Jiang Jibing, Vice President of EVE Energy and Director of the Battery System Research Institute, was invited to attend the China Electric Vehicle 100 Forum (2025) and delivered a keynote speech on “OMNI All-Purpose Battery”.
A look at the 4 reasons why EVE believe in large cylindrical cells [2]:
- Standardization
- In-Situ Upgrades
- Zero Swelling
- Intrinsic Safety
Author: Woody Wu at power9tech.cn
Standardization
Perfectly Aligns with the Efficiency Requirements of the Automotive Industry
Large cylindrical batteries can achieve continuous efficiency improvements due to the standardization of manufacturing processes and system designs.
Here, we can see that the manufacturing efficiency of large cylindrical batteries at 300 PPM is 10 times that of prismatic cells, while our manufacturing steps have been further reduced to 10 steps, shortening the production cycle to 7 days.
In terms of system design, standardized components and modular assembly processes have enabled standardized battery configurations. This efficiency allows us to leverage standardization advantages during product iteration and upgrades, addressing diverse application scenarios and performance requirements.
As a result, standardization continues to unlock greater value, transforming automotive components into energy carriers and batteries into a standardized element in the automotive sector.
In-Situ Upgrades
Adapt to Changing Needs with a Consistent Foundation
As automotive iterations accelerate at an unprecedented pace due to diverse application scenarios and performance demands, the key challenge for new energy vehicle development lies in meeting diverse performance requirements while maintaining standardization.
Large cylindrical batteries address this through in-situ upgrades enabled by consistent dimensions and integrated multiple chemical material systems, flexibly adapting to different performance needs.
From LFP to LMX and NCM mid-to-high nickel chemistries, these batteries can dynamically adjust energy capacity, driving range, charging times, and power outputs to match vehicle requirements.
It is interesting to note that we are seeing the highest production energy dense cells are in the 21700 cylindrical format.
By leveraging mature material system platforms, in-situ upgrades reduce battery system development time to 3-6 months while cutting R&D costs (including personnel, product validation, component tooling, and production line adjustments) by nearly 80%, significantly optimizing both time and financial resources.
Zero Swelling
Rendering Stress Management Obsolete
The circular geometry of large cylindrical batteries ensures uniform stress distribution from the beginning to the end of their lifecycle, eliminating axial swelling entirely.
In contrast, prismatic cells experience swelling during their lifecycle, complicating modular assembly and necessitating stress management to prevent structural and deformation failures.
In a Cell to Pack or Cell to Body design the management of the cell swelling is a significant challenge. Do you focus on the requirements around the cell performance and lifetime requirements or managing the structural performance of the pack and vehicle? The cylindrical cell is a self contained dimensionally stable unit and hence the structural performance of the pack is the same at the end of life as it was at the beginning of life.
Statistics show that in prismatic cell applications, swelling-related quality issues account for over half of total after-sales problems. Compared to prismatic cells, the zero-swelling characteristic of large cylindrical batteries guarantees consistent performance throughout the entire lifecycle, rendering stress management obsolete.
Intrinsic Safety
Drive with Confidence
When electric vehicles place batteries in the chassis, complex road conditions can cause bottom impacts that may trigger battery failures or even safety incidents, resulting in significantly higher insurance claim rates for new energy vehicles compared to traditional fuel-powered cars.
Large cylindrical batteries feature a steel casing with 550MPa strength—5.5 times that of prismatic aluminum casings (95MPa). Combined with a 1500MPa dual-layer hot-formed steel bottom design and 3500MPa aerospace-grade fiberglass, they achieve crash energy absorption of 1000J—6.6 times the national standard.
Even in extreme scenarios with battery impacts, the directional pressure relief design at the bottom releases 50% of the enthalpy into the relief chamber within 5 seconds, preventing temperature rises in adjacent cells.
Paired with the gas-electric separation design of the battery pack, this effectively eliminates thermal runaway, ensuring true intrinsic safety and enabling drivers to operate with complete confidence.
Author: Woody Wu at power9tech.cn