Anker PowerCore+ 20100 USB-C, Ultra-High Capacity Premium Portable Charger, 20100mAh External Battery, 6A Output Type-C Port for USB-C MacBooks, Nexus 6P/5X & PowerIQ for iPhone, iPad, Samsung & More

This purchase started as a sad story, but had a happy ending.When the power bank arrived, I pressed the single button and nothing happened. Hmmm. I read the instructions and found that a button press should display the remaining charge, so I figured it was merely discharged. I plugged it in to a Leviton in-the-wall-outlet charger whereupon the charge LEDs began to indicate the charging process had begun. The LED array is programmed to indicate the current state of charge before animating the charge indication. The LEDs showed the current charge was about 60%, so I became suspicious.I let it charge overnight, and in the morning the LEDs showed that it was working on the last 10% of the charge cycle. I watched it for a few hours and it never moved beyond the 90% mark. So I figured I try to charge my iPad with it. I plugged in the iPad's charging cable, and nothing happened. The iPad showed no charger input. I got the same result with my iPhone. No juice. So I plugged in a USB voltage/current tester, and it showed zero volts. So the unit was definitely defective. That is the sad part.I called the Anker tech support phone number printed in the instruction leaflet. The automated response system said there was a wait for tech support, but it allowed me to leave a callback number. So I did. Within about ten minutes, a very nice and articulate technician called me back. She asked me a few questions about how I had charged the unit and how I knew it was defective. She then checked my Amazon order (Anker must have fulfilled it, as they had a record of my purchase), and told me a replacement unit would be mailed to me free of charge. I asked if I needed to send back the defective unit and its accessories, but she said 'no' and that I should just recycle it properly.So in a couple of days, the replacement unit arrived and worked flawlessly! A very happy ending, indeed. Of course it came with a complete second set of cables, so I figured that offset the inconvenience of being without a power bank for a few days.I do not fault Anker at all for the failure. I am an electrical engineer by trade, and know that all electronic devices have nonzero infant mortality, and the perils of shipping can take their toll on even the most robust product. Stuff happens. The fact that they made me whole on the purchase speaks to their integrity, so much so that I immediately ordered the companion Anker charger and extra length cables for it, which all worked flawlessly.So now I had this defective power bank to play with, and of course I opened it up to see if I could find out why it failed. It took some doing to figure out how to open it (it is essentially a press fit into the case), but when I got it open, I found a very well designed and executed device. The battery array itself was a 2S3P array of LG brand lithium ion cells, model LGABF1L1865. The charge controller PCB at the connector end were proprietary, and looked very well done. A microscope inspection showed no obvious damage or manufacturing defects. I didn't bother to reverse engineer the circuit, since I already a had a working replacement, and life is short. So we will never know why this unit failed. I recycled the nice aluminum case and the PCB, but I did keep the batteries. A $2 battery protector from Banggood has turned them into a usable voltage source for some future project.So I have nothing but good things to say about Anker's products and especially their support. I expect to be a lifetime customer.

There aren't many batteries available that can power the new MacBook which is why I selected this. Added bonus of being able to use this for both my MacBook and my phone means I can give my other spare battery away to a friend. Works as described. Holds enough charge to charge my iPhone several times. 2 USB ports and plenty of power means I can charge friends phones also which happens often as my friends seem always to need a charge and never carry batteries and want to use mine. Before I needed to be stingy about allowing others to drain my battery, but this stores enough power that I don't need to worry about sharing.I really like that it's a backup power source for my MacBook. Works fine but be aware that the wall charger for your MacBook is 29W while this battery will send 15W. I also tested this via both using the Anker supplied USB to USB-C cable connecting to the battery via USB and the cable that came with my MacBook connecting to the battery via USB-C and all the ports for the battery seem to send out 15W. What that appears to mean from my testing is that it will charge your MacBook battery very slowly. Not sure if it depends upon what I was doing as at times it seemed to not charge but just keep my MacBook battery from decreasing while other times seemed to charge slowly. So I would recommend connecting the battery "before" you ran out of power on your MacBook. With the MacBook off I am sure it'd probably charge faster.Nice design, solid build. They make smaller USB-C batteries and also a larger one, but this size I felt balanced power and size / weight better for me. I travel a lot so this will be very useful so I cut the technical information part from the manual and taped to the back of the battery as shown in the picture as the printing that's on the battery end is so small and light that I have no idea what it says and I am sure the airport staff wouldn't be able to read it either. I am sure they will want to check the stats on this battery before allowing you to take it on a plane. I can just show them what I taped on the battery if they ask as it is indeed within the permitted limits.Others have given this good reviews and those complaining were complaining mostly about 2 things. (1) Some have said it doesn't charge the MacBook, but it does. You just need make sure to click the button on the battery "before" you plug it into your MacBook otherwise your MacBook will try to charge the battery instead. So this complain is invalid. (2) The cables that come with it aren't good. They seem ok to me, but I have no need for them anyway as I have my own quality cables I use so I'll throw these away. I did check them though and they seemed to work, but I did no "technical test" on them so I have no real ideal of their quality other than they "look" ok. I can charge the battery with the cable and adaptor for my MacBook and use my other cables to connect devices to the battery so I never use cables that companies send with products as they are typically crap.I'd highly recommend this to anyone especially those with the new MacBook. Please consider the size and weight before buying though as you might want a smaller or larger batter which Anker does make.