This is 1S 18650 Li-ion Lithium Battery BMS Charger Protection Board for 3.7V Battery.

Protections:

Short circuit protection

Overcharge protection

Over-discharge protection

Over-current protection

Pins description:

P-: negative of input or output power

P+: positive of input or output power

B-: negative of the battery

B+: positive of the battery

Features : 

• High accuracy voltage detection circuit;
• Using high voltage device charging terminal;
• The built-in three-stage overcurrent detection circuit (overcurrent 1, overcurrent 2, load short circuit);
• The battery charge and discharge can control the MOS transistor;