The costs of running this huge site are paid for by ads. Please consider registering and becoming a Supporting Member for an ad-free experience. Thanks, ECF team.

Cloud King 40A 3000mAh 18650 Bench Test Results...only a 20A 2500-2600mAh battery

Discussion in 'Batteries and Chargers' started by Mooch, Jan 29, 2016.

Thread Status:
Not open for further replies.
Image has been removed.
URL has been removed.
Email address has been removed.
Media has been removed.
  1. Mooch

    Mooch Electron Wrangler Verified Member ECF Veteran

    Supporting member
    May 13, 2015
    Tested at 10A-40A constant current and 30A-50A pulsed. These cells were purchased by me for the purposes of testing thanks to the wonderful donations from so many of you. Thank you! To prevent any confusion with the eGo-type "batteries", I use the term "cell" here to refer to a single 18650, 26650, etc.

    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. My safety precautions are the ones I have elected to take and you should not assume they will protect you if you attempt to do any testing. Do the research and create your own testing methods and safety precautions.

    image.jpg image.jpg image.jpg image.jpg

    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 continuous. Otherwise they would have listed the current rating with two numbers as other companies have done. Or they would have labeled the rating on the wrap as "pulse" or "burst". Battery buyers should not have to hunt down what the number on the wrap means. I will be testing batteries at the rating listed on the wrap and pointing out when they fail to meet that listed rating.

    Bottom Line
    In my opinion this is an average 20A 2500mAh-2600mAh battery with a wildly exaggerated 40A rating. At 20A down to 3.2V it delivers a bit less capacity than a Samsung 25R and about 15% less than an LG HG2.

    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, the battery if there is a malfunction or accidental pressing of your mechanical mod's button.
    image.jpg image.jpg

    • At 10A it reached 2340mAh. This is good performance for a 2500mAh-rated cell, and average for a 2600mAh cell, at 10A.
    • At 15A the temperature rose to 68°C. This is below the average for a cell operating at its CDR and indicates we're still below its rated current level.
    • At 20A the temperature rose to 78°C. This is the average for a cell operating at its CDR and indicates that we're probably running it at its rating.
    • At 25A the temperature rose to 90°C. This is way above the upper limit for a cell operating at its CDR.
    • Discharges at 30A and 35A were not done since they would have exceeded my 100°C safety limit.
    • A discharge at 40A shows the voltage quickly collapsing down to the 2.8V cutoff, rising to an incredibly high temperature of 107°C. This is clearly not a 40A cell.
    • I am setting a CDR of 20A for this cell since its operating temperature is at the average for a cell operating at its CDR. While operating any cell near its rated maximum current causes damage to the cell, I would expect decent cycle life from this cell at 20A.
    • 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

    18650 Safety Grades -- Picking a Safe Battery to Vape With | E-Cigarette Forum

    26650 Safety Grades and Pulse Performance Data | E-Cigarette Forum
    • Like Like x 5
  2. KenD

    KenD Vaping Master ECF Veteran

    Aug 20, 2013
    Stockholm, Sweden
    The name "Cloud King" kinda says it all.

    Sent from my M7_PLUS using Tapatalk
    • Like Like x 2
Thread Status:
Not open for further replies.

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice