13 advantages of Lithium polymer battery

Please see the analysis of the advantages of Lithium polymer battery. There are many classifications of lithium batteries, such as ternary materials, lithium iron phosphate materials, lithium ions, Fe2(MnO4)3, polymer lithium batteries and other types. So which is better, lithium-ion battery or polymer lithium battery?

With the continuous improvement of high technology and the continuous demand for energy saving and environmental protection, more and more energy-saving and environmental protection products have been applied to the market. As far as the battery market is concerned, lithium batteries are rapidly replacing traditional lead-acid batteries with various advantages. Batteries have become the main force in the energy storage market.

Introduction to lithium-ion batteries

It 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⁺ detaches from the positive electrode and intercalates into the negative electrode through the electrolyte, and the negative electrode is in a lithium-rich state; the opposite is true during discharge.

The application prospect of lithium-ion batteries is very broad. At present, they are mainly used in mobile phones and notebook computers, and they are the representatives of modern high-performance batteries.

Lithium battery classification

According to the different electrolyte materials used in lithium-ion batteries, lithium-ion batteries are divided into liquid lithium-ion batteries (Liquified Lithium-Ion Battery, referred to as LIB) and polymer lithium-ion batteries (Polymer Lithium-Ion Battery, referred to as PLB) or plastic lithium-ion batteries. Ion batteries (Plastic Lithium Ion Batteries, referred to as PLB).

The difference between lithium polymer battery and lithium ion battery

The positive and negative electrode materials used in polymer lithium-ion batteries are the same as liquid lithium ions. The positive electrode materials are divided into LiCoO₂, LiMn2O4, ternary materials and lithium iron phosphate materials. The negative electrode is graphite, and the working principle of the battery is also unanimous.

The main difference between them is 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”. At present, most of them use polymer gel electrolytes. 

13 Advantages of Lithium polymer battery

Lithium polymer battery is an upgraded product of lithium ion battery. Compared with the current popular lithium-ion batteries, it has the advantages of large capacity, small size (thin), and safety (will not explode). However, because the replacement of the entire industry chain takes a certain amount of time, its cost (cost) is still relatively high at present, and it is only used in high-end digital products (ultra-thin notebook computers, etc.). 

The main advantages of lithium polymer battery are as follows:

1. Higher Voltages

1. The operating voltage of a single lithium polymer battery 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. Higher Capacity Density

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

3. Lower self-discharge

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

4. Long cycle life

The lithium polymer battery has a long service life, and its cycle life can reach thousands times under normal use. 

5. No memory effect

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

Polymer lithium batteries adopt aluminum-plastic flexible packaging in structure, which is different from the metal casing of liquid batteries. Once a safety hazard occurs, liquid batteries are prone to explosion, while polymer batteries will only swell at most.

7. Small thickness

The thickness is small and can be made thinner, The lithium-polymer battery is so thin that the battery can be assembled into a credit card. Ordinary liquid lithium batteries adopt 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 3 or 6mm. This problem does not exist for polymer batteries, and the thickness can be less than 1mm, which meets the needs of current mobile phones.

8. Light weight

Lithium polymer battery use polymer electrolyte batteries without a metal case as a protective outer packaging. Polymer batteries are 40% lighter than steel-cased lithium batteries with the same capacity and specifications, and 20% lighter than aluminum-cased batteries.

9. Large capacity

Polymer lithium batteries have a capacity 10-15% higher than steel-cased batteries of the same size and specifications, and 5-10% higher than aluminum-cased batteries. Polymer lithium batteries have become the first choice for color screen mobile phones and MMS mobile phones. Most of the new color screen and MMS mobile phones on the market now use 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 lower than 35mΩ, which greatly reduces the self-consumption of batteries and prolongs the standby time of mobile phones. Can reach the level of international standards. This kind of 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 NiMH batteries.

11. The shape can be customized

Manufacturers are not limited to standard form factors and can be economically made to size. Polymer lithium battery can increase or decrease the thickness of the cell according to the needs of customers, develop new cell models, the price is cheap, the mold opening time is short, Some can even be customized according to the shape of the mobile phone to make full use of the space of the battery case and increase the battery capacity.

12. Good discharge characteristics

Lithium Polymer battery use colloidal electrolytes. Compared with liquid electrolytes, colloidal electrolytes have stable discharge characteristics and a higher discharge platform.

13. Simple protection board

The design of the protection board is simple, Due to the use of polymer materials, polymer lithium battery cells do not ignite or explode, and the battery itself is sufficiently safe. Therefore, the protection circuit design of Lithium polymer battery can consider omitting PTC and fuses, thereby saving battery costs.