drops to below 1000ma on the 2A port. Tried with a HTC cable. Same issue. Also tried with the cable that came with the anker, same thing. Am using an Anker E4 so i believe their build quality is more or less the same right?
Which monoprice cable are you using? Can you give me a link on amazon? Guaranteed true 2amp cable?

http://www.amazon.com/gp/aw/d/B003L18S0E/

vectron said:
http://www.amazon.com/gp/aw/d/B003L18S0E/
Click to expand...
Click to collapse
Thanks! so the stock cable isnt a true 2 amp cable as compared to this? From what i see, its gold plated and ferrite?

Best external battery.

Hi,
I'm seeking for an external battery than can charge my phone two times from 0% to 100%.
I have seen the anker astro slim3 6000mAh, I like it because it is quite powerful and slim, very portable.
http://www.ianker.com/product/79AN7909-BA
In any case I need a quality battery that don't loose charge if not used for a period of time.
In the anker site I read reviews where customers complains about the fact that the battery loose charge if not used just after few days.
I want a battery that stays fully charged for 15 days also if not used, do you know a battery like this?

sblantipodi said:
Hi,
I'm seeking for an external battery than can charge my phone two times from 0% to 100%.
I have seen the anker astro slim3 6000mAh, I like it because it is quite powerful and slim, very portable.
http://www.ianker.com/product/79AN7909-BA
In any case I need a quality battery that don't loose charge if not used for a period of time.
In the anker site I read reviews where customers complains about the fact that the battery loose charge if not used just after few days.
I want a battery that stays fully charged for 15 days also if not used, do you know a battery like this?
Click to expand...
Click to collapse
As I replied to you in N2 thread, hardly any vendor manufacturers their own battery and rather buy and sell it re-branded. And you will also find some bad "apples" in every batch. Anker has thousands of reviews on Amazon, average rating of 4.5-4.75, and is #1 selling external battery brand on amazon with 18-month warranty. I have every single battery they're selling and reviewed them all. Slim2/3 will hold the charge for awhile, and also their latest 2nd gen Astro series is by far superior to all of their previous models. If you want something portable, 2nd gen Astro will be great with 6000 mAh, or you can go to a bigger double output Astro 2 with 9000 mAh, or triple output Astro 3 with 12000 mAh. Slim 3 is their latest slimmest one which I just checked on Amazon is out of stock due to popularity. I still use Slim 2 and 3 and always encourage my wife to carry it with her in the purse to use when her phone goes down.

vectron said:
As I replied to you in N2 thread, hardly any vendor manufacturers their own battery and rather buy and sell it re-branded. And you will also find some bad "apples" in every batch. Anker has thousands of reviews on Amazon, average rating of 4.5-4.75, and is #1 selling external battery brand on amazon with 18-month warranty. I have every single battery they're selling and reviewed them all. Slim2/3 will hold the charge for awhile, and also their latest 2nd gen Astro series is by far superior to all of their previous models. If you want something portable, 2nd gen Astro will be great with 6000 mAh, or you can go to a bigger double output Astro 2 with 9000 mAh, or triple output Astro 3 with 12000 mAh. Slim 3 is their latest slimmest one which I just checked on Amazon is out of stock due to popularity. I still use Slim 2 and 3 and always encourage my wife to carry it with her in the purse to use when her phone goes down.
Click to expand...
Click to collapse
I would like to understand if it is bad apples or the only users who noticed the problem.
Have you ever tried to charge your astro and leave it for 10 days? What are the charge after 10 days?

sblantipodi said:
I would like to understand if it is bad apples or the only users who noticed the problem.
Have you ever tried to charge your astro and leave it for 10 days? What are the charge after 10 days?
Click to expand...
Click to collapse
I charge and use them. Ok, have Slim 3 right now fully charged. Will leave it alone and come back to this thread in a week or so

vectron said:
I charge and use them. Ok, have Slim 3 right now fully charged. Will leave it alone and come back to this thread in a week or so
Click to expand...
Click to collapse
I will wait. I think that very few people will use the battery pack every day, but as me, they would carry the battery pack just in case is needed.
If it discharge after three days it will be unuseful for most people.

