What is a polymer
Polymer battery is also called lithium polymer battery (Li-polymer), also known as high polymer lithium ion battery. It is also a kind of lithium-ion battery, but compared with liquid lithium-ion battery (Li-ion), it has many obvious advantages such as high energy density, miniaturization, ultra-thin, lightweight, and high safety, so it is a new type of battery. In the shape, lithium polymer battery has the characteristics of ultra-thin, can meet the needs of a variety of products, produced into any shape and capacity of the battery. The minimum thickness of such batteries can be up to 0.5mm. It has the same nominal voltage as Li-ion which is also a nominal voltage of 3.7V, no memory effect.
Principles of polymers
Polymer batteries work in the same way as liquid lithium, except that the electrolyte is different from liquid lithium. The important structure of a battery includes three elements: positive electrode, negative electrode and electrolyte. The so-called polymer lithium ion battery means that at least one or more of these three important structures use polymer materials as an important battery system. In the developed polymer lithium-ion battery system, the polymer material is mainly used in the positive electrode and electrolyte. Anode materials include conductive polymer or lithium ion batteries used in inorganic compounds commonly, use solid electrolyte or colloidal polymer electrolytes, or organic electrolyte, lithium ion technology commonly used liquid or gel electrolyte, so be strong secondary packaging for combustible, the active ingredient, this added weight, in addition also limits the size of flexibility. Lithium-ion polymer processes have no excess electrolyte, so they are more stable and less prone to dangerous conditions caused by battery overcharging, collision or other damage, and overuse.
The new generation of polymer lithium ion battery can be thin in shape (ATL battery can be as thin as 0.5 mm, the thickness of a card), arbitrary area and shape, which greatly improves the flexibility of the battery shape design, so as to meet the needs of the product, made into any shape and capacity of the battery. Provides application device developers with a high degree of design flexibility and adaptability in power solutions to maximize their product performance. At the same time, the unit energy of the polymer lithium-ion battery is 50% higher than that of the general lithium-ion battery, and its capacity, charge and discharge characteristics, safety, operating temperature range, cycle life (more than 500 times) and environmental performance have been greatly improved compared with the lithium-ion battery
Properties and uses of polymer
1. Restraining battery polarization, reducing thermal effect and improving magnification performance;
2. Reduce the internal resistance of the battery, and significantly reduce the increase of dynamic internal resistance in the cycle process;
3. Improve consistency and increase the cycle life of the battery;
4. Improve the adhesion force between the active substance and the collector, and reduce the manufacturing cost of the pole plate;
5. Protect the collector from corrosion by electrolyte; And lithium iron phosphate power lithium battery, cycle life of more than 2000 times, standard charging (5 hours rate) use, can reach 2000 times. The same quality of lead-acid battery is new half a year, old half a year, maintenance and maintenance for half a year, the most is 1~1.5 years, and the lithium-ion iron phosphate battery under the same conditions, the theoretical life will reach 7~8 years. Considering comprehensively, the performance price ratio is more than 4 times that of lead-acid battery in theory.
High current discharge can be high current 2C fast charge and discharge, in the special charger, 1.5C charging within 40 minutes can make the battery full, starting current up to 2C, but lead-acid battery does not have this performance.
3. Good high temperature performance
The electrothermal peak value of lithium iron phosphate can reach 350℃-500℃ while that of lithium manganese acid and lithium cobalt acid is only about 200℃. The operating temperature range is wide (-20C--75C), with high temperature resistance characteristics of lithium iron phosphate electric heating peak can reach 350℃-500℃ while lithium manganese acid and lithium cobalt acid only at about 200℃.
4. Large capacity
It has a larger capacity than ordinary batteries (lead acid, etc.). 5 ah ah - 1000 (monomer)
5. No memory effect
Rechargeable batteries can quickly fall below their rated capacity when they are constantly charged to the full, a phenomenon known as memory effect. Like nickel-metal hydride, nickel-cadmium batteries have memory, and lithium iron phosphate batteries do not have this phenomenon, no matter what state the battery is in, can be used with the charge, do not need to first put out and then charge.
6. Light weight
Lithium-ion iron phosphate batteries of the same size and capacity are two-thirds the volume and one-third the weight of lead-acid batteries.
7. The environmental protection
Lithium-ion iron phosphate battery is generally considered to do not contain any heavy metals and rare metals (NiMH batteries need rare metals), non-toxic (SGS certification), no pollution, in line with the European RoHS regulations, for the absolute green environmental protection battery certificate. Therefore, the lithium ion battery is optimistic about the industry, the important consideration is environmental protection, so the battery was included in the fifteenth period of the 863 national high-tech development plan, become the national key support and encourage the development of the project. With China's entry into the WTO, the export volume of China's electric bicycles will increase rapidly, and the electric bicycles entering Europe and the United States have been required to be equipped with non-polluting batteries.
6. Improve the high and low temperature performance of lithium iron phosphate battery, and improve the processing performance of lithium iron phosphate and lithium titanate materials.
