If you have a laptop, someone has probably told you something like: "Hey, don't leave it plugged in all the time, that ruins the battery" or "Use it unplugged so the battery lasts longer." It's one of those pieces of advice that are repeated in offices, WhatsApp groups, and even YouTube tutorials. But how true is it? Are you really doing your computer in favor by using it without a charger? The short answer is: it depends, and in many cases, you're doing the exact opposite of what you think. Modern laptops aren't what they used to be. Much of this myth comes from a time when laptops used nickel-based batteries (NiCd or NiMH), which did suffer from something called the "memory effect": if you didn't fully discharge them before recharging, they lost capacity over time. That advice made sense decades ago. The problem is that today, that advice is completely outdated. For more than a decade, laptops have used lithium-ion (Li-ion) batteries, and these operate with a completely different chemistry. With these batteries, the full discharge/charge cycle is neither necessary nor recommended; in fact, it can be counterproductive. Furthermore, modern laptops include a system called a BMS (Battery Management System) that intelligently regulates how the battery is charged. When you reach 100%, the system stops charging and the computer starts working directly from the electrical outlet, without using the battery. So no, leaving your laptop plugged in won't "overcharge" it or make it explode, as some believe.

Does using your laptop without a charger damage it?

Here's the part that surprises many: constantly using your laptop unplugged can actually damage the battery more, not less. Why? Because every time the battery is completely discharged and recharged to 100%, it consumes a charge cycle. Li-ion batteries have a limited number of these cycles (generally between 300 and 500 full cycles) before their capacity starts to noticeably decrease.

What experts recommend today is keeping your battery charge between 20% and 80%. Why those numbers? Because lithium chemistry is more stable within that range:When the battery is above 80%, the lithium ions are compressed against the anode, which puts stress on the cells. And when it drops below 20%, there is greater degradation due to the conversion of lithium into lithium oxide, which damages both the cathode and the anode.

To put it more simply: extremes are the enemies of your battery, both 0% and 100%.

And if you use your laptop unplugged all the time, you'll inevitably experience those extremes much more frequently.

The good news is that many modern laptops already have a battery conservation mode in the BIOS or their power management applications (such as Lenovo Vantage, ASUS Battery Health Charging, or Dell Power Manager), which automatically stops charging when it reaches 80%. If your laptop has this option, activate it without hesitation.

The number one enemy no one mentions: heat

If there's a true villain for your laptop battery, it's heat, not whether it's plugged in or not. High temperatures significantly accelerate the chemical degradation of lithium cells, regardless of how many charge cycles you've done.

This is where the "use it without a charger" argument can have a point, but only indirectly: when the battery is charging, it generates additional heat. So, if you have your laptop plugged in on a surface that blocks ventilation (like a bed or sofa), you're combining the heat from the charger with the heat from the processor, and that can affect the battery's long-term lifespan. The solution, however, isn't to unplug the laptop, but to ensure good ventilation: use it on hard, flat surfaces, and if you work for many hours at a time, consider investing in a cooling pad with fans. Another point worth mentioning: if you're not going to use your laptop for an extended period, it's best to store it with the battery between 50% and 60% charged. Leaving it stored at 0% can lead to a deep discharge from which it sometimes doesn't recover, and leaving it at 100% accelerates degradation due to voltage stress.

Tips to protect your laptop battery

To summarize everything in concrete tips:

Technology evolves, and our habits should too. Unplugging your laptop constantly not only doesn't help, but it can also be shortening your battery's lifespan without you realizing it. The smartest thing to do is let your computer's power management system do its job and focus on what really matters: temperature and charging range.