sblantipodi said:
I will wait. I think that very few people will use the battery pack every day, but as me, they would carry the battery pack just in case is needed.
If it discharge after three days it will be unuseful for most people.
Click to expand...
Click to collapse
Since I had both Slim 2 and 3 fully charged since yesterday, it will be a good test to let you know how long it will take for any leakage voltage.
Btw, I do realize you are on a mission (after reading one comment out of thousands for all the batteries they sell?!?, not to mention tenths of thousands of other positive comments never left by others because people usually like to complain on-line rather then praise), but just speaking from a personal experience of reviewing over a hundred of accessories just in the last half a year or so - I research every product and company before I approach them asking for samples to review. So for a company to be #1 seller on amazon with thousands of 4.75 star reviews while offering 18-months warranty - simply means they have the best product which people like, and overall its a good working product with a decent quality control. If there is a problem with a design of a product - every single piece will fail. If there is a problem with a bad production batch - everything will be replaced under warranty. If there is a massive failure of products - company will go out of business replacing a lot of faulty products under warranty. Its a common sense. When it comes to electronic products, any company that claims 100% yield is lying, especially if you contract other companies to manufacturer for you or you license other products and sell under re-branded name.
Btw, a simple question. Considering 18-months warranty and hassle free return from amazon (depending on a country where you live), why wouldn't you just buy this $30 battery to try it out yourself and if it doesn't work write your negative comment about it? Should be simple enough.

My advice for you
In your case, I would suggest you to get a larger capacity charger that can charge 3 times your phone. Any charger is gonna lose the power even if you put it aside for a while. I have bought the Anker slim as you did before and I am happy with it. But since I'm getting more electronic devices, I require one with much more juice. My friend once showed me his RavPower 10400mAh and I checked that it has a reasonably price for me. Compared with Anker, I would be even more willing to have another charger from RavPower as they've a cheaper price but even larger capacity.

NikJe said:
In your case, I would suggest you to get a larger capacity charger that can charge 3 times your phone. Any charger is gonna lose the power even if you put it aside for a while. I have bought the Anker slim as you did before and I am happy with it. But since I'm getting more electronic devices, I require one with much more juice. My friend once showed me his RavPower 10400mAh and I checked that it has a reasonably price for me. Compared with Anker, I would be even more willing to have another charger from RavPower as they've a cheaper price but even larger capacity.
Click to expand...
Click to collapse
I abandoned the idea of buying an anker slim, the output of the slim version is 1A and I want 2A at least.
It will take forever to charge a phone with a 1A output.
For this reason I can choose between this:
Anker 2nd gen Astro 2 9000mAh 2A output
Anker Astro 3E 10000mAh 3.1A output
RAVPower 10400mAh 2A output.
can't understand why Anker sells the 2nd gen as something new while the 3E has more features and is cheaper.

sblantipodi said:
I abandoned the idea of buying an anker slim, the output of the slim version is 1A and I want 2A at least.
It will take forever to charge a phone with a 1A output.
For this reason I can choose between this:
Anker 2nd gen Astro 2 9000mAh 2A output
Anker Astro 3E 10000mAh 3.1A output
RAVPower 10400mAh 2A output.
can't understand why Anker sells the 2nd gen as something new while the 3E has more features and is cheaper.
Click to expand...
Click to collapse
Slim 3 charges my Note 2 at 2A charging speed. Doesn't matter what they put on the label lol!!!
All of their batteries will output 2A if your phone can charge at that speed. Regarding capacity versus value, might as well go with Anker E5: http://www.amazon.com/gp/product/B00D5VAYRU/ - 15000 mAh for $49.99 and includes led flashlight (I reviewed that one as well).
The difference between original Anker products and 2nd gen is that new ones have 80% efficiency while old ones is closer to 70%-75%. Every other external battery out there is close to 70% efficiency. When they tell you capacity on the label, its a capacity of internal 4.7V battery inside. That has to be converted to 5V through usb output and during that conversion typically all ext batteries loose 30% of capacity. 2nd gen Anker has a more efficient circuit which looses only 20%. Plus, 2nd get has 10-led power indicator to give you a more accurate reading of charging or remaining power. Their original stuff and slim, as well as every other vendor out there, uses 4-led indicator which gives you accuracy in 25% increments while 2nd gen gives you 10% increments.
Also, for your information, "NikJe" works for RAVPower. I tested a number of their products and they are all good as well. Nothing against them
BTW, just checked both Slim 2 and Slim 3 since it has been 2 days from charging them up to full, they are still at 100% with all 4 leds fully lit up.

