ESYB Green 20A 3000mAh 18650 Bench Test Results...tested as 19A/2900mAh, seems to be HG2

[Mooch]

These cells were donated by ESYB for the purposes of testing. 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 ESYB cell appears to be a LG HG2. It looks identical to an HG2 and performs just a bit below, and a bit hotter, than the other HG2's I've tested. This is why I have rated it at 19A/2900mAh. This is very close to the claimed 20A/3000mAh rating though. This cell still has the useless "pulse" rating in large lettering on the wrap but does list both the continuous and pulse current ratings, a very welcome change that's been appearing lately.


Continuous-Current Test Results



Pulsed-Current Test Results



Comments

• At 10A continuous it reached a bit more than 2700mAh. This is too low for a 3000mAh cell at 10A so I am rating this cell at 2900mAh.
• At 15A continuous the temperature rose to 71°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 87°C. This is a few degrees above the average temperature of a cell running at its CDR and is an indication that we are just past the cell's true rating.
• At 25A continuous the temperature rose to 102°C. This is a ridiculously high temperature and is above my 100°C safety limit.
• I am setting a CDR of 19A for this cell. Operating at that level would bring the temperature up to the average for a LG cell operating at its CDR (about 83°C). While operating any cell near its rated maximum current level causes damage, I would expect decent cycle life from this cell at 19A 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

 

[sonicbomb]

An under-performing HG2 under the wrap, hmm I wonder what's the history of those?

 

[Agent47]

An under-performing HG2 under the wrap, hmm I wonder what's the history of those?

These are most likely grade B and C batteries from LG that failed quality control test and are sold to E.SYB and they re-wrap them.

 

[sonicbomb]

I forgot to add these
<sarcasm></sarcasm>

 

[Assi]

As far as I know, Cells manufacturer like LG don´t sell batteries that are not A-grade into the market. I saw in Germany some batteries (from different manufacturer) with rust on them behind the shrink. In all cases that were older batteries, that have most probably changed some Hands in China and were Held (apperantly) not in good conditions for Li-Ion-Cells (too high moisture etc.)