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 only says "max" 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.
Cell photos: https://imgur . com/a/WItuD
(Sorry for the split link but direct links to Imgur do not display properly)
Bottom Line
This “40A” cell is overrated by a LOT. IronSmith’s rating is even useless as a “pulse” rating. The first pulse at 40A on a fully charged cell dropped the voltage to under 3.10V.
The 23A 2100mAh VTC4 easily outperforms the IronSmith cell. The VTC4 hits harder and runs for a bit longer.
I do not know what cell IronSmith is using. I thought it might be one of the LG HD Series cells because of its four “leg” top contact and ratings but the metal can and tooling marks don’t match any of the LG HD Series cells I have here. LG might have changed the can or it could be a China-manufactured cell.
IronSmith gave this cell a 7A charge rating. This is higher than the fast charge rate of any 18650 and is guaranteed to shorten the life of your battery. I recommend 2A charging maximum for long cell life.
I am rating this IronSmith at 25A and 2050mAh.
The two cells that were tested were donated for that purpose by IronSmith Group. Thank you!
Continuous-Current Test Results

Comparison to Sony VTC4 Test Results

Pulse-Current Test Results

Ratings

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
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 only says "max" 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.
Cell photos: https://imgur . com/a/WItuD
(Sorry for the split link but direct links to Imgur do not display properly)
Bottom Line
This “40A” cell is overrated by a LOT. IronSmith’s rating is even useless as a “pulse” rating. The first pulse at 40A on a fully charged cell dropped the voltage to under 3.10V.
The 23A 2100mAh VTC4 easily outperforms the IronSmith cell. The VTC4 hits harder and runs for a bit longer.
I do not know what cell IronSmith is using. I thought it might be one of the LG HD Series cells because of its four “leg” top contact and ratings but the metal can and tooling marks don’t match any of the LG HD Series cells I have here. LG might have changed the can or it could be a China-manufactured cell.
IronSmith gave this cell a 7A charge rating. This is higher than the fast charge rate of any 18650 and is guaranteed to shorten the life of your battery. I recommend 2A charging maximum for long cell life.
I am rating this IronSmith at 25A and 2050mAh.
The two cells that were tested were donated for that purpose by IronSmith Group. Thank you!
Continuous-Current Test Results

Comparison to Sony VTC4 Test Results

Pulse-Current Test Results


Ratings

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
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