The differences between lithium polymer batteries and ordinary power banks are as follows:
1. It is best to use lithium polymer batteries for power banks. Lithium polymer battery is an improved product of lithium ion battery. Compared with the popular lithium-ion battery, it has the advantages of large capacity, small size and safety, but it is also more expensive.
2. The battery cells of surface power banks are mainly divided into lithium polymer batteries and ordinary lithium batteries. The former use solid or colloidal polymer electrolytes, and the latter use liquid electrolytes. more lithium polymer batteries than 18650 lithium batteries on the power bank. Which one is better, polymer battery or 18650 battery, of course depends on the model of the power bank.
3. Ordinary power bank: Lithium-ion battery, commonly known as "lithium battery", is currently the battery system with the best overall performance. The negative electrode of lithium-ion batteries is a carbon material, such as graphite. The positive electrode is a transition metal oxide containing lithium.
4. Lithium polymer battery: Lithium polymer battery is a new generation of battery, entered the market in large quantities in 1999, except that the electrolyte of lithium polymer battery is solid polymer instead of liquid electrolyte; , the rest is the same because lithium-ion batteries are basically the same.
Will lithium batteries explode when used as power banks?
The difference between the two:
Lithium batteries and lithium-ion batteries (polymers are also lithium-ion batteries) LA lithium battery is a type of lithium metal or lithium alloy negative electrode material. Due to the highly active chemical properties of lithium metal, the processing, storage and use of lithium metal have very high environmental requirements.
The negative electrode of lithium-ion batteries is made of intercalated structural materials such as graphite. In the battery, lithium ions move between the positive and negative electrodes, making it much safer than lithium batteries.
Lithium-ion batteries and lithium-polymer batteries. The electrolyte in lithium-ion batteries is liquid, while the electrolyte in polymer batteries is in gel or solid form, which is safer.
The packaging of lithium polymer battery cases and lithium batteries is slightly different. Lithium batteries are generally packaged in steel cases (18650 or typebutton 2320), while lithium polymer batteries are packaged in aluminum-plastic packaging films. That is to say soft batteries.
Lithium batteries
Have a higher energy-to-weight ratio and energy-to-volume ratio;
High voltage, the voltage of a single battery lithium battery is 3.6V, which is equivalent to 3 batteries. Series voltage of nickel-cadmium or nickel-metal hydride rechargeable batteries;
It has low self-discharge and can be stored for a long time, which is the most important. advantage of this battery;
No memory effect. Lithium batteries do not have the so-called memory effect of nickel-cadmium batteries, so lithium batteries do not need to be discharged before being charged;
< p>Long lifespan. Under normal working conditions, the number of charge/discharge cycles of lithium batteries is well over 500;they cancan be loaded quickly. Lithium batteries can generally be charged with a current of 0.5 to 1 times the capacity, shortening the charging time to 1 to 2 hours;
They can be used in parallel at will;
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Since the battery does not contain cadmium, it contains heavy metal elements such as lead and mercury and does not pollute the environment. It is the world's most advanced green battery;
Lithium-ion battery
High voltage, the working voltage of a single battery can reach 3.6-3, 9 V, three times that of Ni-Cd and Ni-H batteries.
Specific energy is important. The actual specific energy that can currently be achieved is 100 to 125 Wh/kg and 240 to 300 Wh/L (2 times that of Ni-Cd, 1.5 times that of Ni-MH). ). In the future, with the development of technology, with the development, the specific energy can reach 150Wh/kg and 400Wh/L.
The lifespan ist long, usually more than 500 times, or even more than 1,000 times. For electrical appliances with low current discharge, the battery life will double the competitiveness of the electrical appliance.
It has good safety performance, no pollution and no memory effect. As the predecessor of Li-ion, lithium batteries easily form dendrites and cause short circuits, which narrows its application areas: Li-ion does not do this. contain cadmium, lead, mercury and other elements that pollute the environment: a major disadvantage of Ni-Cd batteries with certain processes (such as the sintered type) is the "memory effect", which seriously restricts the use of batteries, but Li-. ion does not have this appearance at all.
Self-discharge is low. The self-discharge rate of fully charged Li-ion at room temperature after one month of storage is about 10%, which is much lower than the 25-30% of Ni. -Cd and 30% of Ni and MH -35%.
It can be loaded and unloaded quickly. With 1C load, the capacity can reach more than 80% of the rated capacity.
The operating temperature range is high, the operating temperature is -25 to 45°C. With the improvement of electrolyte and positive electrode, it should be extended to -40 to 70°C.
The external batteries currently on the market use lithium-ion batteries. The only difference is whether they use soft batteries (often called lithium polymer batteries) or 18650 batteries. As long as the battery itself is produced by a regular manufacturer, its safety is always guaranteed. The safety of the external battery also depends on the circuit. If the circuit is well designed, there will be no danger under normal conditions of use. Additionally, large capacity power banks, such as 10,000 mAh, haveof several batteries connected in parallel, which increases the risk. Power banks using soft batteries may burn under extreme circumstances but will not explode, but batteries using 18650 may explode under extreme circumstances. Extreme conditions include violent collisions, flat tires and overheating. Lithium battery products should be kept away from heat sources as much as possible. The normal operating temperature is 0-60℃ and the charging temperature is 0-45℃.