Power Lithium Battery 502065 3.7V 700mAh Rechargeable Battery Cell For Smart Watch

 
Application:
 
1. Smartphones: Lithium polymer batteries provide high energy density for smartphones, allowing them to have longer battery life in a smaller size. Their thin, light and customizable features also meet the needs of mobile phones for thinner designs.
 
2. Tablets: They meet the requirements of tablets for battery capacity and portability, and support long-term use of devices.
 
3. Laptops: Compared with traditional batteries, they can provide higher energy, extend the use time of laptops, and also help to make computers thinner.
 
4. Bluetooth headsets: The compact lithium polymer battery provides long-lasting power support for the wireless use of Bluetooth headsets.
 
5. Smart watches and bracelets: Due to their customizable shapes, they can be well adapted to the designs of various smart wearable devices and ensure a certain battery life.

Difference for lithium polymer battery & li-ion battery cell:

In the fields of portable electronic devices, electric vehicles and energy storage systems, lithium-ion batteries and lithium polymer batteries are two mainstream energy storage solutions. Although both use lithium as the core chemical carrier, there are significant differences in material structure, performance and application scenarios. This article will analyze the technical principles, physical properties, safety performance and cost-effectiveness to reveal the technical division and development direction of the two batteries.

1. The essential difference between electrolyte morphology and structural design:

Lithium-ion batteries use a liquid electrolyte system, and their positive and negative electrode materials achieve ion conduction through lithium salts immersed in organic solvents. The typical structure includes multi-layer wound electrode sheets and metal shell packaging. This design gives it high structural stability, but also limits the freedom of shape. In contrast, lithium polymer batteries use solid or gel polymer electrolytes instead of traditional liquid electrolytes, and the electrode layers and diaphragms can be stacked in a planar manner through a lamination process. This structural characteristic enables it to have a customizable appearance, which can adapt to ultra-thin, curved or irregular installation spaces, and shows unique advantages in the field of smart wearable devices.

2. Performance game between energy density and power output:

In terms of energy density, lithium polymer batteries have improved their energy density per unit volume by about 10%-15% compared with traditional lithium ion batteries by optimizing electrode composite materials and packaging processes. This is mainly due to the higher tolerance of polymer systems to active substances and more compact internal space utilization. However, the liquid electrolyte system still has an advantage in ion conduction rate, which makes lithium ion batteries have better power output characteristics in high current discharge scenarios. Experimental data show that under 3C rate discharge conditions, the capacity retention rate of lithium ion batteries is 8%-12% higher than that of lithium polymer batteries, which makes them more suitable for the field of power tools that require instantaneous high power output.

3. Safety mechanism and thermal runaway prevention:

Safety is the core consideration of the evolution of battery technology. The solid electrolyte system of lithium polymer batteries significantly reduces the risk of electrolyte leakage, and its aluminum-plastic film soft packaging structure is more likely to achieve pressure release through local bulging when mechanically damaged, rather than explosive rupture. However, the polymer system has the risk of thermoplastic deformation under high temperature conditions, and it is necessary to improve the structure through additives to maintain structural stability. Although the steel shell packaging of lithium-ion batteries can provide stronger physical protection, it may cause a violent chain reaction when the internal short circuit occurs, which puts higher requirements on the temperature control accuracy of the battery management system (BMS).

4. Manufacturing process and cost structure analysis:

In terms of production process, the winding process and automated production line of lithium-ion batteries are highly mature, and the scale effect keeps their unit cost at a low level. However, the stacking process of lithium polymer batteries requires higher precision, and the stacking alignment error needs to be controlled within ±0.1mm, resulting in technical bottlenecks in improving the yield rate. The material cost structure shows that the price of polymer electrolytes is about 30% higher than that of liquid electrolytes, but the cost of aluminum-plastic film packaging is only 60% of that of metal shells. This increase and decrease in cost structure has led to a differentiated competitive landscape for the two types of batteries in the field of consumer electronics.

5. Application scenarios and market positioning:

Lithium-ion batteries dominate the electric vehicle power battery market with their mature industrial chain and cost advantages. Their standardized sizes (such as 18650, 21700) and modular design facilitate large-scale integration and cascade utilization. Lithium polymer batteries dominate the consumer electronics sector, with smartphones, true wireless headphones and other products strongly relying on their thin and light features. It is worth noting that with the breakthrough of solid-state battery technology, lithium polymer systems are gradually penetrating into the electric vehicle sector, while lithium-ion batteries are also improving their energy density through material innovations such as silicon-carbon negative electrodes, and the two technology routes are showing a trend of integration.
 

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