BYD is making headlines on two fronts this week: advanced battery engineering and booming EV sales. In China, the company has published a new patent application for an immersion-cooled battery cabinet that places cell modules directly in dielectric fluid while keeping electrical equipment in a separate dry chamber. At the same time, BYD’s flagship Great Tang SUV has now recorded more than 10,000 monthly sales for three consecutive months, underlining how the automaker is pairing aggressive product innovation with real commercial momentum in the Chinese EV market.
BYD’s New Battery Patent Targets a Core EV Thermal Challenge
According to a patent application published by the China National Intellectual Property Administration (CNIPA) on October 5, 2026, under number CN 122868832 A, BYD has proposed a battery cabinet design that separates the enclosure into two isolated chambers:
- A lower liquid-filled compartment containing battery cell modules submerged in dielectric cooling fluid
- An upper dry compartment housing electrical equipment and connections not intended to operate in liquid
The concept addresses a key engineering problem in immersion cooling: how to maintain reliable electrical and signal connections across a liquid-tight barrier.
Unlike conventional indirect liquid cooling, where coolant flows through cold plates attached to battery modules, immersion cooling places the modules directly in a non-conductive fluid. That shortens the thermal path and can improve heat extraction, especially in high-power charging and heavy-duty cycling environments.
Why the Patent Matters
The significance of BYD’s filing is not just that it uses immersion cooling. The real innovation appears to be in how the company routes connections between wet and dry zones.
Key details from the application include:
- The battery cabinet is divided into two isolated chambers
- Electrical and signal leads are routed through the upper portion of the liquid compartment
- The design avoids bringing connections through the floor or side walls of the wet chamber
- This architecture is intended to maintain liquid sealing while protecting sensitive electrical components
In practical terms, this could help solve one of the biggest hurdles in immersion-cooled battery packs and stationary energy storage systems: balancing thermal performance, serviceability, and electrical isolation.
How BYD’s Approach Differs From Today’s Mainstream Cooling Systems
Most current production battery systems still rely on indirect liquid cooling rather than full immersion.
For example:
- BYD MC Cube energy storage systems use Blade batteries in a cell-to-system architecture
- BYD MC Cube-T specifies liquid cooling, but not full cell immersion
- CATL EnerOne and EnerC systems also use liquid cooling with cooling plates outside the battery modules
- CATL Qilin battery integrates a cooling plate into a multifunctional interlayer between cells
These designs all keep coolant within a defined channel or thermal interface, rather than surrounding the modules directly.
Cooling Architecture Comparison
| System/Approach | Cooling Method | Key Characteristic |
|---|---|---|
| Conventional battery pack | Indirect liquid cooling | Coolant flows through cold plates attached to modules |
| CATL Qilin | Integrated liquid cooling interlayer | Cooling plate positioned between adjacent cells |
| BYD MC Cube / MC Cube-T | Liquid-cooled energy storage | Externalized cooling path rather than immersion |
| BYD patent CN 122868832 A | Immersion cooling | Cell modules submerged directly in dielectric fluid |
From an engineering standpoint, immersion cooling can offer several potential benefits:
- Faster heat dissipation
- Better temperature uniformity across cells
- Stronger support for ultra-fast charging
- Possible gains in cycle life and safety under high loads
However, it also introduces tougher sealing, materials compatibility, and maintenance challenges. That is why BYD’s focus on the chamber boundary and cable routing is noteworthy.
Great Tang Sales Show BYD’s Flagship Strategy Is Working
While BYD explores next-generation battery systems, it is also scaling premium EV sales at speed. The company’s new Great Tang flagship SUV has now topped 10,000 sales for three straight months since launching in China in mid-June 2026.
In September alone, BYD sold 13,010 Great Tang units, bringing cumulative sales to 40,222.
That performance is especially striking because the Great Tang sits at the upper end of the market as BYD’s first D-segment flagship SUV in the Dynasty lineup.