vectron said:
Slim 3 charges my Note 2 at 2A charging speed. Doesn't matter what they put on the label lol!!!
All of their batteries will output 2A if your phone can charge at that speed..
Click to expand...
Click to collapse
there are many people who says that slim3 charges ipad really slows, this clearly means that the label is correct, it can't charge at 2A, not all devices at least.

sblantipodi said:
there are many people who says that slim3 charges ipad really slows, this clearly means that the label is correct, it can't charge at 2A, not all devices at least.
Click to expand...
Click to collapse
iPad uses 2.4A, not 2A. Of course it will not charge iPad at full speed. Anker Astro 1/2/3 2nd gen "smart" output can charge it at 2.4A, the latest iPad at full charging speed.
Gee, you don't give up, uh? Just took these pictures for you.
My Note 2 next to Slim 2 and Slim 3 (slim 3 connector is modified, I trimmed the rubber off to fit with my case).
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Using Galaxy Charging current app, here is charging from Slim 2 (Max current number is a rating it charges at, 1800 mA always shown for max 2A rating).
And here is using Slim 3 (I couldn't zoom in to display with the whole battery shown):
I don't know what else to tell you, and a bit puzzled with your persistence to paint Anker as inferior product. You can trust my unbiased opinion because I review a lot of batteries, gadgets, accessories, etc. I do that as part time hobby, and as you can see from my post and "thanks" stats people trust my opinion. I'm telling you how it is, and include pictures to back up my write ups. If you don't believe me, it's your choice to buy something else or to buy any of the products I review and come back with your own reply-review to let everybody know if you agree or disagree with my write up.

vectron said:
iPad uses 2.4A, not 2A. Of course it will not charge iPad at full speed. Anker Astro 1/2/3 2nd gen "smart" output can charge it at 2.4A, the latest iPad at full charging speed.
Gee, you don't give up, uh? Just took these pictures for you.
My Note 2 next to Slim 2 and Slim 3 (slim 3 connector is modified, I trimmed the rubber off to fit with my case).
Using Galaxy Charging current app, here is charging from Slim 2 (Max current number is a rating it charges at, 1800 mA always shown for max 2A rating).
And here is using Slim 3 (I couldn't zoom in to display with the whole battery shown):
I don't know what else to tell you, and a bit puzzled with your persistence to paint Anker as inferior product. You can trust my unbiased opinion because I review a lot of batteries, gadgets, accessories, etc. I do that as part time hobby, and as you can see from my post and "thanks" stats people trust my opinion. I'm telling you how it is, and include pictures to back up my write ups. If you don't believe me, it's your choice to buy something else or to buy any of the products I review and come back with your own reply-review to let everybody know if you agree or disagree with my write up.
Click to expand...
Click to collapse
hey I don't persist in paint anker as inferior I say what they write on their site.
http://www.ianker.com/product/79AN7909-BA#ptop
on their site they wrote that anker small 3 has two 1A ports. if they are wrong in writing specs on the official site also is not my problem in painting anker as inferior.

