Review: USB battery box 4x18650 Coolook PB-2000

Could be a bad cell…a bad cell in the “battery” (multiple cells) can draw all of them down

Would you be able to see if this battery box will accept charging voltage other then 5v? Im looking to have it attach directly to a 10w solar pannel and not go through the solar pannel usb controller for better efficiancy

Sorry, but no.

The box has two inductors, this probably means that the charge controller is using a switching regulator, i.e. it might work with higher input voltage.

Seems like a good power bank but I’d like to add one thing.

As HKJ stated there are no directions at all included including no indication on how to open the darn thing without breaking it. Slide the lower cover straight back (away from the USB outlets) until it stops, about 8mm then lift.

Hopefully this will help.

I had the same trouble with the sliding cover on the Coolook, but once I figured out the direction to push it got easier.
Also, buffing the edges of the sliding parts a bit with coarse cloth seened to take off some rough edges, plus adding a bit of grease (well … nose oil, actually, nature’s lubricant …)

Loogies work wonders also. :Sp

> 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….
> Why is the Coolook draining them when it is turned off and not being used.

How are you testing that? I have a couple of the Coolooks, loaded with eight Samsung ICR18650 26C cells (salvage from a Mac battery pack that had quit working)

(the 10th cell in that pack failed to take a charge, when I tested each of the cells original; so I’ve got one spare that seemed as good as the other eight).
So I put four in each Coolook and one to spare.

So they’d been sitting for a few weeks in the two Coolooks
and using a USB Doctor plug, just today, one of the Coolooks showed 5.2v and the other 3.6v.

So I’m suspecting I’ve got one or more bad cells
— I’m charging all eight cells tonight in my Intellicharger I4, then will see if I can determine any difference among them with a Liitokala charger.
Then back in the box for a few weeks and recheck.

Something funny, anyhow.

For HKJ, if you have advice on how to test individual cells, or a pointer to such, I’d be glad to be educated about doing that the best way.

Any thought about replacing the springs on the Coolook?

I — uh — had all the cells out of one, and put the first two cells back in with one reversed — WRONG
Yanked the cells out again right away.

Barely in time.

Both springs had collapsed and changed color from overheating (and the springs were HOT)

I stretched them out again but they’ve lost some temper.

It doesn’t appear my screwup affected the electronics, I just — “just” — created a short circuit briefly.
Not enough to drop the measured voltage on the cells. Or catch the house on fire or poison myself or anything.

So I’m mentioning this as a caution — flat top cells salvaged from computer packs without the little bump on the positive end need to be looked at carefully twice.

I’m not sure if I need to replace those springs I overheated; if so I wonder if something other than stock chrome plated steel springs would be a good idea in this use.

Use the LiitoKala in analysis mode.

The mR readout measures the internal resistance, that is an indication of how worn down the battery is: A low value is best.

I notice on your review page you added

Can you say what to check for, or how long it would take to show up as a problem if charged cells are left in the box that has the high standby current?

I have two of them bought at different times.

That was from users, I have not tested one.

If you can do this type of setup:

You can check the current. Below 1mA is fine, above 10mA is bad (A full load of 3400mAh cells is 13600mAh or 56 days at 10mA).

That doesn’t show where the Coolook is connected,
guessing — so that’s
— take the Coolook as a USB power supply
— plug a USB-powered charger into the Coolook
— measure between plus and minus terminals for one of the battery slots on the charger?

No, you have to do the current measurement inside the Coolook, with only one battery in it.

Oh, put the Coolook in where you show the Trustfire — one battery in place, piece of insulator (white stuff) to allow inserting the meter in series with the battery. That should have been obvious to me. Thank you.

A late caution on the iPower Coolook battery box

I got a couple of the white ones, and after a few years the outside surface has gotten tacky and collected a lot of dirt and dust.
I suspect too much or the wrong kind of plasticizer used in the material of the case.

Has anyone who got the black model noticed this sort of issue?

I’m wondering how to clean the sticky stuff off. Maybe the “Goo Gone” solvent, I’ll try that first.
No luck with hot soapy water nor rubbing alcohol.

You need to know the input voltage for your device that you will charge autonomously. USB specifications correspond to 5V DC (5 Volts DC). The current consumption may differ (1A or 2A). You can connect a smartphone or other gadget that needs a current of 1A to the 2 A connector without any problems. The device will not take more than you need. The entrance of the power bank itself is very often polluted and deteriorated due to improper handling of it. Because of this, the device may break, and FLASH DRIVE RECOVERY will be required. So you need to use it carefully.

Late followup – I bought two of the Ipower Coolook battery cases mentioned above to keep in my earthquake cache. After a few years both have become sticky, covered with accumulated dust and fuzz, unpleasant to touch. I assume it’s a volatile plasticizer, the same thing responsible for "new caar smell’ — dagnabbit, it’s just icky.

So I’m pulling the batteries and wiping them down with “Goof Off” ick remover.

Ick.

Once they dry rot its over. The plastic is breaking down.

It was probably cheap garbage to begin with. Not worth the time OP spent to write the review.

Oh well easy come easy go.

Once they dry rot its over. The plastic is breaking down.

I’m afraid so. The plastic is justs scabby, peeling and ugly. Too cheap from China again.

Regrettably, the box is just peeling and flaking and accumulating sticky dust all over the outer surface.