# SubOhmCell 35A 2800mAh? Nope, max 20A



## Mike (16/9/15)

I'm always skeptical of batteries that sound too good to be true. Seems like they never are.

Sourced from here
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Tested at 10A-25A constant current. This cell was purchased from IMRBatteries and donated for testing. To prevent any confusion with the eGo-type "batteries", I use the term "cell" here to refer to a single 18650, 26650, etc.




*Disclaimer*
The conclusions and recommendations I make based on these tests are only my personal opinion. Carefully research any battery you are considering using before purchasing.

Testing batteries at their limits is dangerous and should never, ever, be attempted by anyone who has not thoroughly studied the dangers involved and how to minimize them. My safety precautions are the ones I have selected to take and you should not assume they will protect you if you attempt to do any testing. Do the research and create your own testing methods and safety precautions.



*Bottom Line*
This is only a 15A+ cell that has almost 40% less capacity than the Samsung 25R at 20A. Runs much hotter than the 25R too.


*Test Results*




*Comments*_



_At 10A it reached a bit over 2300mAh. This is terrible performance for a 2800mAh-rated cell. I'm setting a capacity of 2500mAh for this cell.
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_At 20A the maximum temperature reached 86°C. This is very high and indicates that the cell is already operating beyond its CDR.
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_At 25A the temperature rose to 99° just before the test ended. The temperature then coasted up to 101°C. This exceeds my 100°C safety limit and very clearly demonstrates that this is not a 35A cell.
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_Tests were not done at 30A or 35A because my safety limit was already exceeded at 25A. The danger of cell venting would be very real at these high current levels in my opinion.
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_Five additional cycles at 20A showed essentially no loss in capacity or additional voltage sag. However, the temperature was too high to set 20A as the CDR.
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_I am setting a CDR of 15A+ for this cell. While it didn't appear damaged at 20A, it's temperature is too high. At 15A its temperature is the same as the 25R at its CDR. While operating any cell near its rated maximum current causes damage to the cell, I would expect decent cycle life from this cell at 15A+. I would not recommend operating this cell above 20A due to the high temperatures the cell reaches and the risk of venting._

Reactions: Like 1 | Informative 1


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## stevie g (16/9/15)

makes me laugh at the okes on the forum who thought they should buy the efest over the 25r because it is "newer tech".


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## zadiac (16/9/15)

Sprint said:


> makes me laugh at the okes on the forum who thought they should buy the efest over the 25r because it is "newer tech".



I get better performance and battery life from my efests than my 25R's. Always have.

Reactions: Disagree 1


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## Andre (16/9/15)

You have very good reason to be skeptical. The history of battery makers/sellers are not good at all. And still I see a few of our vendors selling batteries at 35A continuous discharge for a 3000 mAh battery, which we know is almost impossible at this stage - http://www.vapecartel.co.za/collections/18650-batteries/products/mxjo-18650-3000mah. And which this thread shows up. @KieranD, how sure are you of that 35A continues discharge claim?


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## Mike (16/9/15)

The MXJOs are actually some of the better batteries around at the moment! I can't speak about the 3000mAh, but the 2800 and 2500mAh which are rated at 35A did work out to around 20A continuous discharge rating - they even managed to top both the VTC5 and the 25R in terms of mAh while being just a little short on the current output comparatively.

Reactions: Agree 1


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## Necris (16/9/15)

the battery game is a messy one,looking into the brown lg 3000mah 20a batteries.
3000mah yes,achieved not by improving capacity,but by dropping minimum discharge to 2v...so essentially,you want that extra 500mah,you vape down to 2v.....who honeslty vapes that low.
Secondly,surely most reg devices cut you off at 2.5v too,so i see no real point to stray away from my 25r's

i will agree that efest has been good to me,never had issues on 3100mah nor 2500mah 35a,still have all of mine running after a year+
However,i would not use the 3100's at 0.2


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## Mike (16/9/15)

Necris said:


> However,i would use the 3100's at 0.2



I assume you mean NOT use?


