Difference between cheap Green and Black 18650s? (Update: Wallbuys says the Greens have Seiko circuits)

So I have 3 sets of batteries in the mail from wallbuys.

2 pairs of cheaper green ones:

1 pair of Keeppower:

Now is it actually worth paying extra for the black ones like keeppower / AW/ orbtronic ect or are the green ones the same thing ?

PS: I ordered the green ones for my SRK before I knew that the keeppowers only cost a few bucks more.

UPDATE: Just an update. I had a chat with Wallbuys and they confirmed that the green 3400mah ones use Seiko protection circuits !

Keeppower and the other better brands use seiko protection chips (seiko is highly regarded). Definitely worth it imho. $9.60 is a good price for 3400mAh keeppower. Any higher and you can get 3400mAh with seiko elsewhere.

What do the green ones use ?

seiko make a protection chip for battery?never know that especially seiko is a famous watch maker :bigsmile:

I do a little test with the green ones right now, they arrived today.
For the use with 2.8A drivers, they seem to do fine.

I run a 2,8a XM-L drop in on high and the cell seems to hold the output fine.
(I got problems in the past with not so good cells, they couldn’t deliver the 2,8A when the voltage drops.)

My cell is at 3,9V right now and still going strong.

It a mystery. :smiley: :smiley:

Bit of a joke because I call those mystery protection. Added by an unknown company or several, they never add a label or small sticker to identify who made it.

Some use a chip marked DW01. Made by a Taiwanese company, fortune semiconductor.

I see. Damn I shouldn’t have ordered them lol.

So the keeppower is the best value at the moment for panny 3400s with the good circuits ?

You could also try the Unprotected Panasonic 3400 cells. :slight_smile:

After 35min. on high, I shut it down for a few minutes to test the voltage, the cell is down to 3.76V (starting voltage @ 4,18V).
I installed the battery again after I let the flashlight cool down for a few minutes and switched the light back on and the driver keeps jumping to the low output, the cell can’t deliver the 2,8A anymore.

Would the Keeppower perform better?
I don’t know.

Are you measuring the voltage under load / while the light is on? I think it will be less then 3.76v under load. Likely less then 3.3v.

To drive an XM-L at 2.8A you need ~3.3 volts. After ~35 min a Panasonic NCR18650B 3400mAh should have dropped below 3.3v under load. And a bit of voltage is lost in the driver. The common drivers we use can’t get 3400mAh out of the panasonic. Panasonic gets 3400mAh by going down to 2.5v.

A LG D1 would give more runtime at 3A but you need a 4.35v charger. Currently it seems the only easy 4.35v charger is from cottonpicker and its a bit costly. $50. Other 4.35v options are either DIY / not as easy or of questionable quality imo.

Hi helios, thanks for the heads up.

I was measuring the voltage after I turned of the flashlight, not under load.
I guess I learned something new tonight, I didn’t know that the voltage under load differs that much from the voltage of the cell resting.

According to the wonderful presented graphs of HKJ, the cell hits the 3.3V line after aprox. 35min., my noob conclusion is:
The cell behaved as expected, everything is fine.

EDIT: forget everthing I wrote from here, I set the comparator to 5A not to 3A

I checked the battery comparator again (as often in the last couple of days) and done a comparison of the enerpower 2900 3C version (contains a Panasonic NCR if I’m right) and the green protected panasonic, my (again noobish) conclusion is, that the high drain cell acts a bit better.
But I don’t know about how much runtime we’re talking about in reality, 2-3min. ?

Seems to be. If the price goes up on those keeppower, RMM’s protected 3400s would be a better deal for those in the usa at least.

I do not know if they are related, but Seiko Instruments does make a lot of electronic stuff.

Just an update. I had a chat with Wallbuys and they confirmed that the green 3400mah ones use Seiko protection circuits !

To be honest, I’ll believe it when I see it.
Its a selling point. Anyone who uses seiko would be sure to note it on the page.

If you have some on the way you can check them when you get them. $1.18 clear 18650 shrink wrap. You may be able to shift the pcb aside to read the chip without even desoldering the pcb from the battery.

Whatever protection it has just being a panasonic cell is already safer then something like ultrafire.