Best High Capacity 21700

Dunno why everyone is wasting their time - look at Enderman's post - the best 21700 cell is the Vapcell T50 which is a Samsung 50S.

Not say'n they are easy to get, but the title of this thread has only one answer.

Part of the reason I created this post is because those are nowhere to be found and was looking for a substitute. The T50 were a limited run for Vapcell and currently they’re about impossible to get. Samsung 50S are also nowhere to be found. The 50G is almost as good and can still be found (at least for now).

I wonder how the Tesla’s stack up charged to 4.1V. I’d bet they don’t charge beyond that in the cars…

EDIT: Just checked the mail. They arrived. I’ll do some tests to see how balanced they are.

You may want to consider Orbtronic. From what I hear they are “A” grade.

Mooch tested them, they’re better than the 50E but worse than the 50G and 50S.
If they were brand new then maybe they would be able to compete with the 50G, but not likely to beat the 50S.

The 50G is probably the best one available now. Runners up are the 50E2/3 (but not really available) and the Tesla Sanyo NCR21700A. The rest are not as good for over 10 amps. Either wait until the 50S is available (wishful thinking) or Vapcell gets some and charges $16 per cell.

Liionwholesale has a house 21700 that are E2s

Man, Liionwholesale is sold out of almost everything.

Where is the demand from ? It cant be from vapers and flashaholics.

Ebike community

Manufacturing slowdown from the pandemic, supply and demand.

50G's can't compare. I bought a pair of the T50's twice from their Ali store, just wish I bought more.

As does everyone :weary:

Technology improves with time, soon enough 50S performance will become standard and we’ll desire a 53S or whatever.

I just got some new Samsung 50Es from Battery Junction.. They are now a tan color vs blue. And they don’t charge in my Opus BT-C3100 unless I put a magnet on the positive contact. I don’t doubt they are legit batteries, but I don’t like they changed color and the positive contact is too recessed to be charged normally.

Received my order of Tesla 21700s from Tech Direct Club earlier this week. I am NOT set up to conduct any kind of serious battery testing, so bear that in mind with what I am about to share.

Most noteworthy, I ordered a pack of 3 and yet received 5 cells, so that is a pleasant surprise (or possibly an error on their part?) Visually I see nothing noteworthy about the cells. The positive terminals are not recessed as I have sometimes heard these Tesla 21700s are. They definitely seem like they could be re-wrapped Samsungs; I don’t have a 50G to compare, but the positive terminal and under-wrap look just like my 50Es.

In terms of capacity, now we get to the disappointment. I only have an Xtar VC4S charger to use for testing, but the first cell I have tested with the “grade” function came out to 4313mah, well below the minimum rated capacity for say a 50E. These are obviously salvaged cells, so keep that in mind; at least from this sample size of 1, you are getting a cell that has been through quite a few charge cycles and taken the commensurate capacity loss.

Internal resistance measured higher than my 50Es as well although my charger was giving inconsistent readings. I am currently “grading” a few more and will report back my results.

So all in all these are cheap cells I’d use for my 2nd-tier lights, capacity and discharge seem to be much lower than rated (perhaps unsurprising given they’re salvage)

I bought a pack of three from them, and got ’em on Monday.

It’s odd that you received five of them… I ordered a pack of three, and received three.

From what I understand, the button top on these are added by a third party, and are recessed a bit from the factory. Battery pack

All I have to test with is a Vapcell S4 plus, and according to that, one of my 50G’s came to 4929mAh at 1A.

I’ll charge up my Model 3 cells, and see how they do.

It will be interesting to see what you get for results. Yes, the top is added since from the factory the cells have a special cap for Teslas battery pack. The Sanyo ncr21700A is a 4800 mah nominal cell for 10A CDR. I think the internal resistance is between 20-30 miliohms. It will be interesting to see how many mah’s escaped and how much the internal resistance has changed.

You better pick one before they are all gone. It’s slim pickings on most reputable sites.

I just received 3 from Tech Direct and they were packaged the worse I’ve ever seen. They were thrown together into some bubble wrap and then into a generic gray plastic envelop. However the bubble wrap container wasn’t taped to seal the batteries inside of it and they arrived flopping around in the gray plastic with the bubble wrap off the the side. So basically a few mil of plastic protecting the batteries from the bumps they got being shipped to me :person_facepalming:

Also no tape over the contacts or anything to keep the batteries separate from each other. And I thought there were regulations on how lithium batteries were supposed to be shipped!

Oh well at least there aren’t any dings or divots on them.

Getting back to the batteries themselves…they all read at 3.68v with IR’s of 80, 71, and 74. However this is off of my Opus 3100 and to be honest I don’t think it’s very accurate so take those with a large grain of salt.

I’m in the process of charging them and will have discharge readings probably tomorrow.

That’s dangerous. The batteries ideally need to be in a protective case like every other seller I’ve bought from.