How long is the battery life?

    The life of a rechargeable battery operating under normal conditions is generally between 500 to 800 charge-discharge cycles. This translates into one and a half to three years of battery life for the average user. As your rechargeable battery begins to die, you will notice a decline in the run time of the battery. When your four-hour battery is only supplying you with two-hour's worth of use, it's time for a new battery.