Great Tang Sales Momentum at a Glance
| Metric | Figure |
|---|---|
| First 24-hour preorders | 30,000+ |
| Preorders after two weeks | 100,000+ |
| Preorders by launch | 150,000+ |
| September 2026 sales | 13,010 |
| Total sales since launch | 40,222 |
| Consecutive months above 10,000 sales | 3 |
For a large, premium Chinese EV and PHEV SUV, those are powerful early numbers. They suggest BYD is not just dominating the mass market; it is also proving it can move high-end vehicles at serious volume.
Great Tang Specs: Big Battery, Big Range, Ultra-Fast Charging
The Great Tang is sold in both battery electric vehicle (BEV) and plug-in hybrid (PHEV) forms, giving BYD flexibility in a market where buyers still value multiple powertrain options.
Key Great Tang Highlights
- Available in EV and PHEV variants
- Base Premium EV starts at 239,900 yuan (about $35,500)
- Flagship EV starts at 269,900 yuan (about $40,000)
- All versions use second-generation Blade Batteries
- Base battery capacity: 105.79 kWh
- Larger battery option: 130.15 kWh
- Claimed CLTC range: up to 950 km (around 590 miles)
- Built on a 1,000V architecture
- Supports BYD Flash Charging
- Claimed charging time: 10% to 70% in 5 minutes
- Claimed charging time: 10% to 97% in 9 minutes
Those charging figures, if consistently repeatable in real-world conditions, would place the Great Tang among the most aggressively fast-charging large EVs anywhere in the world.
Great Tang Dimensions and Market Positioning
| Specification | Great Tang |
|---|---|
| Length | 5,263 mm |
| Width | 1,999 mm |
| Height | 1,800 mm |
| Wheelbase | 3,130 mm |
| Seating layout | 2+2+3 |
BYD says the SUV includes 29 “world firsts,” and one of the more unusual packaging points is its 2+2+3 seven-seat layout, a format designed to maximize flexibility in a full-size family SUV.
Dimensionally, the Great Tang is:
- Larger than the Hyundai IONIQ 9
- Larger than the Kia EV9
- Roughly comparable in size to the Li Auto L9
That places it squarely in the increasingly important full-size electrified SUV segment, where Chinese brands are moving quickly to redefine value, technology, and interior packaging.
Connecting the Dots: Battery R&D and Product Success
These two developments may seem separate, but together they reveal a lot about BYD’s strategy.
On one side, the company is investing in deep battery R&D, including thermal management concepts that could influence future EV platforms and energy storage products. On the other, it is monetizing its battery expertise through high-volume vehicles like the Great Tang, which already uses second-generation Blade Battery technology and a 1,000V high-voltage architecture.
That matters because EV competition is increasingly being decided by a few core technical battlegrounds:
- Charging speed
- Thermal control
- Battery safety
- Packaging efficiency
- Cost scaling
BYD is trying to compete on all five at once.
Why This Matters Globally
BYD executive vice president Stella Li has already said the Great Tang is expected to reach Europe and other overseas markets by the end of 2026 or early 2027. That means the SUV is not just a domestic success story; it could become a serious export product in the next phase of BYD’s international expansion.
For global automakers, there are two clear signals here:
- Chinese EV makers are moving upmarket fast. BYD is no longer only a value brand. It is building large, premium, technology-heavy SUVs with compelling specs and strong pricing.
- Battery innovation remains a major differentiator. Whether or not BYD commercializes this exact immersion-cooled patent soon, the filing shows the company is actively exploring architectures beyond today’s mainstream liquid-cooling solutions.
If BYD can combine advanced battery thermal systems with its scale advantages in batteries, semiconductors, and vehicle manufacturing, it could strengthen its already formidable position against both Chinese rivals and legacy global brands.
What to Watch Next
The next questions are straightforward:
- Will BYD bring this immersion-cooled battery design into production, and if so, in vehicles, energy storage, or both?
- Can the Great Tang maintain 10,000-plus monthly sales as early demand normalizes?
- How competitive will its pricing and specifications look once it reaches Europe and other export markets?
For now, BYD is showing why it remains one of the most important companies in the global EV industry. It is not just selling electric vehicles in huge numbers; it is still pushing hard on the underlying battery technologies that may define the next generation of performance, charging, and safety.
