It has been a problem concerned by most of computer users for a long time—should I leave my laptop plugged in or on battery power? Unfortunately, this is not a question I can answer you with a single “yes” or “no” as there are many factors affecting the lifespan of a battery from which the types of battery, the ambient conditions you put your laptop and what you use your laptop to do are included.
However, I can give a definitive suggestion is that you should make compromise between the two options. According to expert, let your laptop be 40% to 80% is the optimal choice as this keeps your laptop in the healthiest condition. Read on you will know why is that!
Truth for Battery
There are two types of lithium-based batteries in our daily life—lithium-ion battery and lithium-polymer battery. It’s not an easy task to explain their difference in a short sentence but they function in broadly the same way, with power being created by the movement of electrons.
No matter your devices equipped with Li-ion or Li-polymer battery there are two pieces of truth:
They won’t be overcharged. Unlike traditional batteries, the Lithium-based batteries will cease charging and won’t start again until the voltage falls below a certain level as soon as it hits 100% so that it will not cause damage even though you leave it plugged in all the time.
They will damaged by full discharge. This can be easily explained by the limitation of battery’s discharge and recharge circles. Every battery has a finite number of times it can be charged and discharged. If you frequently fully discharge your battery, it will dead as a doornail someday. Furthermore, having a battery fully discharged for an extended period can put it into a deep discharge state, from which it might never recover.
The higher the charge level is, the shorter the battery’s life will be. Voltage level is an important index to measure the life span of a battery. In the general case, Lithium-ion batteries charge to 4.20V/cell, amounting to 100% of its capacity. The lifespan lies in 300-500 discharge circles, however, every 0.1v/cell drop below 4.2v/cell doubles the circle but hold less capacity. And raising the voltage above the 4.2v/cell would shorten the life.
High temperature cause irreparable damage. There is a rule of thumb for preventing battery from damaged that is avoid overcharging and overheating. Since overcharging won’t happen, overheating should be carefully monitored. Usually, the 30 degree Celsius is the maximum temperature that your battery could bear. Attention should be paid is that not only environmental conditions heat up your laptop, gaming or long time working do the same.
Since this is not a problem for those who often use laptop for travelling as they will use battery power on their way and AC at home. But if you only use your laptop at home you’d better balance the two ways. And undoubtedly, to prolong your battery life, you should carefully monitor the heat and don’t full discharge it.