I generally do not unplug/undock my notebook. Does this hurt the battery?
No, the battery has built in controls which stop the charging process when the battery is full.
All rechargeable batteries wear out with time and usage. As time and cumulative use increase, the performance will degrade. For the typical user, noticeable reduction in run time generally will be observed after 18 to 24 months. For a power user, reduction in run time generally may be experienced prior to 18 months.
https://www.dell.com/support/article/ro/ro/robsdt1/sln128667/laptop-battery-faq?lang=en
The smaller the discharge (low DoD), the longer the battery will last. If at all possible, avoid full discharges and charge the battery more often between uses.
Lithium-ion suffers from stress when exposed to heat
Exposing the battery to high temperature and dwelling in a full state-of-charge for an extended time can be more stressful than cycling.
https://batteryuniversity.com/index.php/learn/article/how_to_prolong_lithium_based_batteries
How to charge lithium-ion batteries
1. Perform shallow discharges.
Discharge it like 30% and charge it 20%
One charge cycle count as 100% of the battery power, for example if you discharge it 40% + 30% + 20% + 10% with charging in between it counts as one cycle.
2. Don’t leave it fully charged and if you do charge it to 100%, don’t leave it plugged in
Use 40%-80% as a guideline.
3. Keep it cool – if possible. A hot battery will degrade in health much faster than a cool one.
Lithium-polymer batteries – applies the same as for lithium ion.
Best way to keep your battery at optimum levels is to use a power bank.
Check how to recondition batteries : click here