Lithium Polymer (Li-Po) vs Lithium Ion (Li-ion) Batteries: Differences and Which to Choose?
Lithium Polymer (Li-Po) vs Lithium Ion (Li-ion) Batteries
Lithium polymer (Li-Po) and lithium ion (Li-ion) batteries are two most confused products in rechargeable battery market.
Even though both are lithium-based, cell structure, packaging and discharge power are completely different.
Wrong battery selection causes swelling of your device, short life and safety risk.
Let's explain difference with engineer eye.What Is Li-ion Battery?Lithium ion batteries are metal-cased batteries, generally produced in cylindrical form. Most known example is 18650 batteries. Thanks to robust structure and long cycle life (500-1000 cycles), they are preferred in powerbank, flashlight and industrial devices.
You can find capacity suitable for your project with wide lithium ion battery varieties.What Is Li-Po Battery?Lithium polymer batteries are produced inside foil pouch.
Thanks to this, they can be produced ultra thin, light and in desired shape. They are indispensable for designs where space is limited such as drone, FPV, smartwatch and earphone. For applications requiring high current, lithium polymer battery models are most correct choice.
5 Critical Differences
1. Shape and Weight: Li-Po is thin and light, Li-ion is impact resistant. For wearable technology, Li-Po is advantageous.
2. Discharge Power (C-Rating): Most important difference! Drone and RC vehicles need 60C-100C current.
Only Li-Po gives this. Li-ion generally stays at 1C-2C.
3. Energy Density: Not every thin one is stronger. For correct comparison, mAh, Wh and weight should be calculated together.
4. Safety: Li-Po is prone to swelling in faulty charging. That's why it must be used with a quality battery protection and charging board.
5. Assembly: Batteries are not used alone. Especially for 18650 batteries, correct battery holder and holder selection prevents contact problems.
Which One Should You Choose?
Powerbank, UPS, Industrial System -> Li-ion / LiFePO4Drone, RC, FPV, Everything Requiring High Current -> Li-PoSmart watch, TWS Earphone, Thin Design -> Li-Po PouchDon't forget, when choosing battery, you should look not only at type; nominal voltage, capacity, discharge current and operating temperature. Wrong charging circuit creates safety risk.
Comparison Table
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