How to use and charge the battery to make the smartphone battery last longer

How to use and charge the battery to make the smartphone battery last longer

“When I noticed, my smartphone was going to run out soon…”
“I still don’t want to buy a new smartphone, but my battery is n’t working …”

In fact, it is often the use of smartphone batteries and lithium-ion batteries that cause this.

The background communication of the app, Wifi, Bluetooth operation, etc. are not completely irrelevant, but how to use the battery and how to charge it have a greater impact on the smartphone’s battery life.

In addition, many people believe that the old urban battery (nickel metal hydride battery, etc.) used the wrong urban legend that the battery lasts for 100% after it has been used up. .

(* I will explain in detail later, but if you want to keep your smartphone’s battery lasting, you need to use the opposite way.)

I will explain how to make such a smartphone’s battery last longer, from the perspective of a lithium-ion battery specialist, its principles, how to charge it properly, and how to use your smartphone.

Principle of lithium-ion battery

Before explaining how to use a long-lasting smartphone battery, let’s first briefly explain the principle of the lithium-ion battery in it.

The exact chemical formulas are also listed in the video, so they are omitted. However, the following two chemical reactions proceed during charging.

  •      Lithium ions (Li +) escape from the positive electrode (LiCoO2)
  •      Li + enters the negative electrode (graphite)

The point is that if you remove too much Li + from the positive LiCoO2 (= charge too much), it becomes unstable like Jenga in the second half of the game.

Jenga is just an example, so it is not strict in terms of mechanism, but I think that this principle is easy to follow when considering Jenga’s image.

In addition to charging too much, charging quickly (= pulling out Jenga at high speed) is also prone to instability.

Factors that the battery does not last long

In other words, overcharging (overcharging) is one of the factors that prevents the battery from lasting long.

Old batteries (such as Ni-Cd batteries) have a so-called “memory effect” phenomenon, so it was long-lasting to use them fully until they were fully charged.

However, the lithium-ion battery installed in current smartphones such as the iPhone will not last long if it is used.

In other words, it is better to avoid charging your smartphone battery to 100% if possible.

In principle, there is no specific upper limit, but for example, if the battery reaches 80%, the battery life will vary greatly just by stopping charging.

Also, as explained in the previous principle, if you want to keep your smartphone’s battery lasting, you should avoid charging at high temperatures or rapid charging.

For example, this was published as a presentation material for the 2009 “Environmental Vehicle Dissemination Policy Study Group” in 2009, but it can deteriorate even when it is in use or at high temperatures.

This is an AESC lithium-ion battery installed on the Nissan Leaf, but you may think that it is not much different from what is installed on smartphones such as the iPhone.

Then, if the temperature is low, it is NG that it is too cold. If the temperature is below 0 ° C, lithium metal may accumulate in the lithium-ion battery like frost and shorten the life.

Quick charge is not good either. If you have a smartphone, you don’t have a compatible charger in the first place.

On the other hand, if the battery is left uncharged (nearly 0%), the lithium-ion battery will deteriorate. The so-called “overdischarge” phenomenon occurs.

“Overdischarge” is a phenomenon that occurs when a battery tries to flow current after it has been completely discharged. Even if the current flows, the battery has reacted completely, so what happens is that the other parts react (corrode). Naturally, it leads to deterioration.

5 NG usage of smartphone battery

That’s why these five methods should be avoided as much as possible when using smartphone batteries. If you want to use it at least for a long time.

  •      Charge to 100%. And keep it plugged into the power supply.
  •      Use up to 0%.
  •      Leave it in a hot place.
  •      Use in cold places.
  •      Use while charging.

The fifth use while charging is not a characteristic of the lithium-ion battery, but a systemic problem in general electronic equipment.

If you use it while charging, the circuit becomes busy and heats up. So it gets hot. As a result, the battery life is shortened.

Battery usage Q & A

Q1. “Battery life is determined by the number of charge / discharge cycles, so charging and using it little by little increases the number of charge / discharge cycles. Some people say that it should be charged. How is it actually?

A1. That is a lie. Certainly, if the usage is the same, the life of the battery is determined by the number of charge / discharge cycles, but in reality, the influence of the usage will be significant. It is not simply determined by the number of times it is charged. If you use your smartphone for the same amount of time in total, it will definitely last longer if you use it within the range of 20-80% charge, for example, rather than 0-100%.

Q2. I always leave my smartphone charged when I go to sleep. Naturally, the charge is kept at 100%, but isn’t it good?

A2. Not good. (Although I’m confused when I’m bothersome.) Of course, for recent smartphones, especially iPhones and other devices, charging is automatically stopped even if the charging cord is kept connected, so overcharging. There is no danger of becoming. However, keeping the battery charged at 100% is a factor that does not last long, so I think it is better to stop it if it is not troublesome.

Q.3 I often say things like battery life is not good when background apps, Wifi, or Bluetooth is running, what about it?

A3. There seems to be some, but smartphone software is also being optimized, so it will not drain the battery as much as it used to be. However, you may want to pay attention to the brightness of the display.

Q4. Should I use genuine chargers and batteries?

A4. It seems that you don’t have to worry about it unless the charger is strange. There are no very strange products on the market. Maybe there are things that take a long time to charge, but only to that extent. However, we strongly recommend using only genuine batteries. Lithium-ion batteries made by strange manufacturers in China and South Korea often burn, and otherwise they are like spec scams. I will write more about this issue in another article.