Samsung Note 7 explosion: It's like walking on a towering building

In late August and early September, news about Samsung Note7 explosions appeared occasionally, and Europe began to recall the phone during the same period;

On September 15, the phone was also recalled in the United States. According to foreign media reports, the United States received 26 reports of burns and 55 reports of property damage.

Before the Mid-Autumn Festival, Samsung began to recall the first batch of domestic experience machines (informal retail version, totaling 1,858 units).

The first domestically produced Note7 exploded on the first day after the holiday

"**Cellphone spontaneously combusts" is a topic in mobile phone news that has been reported once or twice every few months in the past few years; but this is the first time that Samsung has made a cell phone spontaneously combust more well-known than the press conference.

Less than a month after being on the market, Samsung Note7 recalled 2.5 million phones worldwide; as a mobile phone, its sales are growing very fast.

"If you fly fast, you will fall hard." At the same time as the 1 million mobile phones were recalled in the United States, there were 92 reports of severe overheating of this model of mobile phones (including burns and property losses for users) in the local area.

It's a pity that the Android flagship, which had hoped to compete with the iPhone 7, stumbled upon itself.

Some exaggerated statements added fuel to the fire

Among these rumors about Note7 explosion, some are true, and some are really unfair.

During the iPhone 7 launch event, a foreign user said that the Note7 caught fire and burned his jeep.

The aviation authorities also added fuel to the fire. According to information, more than 10 countries and regions have required that Samsung Note7 phones be banned from flights or checked baggage. For a phone priced at 6,000 yuan, it is equivalent to telling potential users: your phone cannot be used on the plane, or even brought with you. This is a feeling of being discriminated against.

For many users, this description seems to treat Note7 as a bomb. In fact, some foreign airlines have indeed strengthened the control of Note7 phones, such as not allowing them to be turned on or charged on the plane. But other rumors are deliberately exaggerated or misinterpreted, such as "major domestic airlines ban Samsung phones" and so on. If you have taken a plane in China, you will know a common sense: they originally prohibit users from turning on or charging their phones on the plane, and the same is true for iPhone, Huawei, and Xiaomi, even if they are in airplane mode.

Others were pure pranks, such as the Note7 burning a truck after burning a jeep - that was just a prank by foreign users, and the public who did not know the truth took it seriously.

Why did it explode? This is a junior high school chemistry question

The core problem is the invisible battery.

According to various sources, the explosions mainly occurred in mobile phones with batteries provided by Samsung's subsidiary SDI (Samsung SDI Co.).

The overall structure of a lithium-ion battery is shown in the figure: positive electrode, negative electrode, and electrolyte in the middle. The current between the electrodes is completed by the conduction of electricity between ions, and the positive and negative electrodes are separated from each other by a diaphragm. Because our junior high school teacher said that the contact between the positive and negative electrodes will cause a short circuit.

The problem with this batch of batteries is that the quality control of the diaphragm is poor, causing the anode and cathode to directly contact and short-circuit. "After a short circuit, the device will heat up." This basic common sense will make the chemical elements in the battery more active and the reaction more intense - the temperature is higher.

This high temperature occurs during charging (excessive chemical reactions at the anode, causing the temperature to rise) and also during discharge (the cathode's oxide and electrolyte combine). These effects don't happen the first time, but gradually accumulate, reaching a critical point: the temperature promotes chemical reactions, which generate more heat.

In this vicious cycle, the battery will instantly reach a high temperature of 150 degrees, expand in a confined space, combustible objects will burn, and engineering materials will melt - strictly speaking, this is called spontaneous combustion, and to put it more seriously, it is an explosion.

Samsung's response: No overall recall in China, explanation difficult to convince the public

Note7 has been recalled in various regions around the world, with a total estimated number of more than 2.5 million units, and initial direct economic losses of $1 billion. In order to ensure that the unrecalled units will not have problems again, Samsung has forced Note 7 users to push system updates. The main content is to add a battery detection function. For batteries with no problems, the top icon will turn green (previously the default was white). For users with problems, the charging capacity will be limited to 60%. The battery capacity has dropped from 3500 mAh to 2100 mAh after the update, forcing users to change their phones.

Samsung has also filed a recall plan with the China Quality Inspection Bureau, but there are only 1,858 defective review phones in China, so not all of them need to be recalled. The reason is that the Chinese version of the Galaxy Note7 sold in the Chinese market since September 1 uses batteries supplied by ATL (New Energy Technology Co., Ltd.) instead of SDI's problematic batteries, and is not included in this recall plan. For detailed reports, please see here: Samsung announced that it will actively replace the Note 7 review phones in China, but only 1,858 of them are available.

However, on September 18, a user in Baidu Tieba claimed that his domestic retail version of Note7 also exploded. But Samsung officials did not give a clear explanation on this matter. On the contrary, the post has now been deleted.

Are there really no problems with phones that were officially released after September? Do Chinese products really not need to be recalled? Or has the cause of the battery explosion not yet been determined?

Samsung has not yet made any statement on the matter. Compared with its competitors, Samsung's crisis public relations is not up to standard. Users who don't know the truth have already turned to Apple.

Summary: It's like walking on a tall building

Mobile phones exploded. The key is that some were recalled and some were not. Whether the ones that were not recalled had problems or not is the bomb buried in the minds of users.

As of now, the global recall of Samsung Note7 is still in progress. Domestic users are skeptical about the statement that "there is no problem with the domestic version of Note7". In the short term, Samsung has lost more than one billion US dollars; in the medium term, Samsung's plan to use Note7 to grab iPhone 7 market share has basically failed; in the long term, this is a problem of brand security.

"What is safety? A skyscraper with a hundred floors and a glass floor is safe according to architectural theory; but what determines the sense of security? If you look down, you will never choose to step on it."

It is said that Samsung will rename the product Note7S - S means safe.

But you still don't dare to put your phone next to your pillow before you go to bed to charge it. This may be a problem that Samsung needs to solve in the future.

Appendix: How to avoid mobile phone explosions and the harm they cause

"Good fortune is not a disaster, but disaster is inevitable." This sentence is a pain in the heart for Samsung Note 7 users, but for other mobile phone users: improper use can also cause the phone to explode. How to avoid it, the following may help:

1. Use the original charging cable

This is the most important point. Different mobile phones have their own charging specifications. Using incompatible charging equipment may cause the phone to overheat and explode. If the power adapter is plugged into the socket for a long time, the charger will age over time, resulting in poor contact and causing a fire.

2. Keep away from your phone while charging

It is best not to play games, answer calls, or sleep for a long time while charging. Although it is not certain whether danger will occur, staying away from the phone when danger may occur can at least avoid personal injury.

3. Cool down your phone

Excessive use or improper charging of the phone will cause it to become very hot. Do not continue to use or charge the phone at this time. If you notice that the phone is too hot, you can choose to turn it off to minimize the danger.

As a winner of Toutiao's Qingyun Plan and Baijiahao's Bai+ Plan, the 2019 Baidu Digital Author of the Year, the Baijiahao's Most Popular Author in the Technology Field, the 2019 Sogou Technology and Culture Author, and the 2021 Baijiahao Quarterly Influential Creator, he has won many awards, including the 2013 Sohu Best Industry Media Person, the 2015 China New Media Entrepreneurship Competition Beijing Third Place, the 2015 Guangmang Experience Award, the 2015 China New Media Entrepreneurship Competition Finals Third Place, and the 2018 Baidu Dynamic Annual Powerful Celebrity.