PANASONIC EY9L41B31 p 144V 31 Ah Li LON p BATTERY PACK p Battery pack suitable for use with 144V Lithium Ion Panasonic cordless power tools &65279 Large Capacity The internal structure of the battery was newly designed to increased internal volume & space for storing energy materials High Density By increasing the dimensional accuracy of electrode plates within the battery cell the plate density of the cell & the volume of energy material stored in plate were increased ADVANCED COBALT&8200LIION&8200BATTERY High Output MORE&8200RUN&8200TIMEHigh electrical efficiency lets &lsquo Cobalt&39 Li Ion batteries deliver greater output than &lsquo Manganese&39 Li Ion batteries Low Heat LONG&8200LIFE&lsquo Cobalt&39 Li Ion batteries are less prone to increase in temperature than &lsquo Manganese&39 Li Ion batteries Panasonic Solid Solution PSS&8200 Technology This proprietary Panasonic technology for dissolving & hardening key battery component substances such as cobalt & nickel delivers dramatically enhanced safety exceptional reliability & high output unique to cobalt chemistry Overcharge Prevention Sensor A sensor works to prevent over discharging discharge of the battery until voltage falls below a minimum threshold a disadvantage inherent to lithium ion cells Battery Overheat Protection Sensor A temperature sensor cuts off power to the motor before the battery temperature rises to a harmful level & flashes a warning lamp on the tool&39s control panel to notify the user Individual Monitoring of Battery Cells Individual battery cells are independently monitored to ensure optimal discharge control preventing both overcharging & over discharging Specification 144 Volts 31 Amp Hour capacity 50 minute full 35 minute usable charge times