Lithium battery charger and lithium battery charging control method

The invention discloses a lithium battery charger and a lithium battery charging control method. The lithium battery charger comprises a charging chip, a knob switch, a key switch and a first resistor. The lithium battery charger is configured with a first contact and a second contact, the first contact is electrically connected with the power supply end of the charging chip. The second contact iselectrically connected with the chip selection end of the charging chip through the first resistor, the chip selection end is further grounded through the key switch, the knob switch is provided witha third contact and a fourth contact, the knob switch is used for connection or disconnection between the first contact and the second contact, and the charging chip is configured to determine the cut-off voltage during charging according to the connection state of the first contact and the second contact. According to the lithium battery charger provided by the invention, the lithium battery canbe conveniently charged to