Busbars 25A 1750mAh 18650 Bench Test Results...accurately rated 25A, fantastic battery!

These cells were donated for the purposes of testing by Cale at Sub Ohm Innovations. 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 Busbar cell is a great performer and is accurately rated at 25A. I gave it an 1800mAh capacity rating, a bit higher than the claimed 1750mAh. It lists both the continuous and pulse ratings on the wrap and is the first cell to also list the pulse length and duty cycle for the pulse rating! This is fantastic and is a great step towards completely open and accurate cell ratings, thank you.

It's supposed to be a "hybrid" chemistry cell (sometimes called INR), but its discharge curves are much more like an ICR cell than other hybrid cells like the 25R and VTC4/5. Like an ICR its voltage holds pretty steady before quickly dropping as the cell approaches empty. I haven't directly compared Busbars against the Tesiyi 40A 2600mAh or Aspire 40A 1800mAh ICR cells but hope to do so soon.


Continuous-Current Test Results



Pulsed-Current Test Results



Comments

• At 10A continuous it reached about 1678mAh. This is above average performance for a 1750mAh cell at 10A so I am rating this cell at 1800mAh.
• At 15A continuous the temperature rose to 63°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 71°C. This is a few degrees below the average temperature of a cell running at its CDR.
• At 25A continuous the temperature rose to 80°C. This is just above the average temperature of a cell running at its CDR and is an indication that this is the cell's true rating.
• At 30A continuous the temperature rose to 88°C. This is above the average temperature of a cell running at its CDR and is an indication that we're above the cell's true rating.
• At 35A continuous the temperature rose to 97°C. This is significantly above the average temperature of a cell running at its CDR. The voltage is noticably sagging and is an additional indication that we're above the cell's true rating.
• I am setting a CDR of 25A for this cell. Operating at that level would bring the temperature up to just above 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 25A 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

 

I would say no as it's much easier to contract out a run of the cell they like. Good question for them though!

 

Yes, the charging for IMR, ICR, and INR is the same and is done at the same voltage...4.20V. There are a few specialized INR batteries that require 4.35V but not the Busbars or the LG's, Samsung 25R and VTC4/VTC5 that are also INR.

IFR requires a 3.6V charger.