Panasonic 14.4v 4.2ah Li-ion Battery.
For highest performance: A new level of battery capacity.
A range of features ensure Panasonic battery packs are tough and long-lasting.Individual monitoring of battery cell voltage.
Each 3.6v segment monitored by sensor to ensure optimal discharge control, preventing both overcharging and overdischarging.Overcharge prevention sensor.
A sensor works to prevent overdischarging (discharge of the battery until voltage falls below a minimum threshold), a disadvantage inherent with Li-Ion cells.Battery Overheat Protection Sensor (OPS)
A temperature sensor cuts off power to the motor before the battery temperature rises to a harmful level and flashes a warning lamp on the tool's control panel to notify the user.