The positive and negative electrode materials used in lipo battery are the same as liquid lithium ions, and the positive electrode materials are divided into lithium cobaltate, lithium manganate, ternary materials, and lithium iron phosphate materials, and the negative is extremely graphite, and the working principle of the battery is the same. Their main difference is the difference in electrolytes, liquid lithium-ion batteries use liquid electrolytes and polymer lithium-ion batteries are replaced by solid polymer electrolytes, this polymer can be “dry”, it can also be “colloidal”, most of the current use polymer gel electrolyte.
Polymer lithium-ion batteries are widely used in notebook computers, smartphones, and other mobile appliances because of their small size and lightweight. In the case of modern smart products, their security is particularly important, especially when the mobile phone is 24-hour, more than half or more are carried on the body. So is the safety of polymer lithium-ion batteries reliable? Will it explode?
lipo battery generally uses flexible packaging, and the shell is thin, and relatively soft, from a safety point of view, under normal conditions of use, storage will not explode unless man-made strong damage causes its short circuit. But anything is not absolute, if the instantaneous current is large enough to short-circuit, the battery’s spontaneous combustion or burst is not impossible, mobile phones and tablet computer security accidents are caused by this situation.
Polymer lithium-ion battery precautions
Short circuit: generally internal short circuit, external short circuit, etc. Generally, it is easy to occur during the charging process, and poor bonding between battery plates will also cause short circuits.
Although most lithium-ion batteries now have protection circuits that prevent short circuits and explosion-proof wires, in many cases, this protection circuit may not work in various cases, and the explosion-proof wires can play a limited role.
Overcharge: lipo battery, if the charging voltage is too high, the time is too long, the internal temperature of the battery continues to rise, the internal pressure of the battery increases, and the pressure reaches a certain degree, causing expansion and rupture. Overcharge and over-discharge will destroy the reversibility of the chemical substances inside the battery, thus seriously affecting the life of the battery.
The chemical properties of lithium are very active, it is easy to burn when the battery is charged and discharged, the battery continues to heat up, the gas generated during the activation process expands, the internal pressure of the battery increases, and the pressure reaches a certain degree, such as the shell is scarred, it will break, causing leakage, fire, and even explosion. Polymer lithium-ion batteries only expand.
Damaged: The battery is crushed and the cell is punctured. Because polymer lithium-ion batteries are colloidal electrolytes, it is difficult to reach the degree of explosion.
Use environment: Avoid use in high-temperature and low-temperature environments. A high temperature of more than 60 ° C will cause irreversible damage to the isolation film inside the battery, resulting in battery scrap. Too low a temperature will reduce the performance of the polymer lithium-ion battery, resulting in the battery capacity can not be released, can not be used.
Polymer lithium-ion battery from the above conditions can be seen that safety performance is still good, of course, not to say that the polymer lithium battery will not explode, but relative to the liquid battery, the probability of the polymer lithium battery explosion is very low, it will not be so popular on mobile electronic devices.
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