What is a cell phone

Name: cell phone

Hanyu Pinyin: shǒu jī

English: cellphone, mobile telephone

Additional Explanations: handset, combined set, mobile phone

Abbreviation for handheld mobile telephone.

[edit paragraph]Introduction

Mobile phone, usually called cellular phone, Japan and Hong Kong and Taiwan are usually called handheld phone, handset, and in the early days there is a big brother of the common name, is a portable telephone terminal can be used in a wider range.

Currently the most widely used worldwide are the so-called second-generation cell phones (2G), mainly GSM and CDMA. They are digital, in addition to voice communication, but also can send and receive text messages (SMS, SMS), MMS (MMS, multimedia messaging), wireless application protocol (WAP) and so on. In mainland China and Taiwan, GSM is the most popular, and CDMA and PHS cell phones are also popular. The entire industry is currently in the process of migrating to the third generation of cell phones (3G).

The exterior of a cell phone should generally include at least one LCD display and a set of buttons (some phones with touchscreens have fewer buttons).

The telephone keypad part of the cell phone in addition to the typical telephone functions, but also contains a PDA, game consoles, MP3, cameras, photography, recording, GPS and other more functions, there is a tendency to the development of PDA with cell phone functions.

The phone's mouth bearing, ear bearing and the corresponding microphone, handset are installed in a single handle. Older known as portable phone, portable, big brother, is portable, can be moved in a larger range of telephone terminals.

[edit]History of development

1G

The first generation of cellular phones (1G) refers to analog cell phones, that is, in the 1980s and 1990s in Hong Kong and the United States and other film and television productions appeared in the big brother. The first person to develop the Big Brother was Dr. Cooper of Motorola in the United States. Due to the limitations of the battery capacity and analog modulation technology requires a large antenna and the development of integrated circuits and other constraints, the appearance of this phone is four-square, can only be mobile is not portable. Many people called this kind of cell phone "brick" or black diamond.

This cell phone has a variety of systems, such as NMT, AMPS, TACS, but basically the use of frequency division multiplexing can only be used for voice communications, the reception effect is not stable, and the lack of confidentiality, the use of wireless bandwidth is not sufficient. In this case, the cell phone is similar to a simple radio duplex radio, the call is locked in a certain frequency, so the use of FM radio can eavesdrop on the call.

2G

The second generation of cell phones (2G) is also the most common. Usually these phones use PHS, GSM or CDMA, which are very mature standards with stable call quality and suitable standby time. In the second generation, in order to meet the needs of data communication, some intermediate standards are also supported on cell phones, such as GPRS for MMS and WAP services for Internet access, as well as a variety of Java programs.

3G

3G, which stands for 3rd Generation, refers to the third generation of mobile communication technology. Relative to the first generation of analog cellular phones (1G) and the second generation of digital cellular phones such as GSM, CDMA, etc. (2G), the third generation of cellular phones generally refers to a new generation of mobile communication systems that combine wireless communication with multimedia communication, such as the international Internet. It is capable of handling various forms of media such as images, music, video streaming, etc., and providing a wide range of information services including web browsing, teleconferencing, and e-commerce. In order to provide such services, the wireless network must be able to support different data transmission speeds, i.e., at least 2Mbps (megabytes per second), 384kbps (kilobytes per second), and 144kbps in indoor, outdoor, and driving environments, respectively.

3G Mobile Phones

In contrast to the first generation of analog cell phones (1G) and the second generation of digital phones such as GSM and TDMA (2G), 3G communications are known by a wide variety of names, with the ITU referring to it as the IMT-2000 standard, and European telecom giants referring to it as "UMTS". The European telecom giants call it "UMTS" Universal Mobile Telecommunications System.

At present, there are three international standards for 3G handsets: Europe's WCDMA standard, the U.S. CDMA2000 standard, and the TD-SCDMA standard proposed by Chinese scientists.

