One of the differences between pouch cell batteries and other batteries is the material of the casing. Cylindrical batteries have a hard casing, which are made of nickel and steel or aluminum alloy.
A pouch cell on the other hand consists of many types of layers to form a multilayer film consisting of an outer layer, middle layer, and an inner layer.
Outer layer consists of nylon, middle layer contains an aluminum foil, and in the inner layer – a heat sealing layer, which allows for better heat dissipation.
There are four distinct advantages for a pouch cell compared to cylindrical batteries.
Advantage 1: They’re Safer
Firstly, it has a very high barrier property; secondly, it has a good heat sealing property; thirdly, the material is resistant to electrolyte and strong acid corrosion; it also has good ductility, flexibility and mechanical strength, and this advantage makes the pouch cell battery safer.
When a safety hazard occurs, the pouch cell battery will only swell and crack at most. Unlike the steel shell battery where a sudden explosion phenomenon might occur.
Advantage 2: Better space utilization
The pouch cell’s exterior is flexible thus making the most efficient use of space and can reach a packaging efficiency of 90-95%, which is unreachable by other types of casing. The flexibility will allow the external case to form to the battery, rather than the other way around.
Advantage 3: Higher energy density
Eliminating the metal case can reduce weight. In terms of weight, a pouch cell battery of equivalent capacity is 40% lighter than a nickel-steel cased lithium battery and 20% lighter than an aluminum-cased battery. In terms of energy density, pouch cell batteries of the same size are usually 10-15% higher than steel-cased batteries and 5-10% higher than aluminum-cased batteries.
Advantage 4: Customizable
Pouch cell batteries can be custom designed according to the specific requests of the customer. With their soft exterior and ability to be reshaped and sized, custom designed packs can be formed to meet all challenges.