sblantipodi said:
hey I don't persist in paint anker as inferior I say what they write on their site.
http://www.ianker.com/product/79AN7909-BA#ptop
on their site they wrote that anker small 3 has two 1A ports. if they are wrong in writing specs on the official site also is not my problem in painting anker as inferior.
Click to expand...
Click to collapse
I will forward to them this thread. I'm sure they will be happy to receive free publicity we generated for them lol!!!

vectron said:
I will forward to them this thread. I'm sure they will be happy to receive free publicity we generated for them lol!!!
Click to expand...
Click to collapse
Can't understand why they understimate their products if they are able of 2A

sblantipodi said:
Can't understand why they understimate their products if they are able of 2A
Click to expand...
Click to collapse
I wonder if its for safety reason? I know they have over-current and over-voltage protection built in. With slim design you have less air circulation inside of the case to cool down electrical components. With other thicker cases it will run cooler. But either way, it's definitely capable of charging it at high speed.

flynnchen said:
Anker and RAVPower are all good in its own way. Hard to say which is better.
Click to expand...
Click to collapse
Flip a coin, either side wins

sblantipodi said:
Hi,
I'm seeking for an external battery than can charge my phone two times from 0% to 100%.
I have seen the anker astro slim3 6000mAh, I like it because it is quite powerful and slim, very portable.
http://www.ianker.com/product/79AN7909-BA
In any case I need a quality battery that don't loose charge if not used for a period of time.
In the anker site I read reviews where customers complains about the fact that the battery loose charge if not used just after few days.
I want a battery that stays fully charged for 15 days also if not used, do you know a battery like this?
Click to expand...
Click to collapse
Is there even such a battery that can produce these results?

It has been 10 days since I charged Slim 2 and Slim 3 to full charge. Just checked their status and each one has 3 leds lit up which means it still has charge of anywhere between 75% and 85%. This is pure standby time with an exception of one time brief use of each just to check charging current. I will post an update in a few weeks again, I'm sure both will still have some juice left

i have galaxy s2 oem charger and galaxy s4 oem charger the galaxy s4 charger is 4 time faster than the galaxy s2 charger i don't know why !!

medo2_0 said:
i have galaxy s2 oem charger and galaxy s4 oem charger the galaxy s4 charger is 4 time faster than the galaxy s2 charger i don't know why !!
Click to expand...
Click to collapse
What is a current rating on each? S4 charger will have 2A (2000 mA) versus S2 being probably at least 1A or slower, not to mention S2 is an older one and they get de-rated after awhile. If your phone can charger at 2A rate (like Note 2 or S4 or Note 3) it will charge at full speed using 2A charger, but if you use 1A charger it will charge at 1/2 speed. If you plug it to USB port of laptop which can only supply 500mA, it will charge at 1/4 speed.

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 of Anker PowerCore+ Mini 3350 mAh lipstick battery w/lots of pics!!!