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## Necris (16/9/15)

Mike said:


> I assume you mean NOT use?


correct,well spotted,thank you.
wow,i say that,but just realised i was using a mech to check hotspots on my fused alien,at 0.1 that 3100mah gets toasty quick.
safely on a reg box now


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## Andre (16/9/15)

Mike said:


> The MXJOs are actually some of the better batteries around at the moment! I can't speak about the 3000mAh, but the 2800 and 2500mAh which are rated at 35A did work out to around 20A continuous discharge rating - they even managed to top both the VTC5 and the 25R in terms of mAh while being just a little short on the current output comparatively.


No doubt they are good batteries, but why overstate the continuous discharge. Which is what Efest did and it really hurt them in the end.


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## Mike (16/9/15)

The thing is there's no set standard. Continuous discharge should be standardised and be used by all battery sellers, but if Efest sells a 35A (pulse - to their own testing standard) battery how can others compete while stating the most conservative rating. It's sad and works out badly for everyone involved.


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## phanatik (16/9/15)

Dammit!
Now which batteries are the "safe" to use?
I've been using efests exclusively, and recently got a VTC4 from the Mob.
Now i'm stressing...


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## Mike (16/9/15)

Depends on the ohms, but Smurfs, Zombies, VTC5s are the safest. As long as you're building above 0.25 ohms, you're pretty much safe with any decent battery (below 3000mAh)


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## Andre (16/9/15)

Mike said:


> The thing is there's no set standard. Continuous discharge should be standardised and be used by all battery sellers, but if Efest sells a 35A (pulse - to their own testing standard) battery how can others compete while stating the most conservative rating. It's sad and works out badly for everyone involved.


Efest do now on their new batteries give the correct information.

Reactions: Informative 1


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## Andre (16/9/15)

phanatik said:


> Dammit!
> Now which batteries are the "safe" to use?
> I've been using efests exclusively, and recently got a VTC4 from the Mob.
> Now i'm stressing...


No need to stress - just use the chart in this thread as a guide.

Reactions: Useful 2


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## phanatik (16/9/15)

Andre said:


> No need to stress - just use the chart in this thread as a guide.


Thanks a mill Andre

Reactions: Like 1


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## Yoda (16/9/15)

Best thing to do is:
Step 1. Get some smurfs and a series unregulated box mod
Step 2. Use some Google-fu and find http://www.steam-engine.org
Step 3. Use the Ohms law calculator and build a pair of 0.6 dual coils and a pair of freshly charged batteries 
Step 4. vape at a casual 100 watts at 7.8 volts (accounted for voltage drop) and only 13A being pulled.
Step 5. Get more smurfs

Reactions: Funny 1


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## phanatik (16/9/15)

Yoda said:


> Best thing to do is:
> Step 1. Get some smurfs and a series unregulated box mod
> Step 2. Use some Google-fu and find http://www.steam-engine.org
> Step 3. Use the Ohms law calculator and build a pair of 0.6 dual coils and a pair of freshly charged batteries
> ...


Right, now.... Where can i get some Zombies/Zombie Smurfs? (the Green Smurfs)


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## Yoda (16/9/15)

@phanatik i have not used them, nor have i searched for them, just get some samsung 25r (blue smurfs) they are widely available and also reliable

Reactions: Agree 2


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## zadiac (16/9/15)

@Sprint , you can disagree with me, but I have tested it over and over with all my batteries. My Efests perform better and hold their charge. Even two days after charge, my efests are still at 4.2v while my smurfs go down to 4.1v without using it. I can go a full 10ml bottle on my VR woodmod with my efests, but not with my smurfs. Around 6ml my vape starts to get cold and the flavor drops. With the efests, the vape is still warm and full flavor until the last drop.
My efests perform way better than my smurfs. I only use the smurfs in the VR when I have to.


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## stevie g (16/9/15)

if you run low wattage but as the tests show under high discharge the efest 2800mah 35a sags more than the 25r. Same cell as the one tested here.


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## stevie g (16/9/15)

as per this review http://www.ecigssa.co.za/efest-35a-2800mah-18650-bench-test-results.t14236/


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