Lithium Ion Battery 3.7V - 18650 Cell (2600mAh)
No, these aren’t some sort of weird, AA battery, this is actually a 18650 Lithium Ion Cell. These round high capacity cells have been mainly used in flashlight type applications but with its capability to be used as a drop-in rechargable cell at 3.7V with a capacity of 2600mAh. This is a great battery option for those of you who need a simple to install and replace cell with a lot of juice.
These 18650 Cells have a standard discharge current of 0.2C to a maximum of 1C and can handle about 300 charge cycles.