4x18650 battery box question

Hey I have a similar ordered last week from suntekstore but there is also a USB in for charging.
I am not sure why I need this but someday I would like to charge some batterie with a solar panel to transfer the daylight in the night or so.
Please describe your experience with this.

Yup! It’s there. It says TP 4056 1220, which is a little different then the one you posted a pic of. My eyes are starting to go.

1220 is most likely a build date code.

I wonder if I could just use a usb to usb cord, plug it into my iphone wall jack and charge it that way. From poking around on here Ive kind of learned that 18650’s can potentially be dangerous, and I dont want to charge it and come home to my town house burned to the ground. Mostly because of all the cool stuff I have, not because of the house itself. My goal is to be able to charge my iphone for as long as possible and doing it cheaply and safely. 4 of the unprotected batteries were $13, the charger was 5.50 and the box was 8.44, so if this works I should have a 10000mah battery pack for $27

$3 batteries vs. being safer. Choose 1.

EDIT: This doesn’t say what you have is unsafe. It says there are probably safer options to address the concern you raised about safety. Can’t know what you have under those wrappers . . . but personally I’m more comfortable with known oem cells, or even those from a good laptop pack.

Why do you think they are unsafe?

Which batteries did you buy?

http://dx.com/p/trustfire-18650-3-7v-2500mah-rechargeable-lithium-batteries-2-pack-19770

I have a 4x18650 box bought with some panels from Cottonpickers at CPF Marketplace. There seem to be quite a few of these on ebay in various forms.

If your box has USB in (mini USB socket) then you can charge from any USB source including Solar. FYI, I have some of these panels from Intl-Outdoors and I can confirm that they put out the claimed 400mA each.

http://www.intl-outdoor.com/5v-400ma-monocrystalline-solar-panel-p-462.html

There is no blocking diode on these so you might like to check that your box doesn't discharge back through the panel if you leave it connected in low light.

I connected 2 of these panels in parallel for 800mA (in strong sunshine) but even at this rate it will take a long time to fully charge 4 drained good quality cells. Remember also, that solar panels drop off dramatically in efficiency when not angled directly to the sun; for best results you will have to keep re-aligning the panels periodically.

Keep in mind also that high states of charge + high heat is one of the big killers of Li-Ion cells. If you are charging via solar, try to find a way to keep the 18650 box out of the sun and as cool as possible.

Other than solar, your USB in for charging means you can use any USB source such as an AC supply, car adapter or PC to charge up the box. Many PCs continue to supply power to the USB ports even when switched off, so plugging in here is a convenient way to charge.

The circuitry in mine seems to cut the charge pretty reliably at 4.19V but yours may be different. Because of the strange warnings NOT to use PROTECTED cells in some of these boxes, you would be best to make sure you use only good quality cells such as Panasonics or Sanyos.

Hope this info helps.

I installed the batteries in the portable battery charger, hit the activation button, put the case back on and now its charging my iphone. The charger for the charger still hasnt come yet.

Mine came today
http://www.suntekstore.com/goods-14002339-5v_mobile_power_supply_usb_battery_charger_18650_box.html

It’s different

Ics are grinded down so no chance of finding out what circuit
Also there is a button and three LEDs on the side which show you the battery status a red a green and a blue one.
Just for getting sure I put a protected cell in there for test.

Batteries are parallel so no chance the will get balanced, but just for playing around it should be ok. I would not put unprotected cells in it when I would only charge it through this device, if you have a cell which has lower capacity it will over discharge it. Not sure how CCCV will work with parallel cells?

I think the only difference is the lack of a miniusb. I installed the new unprotected batteries, hit the little button inside, closed it up, charged it using the wall wart I bought and took it off when the light went green. Seems to work great.

I got 6x 18650 box, and I must say, it’s remarkably more efficient than 4x 18650 one I had previously!

Here are discharge data:
directly: 14498mAh at 3.73V = 54.1 Wh
USB1: 9941 mAh at 4.90V = 48.7 Wh
USB2: 9598 mAh at 4.90V = 47.0 Wh
12V port: 3778 mAh at 12.3V = 46.5 Wh

Therefore, efficiency is:
USB1 (marked 2A): 90%
USB2 (marked 1A): 87%
12V: 86%

With the 4x 18650 box, I had efficiency of just 81% (out of the only USB output)!

So i charged it up with my mobile phone charger, LED gets green battery 4.19V. Good.
Also tried the other input with a normal Dc round plug3.4mm works also(inner pin is plus and outside should be minus).
Tried no voltage over 6V in.

I put it on my power supply and played a bit, under 3V it switches off…under voltage protection is built in. good
Pulls about 1.3A almost over the whole voltage range 4.2-3V from the battery, with a iPad plugged in.
I shortened one spring to put a protected Sanyo in, would go without but I wanted a perfect fit.

Will you link us to the 6x box you purchased? Now I have to have one.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150946900822
It’s not available anymore, but you might find same one by other eBay or AliExpress sellers.

What happens if you put a protected cell in a charger that already has protection? The ebay page specifically says to use unprotected batteries. I measured the batteries after they were charged and it read 4.28v on my harbor freight multimeter, so the overcharge circuit must have worked.

What can happen? Nothing.
I am on the save side of life and my batteries are save too, when I use protected ones. Without there can happen anything.

I could charge a unprotected cell in mine to check if the charger has proper voltage switch off or if it was the protection of the battery.

should the charger be cutting off before 4.28v? is that overcharging the batteries?

Yes it should.
My 6 cell one stops charging at 4.2V, and in few hours, voltage drops to 4.17-4.19V, so it might have better charging circuit than 4x one.