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Redmi 7/7A

[Discussion] [How it Works #7] What is the battery in your phone or smartphone?

2019-05-27 01:29:18
2371 109

Dear Mi Fans!

This is a new series about all parts your smartphones and how it works on device!
Almost all modern smartphones are equipped with Battery. But not all of you know how it work! Today you'll know more about this smartphone detail.

What is the battery in your phone or smartphone !!??
What is the battery in the phone no one really thinks. Meanwhile, thanks to this invention, the phone can rightly be considered "mobile". There is no need to constantly sit at the electrical outlet, or throw away fabulous money for an endless replacement of standard batteries.
An electric current battery is an energy storage device, its principle of operation is achieved due to the reversibility of internal chemical processes. These processes ensure its multiple “charge-discharge”. In other words, it is an autonomous power supply for all kinds of electrical devices, incl. for phones, smartphones and tablets. The battery is obtained by combining several batteries into a single electrical circuit.

The battery needs to be recharged periodically in order to replenish the level of chemical energy that is gradually being consumed. The level of consumption depends on many factors, both external and internal. You can charge this battery not only from a classic power socket. You can use any alternative sources of constant limited current with a voltage that is higher than the voltage in the battery itself. Which gives the possibility to charge “less” with “more”.

Let's see what is the Battery in mobile phone.

Battery in the device: what was before?
The very first rechargeable batteries were nickel-cadmium (Ni-Cd) or nickel-manganese (Ni-Mh) and small containers, up to 500 mAh. Batteries often failed, could swell, flow and even explode if the battery was old or when charging was given a greatly increased voltage. Such batteries were installed in many push-button monoblocks and clamshells. Remember, some batteries in the phones even consisted of several, assembled in one unit, round batteries? This type of battery for phones had a memory effect.

The memory effect was that at the time of the reboot, the battery could show its own, personal, incomprehensible to anyone, the percentage of charge remaining. It also happened that the phone needs to be put on charge, restart it, and the battery shows more than half the charge. Nickel-cadmium rechargeable batteries gradually, with each charge-discharge cycle, lost their capacity due to the loss of ions that store the charge.

Battery in the gadget: what now?
Modern batteries are devoid of all the above disadvantages. They do not explode, rarely swell, do not lose capacity over time, do not have a bad memory effect. The only problem is the low battery capacity for modern smartphones. For example, for a dual-purpose smartphone, with 3G, GPS and a screen of 5 inches, a 1500 mAh battery is enough for a maximum of a working day. Few manufacturers produce a range of smartphones, in which the emphasis is placed on a large battery capacity. Many forums are full of holivar about whether a charge-discharge cycle is needed to bring the battery to life and use it to its maximum capacity. Probably not necessary. So calmer!

Battery in the device: what's in the future?
Explore forums, scientific articles. Already there are pilot scientific developments for the production of environmentally friendly batteries from sugar, rhubarb and from radioactive metals. What will happen next - we can only guess. What is the battery in the device? This is an energy storage device for surfing the Internet, reading books, watching movies and other tasks.

Year by year, the batteries in smartphones are becoming more sophisticated: their capacity increases, their weight and size decrease, and the drawbacks disappear. Do not forget about environmental safety, because this detail is considered the most "dirty" in modern gadgets. Let's see what kind of "batteries" can be found today in mobile devices.

Throughout the history of cell phone development, they used four types of batteries:
  • nickel-cadmium;
  • nickel metal hydride;
  • lithium ion;
  • lithium polymer.

To date, in the arsenal of developers, the last two types remain as the most technologically advanced, efficient and “clean”. These types of batteries can be found in the descriptions of most smartphones.

Ni-Cd batteries.
This type of power source has come from the domobil era. The first samples are known from the end of the XIX century. Until the end of the last century, industrialists made numerous attempts to get rid of their inherent flaws, and to some extent they succeeded. Anyway, there was simply no particular choice for the developers of the first mobile devices.

The main claims were as follows:
  • the use of toxic metals harmful to human health in the construction;
  • insufficient battery capacity;
  • limited number of charge / discharge cycles;
  • low manufacturability in production, leading to an increase in cost;
  • the so-called "memory effect".

