Comparison between soft pack lithium-ion batteries and cylindrical lithium-ion batteries?

Comparison between soft pack lithium-ion batteries and cylindrical lithium-ion batteries?

1、 Soft pack lithium-ion battery

Soft pack lithium-ion batteries are liquid lithium-ion batteries covered with a polymer shell. The difference from other batteries lies in the soft packaging material (aluminum-plastic composite film), which is also the most critical and technically challenging material in soft pack lithium-ion batteries. Flexible packaging materials are usually divided into three layers, namely the outer barrier layer (usually composed of nylon bOPA or PET as the outer protective layer), the barrier layer (middle layer aluminum foil), and the inner layer (multifunctional high barrier layer).

The packaging material and structure of soft pack lithium-ion batteries give them a series of advantages, including:

1. Good safety performance

Soft pack lithium-ion batteries are structurally packaged with aluminum-plastic film. In the event of safety hazards, soft pack batteries will only burst and crack, unlike steel shell aluminum shell cells that may explode.

2. Lightweight

Soft pack lithium-ion batteries are 40% lighter than steel shell lithium-ion batteries of the same capacity and 20% lighter than aluminum shell batteries.

3. Large capacity

Soft pack batteries have a capacity 10-15% higher than steel shell batteries of the same size, and 5-10% higher than aluminum shell batteries.

4. Low internal resistance

The internal resistance of soft pack batteries is relatively small. Currently, the minimum internal resistance of domestic soft pack battery cells can reach below 35mQ, greatly reducing the battery's self consumption.

5. Flexible design

The shape of the soft pack battery can be customized according to customer needs, and new battery cell models can be developed, especially in terms of external shape. Various irregularly shaped batteries can be customized, which can well meet the current needs of intelligent wearable electronic devices.

The characteristics of cylindrical lithium-ion batteries:

1. Has a higher weight to energy ratio and volume to energy ratio;

2. The voltage is high, and the voltage of a single lithium-ion battery is 4.2V,

3. The most prominent advantage of this battery is that it can be stored for a long time due to its small self discharge capacity;

4. No memory effect. Lithium ion batteries do not have the so-called memory effect of nickel cadmium batteries, so they do not need to be discharged before charging;

5. Long lifespan. Under normal working conditions, the number of charge/discharge cycles for lithium-ion batteries is much greater than 500;

6. It can be charged quickly. Lithium ion batteries can usually be charged with a current of 0.5-1 times the capacity, reducing the charging time to 1-2 hours;

7. Can be used in parallel at will;

8. Due to the absence of heavy metal elements such as cadmium, lead, and mercury in batteries, they are environmentally friendly and are considered contemporary green batteries;

9. High cost. Compared to other rechargeable batteries, lithium-ion batteries are more expensive.