Now "3G communication" is about to become a mantra on people's lips, the so-called 3G, in fact, it is known as the 3rd Generation, the Chinese meaning is that the third generation of digital communications. 1995 came out of the first generation of digital cell phones can only voice calls; and 1996 to 1997, the emergence of the second generation of digital cell phones will increase the number of voice calls; the second generation of digital cell phones will increase the number of voice calls. The second generation of digital cell phones that appeared between 1996 and 1997 added the ability to receive data, such as e-mail or web pages; the main difference between the third generation and the first two generations is the increase in the speed of transmitting sound and data, which is able to handle images, music, video streaming and other forms of media, and to provide a wide range of information services, including web browsing, teleconferencing, e-commerce, etc. The first generation of analog cell phones was introduced in 1995, and the third generation is actually called 3rd Generation. Compared to the first generation of analog cellular phones (1G) and the second generation of digital cellular phones such as GSM and TDMA (2G), 3G communications are known by a variety of names, including the ITU's "IMT-2000" (International Mobile Telephony 2000) standard, and the European telecommunication giants' "UMTS" Universal Mobile Telecommunications System (UMTS) standard. UMTS" Universal Mobile Telecommunications System. The standard specifies a transfer rate of 144 kbps for mobile terminals moving at vehicle speeds, 384 kbps outdoors at rest or on foot, and 2 Mbps indoors, but these requirements do not mean that users can achieve a usable rate of 2 Mbps, as indoor rates will also depend on detailed frequency planning within a building and how closely an organization works with its operators.

The cell phone of the future

The cell phone of the future will favor security and data communication. With enhanced privacy protection on the one hand and enhanced data service development on the other, more multimedia features will be introduced, and the cell phone will have more powerful computing capabilities, becoming a personal information terminal rather than just a call and text messaging function.

Mobile phones will become more intelligent, miniaturized, secure and multifunctional.

Current cell phones

The most widely used cell phones in the world are GSM and CDMA phones. In mainland China and Taiwan GSM is the most common, CDMA and PHS cell phones are also very popular, these are the so-called second-generation cell phones (2G), they are digital system, in addition to voice communication, but also can send and receive text messages (SMS, SMS), MMS (technology) | MMS (MMS, multimedia newsletters), wireless application protocols (WAP) and so on.

[edit]Types of cell phones

The type of cell phone, as the name implies, refers to the external type of cell phone, and now the more commonly used classification is to divide the cell phone into folding (single-screen, dual-screen), upright, slider, rotary and other categories.

Single-screen folding

Folding cell phone refers to the cell phone for the flip type, to flip open the cover to see the main display or keys, and only one screen, then this phone is called a single-screen flip phone. At present, the market also introduced a dual-screen flip phone, that is, in the flip cover has another secondary display, this screen is usually not big, usually can show the time, signal, battery, caller ID and other functions.

Upright

Upright cell phone means that the cell phone screen and keys are in the same plane, and the cell phone has no flip cover. The main feature of an upright phone is that you can directly see what is displayed on the screen.

Slider type

Slider type cell phone mainly refers to the cell phone to be pulled to see the whole body. Some models are just sliding the lower cover to see the keys; while others are pulling up on the screen portion to see the keypad. In a way, slide phones are an extension and innovation of flip phones.

Watch-style

Watch-style cell phones are mainly wristwatch-like cell phones that are compact in design and have the same functionality as a regular cell phone.

Rotating type

This type is similar to the sliding type, the main thing is to see the keyboard after 180° rotation.

[edit]Types of cell phones

Business cell phones

Business cell phones, as the name implies, are cell phones that target business people or people working in state agencies. Because of the powerful functions, business cell phones are favored. Industry experts point out that "a good business phone should help users achieve both fast and smooth communication and efficiently complete business activities."

Camera phones

Camera phones are a type of cell phone, that is, cell phones with built-in camera functions. The world's first camera phone, the J-SH04, was manufactured by Sharp Corporation of Japan in November 2000, and it used a CMOS image-sensing module (CMOS for short) as a surprise, because CMOS is more power-efficient than the CCDs used in digital cameras at the time. The reason for this was that CMOS was able to save more power than the CCDs used in digital cameras at the time.

Phones for the Elderly

With the improvement of people's health and the extension of the population's life expectancy, the elderly account for an increasing proportion of the population. Accounting for nearly one-third of the population proportion of the elderly group, they need to belong to their own cell phone, cell phone function to strive for easy operation, Sailot first launched the elderly cell phone, many manufacturers have followed suit to develop their own brand of cell phones for the elderly.

Practical features: large screen, large font, large ringtone, large buttons, large call tone;

Easy to live: professional software (visualization, menu is simple, the structure is clear), one-key dialing, banknote detection, flashlight, hearing aids, voice read phonebook, read text messages, read the incoming call, read the dialing number)

Not only that but also to improve the quality of life for the elderly function! External radio, Peking Opera, one-key distress (press the key to send out a high-decibel distress tone, and at the same time to the designated number to dial out the distress call, send out the distress text message).

