The Conservation Model will allow the battery to charge only to 55-60% which can substantially increase the longevity of the battery, under some circumstances. To enable the Conservation Mode go to Lenovo Settings and navigate to Home > Power > Conservation Mode.
If you keep your computer connected to the power supply most of the time, the battery would normally always stay at 100%. However, keeping your battery fully charged for longer periods can decrease its longevity faster compared to when it is moderately discharged.
A fully a charged battery has the highest voltage which increase its aging related stress. As the battery discharges its voltages gradually falls which reduces the stress. When the battery is discharged to 40% to 60%, there are no additional benefits of discharging further.