The latter was that when charging is not fully discharged battery, its capacity decreased by a certain amount. As a result, before the first use, the battery had to be driven through a full charge-discharge cycle several times. There were and pluses at such power sources- a wide range of operating temperatures.  Nevertheless, there were significantly more minuses, and when trying to cope with them, the following type of battery was created.

Ni-MH batteries.

They lacked toxic cadmium, at the mere mention of which hysteria occurs with particularly impressionable defenders of nature. In addition, the memory effect was much weaker. The capacity has also increased, and the cost, on the contrary, has slightly decreased.

But there were serious drawbacks compared to NiCd batteries:
  • the need to use a complex charger;
  • reducing the number of charge / discharge cycles.

Both types of batteries were subject to a sufficiently high degree of self-discharge, which seriously limited the autonomy of mobile devices based on them. And when the next generation appeared on the horizon, the designers with a joyous squeal threw them into the dustbin of history.

Lithium-ion batteries.

This type of battery caused a real revolution in the world of gadgets. From now on, the duration of their work in the standby mode has increased significantly. The memory effect has faded away from the teeth, although some very advanced users continue to “train” the batteries of their devices using the old memory.
Most smartphones on the market today are equipped with this type of battery.

But they also have disadvantages, and quite unpleasant ones:
  • A narrow range of operating temperatures.
  • Potential risk of destruction of the battery during deep discharge or recharging.
  • Rapid "aging", after 2-3 years of disabling the battery.
  • Pretty high cost.

It should be said that since the first appearance in stores of this type of power source, the shortcomings have been substantially leveled. But manufacturers wanted more. First of all, they were not satisfied with a high enough cost, so another type of battery was created.

In them, an explosive electrolyte gave way to a polymer mass. The price of such power supplies has decreased slightly, mainly due to the need to use more complex protective circuits. Power is also not too increased. But solid polymer is good because it has untied the hands of the designers, allowing it to choose the shape and size of the element at its discretion. Around this time, many ultra-slim smartphones with non-removable batteries appeared. Both types of lithium batteries have a common drawback: regardless of the intensity of use and the number of charge / discharge cycles, their capacity gradually decreases. And already after a couple of years, the gadget with a clear conscience can be thrown away. Or, say, hang on the wall as an exotic decoration. It is believed that the lithium-polymer type is a bit less “tenacious”, but this information is from the category of myths, there are examples that both confirm and refute this statement. So for sure it is not possible to distinguish truth from fiction.

How it work?
Batteries work due to the voltage difference between the two metal plates immersed in the electrolyte solution. For the first time a current source operating on this principle was created in the 19th century. One plate in it was copper, the second - zinc, which very quickly dissolved.

The voltage difference can be explained by the example of the analogy with two containers with liquid, which are connected by a tube. In order for the water in the tube to start moving, you need to create a level difference, for example, to raise one tank above the other. Gradually, water will flow from the left bottle to the right. When the levels are equal, the flow of water stops. For a battery, this means full discharge.

To recharge it, you must return the water to the original container. For example, using a scoop or cup. If you draw water from the right bottle and pour it into the left bottle, the battery will charge. Of course, you need to scoop at the same speed as water flows through the hose. Otherwise, the battery will again be discharged.

Structurally, the battery itself is an extremely simple device. These are two long sheets of graphite and lithium oxide with cobalt. They are lubricated with electrolyte and rolled into a roll. Lithium-ion battery is ready.

Battery Myths.
It is widely believed that immediately after buying a Li-Ion-battery you need to “swing” - to spend several cycles of full charge-discharge. Usually - from three to five. This myth is not very harmful for batteries, but, nevertheless, it spends its work cycles.
The property of Li-Ion batteries is that they do not have a memory effect, as was the case with NiCd batteries. This effect was that if you charge a not completely discharged NiCd battery, its capacity would drop. Li-Ion has no such features. Moreover, the manufacturer guarantees that the battery capacity does not decrease in 300 discharge-charge cycles.

