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The difference between polymer lithium ion battery and lithium polymer battery

2022-06-17
A lithium-ion battery is a secondary battery (rechargeable battery) that mainly relies on the movement of lithium ions between the positive and negative electrodes to work. During the discharge process, Li intercalates and deintercalates back and forth between the two electrodes; during charging, Li falls off from the positive electrode, intercalates into the negative electrode through the electrolyte, and the negative electrode is in a lithium-rich state; the opposite is true for TV. The application prospect of lithium-ion battery is very broad, and it is mainly used in mobile phones and notebook computers. It is the representative of modern high-performance batteries.

The difference between lithium polymer battery and lithium ion battery
The positive and negative materials used in polymer lithium-ion batteries are the same as liquid lithium ions. The positive materials are divided into lithium cobalt oxide, lithium manganate, ternary materials and lithium iron phosphate materials. The negative electrode is graphite, and the working principle of the battery is also basic. Consistent.

The main difference between them is the difference in the electrolyte. Liquid lithium-ion batteries use liquid electrolytes, while polymer lithium-ion batteries use solid polymer electrolytes instead. This polymer can be "dry" or "colloidal" Yes, polymer gel electrolytes are mostly used at present.

Lithium polymer battery or lithium ion battery which is better
Lithium polymer battery is an upgraded product of lithium ion battery. Compared with the popular lithium-ion battery, it has the advantages of large capacity, small size (thin), and safety (no explosion). However, because the replacement of the entire industry chain takes a certain amount of time, its cost (cost) is still relatively high, and it is only used in high-end digital products (ultra-thin notebook computers, etc.).

The advantages of lithium polymer batteries mainly include the following aspects:

1. The working voltage of the lithium polymer battery unit cell is as high as 3, 6v~3, 8v, which is much higher than the 1, 2V voltage of nickel-metal hydride and nickel-cadmium batteries.

2. The lithium polymer battery has a high capacity density, and its capacity density is 1, 5~2, 5 times that of a nickel-metal hydride battery or a nickel-cadmium battery, or higher.

3. The self-discharge of lithium polymer battery is small, and its capacity loss is also small after being placed for a long time.

4. The lithium polymer battery has a long life, and its cycle life can reach more than 500 times under normal use.

5. The lithium polymer battery has no memory effect, and it is not necessary to empty the remaining power before charging, which is convenient to use.

6. Good safety performance

The structure of polymer lithium battery adopts aluminum-plastic flexible packaging, which is different from the metal shell of liquid battery. In the event of a safety hazard, the liquid battery is easy to explode, while the polymer battery will only bulge at most.

7. Small thickness, can be made thinner

Lithium-polymer batteries are so thin that they can be assembled into credit cards. Ordinary liquid lithium batteries use the method of customizing the shell first, and then plugging the positive and negative materials. There is a technical bottleneck when the thickness is less than 3mm or 6mm. The polymer battery does not have this problem, and the thickness can be less than 1mm, which meets the needs of current mobile phones. direction.

8. Light weight

Lithium polymer batteries use polymer electrolyte batteries without metal shells as protective outer packaging. The weight of the polymer battery is 40% lighter than that of the steel case lithium battery with the same capacity specification, and 20% lighter than that of the aluminum case battery.

9. Large capacity

The capacity of polymer lithium battery is 10-15% higher than that of steel shell battery of the same size, and 5-10% higher than that of aluminum shell battery. Using polymer batteries.

10. Small internal resistance

The internal resistance of polymer lithium battery cells is smaller than that of ordinary liquid cells. At present, the internal resistance of domestic polymer cells can even be below 35mΩ, which greatly reduces the self-consumption of the battery and prolongs the standby time of the mobile phone. Can reach the level in line with international standards. This polymer lithium battery that supports large discharge current is an ideal choice for remote control models, and has become the most promising product to replace nickel-metal hydride batteries.