26650 Rechargeable Battery, 6800mAh High Capacity 3.7v Lithium-ion Rechargeable Batteries for Flashlight Ect

Strike 1: The brand of battery advertised was “CBJJ”. The brand that was delivered was “GTL”. (See photo) I'm guessing that the seller considers them “generic”, but there is a considerable difference between brands in lithium batteries. Strike 2: The batteries are claimed to have protection against over-discharge, but I've found that they do not. They allowed discharge down to 2.5 volts and below, going past the safe discharge level. Strike 3: As received, one cell was almost fully charged at 3.8v or so. The other was almost fully discharged at 2.8v. I suspect that this one has a lot of internal leakage, making it difficult to use in a 2-cell pack, since it will hit its full discharge voltage first, and given the lack of protection, make the pair unreliable. Strike 4: The stated capacity is 6800mAH, but the measured capacity was a little less than 2500mAH. (See photo). It's only 50% more than a set of 18500 cells that I have, rated at 1600mAH, and actually deliver exactly that much. I'll look for another brand of battery and won't buy these again.