Once again: a player, phone, walkie-talkie, PDA, tablet, watch or any other mobile device with a Li-Ion is "useless" to "train".

Li-Ion batteries do not like too much charge and discharge. The manufacturer guarantees 300 cycles, but this does not mean that for 301 cycles the battery can be thrown away. Everything will depend on the operating conditions. "Greenhouse" conditions for Li-Ion is the maximum charge up to 80%, and the minimum discharge - up to 40%. Some models of laptops allow you to set these parameters in the service software, prolonging the "life" of the battery. Also, batteries irrevocably lose capacity at temperatures below zero degrees and when heated above +40 degrees. Therefore, it is better to protect the gadgets from frost and high heat.

Why is the battery on the phone swelled?
No matter how diligent a user has a mobile phone, sooner or later he may encounter a completely unexpected problem - why is the battery on the phone swollen?

Cheats up your battery!
Any battery works due to complex chemical processes that take place in it. When chemical reactions are disturbed, gas begins to evolve and pressure rises, which leads to swelling of the battery. But the reasons forcing the reaction to proceed with a violation may be many and, most often, they are associated with improper operation of the phone.

The reasons why the battery may swell on the phone:
If the battery is swollen in the first weeks of using the phone, most likely it is a factory defect. Such a phone should be handed over under warranty;
The battery life has expired (from 2 to 5 years) and must be replaced with a new one.

Violation of the use of the phone and non-compliance with the attached instructions:
  • The phone, which often falls, is subjected to severe shocks, which can lead to chemical disturbances in the battery and its swelling.
  • When buying a phone, every person probably listens to a recommendation from a consultant on how to properly charge the phone, but not everyone listens to it.
  • Improper charging can also be the reason why the battery on the phone is swollen.
  • If the phone periodically “bathes”, then the battery will easily fail. Water ingress, in principle, is detrimental to the entire device. - A non-original charger will quickly lead to swelling of the battery, and the reason for this will be incorrect charging of the phone with unsuitable voltage.
  • The conditions of the environment in which the phone is used also affect the life of the battery.
  • Temperature extremes, extreme heat or cold, can lead to swelling. What to do with a swollen battery.

A worn out battery needs to be replaced, because it is quite difficult and even dangerous to use a bloated one (the battery will not keep the charge well or will not charge at all, the phone's lid will not close well, there is a possibility of an explosion). A blown-up battery should not be stored at home, but should be disposed of properly. Ideally, pass it to the manufacturer.

Thanks to all!
Related thread:
[How it Works #4] Type of Touchscreen and How it Work!
[How it Works #5] Type of Display and How it Work!
[How it Works #6] Camera in smartphone, and how it works!


Number of participants 11 Experience +139 Pack Reason

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2019-05-27 01:29:18
Favorites57 RateRate

Pro Bunny

minami- | from app


Thanks for the info and tips! I always try to charge up to 80% for battery charge efficiency.
2019-05-27 02:05:46
Thanks for sharing this with us.
2019-05-27 02:27:28

Mi Pilot

tZe_vitamin | from Redmi Note 7


I dont go under 10% and when I charge my battery go to 90%
2019-05-27 03:10:23

News Reporter

ᎮᏒᎥᏁፈᏋ | from Redmi Note 4X


Well Explained !!
2019-05-27 04:08:02

Pro Bunny

Andler1968 | from MI 8 SE


Very good Info. thanks
2019-05-27 05:03:55

Advanced Bunny

Dilireba | from MI 8


Nice info anyway....
2019-05-27 05:26:17

Master Bunny

Erdinçer | from MI MAX 2


thanks for the good information
2019-05-27 05:58:47

Beta Team-Global

georan. | from Redmi Note 5 Pro


thanks for information for safe using battery
2019-05-27 06:02:03

Advanced Bunny

Proteus8 | from Redmi Note 7


really good and useful information, thanks for sharing
2019-05-27 06:20:00

Master Bunny

2/149G | from Redmi Note 4


pretty helpful information .
2019-05-27 06:25:38
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