This is a Review of Anker PowerCore+ Mini 3350 mAh �lipstick� external battery. http://www.ianker.com/product/A1105011.
When it comes to external batteries, bigger capacity doesn�t necessary mean a better battery. Yes, we always look for the best price/performance/capacity ratio, but with batteries you need to figure out the capacity per need ratio. When you are at home and need a backup battery, get the largest capacity you can find � there is no need to drag it around so it could be as heavy as it comes. When you are traveling, maybe a compromise of a smaller capacity in exchange for a lighter weight is the better way to go. But for everyday portable use where you need an emergency backup � the smallest footprint with the largest capacity you can find is what you should be looking for. Even so Astro is already small and portable, it will be hard to beat Anker�s latest �lipstick� PowerCore+ Mini with 3,350 mAh.
I know some will say capacity of only 3,350 mAh?!? We get spoiled quickly with 10,000 mAh or 20,000 mAh external batteries, but when you take a look at this tiny 95 x 23 x 23mm (3.7 x 0.9 x 0.9in) size lipstick cylinder in a quality aluminum drop-tested shell with a weight of only 3oz � you will really appreciate size/capacity ratio. On top of that, it comes with Anker�s typical drawstring small storage pouch and a quality usb to micro usb cable. And since it�s available in a variety of colors, including some colorful pink and blue finishes, this battery can also be used as a �fashionable� accessory for the ladies.
The design itself is very minimalistic and elegant. I already mentioned about aluminum shell finish which feels very solid in your hand and gives you extra peace of mind if you accidentally drop it. The shell covers the entire cylinder in one solid piece, leaving only the top open where you have full size USB port to connect cable to your phone or tablet, micro USB port to charge this battery, and a small led/power button. To display the charging capacity, led has 3 colors to indicate: green 50%-100%, yellow 20%-50%, and red 5%-20%. It�s obviously not as accurate as Astro�s 10-led indicator with 10% increments, but considering this small footprint � it works fine. Plus keep in mind, most of the time you will probably get one or two full charges from this battery, so accuracy is not as important.
In terms of performance, Anker mentions it uses a premium Panasonic cell which is always a plus. The battery itself has a rather high efficiency of almost 92% (confirmed) which means you still get a solid 3,080 mAh of charging from this battery after internal 5V conversion through usb port. Most of the other lipstick batteries are typically in 80% efficiency range due to less efficient converters. The charging of the battery itself will not be lighting fast since input port is 5V at 1A, so expect a little over 3hrs of charging from empty. The ext charging port is only able to supply 1A of output power at 5V, though I actually confirmed it to provide 1.2A with my Note 4. It does offer PowerIQ intelligent charging current adjustment, but it doesn't matter since you are not going between 1A, 2A, or 2.4A charging speed. Most likely it will run around 1A-1.2A which is OK for emergency charging when you are on a go.
Overall, if you are looking for a super portable external battery for your phone or tablet, and need the smallest compact footprint to put it in your shirt pocket or a purse without adding too much weight, and still want to have enough capacity for emergency fast charging � this new Anker PowerCore+ Mini might be the one for you. 3,350 mAh is a pretty good capacity for on-the-go emergency charging, and if you factor in high efficiency, quality build with aluminum solid shell, included travel pouch and usb cable, and Anker�s 18-months warranty � this is one cool gadget to keep with you in a pocket for under $20.
Here are the pictures.
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I have two of these, neither achieves anywhere near that efficiency with either Galaxy S4 or Note 5, with the cable provided, which the phone entirely turned off.
Both provide around 2300-2500mAh effectively, that is efficiency net of battery, powercircuit, cable and phone charging circuit losses, or around 70%.
Anker officially also confirms an efficiency of around 70% or, quote: "an almost one full charge to a Galaxy S6" (< 2550mAh), respectively.
So I am not just making this up. I tested this with an inline USB meter as well as with Battery Monitor Widget.
In their English that is almost one full charge for my Galaxy S4, or about 3/4 charge for my Note 5 (phones off while charging, duh!)
This is still a handy little thing to have, but Anker is very shy to openly say how efficient their devices are. All about that sale and Amazon tags after all.

kaefers said:
I have two of these, neither achieves anywhere near that efficiency with either Galaxy S4 or Note 5, with the cable provided, which the phone entirely turned off.
Both provide around 2300-2500mAh effectively, that is efficiency net of battery, powercircuit, cable and phone charging circuit losses, or around 70%.
Anker officially also confirms an efficiency of around 70% or, quote: "an almost one full charge to a Galaxy S6" (< 2550mAh), respectively.
So I am not just making this up. I tested this with an inline USB meter as well as with Battery Monitor Widget.
In their English that is almost one full charge for my Galaxy S4, or about 3/4 charge for my Note 5 (phones off while charging, duh!)
This is still a handy little thing to have, but Anker is very shy to openly say how efficient their devices are. All about that sale and Amazon tags after all.
Click to expand...
Click to collapse
Are you sure you are not talking about PowerCore Mini, rather than their latest PowerCore+ Mini? "+" is an updated version.

