Recommended Cell Supplier from China?

Usually works with Efest which are great but this "new" stock they received of 25R is 2 year old (at least they are honest) and they have nothing else while this is my main cell.

Worked with a few different suppliers and unfortunately only Efest provided clean looking cells that are a high Group rank inside the Grade A category.
For those of you who don't know, the groups go from A to F (A being the best) and most usually sell the lower grades within the A grades which range from minor physical defects (that most will not even spot) to heavy dents in the cells (yes, still ranked within the grade A).

So, any recommendations?

Try QueenBattery or Vapcell.

And small remark to battery quality grades. You are right that it is important to get cells clean without scratches or dents. But crucial is also the consistency of cell internal parameters, particularly (DC)IR and capacity. This is unfortunately much harder to evaluate.

Pajda said:

Try QueenBattery or Vapcell.

And small remark to battery quality grades. You are right that it is important to get cells clean without scratches or dents. But crucial is also the consistency of cell internal parameters, particularly (DC)IR and capacity. This is unfortunately much harder to evaluate.

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Even when I ran into heavily dented cells (of course didn't use them), the IR was within spec and consistent.

I just googled Queen Battery and it seems that they are not a supplier on Alibaba but in AliExpress which is where the all the junk grades and old stocks are dumbed in so I wouldn't trust them.

rg12 said:

Even when I ran into heavily dented cells (of course didn't use them), the IR was within spec and consistent.

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Good for you

rg12 said:

I just googled Queen Battery and it seems that they are not a supplier on Alibaba but in AliExpress which is where the all the junk grades and old stocks are dumbed in so I wouldn't trust them.

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I did not have any problem with the QueenBattery orders in the past, I think that Alixx is only one of their advertising channels, you can contact them and order directly at: wangxin570@gmail.com. Today for EU orders is one of the best distributors Nkon.nl and If you calculating with the issues with the shipping from china at this times, the QB offer is not as interesting.

Pajda said:

rg12 said:

Even when I ran into heavily dented cells (of course didn't use them), the IR was within spec and consistent.

Click to expand...

Good for you

rg12 said:

I just googled Queen Battery and it seems that they are not a supplier on Alibaba but in AliExpress which is where the all the junk grades and old stocks are dumbed in so I wouldn't trust them.

Click to expand...

I did not have any problem with the QueenBattery orders in the past, I think that Alixx is only one of their advertising channels, you can contact them and order directly at: wangxin570@gmail.com. Today for EU orders is one of the best distributors Nkon.nl and If you calculating with the issues with the shipping from china at this times, the QB offer is not as interesting.

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Will ask QB if they can provide photos of the actual cartons.
Thanks

Pajda said:

rg12 said:

Even when I ran into heavily dented cells (of course didn't use them), the IR was within spec and consistent.

Click to expand...

Good for you

rg12 said:

I just googled Queen Battery and it seems that they are not a supplier on Alibaba but in AliExpress which is where the all the junk grades and old stocks are dumbed in so I wouldn't trust them.

Click to expand...

I did not have any problem with the QueenBattery orders in the past, I think that Alixx is only one of their advertising channels, you can contact them and order directly at: wangxin570@gmail.com. Today for EU orders is one of the best distributors Nkon.nl and If you calculating with the issues with the shipping from china at this times, the QB offer is not as interesting.

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Just received a reply from Queen Battery, what a scam...

I asked for a photo of the cartons, so they provided a photo with the batch codes censored.
I asked why is that censored and he didn't reply about that.

Also asked for grade A only and the carton said Rank B Group B meaning B grade and second group from the top within the B grade.
So I reminded the dude that I asked for Grade A only and he said that it IS grade A and that I should not ask him about grades and that I can go order straight from Hong Kong.

No wonder they trade only on AliExpress.
Junk.

Thanks for informations. This manner definitelly does not look good. :?

Pajda said:

Thanks for informations. This manner definitelly does not look good. :?

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What is also disconcerting is that IMR (Houston, TX) no longer carries LG Chem. Closed out all of their existing LG inventory several months ago. Possibly something to do with the Trump's trade war with China.

NKON has new terminology ("floating") for Grade B cells ... https://eu.nkon.nl/rechargeable/li-ion/18650-size/lg-inr18650m36-3600mah-10a-floaten.html ... and they add "Use A Good Bms In Any Case." How does one distinquish a Grade B BMS from an Grade A BMS :wink:

Also, the following WARNING was recently added to the wrap on IMR's inventory of 30Q 141 cells ... https://www.imrbatteries.com/samsung-30q-18650-3000mah-15a-battery/ ...

WARNING: FIRE HAZARD
NEVER CARRY IN POCKET
NOT FOR E-CIG OR VAPE

eMark said:

Pajda said:

Thanks for informations. This manner definitelly does not look good. :?

Click to expand...

What is also disconcerting is that IMR (Houston, TX) no longer carries LG Chem. Closed out all of their existing LG inventory several months ago. Possibly something to do with the Trump's trade war with China.

NKON has new terminology ("floating") for Grade B cells ... https://eu.nkon.nl/rechargeable/li-ion/18650-size/lg-inr18650m36-3600mah-10a-floaten.html ... and they add "Use A Good Bms In Any Case." How does one distinquish a Grade B BMS from an Grade A BMS :wink:

Also, the following WARNING was recently added to the wrap on IMR's inventory of 30Q 141 cells ... https://www.imrbatteries.com/samsung-30q-18650-3000mah-15a-battery/ ...

WARNING: FIRE HAZARD
NEVER CARRY IN POCKET
NOT FOR E-CIG OR VAPE

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I've heard that NKON and other European suppliers are no better than China if not worse.

A good BMS means one with fast balance like an active BMS but I would never use B grades as it is for dumb people who save money in the wrong places.
Maybe it's a good thing, all the dumb people will go up in flames :lol: :lol: :lol: kind of a "green" natural selection :lol: :lol: :lol:
Why not buy cheap B grade brakes for your car? just slow down earlier in case they don't stop you know :lol:

About the e-cig warning, it doesn't have anything to do with grades, it goes also for the new 25R's

rg12 said:

A good BMS means one with fast balance like an active BMS

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My post about BMS (A/B) was as much tongue-in-cheek as fact. You bring up something that seems to be a mystery to many of us. How does one know if a BMS has fast balance or slow balance? Would you explain what you mean by "active BMS" as it relates to fast balance versus a BMS with slow balance?

Is it possible that those DIYers reporting a problem with their 3OQ 136 battery pack having a high self-discharge issue was in fact not a QC cell issue, but rather an "active BMS" that was tooooo active not knowing when to stop :wink: (even with pack resting).

you can't carry it in your pocket because I always carry my 24-inch gold chain in my pocket I can just imagine if that gold chain touch North and South.
Also my keys are 24 karat plated highly conductive we're not a good practice.

Every BMS has settings for balancing

most important is the Balance Current rate, and whether or not that varies with the voltage delta

"Active" balancing (should) mean that the rate is constant regardless of the delta

then you have the Starting Voltage

and the Ending Delta.

IMO all should be user-custom adjustable.

If you cannot find out before purchasing, IMO do not buy it.

Or just buy a dedicated Balancer and either disable the BMS from balancing

Or, buy a protective-only BMS.

The idea of shunting current from the high-voltage cell/group to the lower one(s) rather than burning excess off via resistance

is another use of the term "active"

but IMO does not matter so much as the actual amps rate at which the job gets done.

Yes there is an infinitely of ways these devices can fail, so when testing cells they should be easily removable.