Kdest Black 15A 3500mAh 18650 Bench Test Results...just a 10A 3400mAh battery

[Mooch]

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 Kdest is just a rewrapped and overrated 10A 3400mAh cell. At its 15A continuous rating it was almost hot enough to boil water. Its "pulse" rating of 40A is ridiculously high and would bring the voltage down to uselessly low levels. Both of these Kdest cells were identical in performance and appearance to the LG MJ1.

Kdest has printed "MADE IN KDEST" on the metal can which is interesting considering that this is a rewrapped LG cell.

The 18650 ratings table has been updated to include this cell. The two cells were purchased directly from Kdest (Kdest) for the purposes of testing.


Continuous-Current Test Results



Pulse-Current Test Results
Pulse testing was not done as this is a rewrapped MJ1. The test results for that cell are here: LG MJ1 10A 3400mAh 18650 Bench Retest Results...an good 10A battery


Comments

• At 5A continuous it reached about 3100mAh. This is average performance for a high internal resistance 3400mAh cell at 5A so I am rating it at 3400mAh.
• At 10A continuous the temperature rose to 69°C. This is a few degrees below the average temperature of a cell operating at its continuous discharge rating (CDR). This is an indication that we might be operating a bit below its true rating.
• At 15A continuous, the battery's rating, the temperature rose to 96°C. This is way above the average temperature of a cell operating at its CDR and is an indication that we are operating at way above its true rating. The voltage sag is huge and is an indication that 10A or so it its true rating.
• At 20A continuous, it was essentially useless.
• I am setting a CDR of 10A for this cell. While operating any cell near its rated maximum current level causes damage, I would expect ok cycle life at 10A continuous.

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
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//

 

[opticruby]

I looks to me like Kdest are even worse than Efest.

Thanks for testing, @Mooch.

 

[AtmizrOpin]

"made in kdest" LOL! sad thing is, people who don't know about shady, over-seas battery re-wrappers will buy these. it never ends Mooch. thanks for keeping us on the straight and narrow!