Charging Times: Charging time for the Brill Battery will vary depending on how depleted the battery pack is when you start to charge. The Brill charger is a simple transformer with a stated voltage output of 24V DC at 250 milliamperes (mA) current. Therefore a 2200mAh battery would take roughly 8.5 hours to fully charge if it were fully depleted when charging began. Similarly, a 3000mAh battery would take roughly 12 hours with similar conditions. Leaving the battery pack connected to the charger for a longer period of time won’t necessarily damage the pack if it is under 36-48 hours but they shouldn’t be left connected indefinitely either. Rebuilt batteries are Nickel Metal Hydride.
Full Depleted or Not: The Brill battery does not need to be fully depleted before charging but do keep in mind the charge time will be shorter and therefore should be connected to the charger for a shorter period of time. That being said it is a good idea to fully discharge then charge the Brill battery pack 3-4 times when first purchased. This will help achieve a full capacity for the pack.
On Memory: Nickel Metal Hydride (NiMh) battery packs do not suffer from “memory” effect like NiCd batteries do. Charging a NiMh pack at various stages of discharge will have no long term effect on the packs overall capacity. NiMh battery packs, similar to NiCd, are rated for 500-600 full discharge/charge cycles over their lifetime. In reality the number of cycles is longer since most packs are not fully discharged before being charged again.
Charge Every Two Months When Idle: NiMh packs have a somewhat higher self-discharge rate than NiCd. Therefore it is good practice to charge an idle pack every two months or so. Storing the pack in a cold environment will help slow their discharge too.