Music cell phone

Music cell phone, in fact, is in addition to the basic functions of the phone (making calls, sending text messages, etc.), it focuses more on the music playback function. Characterized by good sound quality, long-lasting music playback time, and music playback shortcuts. Currently the better music phones are the NOKIA XM series and Sony Ericsson's WALKMAN series, and other brands are also involved in this type of phone.

Gaming phones

Gaming phones, that is, cell phones that are more focused on gaming features. It is characterized by having buttons on the body that are specifically set up for gaming or convenient for gaming, and the screen is generally not small. An example is the Nokia N-GAGE platform phone (Nokia N81).

Invisible cell phone

Invisible cell phone is a high-end intelligent handheld computer phone, in addition to superb business functions and pen handwriting, as the name suggests, the most sought after is its "invisible" function. The so-called "invisible", first, phone calls, text messages can be answered at will, receive, do not want to answer, receive all be filtered. Second, in addition to the owner himself, no one can not see the sent and received text messages, can not see the call records. Thirdly, important business cards are automatically hidden. The most powerful thing is not simply the problem of not seeing, is that others simply can not know whether there is the existence of calls and text messages and important business cards. This is a great way to keep your phone safe and secure, even if you lose it.

Smartphone

Smartphone, to put it plainly, is a simple "1 + 1 =" formula, "PDA + cell phone = smartphone". In a broad sense, smart phones in addition to the phone's call function, but also has a PDA most of the functions, especially personal information management and wireless data communications based on the browser and e-mail functions. Smart phones provide users with sufficient screen size and bandwidth, which is convenient to carry around, but also provides a broad stage for software operation and content services, and many value-added services can be carried out in this regard, such as: stocks, news, weather, transportation, commodities, application downloads, music and picture downloads, and so on. The integration of 3C (Computer, Communication, Comsumer) smart phone will become the new direction of the future development of cell phones.

A smartphone must have a few conditions:

1, with all the functions of an ordinary cell phone, able to make normal calls, text messaging and other cell phone applications.

2, with the ability to access the Internet wirelessly, that is, you need to support the GSM network under the GPRS or CDMA network under the CDMA 1X, wifi, or 3G network.

3, with PDA functions, including PIM (personal information management), calendar, task scheduling, multimedia applications, web browsing.

4, with an open operating system, the operating system platform, you can install more applications, so that the smartphone can be unlimited expansion of functionality.

Operating Systems

▼Symbian OS: Fashionable because it's popular, with the broadest support going further and further.

Symbian is now well-designed, stable, and supported by many vendors, with a promising future. Now it has a very strong web application. 9-key one-handed operation is very comfortable. Symbian is very much like a combination of Windows and Linux, with a good interface, using kernel and interface separation technology, lower hardware requirements, and support for C++, VB and J2ME. representative models: Nokia N95, Nokia E90, Nokia N96, etc.

▼WM: Microsoft's software platform for Pocket PCs and Smartphones. Windows Mobile extends the familiar Windows desktop to personal devices.

Windows Mobile is Microsoft's "mobile version of Windows" for handheld devices, and the devices that use the Windows Mobile operating system include cell phones, PDAs, and portable music players.

