The Six Core Components of Lithium Polymer Batteries

The stable operation and safety assurance of lithium polymer batteries depend on the synergistic effect of multiple core components. 

These components include both "core components" that realize energy storage and conversion, and "protective components" that ensure 

safety. Specifically, they can be summarized into the following six parts:

1.Cathode:

The cathode is the core of the battery for storing energy. It realizes the release and reception of lithium ions through the redox reaction of 

materials, directly affecting the voltage and energy density of the battery.

Core materials: Lithium cobalt oxide, ternary materials (nickel-cobalt-manganese / nickel-cobalt-aluminum), lithium iron phosphate, etc., 

which are coated on aluminum foil current collectors to form electrode sheets.

Key role: It releases lithium ions during charging and receives lithium ions during discharging, being the source of the battery's "power output".

2.Anode:

The anode is responsible for accepting and storing lithium ions migrating from the cathode during charging, and sending them back to the 

cathode during discharging. Its performance affects the cycle life and fast-charging capability of the battery.

Core materials: Graphite is the mainstream (low cost and good stability). New materials such as silicon-based and lithium titanate are 

gradually being applied (to improve capacity and fast charging), which are coated on copper foil current collectors to form electrode sheets.

Key role: It stably embeds lithium ions to avoid structural collapse, being crucial for the battery's "energy reserve".

3.Electrolyte:

The electrolyte is the medium for the migration of lithium ions between the cathode and anode, and at the same time isolates electron 

conduction (to prevent short circuits). It is one of the core features that distinguish lithium polymer batteries from traditional liquid batteries.

Form and materials: It is mainly solid or gel polymer electrolytes (such as polymer matrices like polyethylene oxide and polyacrylonitrile + 

lithium salts), with no risk of leakage, improving safety and flexibility.

Key role: It ensures efficient conduction of lithium ions, serving as the "bridge" for the charge-discharge cycle of the battery.

4.Separator:

The separator is located between the cathode and anode, being the core component to prevent short circuits, and it also needs to allow 

lithium ions to pass through.

Materials and characteristics: Most are polymer porous films (such as polyethylene PE, polypropylene PP, or composite films), with uniform 

pore size, high temperature resistance, and mechanical strength. At high temperatures, it can block ion conduction through "pore closing" to 

prevent thermal runaway.

Key role: It physically separates the cathode and anode and only allows lithium ions to pass through, being the first line of defense for the 

battery to "prevent short circuits".

5.Housing:

The housing not only protects internal components but also determines the shape and sealing of the battery. Different from the metal hard 

shells of liquid batteries, the housing of lithium polymer batteries focuses more on lightweight and flexibility.

Materials: The mainstream is aluminum-plastic composite film, which is thin, lightweight, and has good flexibility, adapting to special-shaped 

designs (such as curved surfaces and thin sheets). It also blocks moisture and oxygen to prevent electrolyte deterioration.

Key role: It protects the internal structure, maintains the battery shape, and ensures sealing.

6.Protection Board:

The protection board is an indispensable "safety protection system" for the battery, especially for the chemical sensitivity of lithium polymer 

batteries. It is the core to avoid overcharging, over-discharging, overcurrent, and short circuits.

Core functions: It monitors voltage, current, and temperature in real-time through the control IC chip. When exceeding the safety threshold 

(such as voltage > 4.25V, < 2.5V, or excessive current), it triggers the MOS tube to cut off the circuit, and in extreme cases, protects through 

fuse blowing.

Key role: It prevents battery bulging, fire, and permanent capacity loss, serving as the last line of defense for the "safe operation" of the battery.

Summary: Synergy and core value of each part

These six parts work together to form a complete energy conversion and safety protection system: the cathode and anode determine energy 

density and capacity; the electrolyte and separator ensure ion conduction and physical isolation; the housing provides shape and protection; 

and the protection board guards the safety boundary of the entire system. Whether it is consumer electronics, power batteries, or energy 

storage equipment, the performance matching of these parts directly determines the capacity, life, safety, and applicable scenarios of the battery.