Review: USB battery box 4x18650 Coolook PB-2000

Check that plug charger is dangerous.

http://www.lygte-info.dk/info/usbPowerSupplyTest%20UK.html
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Thanks for pointing that out to me, but it looks like it is the 240 volt version, whereas I got the USA version with the 2 flat blades and I don’t see that model in the review, with that said though I haven’t even used the usb plug-in charger it came with, rather I used the Samsung charger that came with my phone. The battery power box itself seems very well built and arrived 3/4 charged already, took no time with the Samsung usb charger to top it off.

Again thanks for the heads up, to be safe I’ll probably not use the included usb charger even though it’s a different model than reviewed.

So the specifications saying “Charging input: DC 5V, 0.5A~2.5A.” is wrong? And you can’t use a normal USB charger but need a custom DC power supply?

Why? It’s surely fake and not the adapter tested in the charger tests mentioned earlier?

One detail I do not check, is how the charge circuit handles lower input voltage. If it reduces the charge current, it will probably work with most chargers.

You can get USB chargers that are powerful enough to handle this box at full charge current or you can take the batteries out and charge them in a normal LiIon charger.

Can you recommend any 2.5/3A USB chargers that are USB charger coded and not that dodgy?

Probably not.

USB charger is only rated up to about 1.5A. This does not prevent it from delivering more current, but manufacturers may chose to label it as Apple 2A.

USB chargers with multiple outputs are usual the best, they often run all the outputs in parallel, i.e. a charger with 4 0.5A output, will have a total of 2A, that can be drawn from any port, as long as the other ports are unused..

Yes, I ment multi-output chargers. There are some rated for 3A/15W or so but probably of questionable quality (and says for iPad etc)… I know there is a model from Pisen with 2A+1A “for Samsung” but only for Chinese market and I haven’t seen it for sale anywhere.

I could always use one of the 5V 4A power supplies I have, but they are not so small and can’t be used for anything else. If I bring an 18650-box on travels I want to be able to use the same USB chargers as for me and my gf’s phones and tablets (1A-2A, no Apple products).

mfm, was it this Pisen charger, with separate 1A and 2A USB sockets?

Yes. However, I’m only marginally interested and I won’t buy any more Pisen products until they replace my broken power bank.

(Also I imagine it would be a headache to order from tmall.com, even though the Chinese language and delivery to a Chinese address would not be a problem in itself).

My Coolook battery box only gives 1A out of either port. I bought it to charge my ipad, but it’s of no use to me.
It will show charging, but my ipad just holds its own and after a while shows not charging.
I tested both ports with a charge doctor, and they read 1A. I also tested my ipad charger with the same charge doctor and it reads 2.1A

I’m still looking for a good battery box that will give me 2A for my ipad.

This 2 x 18650 box can do 2 amps. Ebay $8.29. Also the 4x18650 Huamen/Evertones ET-406. Neither are ideal for charging the 18650s. With luck there might be room to cram a tp4065 charger board in the 2 x 18650 box under its pcb.

it’s not that your Coollook can’t put out 2.1A on one of the ports…its the device charging needs to see the apple charge signature from the charging device…if it doesn’t see it, it will automatically restrict it’s maximum charging capability…

You need to setup a charge controller or build a dedicated charging port for your device

http://oshpark.com/shared_projects/NIDe7kjj

The chip mounted on this lets the device plugged into it know it can deliver the proper current

Actually to fix your problem…you need a USB wrapper…a device to get between your charging device and charger and then tell it thru resistor bridges and whatnot what juice to pull

hmmm…wonder how accurate that is

Alot of times I see these chargers say they have that coding but looking thru a charge doctor it just won’t pull more than 1A, then opening it up see the pads for the resistors connected to the center data pins and nothing being there…save that .0001 cents by not putting those resistors in

The one I tested used that coding.

The new verson 7 miller ML-102 might be able to do 2.1A.

I managed to buy some PB-2000 off the bay, togheter with the newer Aili Power box. The PB-2000 have a superior electronics, but I like the Aili for their look.
The PB-2000 is the best power bank I have seen around; it doesn’t use electrolytic capacitors, and have an output LC noise filter only seen in high-end power supply design. Also, the efficiency is the highest in this class of equipment.
While conducting some current measurement, I did a mistake. I connectected the multimeter, set on the 10 Amp range, in parallelel with the batteries. I have a multimeter with a fuse on the 10 Amp range, and initially I tought that the multimeter fuse was the only one casualty conseguent to my mistake. The batteries, even if unprotected, had their own PTC device, they were undamaged. But.
I tried to power on the PB-2000, but the green LEDs behaved erratically. Connected a light bulb, but it lighted dimly; measured the output, it was 3.2 Volt. All in all, the circuit was not stepping up the battery voltage anymore. After some trouble shooting, I found the switcher MOSFET (the only visible big transistor) had the gate shorted with the source, and the driver chip (a tiny six pin SMD component on the other side of the PCB) had the output open. After a tracking analisys, I realised that, by shorting the batteries a capacitor had discharged, via the ESD protection diode in the MOSFET, thru the driver; destroying the driver IC itself and the power transistor. So, my advice, do not SHORT the input!
Aside this fault of mine, the PB-2000 remains the best DIY power bank available at the moment, and I would like to thank HKJ for the insightful review.
Anthony

Mine doesn’t seem to be coded for apple as it won’t give more than 1A to my ipad.
OK, too bad, but the thing that gets me is that if I charge it up full and leave it for a week or two, the cells seem to self discharge down to the cut off. These are brand new Panasonic 3400 cells, and there is nothing wrong with them. Why is the Coolook draining them when it is turned off and not being used.

For what it is worth, I’ve noticed that knock-off lightning cables don’t get things right for delivering full current to apple devices with powerbanks that work fine with genuine cables.

Question going back to the original review at the top:

It says: “When using multiple batteries, remember that they must have the same voltage when put into the box, easiest way to do this is to charge all batteries first.”

No problem with that, I can charge the batteries in an Intellicharger I4 independently.

But — after they’ve been run down a bit — trust that the batteries now are at the same voltage when partly discharged, and use the charging port?

Has anyone checked voltage on cells after the batterybank has been used, to see if they come down at the same voltage?

Look at this photo:

The two metal rails connects the batteries in parallel, it is simply not possible for the batteries to have different voltage.