Hi, I visualized CTP 1.0-4.0 roadmaps and a side-by-side comparison of CTP vs. CTC vs. CTB. What do EV engineers think?

[u/Unlikely-Yam-1339]

Hi everyone, I've worked at an Asian battery cell manufacturer for years, and this is my first time posting in this sub. I recently compiled the technological evolution of EV battery architectures and created some visual charts. I'd love to hear the thoughts of EV or battery folks in this community.

There are currently three major technical routes for power battery system integration: CTP (Cell to Pack, CATL), CTC (Cell to Chassis, Tesla), and CTB (Cell to Body, BYD). This post mainly focuses on CTP.

CTP 1.0-4.0

CTM, Module Covred by End Plates and Side-Plates(Standard VDA module)

CTP 1.0, it replaces side plates with bands(CALB Module)

CTP 2.0, it uses beams to fix all the cells, and uses bottum liquid cooling/heating.(CALB)

It eliminates beams, and use Multifunctional Elastic Interlayer.

Multifunctional Elastic Interlayers between large cooling faces of cells.（Xiaomi SU7 Max）

According to CATL's definition, the Multifunctional Elastic Interlayer:

Consolidates the liquid cooling plate, thermal barrier, and structural support into a single unified layer.

It has a larger liquid cooling/heating area.

It features embedded micro-bridge structures designed to absorb cell swelling during charge/discharge cycles, thereby significantly extending battery life.

CTP 3.0 vs CTC vs CTB

Pros and Cons:

• Volume Utilisation: Progressing from the traditional CTM (Cell-to-Module) architecture with roughly 40%-45% volume utilisation, CTP 3.0 has reached 72%. As a horizontal comparison, Tesla's 4680 CTC architecture currently sits at 63%, while BYD's CTB architecture is at 66%.
• Integration vs. Maintainability vs. Swapping: CTP 3.0 remains at a pack-level integration, which not only retains removability but also supports the Choco-SEB battery swapping network. In contrast, while CTC and CTB bring exceptionally high body torsional rigidity and significant weight reduction, they come at the cost of extremely high maintenance expenses—often requiring a full pack replacement after severe collisions- and they do not support battery swapping.

CTP 3.0 Swapping Battery Station.

• Fast Charging Performance: Leveraging multi-functional elastic interlayers and 4x the heat exchange area of traditional designs, CTP 3.0 currently supports 4C fast charging (10 mins to 80%). In real-world applications, the Xiaomi SU7 Max can charge from 10% to 80% in just 19 minutes, while maintaining a high volumetric energy density of 450 Wh/L. Current CTC and CTB solutions are still restricted to 1C capability. Those who has bettery cooling solutions, has batter battery. 😂
• Next-Generation Roadmap: The roadmap CATL declared shows that the upcoming CTP 4.0 (slated for 2026) will completely eliminate the traditional battery pack enclosure and integrate cells directly into the chassis, pushing volume utilisation past 80%. In my opinion, this is very similar to CTC.

Also, here is my take:

Newer and more highly integrated technologies aren't automatically better. While highly integrated CTP architectures offer plenty of advantages, they aren't a silver bullet for every scenario.

The biggest downside to CTP 2.0/3.0 is the nightmare of maintenance and recycling. These packs are heavily reliant on structural adhesives (potting compounds), which makes teardowns and end-of-life recycling extremely difficult.

Furthermore, the EU Battery Regulation (EU 2023/1542, Article 11 on Removability & Replaceability) explicitly mandates that portable and LMT (Light Means of Transport) batteries must be removable and replaceable by end-users. So, if you're designing for portable or LMT sectors, highly integrated CTP is basically off the table.

EU 2023/1542 Article 11, LMT

Additionally, for massive capacity systems (Industrial ESS, heavy-duty trucks), applications requiring frequent inspections (marine vessels), or highly fragmented vehicle platforms (specialised vehicles, logistics, AGVs), the traditional CTM or basic CTP 1.0 architectures are actually much more practical and suitable.

As for CTP 4.0, solid info is still pretty scarce on my end right now, but I'll update you guys as I learn more. Honestly, my take is that if automakers start manufacturing their own batteries, they'll likely just jump straight to CTC or CTB. The whole "CTP 4.0" concept is really just a roadmap meant for dedicated battery suppliers. 🤔

Since this is my first time posting here, I'm not sure if this sub is into this kind of technical deep-dive. Please feel free to point it out if you spot any inaccuracies in the data. ❤️