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 Bootes cell is a rewrap and both the current and capacity ratings are exaggerated. It is identical in performance and appearance to the 20A 2500mAh LG HE2. At 30A continuous this cell gets hot enough to boil water, 104°C. I am giving it a 20A/2500mAh rating since it performs identically to the HE2.
Continuous-Current Test Results
Pulsed-Current Test Results
These tests are done to show the performance of the cell at higher pulsed current levels. If you are running your mod at these levels be aware that you risk overheating, and possibly venting of, the battery if there is a malfunction or accidental pressing of your mechanical mod's button.
Bootes 40A 2800mAh vs LG HE2 Comparison
Comments
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 Bootes cell is a rewrap and both the current and capacity ratings are exaggerated. It is identical in performance and appearance to the 20A 2500mAh LG HE2. At 30A continuous this cell gets hot enough to boil water, 104°C. I am giving it a 20A/2500mAh rating since it performs identically to the HE2.
Continuous-Current Test Results
Pulsed-Current Test Results
These tests are done to show the performance of the cell at higher pulsed current levels. If you are running your mod at these levels be aware that you risk overheating, and possibly venting of, the battery if there is a malfunction or accidental pressing of your mechanical mod's button.
Bootes 40A 2800mAh vs LG HE2 Comparison
Comments
- At 10A continuous it reached about 2375mAh. This is far below what a 2800mAh cell should reach. It's good performance for a 2500mAh-rated cell operating at 10A so I am rating this cell at 2500mAh.
- At 15A continuous the temperature rose to 67°C. This is below the average temperature for a cell operating at its continuous discharge rating (CDR).
- At 20A continuous the temperature rose to 82°C. This is a couple degrees above the average temperature for a cell operating at its CDR but consistent with an LG cell at its CDR.
- At 25A continuous the temperature rose to 95°C. This is a significantly above the average temperature for a cell operating at its CDR.
- At 30A continuous the temperature rose to104°C. This is way, way above the average temperature for a cell operating at its CDR, indicating that we are operating above the cell's rating. The voltage is low and sagging a lot.
- At 35A continuous the temperature rose to 111°C. This is a preposterously high temperature for a cell to operate at. The voltage is uselessly low.
- At 40A continuous, the cell's rating, the cell's voltage quickly collapsed to 2.8V. This is clearly not a 40A cell.
- Another discharge at 20A shows clear damage to the cell, its voltage being lower than during the first 20A discharge. This was caused by just a single set of discharges up to its rating.
- I am setting a CDR of 20A for this cell. Its temperature is the same as the LG HE2 operating at its CDR and its appearance and performance are the same as a 20A/2500mAh HE2. 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 20A 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.
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
