These cells were purchased by me for the purposes of testing. To prevent any confusion with the eGo-type "batteries", I use the term "cell" here to refer to a single 18350, 18650, 26650, etc.
While the test results are hard data, the conclusions and recommendations I make based on these tests are only my personal opinion based on my criteria for setting a rating. Carefully research any cell 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.
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
The Sony VTC5A is a fantastic 25A 2500mAh battery. It runs at a higher voltage than the Aspire 1800mAh, VTC4/5, 25R, and HD2C and runs for almost as long as the VTC5. I want to do some more comparisons against other cells but this is probably one of the top three best 18650's.
Continuous-Current Test Results
Pulsed-Current Test Results
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
While the test results are hard data, the conclusions and recommendations I make based on these tests are only my personal opinion based on my criteria for setting a rating. Carefully research any cell 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.
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
The Sony VTC5A is a fantastic 25A 2500mAh battery. It runs at a higher voltage than the Aspire 1800mAh, VTC4/5, 25R, and HD2C and runs for almost as long as the VTC5. I want to do some more comparisons against other cells but this is probably one of the top three best 18650's.
Continuous-Current Test Results
Pulsed-Current Test Results
Comments
- At 10A continuous it reached a bit more than 2300mAh. This is average performance for a 2500mAh cell at 10A so I am rating this cell at 2500mAh.
- At 15A continuous the temperature rose to 61°C. This is significantly below the average temperature of a cell running at its continuous discharge rating (CDR).
- At 20A continuous the temperature rose to 73°C. This is a few degrees below the average temperature of a cell running at its CDR.
- At 25A continuous the temperature rose to 83°C. This is the upper limit for the temperature of a cell running at its CDR and is an indication that this is the cell's true rating. There's no sign of extra sag in the discharge curve that would indicate that the cell was being operated at above its rating.
- At 30A continuous the temperature rose to 92°C. This is way above the average temperature of a cell running at its CDR and is an indication that we're above the cell's true rating.
- At 35A continuous, what some feel is the VTC5A's rating, the temperature rose to 105°C. This is a ridiculously high temperature and is above my 100°C safety limit. The voltage has also sagged considerably. This is absolutely not a 35A cell.
- I am setting a CDR of 25A for this cell. Operating at that level would bring the temperature of this cell up to the upper limit for a cell operating at its CDR. 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 25A 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
