Will leaving you phone charged overnight cause problems with the battery?
Will leaving you phone charged overnight cause problems with the battery?I was getting a new cell phone with a non-removable battery and the rep warned me to not leave my phone charging overnight because my battery would bloat and wind up not working properly. Does that olden day warning that applies to old technology and nickel-based batteries still apply to today’s technology?
The experts lead me to believe not.
With today’s technology, circuitry now stops the phone from charging once it reaches 100%. The goes through a charge and discharge cycles to keep the battery at 100%. Basically, the charge reaches 100% cuts off and trickles down slowly as topping off a battery can damage it. According to Battery University, “the time at which the battery stays at 4.20/cell (maximum charge) should be as short as possible. Prolonged high voltage promotes corrosion, especially at elevated temperatures” (1). A smartphone knows and prevents this.
A writer at Bryong.com did a test using an app called CurrentWidget on his droid incredible. Once the phone was completely charged, the wall current was cut. The phone, even though in the charger was using battery power. At about hour 2 the phone starts receiving external current again (2). If your phone has a lot of apps running in the background a phone can use wall current as its primary source leaving the battery unused (4).
The safety of leaving the phone charged overnight was also corroborated by ShaneBroesky, co-founder of Farbe Technik who states “Leaving your phone plugged in overnight is okay to do, it will not drastically harm your device,” “Your phone is very smart. Once it’s fully charged, it knows when to stop the current from coming in to protect your phone from overcharging” (3). The only issue with lithium oil batteries is overheating, so remember to remove the case while charging (3). This all can be corroborated by these tech sites here (4) and here (5)
A side note for optimal battery life.
“The sweet spot for lithium-ion batteries is to keep them charged between 50 and 80 percent. This allows for the charged ions to continue to work and protect the life of your battery,” says Shane. “Charging your device in short spurts throughout the day will give these ions just enough energy to keep them going” (3). By keeping it at that range it will keep the voltage within the battery on a less stress state. So charging your device frequently rather than a drain and full charge will get the most out of your battery.
So there you have it, keeping a phone in the charger overnight is not an issue. If you would like to go into greater depth about batteries, I recommended reading the entire articles sourced below, commenting/emailing the source below or speaking with a physics or battery expert. I saw a lot of back and forth (heated debate) between very knowledgeable people as to the reasons, however, the conclusion stayed true.
Question for the experts:
I know I am nitpicking but I could not get a definite answer from my readings and asking two physicists. All lithium ion batteries have a finite number of charge cycles. A charge cycle happens when you use all of the battery’s power not necessarily at once. If I am at work or at home using my phone is it better to keep my phone in the charger (use fewer charge cycles) or keeping the battery in the 50 to 80 optimal percentage range ( partial charge disconnect and recharge as needed)?
(1) (2016). com. Retrieved 17 September 2016, from http://batteryuniversity.com/learn/archive/
(2) Your Smartphone is Lying to You. (2016).Byrong.com. Retrieved 17 September 2016, from http://byrong.com/PowerTesting/
(3) Hill, S. (2015). Should you leave your smartphone plugged into the charger overnight? We asked an expert. Digital Trends. Retrieved 17 September 2016, from http://www.digitaltrends.com/mobile/expert-advice-on-how-to-avoid-destroying-your-phones-battery/
(4) Should I leave my phone plugged in overnight?. (2016). Android Authority. Retrieved 17 September 2016, from http://www.androidauthority.com/leave-phone-plugged-overnight-703078/
(5) Could Overcharging Be Causing Your Battery to Swell? – uBreakiFix Blog. (2016). Ubreakifix.com. Retrieved 17 September 2016, from https://www.ubreakifix.com/blog/could-overcharging-be-causing-your-battery-to-swell/