The examinations below merely indicate the approximate ratings for these 20700 batteries I tested. Any battery that is not an authentic Samsung, Sony, LG, Panasonic, or Sanyo has the potential to alter unpredictably! This is one of the risks associated with using “rewrapped” batteries from other manufacturers, so it is crucial to research any battery you are contemplating purchasing thoroughly.
Improperly utilizing or mishandling lithium-ion batteries can present a SIGNIFICANT DANGER of personal harm or property damage. They are not intended for use outside of a protected battery pack. Never surpass the battery’s current rating; ensure that the plastic wrap and top insulating ring remain impeccable.
Conducting tests on batteries at their limits is hazardous. Under any circumstances, it should never be attempted by individuals who have not extensively studied the associated hazards, comprehended the risks involved, possess the appropriate equipment, and take all necessary safety precautions.
If the battery displays only one current rating figure or solely states “max,” then it must be assumed that it is rated at that current level for any discharge type, including continuous.
Efest 21700 10A In Conclusion
Even though Efest has slightly overstated this cell’s capacity, it performs well like the Efest 18650 2600mAh, surpassing the 10A Samsung 48G and 15A Sanyo NCR20700B in terms of total vaping time at low power levels, below 7A/20W. It is a rebranded version of the LG M50 cell.
The cells I evaluated provided 4900mAh and 4957mAh at 1.0A (0.2C) until reaching 2.5V. Neither cell achieved its 5000mAh rating. Each cell should easily surpass the specified capacity since it represents the minimum guaranteed value and should not be considered the maximum achievable capacity, even if you are fortunate.
LG rates the M50 with a minimum of 4849mAh and a typical capacity range of 5014mAh; therefore, this Efest battery still meets LG’s specifications.
The ratings of this Efest battery are 7.3A and 4900mAh.
Brad’s Vapor generously provided two cells for testing purposes. Many thanks!
Performance Specifications
DC Internal Resistance = average of 34.2mOhms (milliohms) for the two cells.
Total energy delivered down to 3.2V at 5A continuous = average of 13.4Wh (Watt-hours)
Total energy delivered down to 3.2V at 10A continuous = average of 10.5Wh (Watt-hours)
