The two cells tested were donated for the purposes of testing by City of Cloud (Batteries). Thank you! 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
This Sanyo is one of the new generation of slightly larger cylindrical cells being brought to the market primarily for automotive use. It is 20mm in diameter and 70mm long, a 20700 battery. Other sizes and designations for similar cells from other manufacturers include 20650 and 21-70.
I am rating this cell at 16A 4000mAh. It runs a few degrees hotter than the HG2 (which is why the Sanyo has a lower rating) but at 10A and 20A continuous down to 3.2V the Sanyo lasts about 25% longer.
There is also a Sanyo 20700A cell which is rated at 3100mAh and about 30A. You'd have the capacity of a VTC6/30Q/HG2 plus a 30A rating for just a small increase in battery size.
Either of these Sanyo's could be a very good choice to 3D print a custom battery sled for. City of Cloud was kind enough to send me a couple of their samples of the 20700B for this testing but no 20700A's were available. I hope to get a couple of the 20700A's soon.
I don't know if any of these larger cells will eventually replace the 18650 but the Sanyo 20700B is hopefully just the first alternative cell that I'll be testing that offers a good current rating and extra capacity over our 18650's for just a small increase in size.
Continuous-Current Test Results
Pulse-Current Test Results
Sanyo 20700B Specifications
Comments
List of Battery Tests | E-Cigarette Forum
https://www.e-cigarette-forum.com/f...afety-grades-and-pulse-performance-data.7566/
https://www.e-cigarette-forum.com/f...des-picking-a-safe-battery-to-vape-with.7447/
https://www.e-cigarette-forum.com/f...fety-grades-and-pulse-performance-data.7554//
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
This Sanyo is one of the new generation of slightly larger cylindrical cells being brought to the market primarily for automotive use. It is 20mm in diameter and 70mm long, a 20700 battery. Other sizes and designations for similar cells from other manufacturers include 20650 and 21-70.
I am rating this cell at 16A 4000mAh. It runs a few degrees hotter than the HG2 (which is why the Sanyo has a lower rating) but at 10A and 20A continuous down to 3.2V the Sanyo lasts about 25% longer.
There is also a Sanyo 20700A cell which is rated at 3100mAh and about 30A. You'd have the capacity of a VTC6/30Q/HG2 plus a 30A rating for just a small increase in battery size.
Either of these Sanyo's could be a very good choice to 3D print a custom battery sled for. City of Cloud was kind enough to send me a couple of their samples of the 20700B for this testing but no 20700A's were available. I hope to get a couple of the 20700A's soon.
I don't know if any of these larger cells will eventually replace the 18650 but the Sanyo 20700B is hopefully just the first alternative cell that I'll be testing that offers a good current rating and extra capacity over our 18650's for just a small increase in size.
Continuous-Current Test Results
Pulse-Current Test Results
Sanyo 20700B Specifications
Comments
- At 10A continuous it reached 3909mAh. This is good performance for a 4000mAh cell at 10A so I am rating it at 4000mAh.
- At 15A continuous the temperature rose to 74°C. This is just a bit below the average temperature of a cell operating at its continuous discharge rating (CDR). This is an indication that we are operating near its true rating.
- At 20A continuous the temperature rose to 88°C. This is too hot for this current level to be the rating.
- At 25A continuous the temperature rose to 102°C. This much too hot and is above my 100°C safety limit.
- I am setting a CDR of 16A for this cell. While operating any cell near its rated maximum current level causes damage to the cell, I would expect good cycle life from this cell at 16A continuous.
List of Battery Tests | E-Cigarette Forum
https://www.e-cigarette-forum.com/f...afety-grades-and-pulse-performance-data.7566/
https://www.e-cigarette-forum.com/f...des-picking-a-safe-battery-to-vape-with.7447/
https://www.e-cigarette-forum.com/f...fety-grades-and-pulse-performance-data.7554//
