What's the c-rate of this cell?

[Trilemma]

Hi, I just got a bunch of cells of this model and I wanna know their c-rate https://rarecomponents.com/store/lg-m26-india-2600mah

According to the specs it has 10A continuous discharge rating and nominal capacity 2600mAh
So for the c-rate should I calculate this?

10/2.6=3.846

Thanks in advance

 

[ZeroEm]

Should be using "Amp Hour" not amps

LG M26 18650 Li-ion Cell - 3.65V - 2600mAh - 10A - INR18650M26

2600ma / 1000 = 2.6 is 1C

If i'm wrong someone will correct me.

by Trilemma » Aug 26 2021 3:42pm

Hi, I just got a bunch of cells of this model and I wanna know their c-rate https://rarecomponents.com/store/lg-m26-india-2600mah

According to the specs it has 10A continuous discharge rating and nominal capacity 2600mAh
So for the c-rate should I calculate this?

10/2.6=3.846

Thanks in advance

 

[Trilemma]

Should be using "Amp Hour" not amps

LG M26 18650 Li-ion Cell - 3.65V - 2600mAh - 10A - INR18650M26

2600ma / 1000 = 2.6 is 1C

If i'm wrong someone will correct me.

by Trilemma » Aug 26 2021 3:42pm

Hi, I just got a bunch of cells of this model and I wanna know their c-rate https://rarecomponents.com/store/lg-m26-india-2600mah

According to the specs it has 10A continuous discharge rating and nominal capacity 2600mAh
So for the c-rate should I calculate this?

10/2.6=3.846

Thanks in advance

Notice that here it's also 3.85 C rate for the same model but in different color https://voltaplex.com/lg-m26-18650-battery-inr18650m26

 

[ZeroEm]

They are both 2600mAH. I'm just looking at 1C. Different batteries can charge at different C-rates.

LG M26 18650 Battery, 2600mAh, 10A, 3.65V, Grade A Lithium-ion (INR18650M26)

C-rate (charge, max.) 0.96 C
Charge constant standard 1.25 A

That batter max charge rate is 2.49. As you can see they recommend half that. Which is .5 C

 

[ZeroEm]

The batteries you purchased have a spec sheet on that page. Down load it for safe keeping

https://www.batteryspace.com/prod-specs/11609.pdf

It states standard charge rate is .5C or 1250mA or 1.25a.

Max charge is 1C or 2500mA or 2.5a

That sheet will answer all your questions plus clues on C rates.

 

[thepronghorn]

Hi, I just got a bunch of cells of this model and I wanna know their c-rate https://rarecomponents.com/store/lg-m26-india-2600mah

According to the specs it has 10A continuous discharge rating and nominal capacity 2600mAh
So for the c-rate should I calculate this?

10/2.6=3.846

Thanks in advance

Yes you are correct. The continuous discharge rating is 10A which is equal to 3.846C.

 

[Silvaticus]

Yes you are correct. The continuous discharge rating is 10A which is equal to 3.846C.

However, the vast majority of cells live long only if they are discharged at nominal current values for most of their life.

 

[ZeroEm]

Yep, there I went and ignored his question and focused on charge rates and what 1C was. Had nothing todo with discharging.

 

[thepronghorn]

Yes you are correct. The continuous discharge rating is 10A which is equal to 3.846C.

However, the vast majority of cells live long only if they are discharged at nominal current values for most of their life.

True. While the cell can do 10A, it won't be very happy doing so. The spec says the fast discharge rate is 2.5A. I would aim to stay around that number if I were using this cell.

 

[E-HP]

According to the specs it has 10A continuous discharge rating

I must be reading a different spec sheet. I see a continuous discharge rating of 0.5A and a max discharge rating of 10A.

2.6 Standard Discharge Constant current 0.2C (500mA)
2.7 Max. Discharge Current 10A

0.19C; they rounded up to 0.2C

 

[ZeroEm]

by E-HP » Aug 26 2021 8:00pm

Trilemma wrote: ↑Aug 26 2021 3:42pm
According to the specs it has 10A continuous discharge rating

I must be reading a different spec sheet. I see a continuous discharge rating of 0.5A and a max discharge rating of 10A.

