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Original article: https://www.thunderheartreviews.com/2019/01/queen-battery-qb26800-6800mah-20a-big.html
26800 is a new format of cylindrical cells. It means 26mm in diameter and 80mm in length. Queen Battery QB26800 is rated at 6800mAh and can be discharged at up to 20A continuously.
The battery was bought from Queen Battery which is my reliable supplier of genuine cells and tested with ZKETECH EBC-A20 and a self-made battery holder. It's a PC-connected battery tester supporting 4-wire measuring and discharging at up to 20A.
I've used version 3.0 of my battery holder based on 0.5mm thick pure copper terminals
I've followed all the prescriptions of the IEC61960-2003 standard concerning battery's capacity measurement. Before each discharging cycle the battery was charged at standard charge current mentioned in its datasheet to charge end voltage. Before each discharging or charging i've held a 1-1.5hr pause. The environment temperature was 23.0-24.5°C. To be sure in results i've done each test minimum twice (usually 3-4 times).
Queen Battery QB26800 6800mAh
The cell is marked as QB26800 6800mAh 3.7V. No data about production date or batch number.
The main specifications from QB26800's datasheet*:
Capacty: 6800mAh
Nominal voltage: 3.6V (on the battery there is a 3.7V notice)
Standard charge current: 6.8A (1C)* (i charged at 5A, which is the max charge current of my tester)
Maximum charge current: 13.6A (2C)
Charge cut-off current: 340mA (0.05C)*
Charge end voltage: 4.20V
Max continuous discharge: 20.4A (3C)
Max pulse discharge: 34A (5C) for <30s
Discharge cut-off voltage: 3.0V*
AC impedance at 1KHz: ≤10mΩ*
Weight: 121±3g
*data from datasheet version available at the moment of testing.
Measured initial DC IR at 6.8A in fully charged condition was 16±0.3mΩ
Measured weight of the tested cell was 116.18g
Capacity test results:
Pay attention to the discharge cut-off voltage - it's 3.0V* while the majority of cylindrical Li-ion cells' end on 2.5V or 2.75V.
At 0.2C (1.36A) QB26800's capacity appeared to be noticeably higher than 6800mAh - it's 6930mAh. The curves look good and smooth. At 20A the capacity was still above 6200mAh and the energy more than 20Wh.
Of course the results could be higher if it was discharged down to 2.5V but once the manufacturer says cut-off is at 3.0V i have to use that number.
The cell's length could be a problem for those who are going to charge it in a charger but i think these batteries will mostly be used in battery packs so the length is not a problem.
Look at it in comparison with 21700 and 18650 cells:
Update!
The test was done using the very first version of datasheet available at the moment but later it was updated twice and here is a table with differences between datasheet versions:
Here is the video version of this review:
Check out my YouTube channel for batteries, chargers and other stuff reviews.
I've launched my blog where you can find all my reviews in one place. Every new test/review will be first published on YouTube and in the blog. I'll be happy to see new subscribers, comments, suggestions and just your thoughts.
26800 is a new format of cylindrical cells. It means 26mm in diameter and 80mm in length. Queen Battery QB26800 is rated at 6800mAh and can be discharged at up to 20A continuously.
The battery was bought from Queen Battery which is my reliable supplier of genuine cells and tested with ZKETECH EBC-A20 and a self-made battery holder. It's a PC-connected battery tester supporting 4-wire measuring and discharging at up to 20A.
I've used version 3.0 of my battery holder based on 0.5mm thick pure copper terminals
I've followed all the prescriptions of the IEC61960-2003 standard concerning battery's capacity measurement. Before each discharging cycle the battery was charged at standard charge current mentioned in its datasheet to charge end voltage. Before each discharging or charging i've held a 1-1.5hr pause. The environment temperature was 23.0-24.5°C. To be sure in results i've done each test minimum twice (usually 3-4 times).
Queen Battery QB26800 6800mAh
The cell is marked as QB26800 6800mAh 3.7V. No data about production date or batch number.
The main specifications from QB26800's datasheet*:
Capacty: 6800mAh
Nominal voltage: 3.6V (on the battery there is a 3.7V notice)
Standard charge current: 6.8A (1C)* (i charged at 5A, which is the max charge current of my tester)
Maximum charge current: 13.6A (2C)
Charge cut-off current: 340mA (0.05C)*
Charge end voltage: 4.20V
Max continuous discharge: 20.4A (3C)
Max pulse discharge: 34A (5C) for <30s
Discharge cut-off voltage: 3.0V*
AC impedance at 1KHz: ≤10mΩ*
Weight: 121±3g
*data from datasheet version available at the moment of testing.
Measured initial DC IR at 6.8A in fully charged condition was 16±0.3mΩ
Measured weight of the tested cell was 116.18g
Capacity test results:
Pay attention to the discharge cut-off voltage - it's 3.0V* while the majority of cylindrical Li-ion cells' end on 2.5V or 2.75V.
At 0.2C (1.36A) QB26800's capacity appeared to be noticeably higher than 6800mAh - it's 6930mAh. The curves look good and smooth. At 20A the capacity was still above 6200mAh and the energy more than 20Wh.
Of course the results could be higher if it was discharged down to 2.5V but once the manufacturer says cut-off is at 3.0V i have to use that number.
The cell's length could be a problem for those who are going to charge it in a charger but i think these batteries will mostly be used in battery packs so the length is not a problem.
Look at it in comparison with 21700 and 18650 cells:
Update!
The test was done using the very first version of datasheet available at the moment but later it was updated twice and here is a table with differences between datasheet versions:
Here is the video version of this review:
Check out my YouTube channel for batteries, chargers and other stuff reviews.
I've launched my blog where you can find all my reviews in one place. Every new test/review will be first published on YouTube and in the blog. I'll be happy to see new subscribers, comments, suggestions and just your thoughts.
