Got a 6 x 18650 power bank, with 1A and 2A output. But will not charge my tablet.

This is a new brand power bank I just got my hands on. I purchased it and the smaller pocket size version to replace our NewTrent brand power banks that were getting old. This Jackery Giant+ has been the only power bank that has been able to fully charge my iPad 1st Generation fully from a depleted 5% charge to full. What got me to purchase it was the fact it’s one of the only companies to boast using premium cells. It’s a keeper for me, and the small pocket version was able to charge our iPhone 6 plus from dead to 88%.

Jackery Giant

What I have noticed from building my own power banks and reviewing off-the-shelf ones that different companies send me is that there is no one charging specification that all the devices and power banks use to be compatible.

Some devices will only charge if they detect a “smart” charger and some devices will charge as long as they detect the right voltage/current. Some devices don’t seem to care one way or another. For devices which will not charge with a specific power bank, I have a “charging cable” which I believe is just a micro USB cable with the data pins shorted. About 8 times out of 10 this little cable will make everything start working. But day to day, I just carry the power banks that play well with whatever devices I’m carrying.

1 +
As Racer said many devices (tablets, phones) will not charge if you simply provide 5 volts at 2 Amps. The tablet checks the usb data pins, if it does not see the identification it wants, it will not charge.

The other possibility is that the usb identification does match what your tablet wants but the power bank is just junk. The tablet tries to take 5 volt at 2 Amps but the power banks can’t really provide it, the voltage drops and your tablet rejects the power bank as not suitable.

Richie086, the Jackery Giant sounds nice. The pocket version you have is the single 18650 one, correct? Have you by chance tried it with any android devices?

It’s hard to blame the device manufacturers for their devices being picky about charging. You’re charging a $600 tablet/phone/whatever with a $20 charger, and when your junk charger melts your expensive device, you’re going to send that device back to the manufacturer and expect a new one.

Halo,

There are some FAQ by folks on Amazon, from what I have read, it will charge an Android device. One such question is below:

*_Does this work with an android?

A: works with anything that has a USB connection for power ie like the iphone charging cable Damian MCCANN answered on June 17, 2015 _*

JACKERY MINI

Saying “it will charge an Android device” doesn’t account for the fact that there are thousands of Android devices out there and not all of them are compatible with chargers and power banks that claim to have a generic compatibility with Android devices. Deductive reasoning will help narrow it down if you try different devices with your power bank and different power banks with your device, in addition to testing different cables.

I fully agree with you.

my asus tf101 is very fussy.i wired a 12v cable up for it.
so dont feel bad that your 5v power bank wont charge it.seems to be a common wart with the whole series.mine wont charge from 5v.

Discovered this today also. I tried to charge with some GP power banks that I have got here in Norway (10400 and 12000 mAh) and it will not charge the pad either. I was sure I charged the pad when I was on two trip in India the last year, but I must have used my travel charger to the pad.

But good to know that is was not a bad power bank or bad batteries then. :smiley:

I wonder if the data pins have the correct charge signature on them

The small charge booster board I designed that shorts the D- and D+ pins together will allow an iPhone or iPad to charge from any 5vdc port (even a charging downstream port vs a dedicated charge port) because it tricks the device into thinking it is on a “charger” device rather than a computer…albeit at a 5W or 1A rate, but they will charge

This is my DCP enumerator board

A little info on the charge capability/power capability of USB

They have power banks with smart DCP now. Only kind I would get.
RAVPower 3000mAh Power Bank - 2nd Gen Luster Mini Scroll down and you’ll see the other models they have, most do well over 2 amps.
Anker also sells several models of smart DCP power banks

Cut the barrel connector of a 12V .5A wall wart and got my truck started. Gotta love dumb devices.

So then for the non-electronics-geniuses, what is a good DIY smart charger to put 6 good batteries in? The problem with these off the shelf chargers is that they are universally nowhere near their stated capacities from what I’ve seen.

I can highly recommend 4x18650 Coolook PB-2000.
I bought 2 from Fasttech. My android tablet and phones, my iPod, all Apple devices I tried charges great with this unit. My friends are using it when they come over and it newer fails to charge. It charges my picky Galaxy Tab 7.7 with same current as original Samsung charger. It can supply more that 2A without problems. By the way, I’m using some old laptop pulls in the power bank and I’m sure it’ll be even better with nice new batteries. Another thing I like is that battery voltages are nicely balanced when discharging. That’s not the case with some 3x18650 ENB power banks I’ve had. HKJ tested this power bank some times ago, here’s the review: Review: USB battery box 4x18650 Coolook PB-2000

Thanks for the recommendation, Noki. Looks like a nice charger. I have a Ruinovo I like, and it has 4 green Sony cells from a laptop pull. The 4 cells all tested about 2000 mAh but I could do way better with 4 Panasonic, and I like the Ruinovo too much to mess with it, though it can be a little picky about what it charges.

The Ruinovo is a nice, brushed aluminum but it’s killed a few devices by scratching glass/plastic with its sharp edges.

The smart DCP Anker and RAVPower power bank do not appear to lie about battery capacity.

LGABB41865 inside the previous 2600mAh model of the RAVPower power bank. LGABB41865 is indeed a 2600mAh cell.

I haven’t seen teardown pictures of the newer higher capacity models yet.

Now be aware that all power banks I have ever seen quote the battery capacity not the output after 5v boost losses. You should get 80-90% after losses. And then there are losses inside the charging circuit of your device as that 5v is dropped down to 3.0-4.2v (or up to 4.35v) during a full charging cycle. These losses are unavoidable and vary some depending on how efficient charging circuit in your device is.

A 3000mAh power bank will never equal a full 3000mAh charge of your device’s battery.

Here is two 6 cell power banks with smart DCP
Anker 16000mAh 2nd Gen Astro E5 $37
RAVPower 16000mAh 3rd Gen Deluxe $36
I’ve never seen a DIY (bring your own cells) power bank with smart DCP.

Is there anywhere else then Amazon you can get Anker power banks? Tried to order from Amazon Norwegian site, UK site and US site, and the two first site stated that they would send to Norway, but it stops and tells me that I can’t get the Anker PB to Norway.

Just to add my 2cent to the discussion, try also different usb cable…
Don’t ask me why but with chinese product (car charger, battery pack,…) not all the cable work correctly.
For example my car charger should not charge my android phone without an old micro-usb cable…

For phones etc, that could work. For my PDA, it has a another connection, so I have to use on of two cables I have to it. No one worked.