From the year 2016, the news of fire accident of a international branded smart phone appeared frequently in the media. Many people wonder, a small cell phone neither have explosive materials and components that is easy to cause fire, nor does it in the case of high pressure and high temperature, why did fire explosion happen? We should talk from the phone external phone battery.
Smart phones use lithium-ion batteries. In the early 90s of last century, lithium-ion external phone battery began to become a common component of mobile phones and other equipment. Small-size and high-energy lithium-ion cell battery works like this: the battery has positive electrode, negative electrode, separator (also known as the diaphragm) and electrolyte. The charging and discharging functions are achieved through the movement of lithium ion between the positive and negative back. What needs to be emphasized here is that the positive and negative electrodes can not directly contact with each other during the process of charging or discharging. Otherwise, short circuit may occur, causing the battery for phone to become abnormally hot and even cause dangerous accidents such as explosion.
So, how to avoid the positive and negative batteries from direct contacting with each other and ensure that there is sufficient electrolyte between the positive and negative electrode for lithium ions to move? The isolation membrane plays a key role here. Isolation film is actually a non-conductive film, it can not only isolate the positive and negative electrode, but also provide sufficient electrolyte for lithium ions to move.
Lithium-ion external phone battery has its unique advantages. It not only has lower toxicity, lower cost, but also support fast charge and discharge, have larger output power, longer service life, lighter weight and higher energy density, compared with NiMH, NiCad and other batteries. It can store more energy to extend battery life with small size.
Some cell phone external phone battery producers blindly downsize the battery for the sake of competition and the pursuit of profit maximization. They know that the energy density of cell phone batteries is close to the "limit", there is little room for improvement. However, in order to provide more energy in a smaller volume, they can only take the risk of squeezing the space occupied by the barrier film, so as to install a little more positive and negative materials to enhance the battery's energy density and cell phone life, but this ultra-thin isolation film are particularly stringent on the processing requirements, a slight mistake may cause quality defects, which would lead to the battery short circuit, this is the direct reason for the cell phone explosion.
In fact, as early as the beginning of this century, people have found the problem of cell phone batteries explosion, but now the problem appears more frequently. For consumers, to deal with external phone battery problems, first, use batteries with shorter life, it is better to charge the phone for many times than to use unqualified batteries; Second, do not rush to use cutting-edge technology products, it’s better to use it till it becomes mature to avoid the damage from products with hidden danger. As for the manufacturers, they should mainly focus on safety when designing products, and complete the required performance testing and inspection.
We (Shenzhen Wanshuntong Science & Technology) are manufacturer of batteries and power banks, supplying high quality batteries and power banks to consumers from all over the world. As one part of this area, we are devoted to supplying top quality batteries and power banks, and develop new technology to enhance external phone battery and power bank buyer's using experience.