These cells were purchased for the purpose of testing by me. 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 statements, 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 cells 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.
A note regarding current ratings and my testing
If the cell has only one current rating number on it, or if it says "max discharging current" then I have to assume that the company is stating that the cell can be discharged at that current level in any way, including continuously.
Bottom Line
This AOSO cell is a rewrap with a shamefully exaggerated current rating. Like the MXJO 20A 3500mAh cell it is identical in performance and appearance to the 10A 3500mAh LG MJ1. Also like the MXJO a 15A continuous discharge gets the AOSO hot enough to boil water. At the AOSO's 25A rating it only delivers about 10mAh down to 3.2V. That is not a typo...10mAh.
Continuous-Current Test Results (with comparison to LG MJ1)
Pulsed-Current Test Results
I'm not wasting my time pulse testing another MJ1 rewrap. See the MXJO 20A 2500mAh cell test report for the pulse discharge graph...
MXJO 20A 3500mAh 18650 Bench Test Results...just another rewrapped 10A battery
Comments
To see how other cells have tested and how hard you can safely push them, check out these links:
List of Battery Tests | E-Cigarette Forum
18350 Safety Grades and Pulse Performance Data | E-Cigarette Forum
18650 Battery Ratings -- Picking a Safe Battery to Vape With | E-Cigarette Forum
26650 Safety Grades and Pulse Performance Data | E-Cigarette Forum
Disclaimer
The statements, 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 cells 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.
A note regarding current ratings and my testing
If the cell has only one current rating number on it, or if it says "max discharging current" then I have to assume that the company is stating that the cell can be discharged at that current level in any way, including continuously.
Bottom Line
This AOSO cell is a rewrap with a shamefully exaggerated current rating. Like the MXJO 20A 3500mAh cell it is identical in performance and appearance to the 10A 3500mAh LG MJ1. Also like the MXJO a 15A continuous discharge gets the AOSO hot enough to boil water. At the AOSO's 25A rating it only delivers about 10mAh down to 3.2V. That is not a typo...10mAh.
Continuous-Current Test Results (with comparison to LG MJ1)
Pulsed-Current Test Results
I'm not wasting my time pulse testing another MJ1 rewrap. See the MXJO 20A 2500mAh cell test report for the pulse discharge graph...
MXJO 20A 3500mAh 18650 Bench Test Results...just another rewrapped 10A battery
Comments
- At 5A continuous it reached about 3150mAh. This is a bit better than average for these high internal resistance, high capacity 3500mAh cells at 5A so I am rating this cell at 3500mAh.
- At 10A continuous the temperature rose to 72°C. This is a few degrees below the average temperature for a cell operating at its continuous discharge rating (CDR) but normal for the MJ1.
- At 15A qcontinuous the temperature rose to 100°C, my safety limit. This is way, way above the average temperature for a cell operating at its CDR, indicating that we are operating above the cell's actual rating. The voltage is low and sagging a lot.
- At 20A continuous the voltage sag was huge and the temperature rose to 96°C even though the discharge was very short.
- At 25A, the AOSO's rating, the voltage plunged down quickly to a useless level. This is clearly not a 25A cell.
- I am setting a CDR of 10A for this cell. Its temperature is the same as the LG MJ1 operating at its CDR and its appearance and performance are also the same as the MJ1. While operating any cell near its rated maximum current level causes damage to the cell, I would expect decent cycle life from this cell at 10A continuous.
- I have included pulsed discharges but I haven't set pass/fail standards for pulse testing yet. The discharges were done at 5sec on/30sec off, down to 2.5V. One chart shows the entire discharge at each level. The other chart is zoomed in to show the first 5 minutes to make it easier to see the voltage sag at different current levels.
To see how other cells have tested and how hard you can safely push them, check out these links:
List of Battery Tests | E-Cigarette Forum
18350 Safety Grades and Pulse Performance Data | E-Cigarette Forum
18650 Battery Ratings -- Picking a Safe Battery to Vape With | E-Cigarette Forum
26650 Safety Grades and Pulse Performance Data | E-Cigarette Forum
