How long should you charge a new laptop before using it for the first time?

You’ve probably heard that new laptops need to be fully charged before use. Some even say you should drain the battery and then recharge it. This initial break-in phase is believed to help calibrate the battery so that its true capacity sets in. The aim is to avoid the memory effect, where partial discharge cycles lead to the permanent loss of battery capacity due to the unused portion of its electrode material crystallizing over time. In this sense, the battery “forgets” the unused capacity. It usually takes about two to three hours to fully charge a laptop, but others say you should leave it plugged in for about 12 to 24 hours before first use.

The two types of batteries known to develop the memory effect are nickel-cadmium (NiCd) and nickel-metal hydride (NiMH) batteries. Sometimes these batteries may need three to five complete charge and discharge cycles to start working properly. However, modern laptops use lithium-ion (Li-ion) or lithium-polymer (LiPo) batteries, which do not have such a memory effect. So you don’t need to leave your laptop plugged in for a while before using it: these batteries don’t need to be broken in.

That said, it is recommended to plug in the laptop when you use it for the first time. You don’t want the battery to drain while setting it up. Li-ion and LiPo batteries self-discharge at a rate of one to three percent per month. So if the laptop sits on a shelf for too long, the battery charge may be low.

Setting up a laptop can be a complex process if you want to configure everything to your liking and get the most out of your new computer. However, for a ready-to-use experience, it can take less than 30 minutes. Basic setup includes unboxing and configuring the operating system. Windows and Mac have setup wizards that walk you through the process, including creating a Microsoft account or Apple ID (if you don’t already have one). Once you can boot the operating system, you are good to go. You just need to do a few updates, as the operating system and drivers may be outdated, and install the basic software you need (a browser and a few productivity apps).

Where it starts to take hours is when you have to transfer data from an old computer during the setup process. This will depend on the amount of data available and the speed of your Internet connection. What can add even more time to the setup process is installing all the software you need and customizing the appearance, security configurations, and performance optimizations. It may also exceed the one hour mark if you intend to configure backup and recovery options. In total, it takes between two and four hours. Of course, if you decide to fully charge the laptop before your first use, you can add that charging time to the overall setup time.

The problem with modern laptops is that they “know” when to stop charging. They have a specialized controller called a battery management system (BMS), which constantly monitors the condition of the battery, including the charge level. When the battery reaches 100%, the charging process is stopped and the laptop’s internal power is switched to the charger. So yes, leaving your laptop plugged in all the time is generally acceptable. The battery will not overcharge, meaning it will not generate excessive heat, which could accelerate the rate of thermal degradation and shorten the life of the device.

However, as it is the nature of batteries to self-discharge when not powered by anything, the BMS will reactivate charging once the battery drops below a certain threshold (usually when it drops below 95%). This is called trickle charging, in which the charger delivers a small amount of current to keep the battery charged. This means you don’t have to worry about your laptop constantly charging.

While it’s generally acceptable to leave your laptop plugged in all the time, it’s also not optimal because it forces the battery to stay at its upper voltage limit for a long time. This is stressful on the battery and can lead to electrochemical changes that degrade its capacity. You should also never completely drain your laptop battery. Although the sweet spot is 50%, you should follow the 80-20 rule for rechargeable batteries.