Test/review of LiitoKala 21700 4000mAh Lii-40A (Yellow)

LiitoKala 21700 4000mAh Lii-40A (Yellow)







Official specifications:

  • Model: Lii-40A

  • Size: 21700

  • Chemistry: IMR

  • Nominal Capacity: 4000mAh

  • Nominal Voltage: 3.6V

  • Discharge: 40A Max Continuous

  • Positive: Flat

  • Rechargeable: Yes

  • Dimensions: 21.2mm x 70.4mm

  • Weight: 61.2g



High current 21700 cells from LiitoKala and also with good capacity.










The two cell matches discharge curves fairly well and capacity is nearly constant at any load.



The cells get warm at high current.





I do not know exactly what happend with the B cell, but my battery holder was melted, i.e. the strange curve is probably due to a damaged battery holder and not the cell.















Conclusion

The cells has the rated capacity and capacity is fairly constant with load, but they do get rather hot at high current. This means they may handle high pulse current, but 20A or more in constant current is not a good idea.


Notes and links

How is the test done and how to read the charts
How is a protected LiIon battery constructed
More about button top and flat top batteries
Compare to 18650 and other batteries

Oh yeah, I waited for this test. Good battery in general and very good for the price.
Thanks HKJ!

Thank you for yet another review. It seems that my Samsung INR21700-48G is still best choice as long as I don’t exceed 10-12A.

Well, a Lishen cell with almost 4Ah and a 3C rating.

It's appeal lies in its demolition class price LoL.

Cheers ^:)

$7.05 / 2 pieces for the next 2 weeks:
https://www.aliexpress.com/item/LiitoKala-Lii-40A-3-7V-21700-4000mAh-14-8W-Li-ion-Rechargeable-Battery-with-Protected-PCB/32846442786.html
Is that a good price?

Not for TH with 26.32$ shipping.

If you are in the US, then it is the best deal on lithium ion cells I have found outside of bulk purchases.

Otherwise, I will continue ordering from there:
https://sunway.aliexpress.com/store/3173029?spm=2114.12010108.0.0.5de455e6OSrJv0

There are 2 colors of Liitokala Lii-40A yellow and pink ,are they the same?

HKJ: considering the high capacity of 20700&21700 cells, shouldn’t you put them in your 26650/32650 list rather then with the 18650 cells?

Thanks for all your testing: it really helps us out to decide what to buy!

Cheers,
Nico

The Lii-40A are already in both lists.

Or do you mean all 20700 and 21700?

Are you sure? Do you have the pink ones or know some place selling them?

It seems they are all yellow at the moment. If you have info about the pink, I would like to find out about it.

Many of the pink one.
https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20180612010401&SearchText=Liitokala+21700+

They are in both lists, but I usual forget to change the link at the bottom (It is auto generated to the 18650 list).
I have just added a link in the 18650 comparator to the 26650 comparator, hopefully this will help with this.

Okay, I see.

My suggestion is to buy the yellow since it was the one HKJ tested. The pink might be identical, but why take that chance?

I personally would just buy the yellow.