Note: These batteries are designed for DIY purposes and are not recommended to use in industrial applications.
This is a rechargeable Li-ion battery from Power Bee with a nominal output voltage of 3.7V and a capacity of 1100mAh. With around 500 charge cycles and an output voltage of 3.7V these cells pack in high power density in a small AA cell form factor.
Note: This is NOT an AA type of battery, this is specifically a 14500 Li-ion rechargeable battery with a nominal voltage of 3.7V. But it can fit into an AA-size battery holder. Do NOT attempt to replace an AA-type battery with it.