Difference Between Li-ion And Li-ion Polymer Battery

Which is better between Li-ion battery and Li-ion polymer battery?

Li-ion polymer batteries offer a slightly higher specific energy than what is offered by the traditional Li-ion batteries does. Moreover, LiPo batteries can be manufactured to be much thinner than Li-ion batteries. That made the LiPo batteries weight much less than the Li-ion ones, which in return made it more convenient to use in RC devices, laptops, and most of the electronic devices that require lightweight.

However, manufacturing costs for the LiPo batteries is higher than the manufacturing costs of the Li-ion batteries by around 10 to 30%.

What is the difference between Li-ion and Li-ion polymer battery?

Li-ion batteries

Lithium-ion batteries are made from what are called cells. Every cell of those is composed of three components; a positive electrode, a negative electrode, and a chemical component called an electrolyte between the positive and negative ones.

The positive electrode in the cell is designed from Lithium-Cobalt oxide. The negative electrode is designed from graphite. The electrolytes are such as oxides and sulfides. The electrolyte must have a long shelf life and offer high mobility for Lithium ions. The electrolyte can be liquid, polymer, and solid-state ones.

Li-ion Polymer batteries

Li-ion polymer batteries have the same exact build-up setup as the Li-ion batteries. The only difference is that in the Li-ion polymer batteries a microporous electrolyte is used instead of the conventional porous separator. Moreover, Li-ion polymer batteries are contained in a flexible polymer casing, unlike the Li-ion batteries where they are contained in a plastic casing.

Performance-wise

All Lithium-based batteries (Li-ion and Li-ion polymer) have the same working mechanism. When the battery is being charged, the Lithium-cobalt oxide "the positive electrode", gives some of its lithium ions, these ions move throughout the electrolyte to the negative electrode "the graphite" and subside there. The battery during this process store energy. After the charging process and during discharging; the Lithium-ions move back across the electrolyte from the negative electrode to the positive once again, which in turn produces energy that powers up the device the battery is attached to.

Unlike conventional batteries, Lithium-ion batteries have built-in electronic controllers. These controllers regulate how the batteries charge and discharge. These controllers prevent overcharging and overheating that can cause Lithium-ion batteries to explode in some cases.

During the charging and discharging process in the Lithium-ion batteries, electrons flow in the opposite direction of the movement of the ions around the outer circuit. It is important to note that electrons do not flow throughout the electrolyte itself. The electrolyte is effectively an insulating barrier and it does not affect the movement of the electrons.

Ions movement throughout the electrolyte and electrons moving around the external circuit in the opposite direction are two interconnected processes. If either of these movements stops the other stops too. When the battery is completely discharged and ions stop moving through the electrolyte, the electrons stop moving at the same time through the outer circuit. That is why you lose power in your device.

Discharging happens at a large rate when the device powered by the Lithium-ion battery is on; however, discharge also occurs even when the device is powered off. That is one downside for the Lithium-ion batteries.

To summarize how Lithium-ion works, it is as follows:

• During charging, lithium ions flow from the positive electrode to the negative electrode throughout the electrolyte.

• Electrons also flow from the positive electrode to the negative electrode around the outer circuit.

• Electrons and ions combine together at the negative electrode and deposit lithium there.

• When no more ions are present to flow, the battery is then fully charged and ready to be used.

• During the discharging process, the ions flow back through the electrolyte. Flowing back from the negative electrode to the positive electrode. The electrons flow from the negative electrode to the positive one but throughout the outer circuit. This process is what provides power to your device.

• When all of the ions inside the battery are moved back, then the battery is completely discharged and it needs to recharge once again.

What is the application of Li-ion and Li-ion polymer battery?

Li-ion batteries

All implantable medical devices including pacemakers use Lithium-ion batteries that are specifically designed for them. They are called Lithium-iodide batteries. These types of Li-ion batteries are designed to last up to 15 years or even more according to the type of work, they will be performing.

Since Lithium-ion, batteries provide its users with a long lifespan. Many watch manufacturers are now using them in their watches. Instead of conventional batteries, they start to use 3-volt lithium-ion batteries. Moreover, all smartwatches have Lithium-ion batteries inside. With capacities that can provide up to 45 days of running in some cases.

Li-ion polymer batteries

LiPo batteries are lightweight and can be made in almost any shape and size. They have large capacities and can hold large charges in small packages. Moreover, they are good at marinating constant voltage as they discharge.

LiPo batteries are used on a very large scale. They are used in RC devices, including boats, drones, helicopters, cars, and any other devices that require their battery to be lightweight. They are also used in many electronics devices especially smartphones.

Up until this moment, LiPo batteries have the largest market share of any batteries there is on market, and we can say that there is almost no tech company that does not use them in at least one of their products.

They are used in all Personal Digital Assistants (PDAs) and Smartphones. There are now smartphones that can last up to two days of on-screen time. That is thanks to the huge development of Li-ion technology during the past decade.

Moreover, there is no digital camera today on the market that does not have a Li-ion polymer battery in it. Either a removable one or embedded one. The usage of Lithium-ion polymer batteries in digital cameras has increased the number of photos that can be taken between every charge dramatically. The same thing goes for Audio devices and recorders, nowadays sound engineers can record and enhance the sound in video conferences and concerts using portable audio devices that can last up to 10 hours of continuous usage.