Electric Vehicle Batteries Are Not Just One?... Battery Industry Shifts to 'Pack' Competition

[Asia Economy Reporter Hwang Yoon-joo] Along with the rapid growth of the electric vehicle (EV) market, interest in batteries is also increasing. When reading articles about EV batteries, terms such as 'Cell', 'Module', and 'Pack' can be seen. All refer to batteries, but each has a different role. Especially, while battery manufacturers have focused on extending the driving range of the 'Cell' until now, the recent trend in battery development is shifting towards the 'Pack'.

The heart of an electric vehicle, the battery, is broadly divided into 'Cell', 'Module', and 'Pack'. If you disassemble an EV, the first large battery you encounter is the 'Pack'. Inside the pack, there are 'Modules', and within those are the 'Cells', which are commonly referred to as batteries.

From the perspective of battery manufacturers, the battery 'Cell' undergoes two transformations to become a 'Pack', which is then installed in the vehicle. When people talk about batteries, they usually mean the single battery unit, the 'Cell'.

The 'one-charge driving range', which is the biggest factor consumers consider when purchasing an EV, is closely related to the 'Cell'. The basic unit of the battery, the 'Cell', must have a high capacity per unit volume (or weight) to maximize performance within the limited space inside the vehicle. This is called 'energy density' per volume (or weight).

Consequently, battery manufacturers have focused on developing 'high-energy-density cells' that can store more energy in the same volume or weight. They are developing 'high-nickel (High Ni)' cathodes by increasing the nickel content in the cathode, which is the core material of the 'Cell', and are also adding silicon or increasing its content in the anode material, which was traditionally graphite.

To safely and efficiently manage these numerous battery 'Cells', 12 to as many as 48 'Cells' are grouped together to form a 'Module'. Multiple modules are then assembled into a 'Pack', and the number of 'Cells' and 'Modules' varies according to customer specifications. For example, the BMW i3 is equipped with a total of 96 'Cells'. Twelve 'Cells' are grouped into one 'Module', and eight 'Modules' are assembled into a 'Pack'. The number of 'Cells' and 'Modules' differs for each EV model produced by automakers such as Hyundai, Kia, and Volkswagen.

While battery manufacturers have focused on the performance of the 'Cell' until now, they are now also considering how to design and configure the 'Module' and 'Pack' more efficiently.

The battery 'Module' is constructed with a robust frame to better protect the battery 'Cells' from external shocks such as heat and vibration. It is also equipped with a BMS (Battery Management System) that monitors the status of the 'Cells'.

The final form, the battery 'Pack', consists of multiple modules and includes a Master BMS that manages the temperature and voltage of the battery 'Cells' sent from the modules. It also houses cooling devices and various control systems.

Samsung SDI explained, "Since the efficiency of the 'Pack', which is ultimately installed in the EV, can affect the vehicle's performance and design, increasing the energy density of the 'Cell' is fundamental, but interest in developing the 'Module' and 'Pack' is also growing."

This content was produced with the assistance of AI translation services.