Yes, Anker PowerCore+ mini 3350mAh. I got one for my Note 5 thinking should be a full charge, but wasn't the case.
After that, I went to the reviews on Amazon and also http://www.ianker.com/support/A1104041, they actually say it's 70-80%, mine was more around 70-75% with the Note 5 off while charging.
It's not Anker-specific though, Anker is doing relatively well, Aukey 5000mAh is only around 65%...
Also, either way, for 10 GBP it's really not bad. Just love how 90% of customers incl myself buy something without knowing better b/c it's all in the fineprint.

The quote from ianker website:
The efficiency of this powercore is around 70%-80%. The internal circuit board is 92% efficient, accounting for power lost through circuit heat and voltage conversion, which is up to 5% above the industry average. Energy is also lost within the charging cable and the device being charged (approximately 15-20%). Additionally, the efficiency can be affected by the cable length and the age of the device being charged.
Where the efficiency of conversion under ideal condition is over 90%. They trying to be conservative saying overall it could drop to 70%-80% depending on your phone model, internal battery age, and the most important - cables which can overheat (if they are cheap thin with loose connection). In one of my reviews testing battery charge monitor and different cables I demonstrated variation of different cables which could affect efficiency as well.
But anyway. This lipstick battery is for emergency boost (not a reliable full charge, but a boost to keep you afloat ) and doesn't even allow a fast charging. If you really need a backup, get a higher capacity more advanced battery from Anker with PowerIQ chip.

vectron said:
the most important - cables which can overheat (if they are cheap thin with loose connection)
Click to expand...
Click to collapse
And what about a cable supplied with this device?

Bought one yesterday, did 2 full charge-uncharge cycles:
1) Razr Maxx XT910 +35% (65->91%) and Nexus 9 +12% (27->40%)
2) Nexus 9 +33% (27->60%). Charging current was 1.25A.
A chinese device showed that Anker got about 3200ma*h from power supply. And it delivered about 2200 ma*h to Nexus 9, which really looks like 33% of its 6700mah battery.

andray said:
Bought one yesterday, did 2 full charge-uncharge cycles:
1) Razr Maxx XT910 +35% (65->91%) and Nexus 9 +12% (27->40%)
2) Nexus 9 +33% (27->60%). Charging current was 1.25A.
A chinese device showed that Anker got about 3200ma*h from power supply. And it delivered about 2200 ma*h to Nexus 9, which really looks like 33% of its 6700mah battery.
Click to expand...
Click to collapse
I'm not sure what you got, but the review was for 3350 mAh lipstick battery from Anker, this model on Amazon. Not 6700mAh battery. Wonder if you got something fake?

vectron said:
I'm not sure what you got, but the review was for 3350 mAh lipstick battery from Anker, this model on Amazon. Not 6700mAh battery. Wonder if you got something fake?
Click to expand...
Click to collapse
no, no! I mean that powercore+ mini managed to give additional +33% to Nexus 9's 6700mah battery.

andray said:
Bought one yesterday, did 2 full charge-uncharge cycles:
1) Razr Maxx XT910 +35% (65->91%) and Nexus 9 +12% (27->40%)
2) Nexus 9 +33% (27->60%). Charging current was 1.25A.
A chinese device showed that Anker got about 3200ma*h from power supply. And it delivered about 2200 ma*h to Nexus 9, which really looks like 33% of its 6700mah battery.
Click to expand...
Click to collapse
I have tested 3 of these.....
multiple charge/discharge cycles gave similar results....
My usb monitor shows. for full discharge (100-0)%....
Capacity: 1.657Ah ( @5v ) , 8.622Wh := 2.23Ah (@3.7v) ...or 2230mah
This is almost identical to what you got.
Charging(from usb power -->> anker mini ) : 15.858Wh = 3170mah .....from (0-100)%
also similar to what you got..... confirmation of your results ( and mine).
Yes, it's only useful as a partial boost......
(Note5 : 5% to 83% ... real world test)
......for todays high-end smartphones