There are four types of Windows Mobile operating systems. There are four types of Windows Mobile operating systems, namely Windows Mobile for PocketPC Edition, Windows Mobile for PocketPC Phone Edition, Windows Mobile for Smartphone Editon, and Windows Mobile for Portable Media Centers. The latest version is Windows Mobile 6.1. Advantages: 1, the interface is similar to desktop Windows, which is easy to be operated by people familiar with computers. 2, rich pre-installed software, built-in Office Word, Excel, Power Point, which can be browsed and even edited, built-in Internet Explorer, Media Player. 3, the software is not available in Windows Mobile. 4, the software is not available in Windows Mobile. Explorer, Media Player. 3, computer synchronization is very convenient, fully compatible with Outlook, Office Word, Excel, etc. 4, powerful multimedia functions, with the help of third-party software can play almost any mainstream format of audio and video files. 5, touch operation, comparable to the iPhone. 6, a wealth of third-party software. Especially the dictionary, satellite navigation software can run. Disadvantages: 1, the operation is more complicated for people who are not familiar with computers. 2, the camera is currently up to 5 megapixels (Samsung I900, 2008). 3, the hardware requirements are higher. 4, the size is slightly larger, many operations need to use a stylus. Windows Mobile Pocket PCs and cell phones of the mainstream hardware configuration: CPU: 195-624 Mhz, the main Chip manufacturers: Intel, Texas Instruments, Samsung, Qualcomm, etc., Memory: 64-128MB Ram (for program operation), 128-256MB Rom (for third-party programs and user file storage), Display: 240x320 or 480x640, 65,000 colors, 2.4-3.5 inches, Expansion Card: 2.4-3.5 inches. 3.5 inches, Expansion card: Micro SD or SD, SDHC, High-end models have built-in WiFi, GPS, FM radio, 3G or 3.5G high-speed network, Bluetooth and USB port for synchronization with a computer. HTC Diamond (Diamond), the flagship model of Windows Mobile, caused a sensation in the world of cell phones and mobile devices, and its momentum is directly comparable to that of the iPhone, with the following key performance: Windows Mobile 6.1 Professionel, CPU: Qualcomm 524 Mhz, 128 MB Ram, 256 MB Rom, 4 GB internal storage, 7.2Mb/s HSDP. 7.2Mb/s HSDPA 3.5G high-speed Internet access, 2.8-inch VGA display, WiFi, GPS satellite receiver, FM radio, Bluetooth 2.0 port, 3-megapixel camera with flash, 3D picture display, Micro SD memory card.

▼Linux: Gives you a reason to love it, lack of security and low performance.

Linux has the advantages of open source code, low software licensing costs, and abundant application development talent resources, making it easy to develop personal and industry applications. Started too late, there is no strong foundation. Representative models: Motorola A760, Samsung i519.

▼Palm OS: Please look at me again, single function, few users.

Palm, this system has very low hardware requirements, so the price can be well controlled, and power consumption is also very small. Remarkable features are far faster than other systems, comfortable operation, if you will not use the stability is not good (familiar with it will be fine). But there are fewer of them in China, and fewer Chinese who write software for it. Network applications are also poor. Representative model: Samsung SGH-i500Treo 600.

[Edit Paragraph]Mobile phone brands

Europe and the United States mobile phones

Nokia, Sony Ericsson, Motorola, Philips, Palm, HP, Apple, Blackberry, Disney, Alcatel, O2, i-mate, Vertu, mobiado, Ericsson Siemens, Sagem, Lucent, Google

Japanese and Korean mobile phones

NEC, SK, Sharp, Pantech, Kyocera, Vikai, Panasonic, Dongfanglong, Mitsubishi, Toshiba, Sanyo, Sony Ericsson, Hyundai, Samsung, LG,

China's mobile phones

Dopod, Lenovo, Celerity, Poguide, Qixi, Sharp, Konka, TCL Haier, BBK, Shenda, Asus, BenQ, Coolpad, OKWAP, Huawei, UTStarcom, ZTE ZTE, Hisense, OPPO, Skyworth, YouLiTong, GT Jiatong, CECT Gigabyte Sky, Long Aiken, ZTC Zhongtian, Daxian, Yitong, Tianyue, Changhong, Leroyal, Aox, Zhenhua Obi, Tianshida, Wanlida, Huali, Vickers, Qiaoxing, Huatong, Sanda, Hongkong Litong. Hengjiweiye, Huayu, Yitian, Jinpeng, Desai, Wanxitong, FIC Mass, Quanzhi, Hongkang, Shengtai, IDOTSD, Green Power, Dongxin, Shouxin, NJStar, Vaio, Guangxin, Elliott, Dupao, Putian, VOSIA, Aoxiang, Ke Sheng Communications, Zhongxun, Tianchuang, Gaoxinqi, Meizu, Hantai Fuzhongbao Huixun Sanjunet, Bonhomo, Morningside, Gaoke, Baojie, Xunhai, Nuozongyi. Newman, Jiayuan, Guoxin, Jinzheng, Yi Dong, Pryda, HKC, Zhaoxun, Dajun domain deep love, Gaosbel, Yichengyou, Xinda, Zhongheng, Lianxin, Zhongqiao, Kono, Zhi Zhi, YaXunDa, Tianyuan, new postal communications, Minteng, Kejian, Xiamen, Panda, Nanfang Hi-Tech, Datang, Topdibit, Wave, Zhongqiao Digital Source, Ziguang, UNISNEO, Ao Sheng, Beluga