2.6 Standard Discharge Constant current 0.2C (500mA)
2.7 Max. Discharge Current 10A

0.19C; they rounded up to 0.2C

That's what I read!

 

[Trilemma]

So what's the verdict :?

 

[E-HP]

So what's the verdict :?

Hard to tell, since the constant discharge spec appears to be a controlled discharge, not maximum continuous discharge.
The max discharge looks like they would get the cells pretty hot, 75 degrees C on the spec sheet. I saw another site that said 5A continuous, but who know where that came from. You could test them to see how much you can draw without getting them too hot.
I saw this YouTube video, but it's more about how the cells hold up over time:
https://www.youtube.com/watch?v=gwExAsxg-Hc

 

[Trilemma]

So what's the verdict :?

Hard to tell, since the constant discharge spec appears to be a controlled discharge, not maximum continuous discharge.
The max discharge looks like they would get the cells pretty hot, 75 degrees C on the spec sheet. I saw another site that said 5A continuous, but who know where that came from. You could test them to see how much you can draw without getting them too hot.
I saw this YouTube video, but it's more about how the cells hold up over time:
https://www.youtube.com/watch?v=gwExAsxg-Hc

I agree, my guess is that if the cell was meant to stand in high discharge they wouldn't write this in the pdf specs:

4.1.3 Fast Charge / discharge condition
Cells shall be charged at constant current of 1,250mA to 4.2V with end current of 125mA. Cells shall be
discharged at constant current of 2,500mA to 3.0V. Cells are to rest 30 minutes after charge and 30
minutes after discharge.

 

[E-HP]

A C/20 rate means that battery capacity is calculated based on completely discharging it over the course of 20 hours. So, if you have a 1,000 amp-hour battery bank, charging or discharging at 50 amps would be a C/20 rate (1,000 Ah ÷ 50 A = 20 hrs.).

That's good information. What do you get when you apply that to the cells and spec sheet that the OP included in his first post?

 

[Chalo]

A C/20 rate means that battery capacity is calculated based on completely discharging it over the course of 20 hours. So, if you have a 1,000 amp-hour battery bank, charging or discharging at 50 amps would be a C/20 rate (1,000 Ah ÷ 50 A = 20 hrs.).

That's good information. What do you get when you apply that to the cells and spec sheet that the OP included in his first post?

Can't wait to see Marv's second post and whatever links and offers it contains!

 

[ZeroEm]

by Marvin5596 » Sep 02 2021 7:15am

A C/20 rate means that battery capacity is calculated based on completely discharging it over the course of 20 hours. So, if you have
official survey a 1,000 amp-hour battery bank, charging or discharging at 50 amps would be a C/20 rate (1,000 Ah ÷ 50 A = 20 hrs.).

Where does that link go i'm don't want to click on it?

 

[Chalo]

by Marvin5596 » Sep 02 2021 7:15am

A C/20 rate means that battery capacity is calculated based on completely discharging it over the course of 20 hours. So, if you have
official survey a 1,000 amp-hour battery bank, charging or discharging at 50 amps would be a C/20 rate (1,000 Ah ÷ 50 A = 20 hrs.).

Where does that link go i'm don't want to click on it?

Oh goody, he edited his first post. I don't have to wait! Spam and malware for everybody!

 

[ZeroEm]

I don't remember see that stuff until we started moving to different servers. There is more than ever of late. Are they bots or just spammers?

 

[DogDipstick]

5.96C

15.94A before damage. @ 60mOh.

0,93 volts will drop on a 16A load.

Per every serial connection. ( 2s1p, 1.86 volt dropped,... 4s1p, 3.72v dropped.. ect...Under load)

 

[markz]

I dunno, at times it got pretty bad but it never got out of control.
https://youtu.be/J06yQb4lbPk?t=26
edit - btw I added the youtube video at the specific time mark for the simple fact of Lemmy shrugging, plus its a cool tune to listen to.

I don't remember see that stuff until we started moving to different servers. There is more than ever of late. Are they bots or just spammers?

 

[Chalo]

I don't remember see that stuff until we started moving to different servers. There is more than ever of late. Are they bots or just spammers?

There were some huge outbreaks in the past, just spraying OT posts all over the place. Lately it's been pretty manageable, but the loathsome weasels have been trying harder to pass their garbage off as legitimate topical posts.