What is a soft-pack lithium battery, and its advantages and disadvantages

What is a soft-pack lithium battery? I believe many friends don't know it, so let's take a look at the soft-pack lithium battery manufacturer CSIT: "What is a soft-pack lithium battery, its characteristics and advantages and disadvantages".

What is a soft-pack lithium battery?

A soft-pack lithium battery is a liquid lithium-ion battery case with a polymer shell. The structure uses an aluminum-plastic film packaging design to protect the internal battery material. Soft-pack lithium batteries have the characteristics of high power density, strong safety, flexible spatial layout, good lightweight, and long cycle life.

Soft-pack lithium battery structure: positive and negative electrodes, electrolytes, diaphragms and their shells.

Positive electrode: A carbon electrode that absorbs and stores lithium ions is selected. When discharging, lithium becomes lithium ions, detaches from the battery anode, and reaches the cathode of the lithium-ion battery.

Negative electrode: The material selects an embeddable lithium compound with a potential as close to the lithium potential as possible, such as various carbon materials including natural graphite, synthetic graphite, carbon fiber, mesophase spherical carbon, etc. and metal oxides.

Electrolyte: A mixed solvent management system of ethylene carbonate, propylene carbonate and low-viscosity diethyl carbonate and other alkyl carbonates of LiPF6 is selected.

Diaphragm: Polyolefin microporous membranes such as PE, PP or their composite membranes are selected, especially PP/PE/PP three-layer diaphragms, which not only have a relatively low melting point, but also have high puncture resistance and also play a role of thermal insurance.

Shell: Steel or aluminum materials are selected, and the cover assembly has the main function of explosion-proof power-off.

Features of soft-pack lithium batteries:

Feature 1 of soft-pack lithium batteries: Good safety performance

Soft-pack batteries are structurally packaged with aluminum-plastic film. When unsafe factors occur, the soft-pack batteries will only bulge and crack at most, and will not explode like steel-shell aluminum-shell batteries.

Feature 2 of soft-pack lithium batteries: Light weight

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

Soft-pack lithium battery characteristic three: large capacity

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

Soft-pack lithium battery characteristic four: small internal resistance

The internal resistance of soft-pack batteries is relatively small. At present, the internal resistance of domestic soft-pack battery cells can be as low as 35mΩ, which greatly reduces the self-consumption of batteries.

Soft-pack lithium battery characteristic five: flexible design

The shape of soft-pack batteries can be customized according to customer needs, and new battery cell models can be launched.

However, there are relatively few soft-pack battery cell models for soft-pack lithium batteries at this stage, which cannot meet market demand; at the same time, the cost of launching new models is relatively high.

Advantages of soft-pack lithium batteries

High safety: By adopting a multi-layer aluminum-plastic film packaging design, soft-pack lithium-ion batteries can effectively prevent electrolyte leakage, fire or explosion inside the battery when internal short circuit, overcharge or over-discharge occur, thereby improving the safety of the battery. High power density: soft-pack lithium-ion batteries can be made thinner and lighter, so they can accommodate more electrolytes in the same volume, thereby increasing the energy density of the battery, resulting in the battery being able to store more abundant electrical energy.

Long cycle life: soft-pack lithium-ion batteries have a relatively long cycle life and can support more charge and discharge times, resulting in the battery being able to maintain high performance during long-term use.

Disadvantages of soft-pack lithium batteries:

High cost: The production process of soft-pack lithium-ion batteries is relatively complex and requires high-precision equipment and materials, so the manufacturing cost is relatively high.

The shell of the soft pack is relatively soft and easy to damage.

The above is the overall introduction of "What is a soft-pack lithium battery, the advantages and disadvantages of soft-pack lithium batteries" shared by soft-pack lithium battery manufacturer-CSIT. CSIT covers a total area of 66,000 square meters, with an annual output of 2.5Gwh battery cell manufacturing and 5Gwh battery packs and energy storage products. If you need customized consultation on soft-pack lithium batteries, please contact us: sales01@csit-energy.com