These tests below only note the ESTIMATED ratings for these batteries at the time I tested them. Any battery that is not a genuine Samsung, Sony, Murata, LG, Panasonic, Molicel, or Sanyo can change at any time! This is one of the hazards of using “rewrapped” or batteries from other manufacturers so carefully research any battery you are considering using before purchasing.
Misusing or mishandling lithium-ion batteries can pose a SERIOUS RISK of personal injury or property damage. They are not meant to be used outside of a protected battery pack. Never exceed the battery’s current rating and keep the plastic wrap and top insulating ring in perfect condition.
Testing batteries at their limits is dangerous and should never, ever, be attempted by anyone who has not thoroughly studied the dangers involved, understands the risks, has the proper equipment, and takes all appropriate safety precautions.
If the battery has only one current rating number, or if it only says "max", then I have to assume the battery is rated at that current level for any type of discharge, including continuous.
Bottom Line
This is an accurately rated, good performing ultra-high capacity 21700 cell. It is identical in appearance, performance, and operating temperature to the Samsung 50E but Efan strongly denies that is it a rewrapped 50E. They say it is a cell made by them.
The Efan datasheet lists the minimum capacity at 4780mAh and nominal capacity at 5000mAh. The four Eizfan’s I tested delivered 5006mAh-5010mAh at 1A (0.2C) down to 2.5V. This is astounding consistency and they all easily meet their minimum capacity rating. This consistency is typical of good OEM cells from Samsung, Sony, LG, etc., but is better than any China manufactured cell I have seen so far.
This Eizfan outperforms the Samsung 48G but I have not tested the LG M50 yet so I can’t compare them.
There is a “15A” number on the wrap and the datasheet claims a “Max short time discharging current” rating of 15A but the time is not listed and the criteria used to set the rating are unknown. Therefore it is a useless rating.
I am rating this Eizfan at 10A/30W and 5000mAh. I will be retesting these again at some point to confirm they have not changed what cell they are wrapping.
Four cells were donated for the purposes of testing by Efan (Shenzhen Yi Fang Technology Co., Ltd. - IMR Battery, Li-Ion Battery). Thank you!
Continuous Current Discharge Graphs
Ratings Graphic
Performance Specs
- DC Internal Resistance = 31.0mOhms (milliohms) average for four cells.
- Total energy delivered down to 3.2V at 5A continuous = 13.2Wh
- Total energy delivered down to 3.2V at 10A continuous = 10.6Wh
I want to work for the vaping community full time! If you feel what I do is worth a couple dollars a month and you would like early access to battery availability and testing news and a say in what I test then please consider becoming a patron and supporting my testing efforts: Battery Mooch is creating battery tests and educating vapers | Patreon.
Efan paid a fee to be moved to the front of the testing queue, which currently has a 10-12 week backlog. This cannot influence my test results as this is science, not a subjective review. In addition, they pay in advance, have no say about what is in this report, and I don’t care if any company never does this or donates batteries again. My reputation is a lot more important than any battery donation or fee to be moved to the front of the queue.
To see how other cells have tested check out this link: List of Battery Tests | E-Cigarette Forum
Misusing or mishandling lithium-ion batteries can pose a SERIOUS RISK of personal injury or property damage. They are not meant to be used outside of a protected battery pack. Never exceed the battery’s current rating and keep the plastic wrap and top insulating ring in perfect condition.
Testing batteries at their limits is dangerous and should never, ever, be attempted by anyone who has not thoroughly studied the dangers involved, understands the risks, has the proper equipment, and takes all appropriate safety precautions.
If the battery has only one current rating number, or if it only says "max", then I have to assume the battery is rated at that current level for any type of discharge, including continuous.
Bottom Line
This is an accurately rated, good performing ultra-high capacity 21700 cell. It is identical in appearance, performance, and operating temperature to the Samsung 50E but Efan strongly denies that is it a rewrapped 50E. They say it is a cell made by them.
The Efan datasheet lists the minimum capacity at 4780mAh and nominal capacity at 5000mAh. The four Eizfan’s I tested delivered 5006mAh-5010mAh at 1A (0.2C) down to 2.5V. This is astounding consistency and they all easily meet their minimum capacity rating. This consistency is typical of good OEM cells from Samsung, Sony, LG, etc., but is better than any China manufactured cell I have seen so far.
This Eizfan outperforms the Samsung 48G but I have not tested the LG M50 yet so I can’t compare them.
There is a “15A” number on the wrap and the datasheet claims a “Max short time discharging current” rating of 15A but the time is not listed and the criteria used to set the rating are unknown. Therefore it is a useless rating.
I am rating this Eizfan at 10A/30W and 5000mAh. I will be retesting these again at some point to confirm they have not changed what cell they are wrapping.
Four cells were donated for the purposes of testing by Efan (Shenzhen Yi Fang Technology Co., Ltd. - IMR Battery, Li-Ion Battery). Thank you!
Continuous Current Discharge Graphs
Ratings Graphic
Performance Specs
- DC Internal Resistance = 31.0mOhms (milliohms) average for four cells.
- Total energy delivered down to 3.2V at 5A continuous = 13.2Wh
- Total energy delivered down to 3.2V at 10A continuous = 10.6Wh
I want to work for the vaping community full time! If you feel what I do is worth a couple dollars a month and you would like early access to battery availability and testing news and a say in what I test then please consider becoming a patron and supporting my testing efforts: Battery Mooch is creating battery tests and educating vapers | Patreon.
Efan paid a fee to be moved to the front of the testing queue, which currently has a 10-12 week backlog. This cannot influence my test results as this is science, not a subjective review. In addition, they pay in advance, have no say about what is in this report, and I don’t care if any company never does this or donates batteries again. My reputation is a lot more important than any battery donation or fee to be moved to the front of the queue.
To see how other cells have tested check out this link: List of Battery Tests | E-Cigarette Forum
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