The 46Φ cylindrical battery is gaining attention as a key technology driving innovation in EVs, thanks to its high energy density and fast charging speed. Here, we introduce Pro Si-young Choi and Pro Kyeong-sik Ha from 46Φ Technology Group, who are dedicated to securing differentiated technological capabilities. 

Q. Please introduce your responsibilities at your group.

Pro Si-young Choi) The 46Φ Technology Group develops processes to achieve the optimal performance of 46Φ cylindrical batteries and apply them to mass production. The Process Technology Part that I am involved in focuses on optimizing and standardizing the assembly process for these batteries and improving major chronic defects occurring in the process. I specifically handle the winding process, where I define key parameters for new methods, defect types, and defect occurrence mechanisms. Based on these findings, I work on stabilizing the entire winding process. 

Pro Kyeong-sik Ha) I am responsible for laser welding in the Process Technology Part. My main tasks include standardizing the regular mass production conditions for laser welding and establishing the initial welding trajectory and conditions.

[Pro Si-young Choi (left) is in charge of winding process and Pro Kyeong-sik Ha (right) is in charge of laser welding.]

Q. Why does the 46Φ Technology Group have specialists for each process?

Pro Si-young Choi) The 46Φ cylindrical battery is not just a larger cylindrical battery; its most significant difference is the adoption of the tabless structure. Unlike conventional cylindrical batteries, this new design eliminates tabs and connects the entire electrode directly to the current collector, thereby improving both charging and discharging speed and safety. For this, specialists from various processes work together as a team. 

The biggest advantage of this team composition is the ability to quickly exchange feedback between processes, enabling faster problem-solving. For example, when analyzing defect factors, quality engineers can provide feedback from an equipment perspective, while equipment engineers can also contribute from a quality perspective. This cross-functional collaboration greatly enhances efficiency and problem resolution. 

[SAMSUNG SDI's 46Φ cylindrical battery]

Q. What was the most challenging or memorable experience of your work?

Pro Si-young Choi) Since the winding process is significantly different from the traditional method used for cylindrical batteries, the standardizing process was quite challenging. There were no existing references, so it was difficult to develop new concepts and identify critical factors. However, this also provided an opportunity to explore various approaches. 

Pro Kyeong-sik Ha) Last summer, I frequently visited mass production equipment manufacturers to discuss and prepare for a new laser welding method. As a third-year employee, it was the first project I led on my own, so I worked even harder and felt deeply attached to it. However, when I later found out that this new project was scrapped, I was disappointed. Nevertheless, I came to understand that this change was part of a broader effort to reduce unnecessary costs and move in a batter direction, which helped me move on easily. 

[Pro Si-young Choi (left) and Pro Kyeong-sik Ha (right) are working at the Cheonan Factory]

Q. What mindset do you have when approaching your work? 

Pro Si-young Choi) Although the battery industry is going through a difficult period, we have not let this time go to waste. Instead, we have been preparing to meet customer needs. I believe that as long as we continue to give our best effort, time will eventually be on our side. 

Pro Kyeong-sik Ha) The 46Φ Technology Group functions like a logistics hub. Just as shipments from different locations are sorted, optimized, and delivered quickly, we gather and coordinate opinions from various departments and customer requirements to ensure successful mass production. When I imagine the cells we produce being incorporated into final products and shipped worldwide, it motivates me to perform my role even better.