DIYAKKU | Do It Yourself Akku - Portal

Aliexpress Liitokala “Samsung 30Q” Li-Ion Cell Review

Fri, 10 Jun 2022 22:16:58 +0000

30Q.jpg (Größe: 240.72 KB / Downloads: 2)

Preface
I was in need of 18650s recently, and there was a great price on these Liitokala 30q cells at Aliexpress. I like 30q cells, and I like good prices, so I bought 8 of these cells. There was a bunch of discussion on BLF and places regarding whether these cells are “real” or not. Read on to find out!
As always, click for bigger images!!!

Official Specs (from the listing!!)

Model: ICR18650-30Q
Type: Li-Ion 18650
Nominal Capacity: 3000mah（2900-3000mah）
Nominal Voltage: 3.7V
Weight: 45g±1g
Rechargeable Battery: Yes
Rechargeable Times: Up to 500 times
internal resistance: ≤50mΩ
Limited Charge Voltage: 4.2v
Working Voltage: 2.75-4.2V
Size: 65.5mm x 18.5mm (Diameter)
Place of Origin: South Korea

And here’s a spec sheet from Samsung themselves.
Price
I paid $22.30 for eight of these, but it looks like the price has gone down a bit since I purchased. Now, 10 can be had for $22.65!! These were being sold specifically by liitokala Factory Store. This review pertains only to cells from liitokala Factory Store!!

Short Review
These cells feel like real 30Q cells. They look like real 30q cells. They’re high quality in appearance. However, they fail on the testing side of things for being real Samsung 30q cells. But. But, they aren’t bad cells for high capacity low current cells! Note that the listing specifically says they’re good for E-cig use. I would absolutely not use these in e-cigs!!
Long Review
Package
The package I purchased included cells in a plastic case, like the one seen below (I have a bunch of these, I honestly can’t remember which one specifically these cells arrived in.)

It’s a nice little case, made for only 18650s, and fits 4 perfectly. There’s a metal hook on the back, and the lid latches closed snugly (and is easy to open.)

Build Quality
As I said above, these cells have a very good build quality – they look and feel just like the real thing.

They even have a LiitoKala QR code, which accurately delivers the user to Liitokala.com.cn. This is not a proof of authenticity, however.

It’s probably at exactly this point where head scratchers will begin head scratching….

That’s right, these “30q” cells have a four leg positive terminal. Unfortunately this isn’t something that’s pictured or stated in the spec sheet (as far as I noticed), but genuine 30q cells have a three leg positive terminal. Hmmmmm….

Size

Testing
Being that these cells are from Aliexpress, and knowing that …. that might not be the best place to buy high current cells, I was wary of testing these cells at high currents. Still they seemed to live as I increased the current tests, so I went on.
I’ve tried to keep the scales similar, so over time the charts will be generally comparable.
Click these for biggie sized!!
Discharge tests
Hour discharge time doesn’t tell us much.

The minutes test gives us some much needed detail regarding the high current tests. While the time of 8 minutes for 15A or 4 minutes for 20A is not necessarily unheard of, look at that voltage drop. Immediately when the load hits, the voltage drops to a staggering <3.2V.

Capacity
Here’s another decent indicator that these cells might not be genuine. The specification for these cells is a discharge to 2.5V, at 0.2A. I’ve not even discharged them to 2.5V, and the capcacity is already well over the rated 2950mAh. Not an insignificant difference either – in every test by HKJ, these cells tested below 3000mAh.

Energy
Another issue can be seen below, with the Energy graph. On a good cell, these values would be at least somewhat close. Again comparing to HKJ’s values, which were all within a couple of Wh of each other – these on the Aliexpress cell are over a massive range, from around 3Wh to over 11Wh. This is probably due to a much higher internal resistance than specification.

Bounce
This is a new section, and I added it just because I think it’s interesting. “Bounce back” is what the cell voltage does when the cell rests after a discharge. Interestingly, after heavy discharge rates, the cell bounces back higher. This corresponds to a discharge amount of less energy, and does mean that there’s energy left in the cell. So if I selected the cell with the highest bounce back (ie the cell that was discharged at the highest current), then discharged it to 2.8V at 0.2A, I’d still find that there was a lot of energy still in the cell.

Charge test
Still working on the best format for this chart. I’ll likely start charging at 1.5A, 2A, and 3A when applicable.

Power, Constant

Internal Resistance
As can be seen on the chart below, the IR for this cell is much too high. I think the IR should be something like ≤ 26mΩ.

Conclusion
While I don’t like these being called 30q cells, I do think they’re fine for low current needs. The capacity is good, and the cost is very low. I don’t like them being misrepresented so that alone is probably a “don’t buy” from me, but still, 3000mAh for $2.25 per cell is a good deal. Just don’t use them over 3 to 5A discharge or so.
Note that the listing specifically says they’re good for E-cig use. I would absolutely not use these in e-cigs!! These were being sold specifically by liitokala Factory Store. This review pertains only to cells from liitokala Factory Store!!

Samsung INR18650-35E 3500mAh (Pink)

Fri, 10 Jun 2022 22:00:36 +0000

Official specifications:

Nominal capacity: 3500mAh
Minimum capacity: 3350mAh
Nominal voltage: 3,6V - 3,7V
Charging voltage: 4,2V
Discharge current: 8A
Maximum discharge current: 13A
Charge current: 0,6C 2000mA
Discharge end voltage: 2,65V
Pluspol: FlatTop
Chemistry: LiNiCoAlO2
Diameter: 18,55mm ± 0,1
Height: 65,25mm ± 0,15
Weight: 48g ± 1

This is one of the new high capacity cells.

