Fully charge new Sony BPS9 battery packs before use.
New pack needs to be fully charged and discharged (cycled)
a few times before it can condition to full capacity.
For laptops that work as Desktop Replacement,
the Toshiba PA3534U-1BAS battery should be re -installed every 3-4 weeks and allowed to fully discharge.
Leaving the Gateway Nv52 battery in a laptop while using an electrical outlet for long periods of time will keep the battery in a constant state of charging up and that will reduce the life cycle of the battery.