Cycle life tests of High Energy density cylindrical cells

[ak136]

21700 7Ah at 3.35V nominal? What chemistry is that?

 

[neptronix]

Can't believe we're already at 325whrs/kg!

 

[BatteryMooch]

Kumyang has licenced StoreDot's technology and they have listed some curious new cells on their website:

Interesting that the nominal voltage drops on their highest and lowest capacity cells.
All still in development so maybe that has something to do with it.

 

[BlueSwordM]

21700 7Ah at 3.35V nominal? What chemistry is that?

High Si anodes tend to cause that.

 

[sorg]

Are these Linshen LR2170SK available in Europe ?

 

[BlueSwordM]

Are these Linshen LR2170SK available in Europe ?

No sadly.
I've been chatting with distributors, and they're NOW ending pre-production, so supply is low and difficult to get.

The BAK 58E, on the other hand, is actually available to purchase in bulk at actually reasonable prices.

 

[Pajda]

The BAK 58E, on the other hand, is actually available to purchase in bulk at actually reasonable prices.

Is it? I was very curious about this particular BAK 58E cell, unfortunately it was not available anywhere. I'll try asking Vapcell again.

 

[BlueSwordM]

Is it? I was very curious about this particular BAK 58E cell, unfortunately it was not available anywhere. I'll try asking Vapcell again.

Yes: 2500pcs at 2.95$USD each.

 

[Pajda]

Small update

Update:
- updated both 5300mAh+ charts
- updated 3100mAh+ chart at 100% DoD in 18650 format for comparison with LFP JGNE 2200mAh (third post)

 

[Pajda]

Yes: 2500pcs at 2.95$USD each.

Nice, Vapcell probably already has them too, waiting for a quote.
Btw, during the search I found samples of BAK N21700CK-55E available in Poland, so I will order them too.

 

[Pajda]

Samples of BAK N21700CK-55E arrived today, I'll start testing them right after Easter. BAK 58E should hopefully arrive by the end of the month.

 

[freesty]

There is a Tenpower INR18650-35HE listed at nkon for a interesting price. Might worth a test? with 50grams pretty heavy for a 18650.

 

[Pajda]

There is a Tenpower INR18650-35HE listed at nkon for a interesting price. Might worth a test? with 50grams pretty heavy for a 18650.

Did I miss them? Nkon says they have them on pre-order with delivery at the earliest 04-06-2025.

By the way BAK 58E has been stocked in Poland and ordered today.

 

[freesty]

Did I miss them? Nkon says they have them on pre-order with delivery at the earliest 04-06-2025.

By the way BAK 58E has been stocked in Poland and ordered today.

No, I just found them listed for the first time for pre-order.

 

[Pajda]

Small update

Update:
- updated both 5300mAh+ charts + LFP JGNE 2200mAh

 

[Pajda]

I noticed that Vapcell recently released their new products

Vapcell N41 @ 4050 mAh in 18650 New Release Highest Capacity Vapcell N41 18650 3.7v 4050mah 10a Li-ion Rechargeable Battery For Flashlight - Buy 18650 4050mah Li-ion Battery highest Capacity Vapcell N41 18650 4050mah 18650 3.7v 4050mah 10a Product on Alibaba.com
Vapcell F63 @ 6250 mAh in 21700 https://www.alibaba.com/product-det...html?spm=a2700.shop_pl.41413.8.479c7121B71qc1

 

[riba2233]

Not sure if you noticed these, they are pretty cheap so might be worth looking at:

** INR21700-M52VT 5200mAh - 15A

Product: LG INR21700 M52VT Rated Voltage: 3.69 V Max. Charging Voltage: 4.20 V Max. Charging current 0 ~ 25℃ 0.3 C (1,500 mA) 25 ~ 45℃ 0.7 C (3,500 mA) Weight: 67.4 ± 1.0 g Diameter: ≤ 21.27 mm Height: ≤ 70.60 mm

www.nkon.nl

 

[Pajda]

These LG M52s are out of stock for several months. I couldn't find them anywhere else

 

[BatteryMooch]

I noticed that Vapcell recently released their new products
Vapcell N41 @ 4050 mAh in 18650
Vapcell F63 @ 6250 mAh in 21700

I’ve got a pair of each in transit and am looking forward to seeing how they perform. Vapcell can be a little optimistic with capacity ratings, “rounding up” datsheet ratings, but their current ratings are usually pretty close (but might be temperature-limited).

 

[BlueSwordM]

I noticed that Vapcell recently released their new products

Vapcell N41 @ 4050 mAh in 18650 New Release Highest Capacity Vapcell N41 18650 3.7v 4050mah 10a Li-ion Rechargeable Battery For Flashlight - Buy 18650 4050mah Li-ion Battery highest Capacity Vapcell N41 18650 4050mah 18650 3.7v 4050mah 10a Product on Alibaba.com
Vapcell F63 @ 6250 mAh in 21700 The Highest Capacity 21700 Battery Real Rating Vapcell F63 21700 3.7v 6250mah 12.5a For Power Tools And Flashlight - Buy 21700 3.7v 6250mah 12.5a 21700 Cell 6250mah vapcell 21700 6250mah Battery Product on Alibaba.com

These look nice.

Anyway, those LFP cell numbers are honestly awful for a "modern" LFP cell.

It'd likely to do better in a larger package if made by another manufacturer.

 

[freesty]

Would you consider the EVE 35V as a good energy cell with a reasonable price tag? With 100% DoD the cycle life is reduced, but with 90% which is more reallife usage, the lifespan is fine for most usecases.
Or are there better ones?

 

[BlueSwordM]

Would you consider the EVE 35V as a good energy cell with a reasonable price tag? With 100% DoD the cycle life is reduced, but with 90% which is more reallife usage, the lifespan is fine for most usecases.
Or are there better ones?

The best low price high energy cells are likely to be the EVE 50E, Samsung 50G, and other similar 21700 cells in this category.

I would avoid going with 18650s these days since smaller cells increase pack building costs and 21700s get most of the advances these days.

 

[freesty]

Ok, I agree for building a new battery from scratch. But replacing defective 18650 cells its easier to stay 18650.

 

[BlueSwordM]

Ok, I agree for building a new battery from scratch. But replacing defective 18650 cells its easier to stay 18650.

Well, if that's the case, EVE 33V, EVE 35V, Samsung 35E, Molicel M35A, BAK NCR18650CG-35E (better electrolyte alternative to the Samsung 35E), Lishen LR1865HB are all great choices, althought I'd pick the newer cells 18650 like the Molicel M35A, EVE 35V and BAK's variant would be your best bet.

 

[Pajda]

Small update

Update:
- updated table and 1C discharge chart with BAK 55E and 58E results. BAK 58E, despite its higher capacity, has a slightly worse energy density than 55E. Cycle life tests already running.