What is a semi-solid state battery?

What is a semi-solid state battery? What is the difference between lithium iron phosphate batteries and ternary lithium-ion batteries?

Batteries are crucial for our daily lives, but they come in many different types. Especially, various technologies are used for high-capacity batteries, such as batteries for electric vehicles and portable power sources. However, what are the characteristics, advantages, and disadvantages of each type of battery? In addition, under what circumstances are each type of battery used? In this article, we will provide a clear and easy to understand explanation of the differences between semi-solid state batteries, lithium iron phosphate batteries, and ternary lithium-ion batteries.

1. What is a semi-solid state battery?
Semisolid state battery is a new type of battery that combines the characteristics of solid and liquid electrolytes. It is mainly developed for lithium-ion batteries, characterized by high ion conductivity in the electrolyte. Semisolid state batteries, as a battery technology with high energy density, safety, long lifespan, and low environmental impact, are a very promising battery technology. Semi solid state batteries can be divided into three types: gel polymer type, clay type and liquid additive type.

1) Gel polymer type: flexible battery with gel electrolyte. Has good bending resistance and fast charging ability. Suitable for card and wearable devices.
2) Clay type: A battery similar to clay with electrolyte mixed in the electrode. Long service life, low risk of liquid leakage and fire. Suitable for solar power generation and automotive use.
3) Liquid filled type: A battery made of ceramic with a small amount of electrolyte soaked inside. Has high thermal stability and can be used at high temperatures. Suitable for the Internet of Things, industrial equipment, and automotive interiors.

Batteries are charged and discharged through the movement of ions between positive and negative electrodes, and their names vary depending on the type of ions. For example, lithium-ion batteries contain lithium in ionic form. The path of ion travel is called electrolyte, and lithium-ion batteries use liquid electrolyte, but this liquid is flammable and dangerous. Therefore, batteries using solid or gel electrolytes are being developed. These are called all solid state batteries or semi-solid state batteries. Making electrolyte into solid or gel can improve the safety of battery.

2. What is lithium iron phosphate battery?
Lithium iron phosphate battery is a lithium-ion battery that uses iron phosphate (LiFePO4) as the positive electrode. Iron phosphate is a cheap and stable substance with low risk of thermal runaway or ignition. Lithium iron phosphate batteries have a long lifespan and multiple charge and discharge cycles. In addition, as iron phosphate is not a rare metal, it can be said that its impact on the environment is relatively small.

3. What is a ternary lithium-ion battery?
A ternary lithium-ion battery is a type of lithium-ion battery that uses ternary compounds such as nickel cobalt manganese (NCM) or nickel cobalt aluminum (NCA) as the positive electrode. The ternary system has high energy density and relatively stable output even at low temperatures. However, its drawbacks include the high cost of using rare metal cobalt and the high risk of thermal runaway and ignition.

This table summarizes the advantages and disadvantages of semi-solid state batteries, lithium iron phosphate batteries, and ternary lithium-ion batteries.

Tags: #Semi solid state battery #Lithium iron phosphate battery #Ternary lithium-ion battery