Lithium polymer battery ( Li-polymer battery ), is a chemical battery. Compared with the previous battery, it has the characteristics of high energy, miniaturization and light weight. Lithium polymer batteries have ultra-thin features, and can be made into batteries of different shapes and capacities to meet the needs of some products. The theoretical minimum thickness can reach 0.5mm.

What's UL1642 certification? What's UL1642 standard for polymer lithium-ion battery? What's the test items of UL1642 certification?

Since the lithium-ion battery entered the market, it has been widely used due to its advantages such as long life, large specific capacity and no memory effect. Low-temperature use of lithium-ion batteries has problems such as low capacity, severe attenuation, poor cycle rate performance, obvious lithium evolution, and unbalanced lithium extraction. However, with the continuous expansion of application areas, the restrictions brought by the low-temperature performance of lithium-ion batteries have become more and more obvious.

Safety comparison of lithium cobaltate, lithium iron phosphate and polymer lithium batteries. Many customers have a lot of disputes about the safety performance of lithium batteries. Compared with lithium cobalt oxide batteries and polymer lithium batteries, the most obvious advantage of lithium iron phosphate batteries is the extremely high safety factor and support for fast charging (high current charging). And a wider operating temperature range.

The use of lithium batteries is restricted in low temperature environments. Except for the severe deterioration of discharge capacity, lithium batteries cannot be charged at low temperatures. During low-temperature charging, the intercalation of lithium ions on the graphite electrode of the battery and the lithium plating reaction coexist and compete with each other. Under low temperature conditions, the diffusion of lithium ions in graphite is inhibited, and the conductivity of the electrolyte decreases, resulting in a decrease in the intercalation rate and the lithium plating reaction on the graphite surface is more likely to occur. The main reasons for the decrease in the life of lithium-ion batteries when used at low temperatures are the increase in internal impedance and the degradation of the capacity due to the precipitation of lithium ions.