Comparison of advantages and disadvantages of soft pack batteries

Lithium batteries can be divided into three packaging forms: cylindrical, square, and soft. Cylindrical and square batteries are packaged in steel and aluminum shells, respectively, while soft pack batteries use aluminum plastic film. Once internal problems occur, the soft pack battery will bulge from the weakest part of the battery surface, resulting in relatively high safety. Therefore, a soft pack battery refers to a battery that is coated with a polymer shell on the outer layer of a liquid lithium-ion battery.

Advantages of Soft Pack Batteries

(1) Good safety performance: The soft pack battery is structurally packaged with aluminum plastic film. When safety issues occur, the soft pack battery will generally burst and crack, unlike steel or aluminum shell battery cells that can explode.

(2) High energy density. At present, in the power battery industry, the average cell energy density of mass-produced ternary soft pack power batteries is 240-250Wh/kg, but the energy density of ternary square (hard shell) power batteries of the same material system is 210-230Wh/kg. It can be seen that the cell energy density of the ternary soft pack power battery is at least 5% higher than that of the hard shell battery, or even more.

(3) Lightweight: Soft pack batteries are 40% lighter than steel shell lithium batteries of the same capacity and 20% lighter than aluminum shell lithium batteries. Low internal resistance: The internal resistance of soft pack batteries is smaller than that of lithium batteries, which can greatly reduce the battery's self consumption.

(4) The internal resistance of the battery is smaller. Due to its small internal resistance, ternary soft pack power batteries can greatly reduce battery self consumption, improve battery rate performance, generate less heat, and have a longer cycle life.

(5) Flexible design: The appearance can be changed to any shape, and it can be thinner. It can be customized according to customer needs, and new battery cell models can be developed


Disadvantages of Soft Pack Batteries
(1) Compared to hard pack batteries, soft pack batteries are not popular in the domestic market due to incomplete supply chains. The procurement channels for some raw materials and production equipment are still relatively single. Once suppliers encounter problems, it will have a certain impact on the production and operation of battery companies, as well as the supply stability of car companies.

(2) Low group efficiency due to the insufficient structural strength of the soft pack battery. When grouping, the soft pack battery is too soft, so many plastic brackets need to be installed outside the battery cells to enhance its strength. However, this method is a waste of space, and the efficiency of battery grouping is also relatively low.

(3) Due to the limitation of aluminum plastic film, the thickness of the battery cells in a soft pack cannot be too large, so it can only be compensated for in terms of length and width. However, cells that are too long and too wide are difficult to fit into the battery pack. Currently, the length of the soft pack cells can reach the limit of 500-600mm.

Guangzhou Battsys Co., Ltd (NEEQ:837375), was founded in 2006, which is a join-stock high-tech enterprise engaging in ODM and OEM , specially for customized and diverse research&production of lithium-ion battery，BATTSYS annual production capacity is tens of millions battery cells. The products are exported to dozens of countries & regions such as Europe, America & Asia etc.