Test/review of Samsung INR21700-30T 3000mAh (Gray)

Samsung INR21700-30T 3000mAh (Gray)

Official specifications:

  • Standard discharge capacity: min. 3000mAh (1.5A charge 0.1A cut-off, 0.6A discharge, 2.5V cut-off)

  • Rated discharge capacity: min. 2650mAh (4A charge 0.1A cut-off, 10A discharge, 2.5V cut-off)

  • Nominal voltage: 3.6V

  • Charge voltage: 4.2V

  • Standard charge: 1.5A charge 0.1A cut-off

  • Rated charge: 4A charge 0.1A cut-off

  • Max. continuoys discharge: 35A at 25°C

  • Discharge cut-off voltage: 2.5V

  • Cycle life: 250 cycles to 60% at 35A discharge.

  • Cell weight: 69.0g max

  • Cell dimension: Height: Max: 70.40mm, Diamter: max. 21.22mm

  • Operating temperature (surface): Charge 0°C ~ 50°C (Recommended <45°C), Discharge –20C° ~ 80°C (Recommended <60°C)

  • Storage temperature: 1 month: –20°C ~ 60°C, 3 months: –20°C ~ 45°C, 1 year: –20°C ~ 25°C

This is the new battery size that is slightly larger than 18650 cells. This cell is a high current cell with moderate capacity.

This battery can easily handle 30A and more with constant capacity and perfect tracking between the cells.
I did try a 50A discharge, but my battery holder melted before I was finished with the first trace.

The battery gets warm at 30A, but not too warm.

In this discharge the battery is in free air, i.e. it has better cooling.


This battery is a very good battery and the best high current cell I have tested to date. At lower current there is no reason to use this cell, only when the current is above 10A is this cell interesting.

Notes and links

The batteries was supplied by ENERDan for review.

My test stations is only equipped to handle up to 30A, this means higher current must be done on other equipment.

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
Compare to 26650 and other batteries

Is this the same battery as a 30Q only bigger?

If it had been exactly the same, the capacity would have increased due to the size increase.

Thanks for the test HKJ. Impressing cell!

I spit water on my keyboard when I read this.

Comparing it at 20A and 30A to its high current 3Ah 18650 peers like the Sony VTC6 and the Samsung INR18650-30Q, the big advantage seems to be much cooler operational temperatures. I don’t think any of the 18650 cells can be safely used at over 18A-19A in continuous use. Looks like the INR 21700 can be safely used at 25A for continuous use. The e-cig guys will be loving this 21700 cell.

It can be used at safely at 35A as long as it have free air around it (A metal holder can be very close to free air) (It did not get too hot in my 40A test). That is the reason I call it the best high current cell I have seen.

I did not know if you meant “best” high current cell compared to only 18650, or to any cell - so I looked up Liitokala INR26650-50A and the 30T performs much better at high current. Very impressive.

Very impressive indeed. If the next generation includes higher capacity, sort of like the change from the 25r to the 30q, they will be really amazing.

I hate it, it means I have to do some extra work.

A new battery holder looks like this:

But I change the connecting wires and this means when it looks like this I have work to do:

WOW this 30T is one serious battery, thank you for testing and um…

Sacrificing!! :open_mouth:

Nice cell. That’s an interesting battery holder. Did you buy it or make it? Any links if you bought it please?

Samsung 30T’s motto: “HKJ’s equipment can’t handle my power.”
How’s that for advertising?

Probably the best e-bike cell it seems. Unless you have an underpowered EU-compliant motor.

Incredible! I want one!! Or 20! Excellent job once again HKJ!!

Samsung introduced their 21700 e-bike battery in 2016: 4750mAh and 9A max discharge.

Wow, 4750 and 9A. That does seem like an ideal e-bike cell - lots of capacity and just enough current. What size / form factor?

It is from fastech: https://www.fasttech.com/products/1425/10024652/5339401

Cylindrical, 21mm diameter and 70.0mm hight. In case that was the question.

Where in the world can I order these cells? I’ve been using the Sanyo 20700B, but I really want to get my hands on those. Any info or links would be greatly appreciated.