Hong Kong line cell phone

Many friends have some misunderstanding about the concept of "Hong Kong line cell phone", thinking that Hong Kong line cell phone is a fake, quality problem goods. The Hong Kong line of cell phones is for the Hong Kong market sales of cell phones, in Hong Kong local these products are formal sales methods as well as sales channels. Hong Kong licensed products are not fake. A mention of the four words Hong Kong licensed goods some friends may have a feeling of trepidation, always feel that Hong Kong licensed goods are not reliable. On the contrary, Hong Kong licensed goods relative to domestic licensed goods is the authentic original goods. Because it is the original production, so there is absolutely no need to worry about the hardware, and in the operation and function is also the same as the domestic licensed goods. Because of the difference in tariffs between the mainland and Hong Kong, plus the manufacturers in the mainland and Hong Kong pricing is also different. Even in Hong Kong regular sales of cell phones, and the mainland region of the same model of cell phone between there is a big price difference. Some cell phone sellers, on the other hand, transfer products that are supposed to be sold in Hong Kong to mainland China through one way or another, and smuggle them back to Shenzhen directly from Hong Kong, so that Hong Kong licensed cell phones have labels on the back of the store and Hong Kong's mobile carriers.

Supplementary: Hong Kong cell phone in fact, there are licensed goods and parallel imports of points. Cell phones purchased at regular Hong Kong electrical appliance chain stores (e.g. Gome, Fung Chak and Broadway, etc.) will have invoices issued by the sellers. These phones are only called licensed products in Hong Kong and enjoy customer service after-sales services, such as one-year warranty, provided by the manufacturers (e.g. Nokia, Moto and Samsung, etc.). Some also offer a nationwide warranty. However, Hong Kong water cell phones purchased from parallel stores in Hong Kong do not have formal invoices, and none of them can enjoy customer service after-sales service in Hong Kong, and they can only pay for maintenance at the place of purchase. Because of the warranty, the Hong Kong line and Hong Kong water in the price is still not a small difference.

In fact, the mainland cell phone due to competition from the national series, the price itself is very cheap. There is basically no price difference between the domestic national line and the Hong Kong line in Hong Kong, and even the national line is a bit cheaper.

In China many merchants take Hong Kong water to pretend to be Hong Kong line, in fact, is a very unkind practice, because Hong Kong water will not be provided with warranty no matter where you get it.

The way to identify Hong Kong and Hong Kong water is actually very simple: Hong Kong goods charger plugs are always used in the British system of the big triangle head (three feet, each is a four-sided), while Hong Kong water is flowery and green everything.

Do Hong Kong phones come in simplified Chinese?

Generally speaking, the Hong Kong line is a traditional cell phone, the same there is Simplified Chinese, and the same as the domestic line are Simplified Chinese (in addition to the manufacturers of some models do not have Simplified Chinese, in addition to), if the menu is in English or other languages, the relative price will be cheaper.

Hong Kong cell phone warranty:

Hong Kong cell phone is warranted by the Hong Kong one year.

[edit]Related terms

Roaming

Roaming is a term commonly used by cell phone users. It refers to the fact that users of cellular cell phones can continue to use their cell phone handsets in some other region or country while they are away from their region or home country.

Roaming can only be carried out between domestic cities with compatible network standards and already connected to the Internet, or between regions or countries that have signed bilateral roaming agreements. To realize the roaming function is technically quite complex. First of all, it is necessary to record the location of the user, and there is also a set of profit settlement between the operating companies.

SIM card

Also known as subscriber identification card, SIM card is a data card for digital cell phones, which records the subscriber's identification and key, and can be used by the GSM system to identify the subscriber and encrypt the subscriber's voice information.SIM card effectively prevents the theft of, and merging with, and eavesdropping on voice information.

SIM cards are small and large cards with identical functions and are used in different types of digital mobile phones. A cell phone can only be used if it is equipped with a SIM card, which can be inserted into any cell phone of the same type, and the call is automatically charged to the cardholder's bill.

GPRS

GPRS is the acronym for "General Packet Radio Service", which is a new network superimposed on the existing GSM network, which makes full use of the equipment of the existing mobile network, adding some hardware equipment and software upgrades to the GSM network to form a new network logical entity. logical entity of the network. It is based on packet switching technology, the use of IP data network protocols, so that the existing GSM network data services break through the highest rate of 9.6kbit / s limitations, the highest data rate of up to 170kbit / s, such a high data rate for the vast majority of mobile users, has been more than enough. With GPRS, users can enjoy a wide range of high-speed data services, including e-mail, Internet browsing and other IP services, while on the move.

