BAK released the new N21700CD 5300mah battery

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vapcell Dennis
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BAK released the new N21700CD 5300mah battery

The actual capacity is about 5400mah, and the power is slightly weaker than that of Samsung 50g and BAK CG

http://www.bakpower.com/yybk_rlx_en.php

Edited by: vapcell Dennis on 08/07/2022 - 09:52
Pajda cz
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Do you have few samples in stock? I would add this cell to the ongoing cycle life tests for community.

raccoon city
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Excellent news!  :BEER:

vapcell Dennis
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Pajda cz wrote:
Do you have few samples in stock? I would add this cell to the ongoing cycle life tests for community.

we have only 300pcs,The factory hasn’t mass produced yet

Pajda cz
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The BAK N21700CD will be added to my cycle life tests soon thanks to the vapcell Dennis support. Thumbs Up And more to come! Wink

BlueSwordM
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@Padja cz, thank you a lot for the testing.

Anyway, I have to ask a question as I can’t seem to find any definite answer to this:

Is is true that even the latest Samsung 30Q revisions have unaceptably high self discharge?

My very own high current Beryllium Copper springs Gen 3:
http://budgetlightforum.com/node/67401
Liitokala Aliexpress Stores Battery Fraud: http://budgetlightforum.com/node/60547

Pajda cz
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BlueSwordM wrote:

Anyway, I have to ask a question as I can’t seem to find any definite answer to this:

Is is true that even the latest Samsung 30Q revisions have unaceptably high self discharge?

I don’t have a definitive answer either. My tests only show the behavior of the cells under laboratory conditions, which can be interpreted as “showing what can be expected from the modern cell technology if everything goes well…” where everyone who has ever played with batteries has sooner or later come to the realization that this is not always the case.

So you probably have seen my other synthetic test https://endless-sphere.com/forums/viewtopic.php?f=14&t=117028 where the Samsung 30Q6 passed without problems, the older 30Q146 pass it with similar results as well.

BlueSwordM
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Yeah, I saw your post, which is why I wanted to ask Big Smile

Thank you.

My very own high current Beryllium Copper springs Gen 3:
http://budgetlightforum.com/node/67401
Liitokala Aliexpress Stores Battery Fraud: http://budgetlightforum.com/node/60547

Oli
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Pajda wrote:

So you probably have seen my other synthetic test https://endless-sphere.com/forums/viewtopic.php?f=14&t=117028 where the Samsung 30Q6 passed without problems, the older 30Q146 pass it with similar results as well.

You must be measuring voltage before you put them in the drawer and when you first take them out. Is there some reason that you don’t add this information to the data.

You can't compare the big flashlight in the sky to the little flashlight in your hand.

Pajda cz
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Oli wrote:
You must be measuring voltage before you put them in the drawer and when you first take them out. Is there some reason that you don’t add this information to the data.

Because I didn’t find this parameter that interesting? Blushing (I find energy/capacity information more valuable) But this is a good question, I have the OCV data for “1 year” of storage and can add it to the table. Academic question is how set the conditions for proper reading OCV value of a “New” cell. I am adding 10 min rest time between each steps, but in this case it is not sufficient time for full relaxation.

Hoop
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I can’t make much sense of what is being presented in the “Calendar ageing tests of mixed cylindrical cells” thread. I’m not sure which line of data is related to a permanent, non-recoverable loss. What I’d find useful is knowing the resting voltage after a period of storage, meaning the self discharge over a period of time, and then the capacity after recharge, meaning the permanent loss due to storage time. Seems like it might require a few charge/discharge cycles to determine if the permanent loss is really permanent.

Oli
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I think a 10 minute period after a load or a charge is removed will get really close to a final resting voltage. Most of the bounce is going to be done in the first 1 minute. Rough guess 95%. Close enough for government work.

You can't compare the big flashlight in the sky to the little flashlight in your hand.