With the continuous development of portable power sources, lithium-ion batteries and lithium polymer batteries stand out among numerous batteries. From portable cameras, smart phones to drones,electric vehicles. These two types of lithium batteries play an important role in various electrical equipment.
We already know they all use Li to store energy, what’s the difference between lithium-ion battery and lithium polymer battery?How to choose the suitable type of lithium battery for your products?This article will introduce you to the characteristics, advantages, and disadvantages of two types of batteries in multiple dimensions in detail.
Development History
Lithium-ion Battery
In 1970, M.S.Whittingham from the Exxon company invented the first lithium-ion battery.Since then,many scholars are continually innovating in the field of lithium-ion battery.Until 1991, Sony successfully developed commercial lithium-ion battery.From then on, the era of lithium-ion commercialization began.
Lithium-ion batteries have very strong practicality. Greatly reduces the weight and volume of small electronic devices such as smartphones, laptops, and portable cameras. Extend the usage time at the same time.There is no heavy metal cadmium in the lithium-ion battery. So, compared with traditional nickel-cadmium batteries, it greatly reduces the pollution to the environment.
Lithium Polymer Battery
Although the lithium polymer battery was not commercialized until 1999 by Sony,the development lag of lithium-ion battery behind lithium polymer battery. In 2002, the 7% market share of lithium-ion batteries was occupied by lithium polymer batteries. In 2010,the market share of lithium polymer batteries increased to about 30%.
Because of the good characteristics,Europe, America, Japan and other regions have accelerated the progress of research and development.For example,Japan’s leading brands Sony, Panasonic had decided to produce lithium polymer batteries together. The full series products of Apple are using lithium polymer batteries now. Because lithium polymer batteries can be customized in a more flexible size,which makes the electronics smaller,thinner and lighter.
Structure
The materials of lithium-ion batteries and lithium polymer batteries are similar.
Lithium-ion Battery
Lithium-ion batteries were composed of 2 positive and negative electrodes. And separated by liquid electrolytes.The chemical composition limited the shape of lithium-ion batteries. Therefore, the shape of lithium-ion batteries is usually cylindrical or rectangular. Lithium-ion batteries usually need strong metal casing to prevent leakage.
Lithium Polymer Battery
Lithium polymer batteries were composed of positive and negative electrodes too.The charging and discharging process is similar to Lithium-ion batteries. But lithium polymer batteries use solid or gel electrolytes instead of liquid.These types of electrolytes can resist the risks of overcharge, discharge and short circuit perfectly.
Also lithium polymer batteries can offer a variety of shapes and sizes.Lithium polymer batteries can be very thin by production to suit various applications requiring specific shapes and capacities. The minimum thickness can reach 0.5 mm in theory.The polymer casing design reduces the chance of electrolyte leakage and thermal runaway.
Security and Durability
Lithium-ion batteries and lithium polymer batteries are very different in terms of security and durability.
Lithium-ion Battery
Because the liquid electrolytes have corrosive properties they need special treatment.So there is a certain risk of leakage. It has the risk of thermal runaway when the battery is overcharging, short circuit or physical damage That may cause explosion or fire.However,the situations above are rare because electronic controllers usually regulate the charge and discharge power to prevent the battery from overheating.
Lithium-ion Batteries are famous for their long service life.The cycle life of lithium-ion batteries is usually around 500-1000 times.Lithium-ion Batteries have low self-discharge rate and can maintain power longer.Lithium-ion Batteries don’t have memory effect.You don’t need to fully discharged and can charge at any time.Lithium-ion battery has standard models in mature production now,which makes its cost is cheaper.
Lithium Polymer Battery
The lithium polymer batteries usually use flexible materials to packing the batteries.Which can provide better mechanical stability, thereby reducing the possibility of physical damage or perforation.In addition,the solid or gel electrolytes have a low risk of leakage.Not easy to cause explosion.The security is higher.
The decay rate and self-discharge rate of lithium polymer batteries is almost the same as lithium ion batteries..
The cycle life of lithium polymer batteries is between 500 and 1000 times.You have to follow the specific store and use methods to keep the battery service life longer.For example,maintain balanced charging to avoid fully discharging.Lithium polymer batteries are good choices if your products require flexible size,light weight.
Energy Density and Capacity
Lithium-ion Battery
Usually the energy density of lithium-ion batteries is almost the same.(150-250 Wh/kg).That means it can store good energy at the same weight and volume.Lithium-ion batteries are very suitable for the equipment which needs long charging like smart phones and electric vehicles.
Lithium Polymer Battery
The energy density of lithium polymer batteries is lower(200-300 Wh/kg). That means it can store less energy at the same weight and volume compared with lithium-ion batteries .But can design a high capacity for specific applications.
Production Cost
Lithium-ion Battery
Since the commercialization of lithium-ion batteries to the present.The production process of lithium-ion batteries is already very mature. Also,the cost of liquid electrolytes is very cheap.Therefore,the overall production cost of lithium-ion batteries is lower.
Lithium Polymer Battery
The cost of solid or gel electrolytes itself is high.The production process of lithium polymer batteries is complex.Therefore,the overall production cost of lithium polymer batteries is higher.Lithium polymer battery is a better choice if you are producing equipment like drones and wearable devices have special requests about weight and shape.
Application Field
Because of the different characteristics between lithium-ion batteries and lithium polymer batteries.Their application areas are also different.
Lithium-ion Battery
Consumer Electronics
Smart phone, laptop and other portable electronic devices.Because lithium-ion batteries can store more power in a smaller space.
New Energy Vehicles
Lithium iron phosphate batteries used for electric bicycles and solar energy storage systems because of the security and long cycle life.Ternary lithium batteries are used in electric vehicles because they have higher energy density.
Lithium Polymer Battery
Because of its bendability and lightweight properties, lithium polymer batteries are very suitable for powering small electronic devices such as smart watches and wireless headphones.
IOT and GPS Tracker
The solid or gel electrolytes of lithium polymer batteries can improve low-temperature endurance.
Distinguish Between Lithium-ion Batteries and Lithium Polymer Batteries
You can identify which lithium battery type your device uses by checking its appearance, shape, label, and user manual.
Appearance and Shape
Lithium-ion batteries: Usually have a cylindrical or rectangular strong steel casing. Common cylindrical models include the 18650 and 21700.
Lithium polymer batteries: Typically use a flexible packaging design and have a variety of shapes and sizes. They are usually flat and covered in a soft-touch aluminum-plastic film.
Battery Labels and Markings
There always have labels and markings on the battery. The manufacturer always indicates the battery type and technical parameters.
User Manual
Check the battery user manual. These files always provide detailed information about the battery type, performance parameters, and intended use.You can effectively distinguish between lithium-ion and lithium polymer batteries by these methods. Please consult us for more information.
Conclusion
In summary, both lithium-ion batteries and lithium polymer batteries have their advantages and disadvantages.
Choosing which type of lithium batteries depends on your application needs, cost considerations, and safety requirements. If you want the cheaper cost ,longer life and high energy lithium batteries, choose lithium-ion batteries. If you require lightweight and flexible lithium battery devices, choose lithium polymer batteries.
If you’re unsure about which type to choose, contact us. We are a company that integrates R&D, design, production, and sales for many years in the high-tech battery industry. Our products have numerous national and international certifications, and we have extensive experience in the Li-ion battery field, making us your trusted battery partner.
