Li-ion Battery VS Li-Polymer Battery: What you need to Know

The batteries: Lithium-ion simply abbreviated as Li-ion and Lithium-Polymer abbreviated as Li-Po are two batteries that could be confusing sometimes. They bear the same parent name, Lithium which therefore sets in the confusion.

Their working principles also look alike and this makes it more difficult to understand where the difference lies. In this article, I have trashed out all that may be confusing about the two of them and also made clear points about what is it to know about the said batteries regarding their pros and cons.

LITHIUM-ION BATTERY

The Li-ion battery which could also be abbreviated as LIB is a rechargeable battery used in portable electronic devices like phones and laptops. It was developed in the 1980s and it has undergone a series of improvements since then.

In Li-ion batteries, intercalated lithium material is used as the positive electrode while graphite serves as the negative electrode. The electrolyte is usually non-stoichiometric liquid lithium salts.

Li-ion batteries have high energy density. This implies that good amount of energy could be stored in a small-sized Li-ion battery.

They do not have a memory effect and they have low self-discharge ability. When a battery has a memory effect, charging it will be a problem over time. It is best to properly discharge these types of batteries before they are recharged. Li-ion batteries are also relatively cheaper than Li-Po batteries.

On the negative side, Li-ion batteries have their disadvantages. They are unduly unstable and can result in an explosion. These batteries also have aging issues as they do not have a very long lifespan as some deep cycle batteries. Nevertheless, Li-ion batteries through its cutting-edge technologies, have very wide application in various industries.

LITHIUM POLYMER BATTERY

Funny enough, these batteries should be rightly called Lithium-Ion Polymer batteries. It is so because it is a rechargeable lithium-ion battery that uses the polymer electrolyte technology. In a common Li-ion battery the electrolyte is a liquid salt of lithium.

But in Li-Po the electrolyte is a high conductive semi-solid Polymer. Such polymers are Poly Methyl methacrylate (PMMA), polyethylene oxide, polyvinylidene fluoride and so on. Therefore the major difference between Li-ion and Li-Po lies in the different electrolytes used.

Li-Po has a higher specific energy (energy per unit mass) than a Li-ion battery. This type of battery is flexible. Hence this flexibility gives it the luxury of being formed into desirable shapes.

They are lightweighted and are best applied to areas where low weight is required like in aircrafts and boats. Since the electrolyte is a solid polymer, there is no risk of the electrolyte leaking out. Electrolyte leaking could be associated with Li-ion and other type of  batteries. LiPo batteries is associated with a low self-discharge rate.

LiPo batteries have some disadvantages, as every other battery type does. First, due to the relative higher cost of production, LiPo batteries are 10-30% more expensive than Li-ion batteries. One of the greatest setbacks associated with LiPo is that unlike Li-ion, they have low energy density and they also have a lower lifespan than Li-ion.

With all these stated about these batteries, which is better between Li-ion battery and Li-Po battery?

You must know that both batteries are the same but are differentiated by the nature of their electrolyte and packaging system. So both of them are good, but when it comes to energy per volume, Li-ion has it. They serve different purposes through their varying properties.