Keep your laptop charged all the time or use the battery?

A fairly common question about using laptops is how to extend battery life (or at least how to avoid shortening more than normal). While all batteries deteriorate over time, many users question whether the use we give them can influence – albeit slightly – their ability to retain energy and power our devices for longer.

If so, then how should we use batteries?

In other words that is, Do we have to keep them 100% charged all the time or do we have to turn them on and off according to their energy level?

Several experts he spoke to BBC World recommend what is the best way to spend the batteries, which are mostly made of lithium (either lithium ions or lithium polymers).

Battery life

“Battery technology is getting better and better with each generation. 10 years ago, laptop battery efficiency began to degrade after a couple of hundred charge cycles,” says Ashley Rolfe, head of Lenovo Technology in Ireland and the United Kingdom, on BBC World.

See laptop batteries typically have a lifespan of three to five years, during which they can complete between 500 and 1,000 charge cycles.

“One wants the battery to give it as much energy as possible for each charge and to last three to five years,” Kent Griffith, a researcher in energy technology at Northwestern University, USA, told BBC World

How to achieve this balance?

Leaving a laptop plugged in and 100% all the time “is absolutely safe and perfectly normal,” says Rolfe from Lenovo, BBC World.

Lenovo and other brands of laptops “use sensors and control logic to ensure the battery doesn’t overcharge or overheat,” he explains.

However, “keeping a battery at 100% all the time will slightly reduce its lifespan.”

His colleague Phil Jakes, director of Strategic Technology and chief engineer at Lenovo, agrees with him: “With the higher energy density chemistry adopted in recent years, we have found that batteries degrade much faster if they are they keep fully charged, especially at higher temperatures, “he tells BBC World.

The reason is that “100% charging is the heaviest condition your battery can be in because that’s when the voltage is highest,” explains Kent Griffith of Northwestern University.

The manufacturer HP is of the same opinion, as it tells BBC World: “HP does not recommend leaving laptops connected to AC power at all times.”

“Most current batteries have the technology to prevent overcharging once they reach 100%,” but this technology does not prevent the high charge state “creating an additional voltage in the battery that can accelerate its degradation with time, ”HP explains.

So “if you keep the battery away from 100%, the battery can last longer, no doubt,” Griffith says.

The recommendation of these experts is to limit the amount of time the laptop stays fully charged or instead of charging it to 100%, charge it only up to 80% each time you plug it in.

“Technically, batteries are happier at 50% charge, while being under higher voltage at 0% or 100%, so technicians say it’s best to keep them between 20 and 80%“, Says Rolfe.

While limiting the load to 80% “provides the maximum benefit, there is still a significant benefit to reducing the maximum load point to 90 or 95%,” says Jakes.

Microsoft also warns on its website that in the case of its Surface laptops (not for other brands) “batteries kept on high charge will lose capacity faster.”

“You can help prevent this accelerated deterioration by not leaving your laptop (Surface) plugged in for extended periods of time. If you need to keep your laptop plugged in continuously, we recommend using the battery charge limit mode,” says Microsoft.

Several brands, such as Microsoft, Lenovo and HP offer the option to limit the maximum amount of laptop charge in their configurations.

For example, HP allows you to limit it to 80% in “Maximize my battery health” mode.

In general, “if you want the battery to last longer, you could make each cycle give you a little less power (80% instead of 100%), but that way the battery could complete more charge cycles,” Griffith says.

That is, it’s about making “a balance between how much charging time the battery gives you each time it charges versus how many cycles it can complete” over its entire life, he continues.

How are you going to use the laptop?

But these recommendations don’t necessarily mean you have to worry about unplugging your laptop immediately every time it reaches 100%.

“All laptops have control circuits to protect the batteries and prevent overcharging. But you can increase the battery life by leaving them at 80%,” says Rolfe, from Lenovo.

But at the same time, he clarifies that “batteries last so long these days that it’s probably not worth worrying for most users.”

Today, “batteries are so good that they usually last longer than the life of the laptop,” he says.

Rolfe’s final recommendation is to think about how you will use the laptop. That is, evaluate if you are going to have constant access to a plug or if you are not going to be able to connect to the power for a good while. In the latter case, it would be better to take it with the full load.

“If you’re at your desk most of the time, set a upload limit,” he says. “But if you’re on the move most of the time, leave it at 100% and don’t worry about it!”

See also:

How to disinfect mobile phones, computers and other electronic devices? (+ Video)

In video, tips to increase battery life

(Pres BBC News)