Dual SIM card

Dual SIM card refers to a cell phone that can hold two SIM cards at the same time, and both cards are in standby mode. Dual-card dual standby in the market generally refers to dual-card dual standby of the same network system, i.e., dual-card dual standby for GSM network, dual-card dual standby for CDMA network, and dual-card dual standby for PHS network; dual-card dual standby mainly refers to the first case, i.e., dual-card dual standby for GSM. At present, there are fewer, if any, dual SIM phones with CDMA and PHS on the market.

USIM card

USIM card is the third generation of cell phone card. Many people think that in the 3G era, most of the applications can only be realized by cell phones, and the limited resources on the card only need to realize the authentication function. Indeed, 3G applications are very complex, most of the applications can not be completed through the STK card alone. However, USIM card is not only able to do the simple authentication function, it has been proved that it is gradually transitioning to the mobile business platform, and even the final multi-application platform, and it is no longer difficult to realize e-wallet, e-credit card, e-ticket, and other applications on the cell phone. This feature makes the USIM card become a medium for cross-sectoral cooperation and interpenetration of operations in different industries, such as banks can participate in the operation of telecommunications and vice versa.

In addition to being able to support multiple applications, the USIM card also upgrades the algorithm in terms of security and adds a card-to-network authentication function, a two-way authentication that can effectively prevent hackers from attacking the card. At the same time, the USIM card's phone book is more powerful, with up to 500 phone numbers, and for each phone number, the user can choose whether or not to enter additional information, such as e-mail, aliases, other numbers, etc. The USIM card can also be used as a phonebook, which can be used to store up to 500 phone numbers.

Despite its stumbling steps, 3G is coming our way. The high cost of 3G licenses may be one reason why many carriers are hesitant to move forward, but more importantly, they are taking a wait-and-see approach to 3G adoption. Moreover, there are still a lot of problems to be solved in realizing multi-application based on USIM card, such as insufficient specification, lack of cell phones to support such multi-application, and more importantly, the coordination between operators and related enterprises or governmental agencies will increase the difficulty of such application. In any case, the third generation of mobile communication cards in this regard has been prepared for the technology, I believe that the USIM card-based multi-application will eventually be widely used in the 3G era.

[Edit Paragraph]Mobile Phone - First Aid Maintenance

Mobile phones are used day in and day out, and their usage rate is high, so when they encounter accidents or early degradation of their functions, the situation is relatively higher than that of any other electrical appliances in your home. To cope with such cell phone accidentally into the water, accidental fall caused by intermittent automatic shutdown and other cell phone will often appear disease, sent to the factory repair is certainly the best way, but if you have some basic knowledge of cell phone first aid, before sent to the maintenance of the first rescue, can reduce the loss of cell phone to save a life.

Rescuing a cell phone that's been in the water

It's most common for a cell phone to get wet in the rain and accidentally fall into the water, so if you're really that unfortunate, don't hesitate to turn off the power and remove the battery to avoid water droplets from corroding the board. Then send it for repair as soon as possible is the emergency response. In addition, using a hairdryer to dry the inside of the phone (warm air only) can also slow down the degree of water corrosion of the board, also an emergency solution.

If you put the battery back in and continue to use it, it may still work fine, but in half a month's time at most, the board you've ignored will be corroded beyond repair. The normal operation you saw before is actually just an illusion.

When drying your phone with a hairdryer, remember to keep the temperature to a minimum, as too much heat can deform the adhesive material.

Automatic shutdown of the rescue

Mobile phone in the power and in standby mode, but will suddenly automatically shut down the condition of many users have experienced, the reasons for which there may be the following possibilities:

1. lithium protection circuitry within the role of over-sensitive, and therefore a large current power outage

2. the battery itself has been aging

3. the phone Water ingress (some cell phones are not waterproof)

4. Dirt on the metal tabs in the battery contact area, resulting in poor power contact

5. Loosening of the joints between the battery and the cell phone.

If after checking, you find that it is the first two problems, then you must go to a specialized repair store to fix it.

But if it's the last two, the problem is just that the "battery metal plate" is dirty and oxidized, so if you use a glue stick to wipe it clean, the situation will be improved. And if you put paper or film between the battery and the phone, you can also solve the problem of poor contact caused by a loose battery.