The discharge curves has good tracking.
At 15A the B track stops just after 2.3Ah, this is because my battery holder melts (I hope this is fixed now).

15A is definitly too high current for this cell. The cell temperature is above 75°C (25°C ambient + 50°C temperature raise). Logfile says 87°C for A cell.

On this chart it is obvious how the heat improves the performance at 15A.

Due to the melted battery holder I did only do this for one cell.

Conclusion

The cell looks very good, it has lot of capacity and can handle some current, but I will not recommend it above 10A.

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

Test/review of LiitoKala INR26650-50A 5000mAh (Black)

Fri, 10 Jun 2022 21:58:55 +0000

Official specifications:

Nominal Capacity: 5000mah(4900-5000mah)
Nominal Voltage: 3.7V
Weight: 95g±1g
Rechargeable Battery: Yes
Rechargeable Times: Up to 500 times
internal resistance:
Limited Charge Voltage: 4.2v
Working Voltage: 2.75-4.2V
Size: 65.5mm x 26.5mm (Diameter)
Place of Origin: China HongKong

LiitoKala has updated the wrapper for their battery, is the battery inside still the same?

Performance looks good up to 15A-20A

The cell got very hot at 30A, this is too much for continuous discharge.

Conclusion
The performance is slightly below the old version, but it is still a very good performance.
Notes and links
Old LiitoKala INR26650-50A 5000mAh (Cyan)(link is external)
How is the test done and how to read the charts(link is external)
How is a protected LiIon battery constructed(link is external)
More about button top and flat top batteries(link is external)
Compare to 18650 and other batteries(link is external)

36V Akku bauen: 10S3P oder 10P3S

Fri, 10 Jun 2022 20:06:57 +0000

Moin,

muss für den E-Roller meinen Tochter einen 36V Akku bauen. Strombedqarf max. 12A.
Baue ich das als 10S3P oder als 10P3S. Bislang habe ich immer 10S3P gebaut, ohne das aber zu hinterfragen.
Schneller ginge aber wohl ein 10S3P.

Ich glaube, dass wurde hier schon mal diskutiert, ich finde aber den Beitrag nicht, sorry.

Gruss

KFKA - kurze Frage, kurze Antwort

Fri, 10 Jun 2022 20:04:35 +0000

Nach kurzer Absprache möchte ich diesen Thread eröffnen.

Ich kenne solche Themen bereits aus anderen Foren, dort kann man für Kleinigkeiten seine Frage stellen, die keinen eigenen Thread bedürfen oder es keinen existierenden Thread gibt wo man fragen könnte.

Da wir in der Plauderecke sind können hier Themen über Fahrräder/Pedelecs, aber auch Themen ohne jeglichen Bezug dazu besprochen werden.

Ich habe gerade keine konkrete Frage, aber wollte zumindest den Versuch wagen ob Interesse für diesen Thread besteht.

Früher war alles besser oder doch nicht?

Fri, 10 Jun 2022 19:59:32 +0000

Ich habe das Gefühl das alles schneller gehen muss und die jungen Leute heute sich in gewissen Situationen ohne Handy nicht mehr zu helfen wissen.
Meine Tochter hatte mal zu mir gesagt, sie beneide mich weil ich ohne Handy aufgewachsen bin.

Bafang BBS02 fährt nur noch mit Daumengas

Fri, 10 Jun 2022 19:58:19 +0000

Hallo,
habe einen Bafang BBS02 Mittelmotor der nur noch mit Daumengas fährt, auf dem Display ist auch keine Fehlermeldung. Die Bremssensoren funktionieren auch, hat jemand schon mal so eine Fehler gehabt und eine Idee wie sich das beheben lässt.
Gruß

Hailong Akku Feuchtigkeit vorbeugen?

Fri, 10 Jun 2022 19:37:57 +0000

Hallo Gemeinde!

Nachdem sich mein Yose Power 36V Hailong Akku nicht mehr vollständig hat Laden lassen, Ladeschlussspannung nur noch 37.99V, hat mich der Support von Yose gebeten die Spannung der einzelnen Blöcke zu messen.
Nach dem öffnen, konnte ich das Problem direkt erkennen. Es war Feuchtigkeit im Akku, die Kontakte teilweise verrostet und eine Zelle schon durchgebrannt.

Jetzt würde ich gern wissen, wer und wie Ihr eure Akkus eventuell vorsorglich abgedichtet habt?
Ich habe bereits einen neuen Akku gekauft und möchte dem vorsorgen.

Probleme mit Akku 500 Watt

Fri, 10 Jun 2022 19:36:53 +0000

Hallo zusammen,

wie kann ich den meinen Akku überprüfen?

Über den Knopf am Akku 30 sek drücken zeigt er noch alle 4 Leuchten an, was angeblich 75% bis 100% Ladekapzität angibt.

Ich habe das Gefühl, dass der Akku von 60% immer gleich auf 40% springt.

Wie ist so ein Akku aufgebaut?

Sind da z.B. 5 Akku Zellen drin und davon könnte eine defekt sein?

Kaufberatung gefederte Sattelstützen / Federsattelstützen

Fri, 10 Jun 2022 19:17:26 +0000

Mein Bike ist völligst ungefedert, was mich schon recht übel stört. Möchte mindestens eine gefederte Sattelstütze montieren.

Welche könnt Ihr da empfehlen? Über 50€ sollte sie auf keinen Fall kosten.