Shockli Blue 30A 2400mAh 18650 Bench Test Results...a poor performing 17A battery

[Mooch]

These cells were donated for the purposes of testing by Shockli. 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 is a poor performing cell that I am rating at 17A/2400mAh. While the wrap does list both the continuous and pulse ratings, normally a very good thing, its claimed 30A continuous rating is wildly exaggerated. Its high internal resistance, nearly double that of most good 20A cells, means that it suffers from considerable voltage sag. At 25A continuous it got hot enough to boil water and at its claimed 30A continuous rating its voltage quickly collapsed. Its pulse performance was significantly below that of most 15A-20A cells. Its appearance doesn't match any battery I've tested so far.


Continuous-Current Test Results



Pulsed-Current Test Results



Comments

• At 10A continuous it reached about 2275mAh. This is about average performance for a high internal resistance 2400mAh cell at 10A so I am rating this cell at 2400mAh.
• At 15A continuous the temperature rose to 72°C. This is a few degrees below the average temperature of a cell running at its continuous discharge rating (CDR).
• At 20A continuous the temperature rose to 86°C. This is several degrees above the temperature of a cell running at its CDR and is an indication that we are above the cell's true rating. The voltage sag at this current level is quite large, also indicating that we are above its true rating.
• At 25A continuous the temperature rose to 102°C. This is a ridiculously high temperature and a strong sign that we're way above the cell's true rating. The voltage sag is huge.
• At 30A continuous, the cell's claimed rating, the voltage quickly collapsed.
• I am setting a CDR of 17A for this cell. Operating at that level would bring the temperature up to the average 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 17A 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
18350/18500 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

 

[Assi]

Several Chinese Manufacturerer are in a Position to manufacture High-Drain batteries, but as far as I know up to a capacity of 2.2Ah at around 5C.
The upper side (Plus side) reminded me a bit on Hitachi-Maxcell batteries, but I could not find any battery that would fit the results. Most Hitachi-maxcell batteries are Power-Tool batteries...so most probably it would be a Chinese made one?

 

[sonicbomb]

↑ Whut? That makes no sense at all.

Another terrible rewrap, thanks Mooch.

 

[Assi]

I will try to explain it again ;-) This Chinese dealer buys on the market, what he can get and rewrap the batteries under his own brand. When they can not get batteries from LG, Samsung, Sony etc., they would rewrap other batteries they find.
Mooch wrote:" Its appearance doesn't match any battery I've tested so far." I assume, that he meant, that the upper side of the battery (Plus-side) does not match other manufacturer like LG Chem, SDI etc. - clear?

 

[Mooch]

I will try to explain it again ;-) This Chinese dealer buys on the market, what he can get and rewrap the batteries under his own brand. When they can not get batteries from LG, Samsung, Sony etc., they would rewrap other batteries they find.
Mooch wrote:" Its appearance doesn't match any battery I've tested so far." I assume, that he meant, that the upper side of the battery (Plus-side) does not match other manufacturer like LG Chem, SDI etc. - clear?

The positive contact structure, crimp, and the steel can's surface finish and tooling marks don't match anything I've tested so far. I agree, it is most likely a Chinese-manufactured cell.

 

[sonicbomb]

Understood