EV Battery

World Top Premium Steel in the Future Mega Trend

Neo Mobility

POSCO helps shape the future of cars to be safer and more eco-friendly.

Cars that are lighter and safer based on Giga Steel, electric steel plates, anode and cathode.
These are some of the things that we can provide for the cars of the future.

EV Battery

In a motor vehicle, the battery stores electricity in the form of a chemical reaction and converts the reaction back to electricity. An electric vehicle battery typically consists of a cell, a module and a pack. Multiple battery cells constitute a module, and multiple modules constitute a pack. An electric vehicle contains one such pack.

Battery Pack. A status of two modules or more than two modules connected in a linear or a parallel way.
Module. A status of two cells or more than two cells connected on a linear or a parallel way.
single Cell. A cumulative status of a single or multiple basic cells in a case, with the rolled or piled shape.
Basic Cell. A secondary battery which consists of anode, cathode, electrolyte and a membrane.

Basic Cell

Positive and negative active materials that generate electricity

A basic cell is the lowest unit that constitutes a battery consisting of a cathode, an anode, electrolyte and a separator. POSCO’s positive and negative active materials are used for this application.The positive active material is used for the cathode of a battery, and the most important element of the material is lithium. POSCO ESM has been offering PG-NCM, the most stable positive active material in the world, since 2017.

The negative active material stores lithium from the positive active material and then discharges it to generate electricity. Graphite is the most extensively used negative active material thanks to its ability to ensure a stable structure throughout repeated charging and discharging. As of 2018, POSCO Chemtech is the only producer of negative active material in Korea.

* PG-NCM: POSCO Gradient-Ni-Co-M, a highly stable positive active material: This innovative material can ensure good battery capacity and stability by gradually changing the chemical elements from the core to the surface.

Stainless steel that can prevent battery ignition and explosion

A battery module contains a bundle of cells in a frame to protect them from external impact, heat or vibration. It is another common application for POSCO’s stainless steel. With a high melting point, the stainless steel used for module cases can prevent the potential of the battery’s explosion. It is also highly resistant to corrosion, defying rust.

Comparison of aluminum and stainless steel

알루미늄(3000 series), 스테인리스강 (STS304 3/4H) 비교
	Aluminum (3000 series)	Stainless steel (STS304 3/4H)
Lightweight	3.2kg (12EA cell) → 0.27 kg/cell	1.32kg (12EA cell) → 0.11 kg/cell
Melting point	About 660℃	About 1450℃
Grade of strength	Material that withstands 20kg in area of ??1mm²	Material that withstands 100kg in area of ??1mm²
Weldability	Low	Excellent

Related Products: Austenitic series(300 series)

GIGA steel makes it light and safe

POSCO high-strength steel and GIGA steel are applied to various modules equipped with various control and protection systems. ‘GIGA steel’ is the steel sheet capable of withstanding more than 100kg per its area of 1mm² without rupture. The load corresponds to 10t exerted on a cross section of penny size. GIGA steel is applied for protecting the battery cell during the car accident. Also, the mileage of the electric car is able to be enhanced by reducing the battery pack weight, through applying GIGA steel.

Favorable battery pack condition

Heat radiation characteristic should be excellent, for emitting the heat towards outside.
Battery pack case should be durable, so that the cell module is protected during the car accident.
Battery pack should be able to be used for a long period while driving, without deformation or deterioration.

Related Products: Advanced High Strength Steel(CR)

How Does a Lithium Battery Work

A battery consists of a cathode, anode, electrolyte and separator. First of all, the cathode and the anode are where the electrons are, and the electrolyte is a media through which electrons move. The separator isolates the cathode from the anode. When the battery is connected to a power source, electrons start to move from the anode to the cathode. This process is called charging. When the two poles are connected for power use, the electrons start to move back from the cathode to the anode. This process is called discharging.