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.

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.

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.

• 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.

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. ❤️

What the title says. Looking to store excess from my solar into a 3-6 Kwh battery systems and don't want to invest thousands into a chemical that can burn down a house in an instant.

Edit: Thank you everyone for the responses. What I gather from the comments, its either LFP or sodium-ion one for home battery usage.

This is a Kinetic energy storage (KESS), also called Flywheel (FESS)

The idea is very old, variations already in use today.

The question is this design is uses a carbon fiber cylinder about 3~4 ft (~1m) in diameter, yet states they can provide 1000 kWh of energy storage, magnitudes more than others. THAT is what I am suspicious about.

Comparisons:

• Beacon Gen4. 25 kWh. 15 minutes of discharge
• Amber Kinetics M32. 32 kWh. 4 hours of discharge
  
• QNETIC: Q1. 1,000 kWh. 4 to 12 hours of discharge, design target

Massively more energy storage, using a less dense mass. The density of carbon varies depending on its form, but typically ranges from 1.5 to 2.1 g/cm³, while iron has a density of about 7.87 g/cm³.

Is this too fantastic, or possible to get close?

This was an intense project. Partially due to the Texas summer heat. Regardless it was a lot of fun.

Homeowner reached out in February inquiring about some earlier projects. They already had that beautiful pool built and had the plan for a patio cover all along. So, why not add some solar to it as well?

The utility company is Grayson Collin Electric Coop, and to my knowledge they’re the only one left allowing true 1:1 net metering in the state of Texas. We discussed foregoing batteries but with all the things going on in the world and myself having seen those things disappear in the blink of an eye the homeowner opted to go ahead with one. They’re already thinking of adding more soon.

Digging trenches always sucks but they’re especially awful in Parker, Texas. If anybody needs any rocks I know where to find them.

The system is roughly 70% offset and is chugging right along with projected production.

As the title stated the structure is steel framed 23’ x 27’ using all 11gauge 5” x 4” steel for posts, beams, and joists. The canopy is stained 2x6 boards bolted to the steel frame and covered with mod-bit roofing.

The city of Parker and GCEC were really cool and easy about stuff. I turned the solar permit in and applied for the interconnection agreement on a Thursday and had the green light for both by Monday morning of the next week.

The system was put through HDM and we got 25% of the system paid for since we used Domestic Content and I believe this house sits in an Energy Community.

We added the fan and 5 outlets to the structure after the solar was completed.

I included the original mock up I did in Google sheets to give an idea of what this thing was going to look like. Reference vs real life.

The homeowners are very kind, sweet people that I thoroughly enjoyed working with and getting to know. A lovely family with minds on the future and what’s potentially on the horizon. They may lurk the halls around here, I honestly don’t know, but they are very welcome and encouraged to chime in if they do.

I hope you enjoyed the post.

If you want to install a big battery in New York City, you have to cut through a notoriously tough tangle of regulations. That’s made it difficult to get large energy storage projects on the grid. 

Faced with those obstacles, some startups are getting creative, finding ways to use relatively small batteries in unexpected places, from induction stovetops to food carts. By deploying these more consumer-focused batteries, the companies are helping people directly, cutting pollution or power bills. And these units, while small on their own, could add up to a lot of capacity.

Source: MIT Tech Review's The Spark Newsletter

Hi all,

We're a team of BESS professionals, and we've been building BESSlayout, a tool for early-stage BESS site layouts.

How it works: draw your boundary on the map, and the solver packs the whole site. That currently covers DC blocks, PCS & MV skids, the E-house and internal roads. Safety distances, service clearances and boundary setbacks are all applied and editable to match local codes. Then you tune the inputs (gate, equipment, spacing rules) and hit Regenerate to compare options in seconds.

It's in beta right now (expect bugs..) and you can test it for free. We have a long backlog of improvements and features still to add. We're sharing it here because it could already be useful to some of you.

We're happy to take feedback, whether that's improvements, feature requests or bug reports.

Link: besslayout.com