# CATL expands Seres pact to add 12 GWh battery capacity in Chongqing
*The expanded plant-in-plant project will push combined annual output past 20 GWh, supplying packs for up to 260,000 Huawei-partnered AITO vehicles.*
**Published:** November 10, 2026
**By:** Lian Chen
**Section:** Batteries & Electric Vehicles — China
**Format:** Company Watch
**Confidence:** medium
**Source:** https://eastasiabrief.com/batteries-ev/catl-expands-seres-pact-add-12-gwh-battery-capacity-1306
**Publisher:** East Asia Brief (https://eastasiabrief.com/)
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## What to know
- Phase 2 expansion adds 10 to 12 GWh annually to lift Chongqing site capacity past 20 GWh
- CATL locks in exclusive battery supply across more than 1.2 million cumulative AITO vehicles
- Joint overseas market evaluations in Europe and the Middle East scheduled for early 2027
*Robotic arms assemble electric vehicle battery packs along an automated production line as technicians monitor operations. (AI-generated image)*
Contemporary Amperex Technology Co., Limited reaffirmed an expanded strategic supply agreement with SERES Group on Nov. 10, 2026, securing long-term battery deliveries across all AITO brand electric vehicles.
The agreement accelerates construction of Phase 2 of the plant-in-plant manufacturing project inside the Seres Super Factory in Chongqing. The expansion adds 10 to 12 gigawatt-hours of annual battery pack assembly capacity.
Combined annual output across both production phases will exceed 20 gigawatt-hours once Phase 2 enters service. That volume provides sufficient pack capacity to assemble between 130,000 and 260,000 electric vehicles each year, depending on battery pack sizing.
Cumulative deliveries under the AITO brand passed 1.2 million vehicles since vehicle production began, Seres said. The premium marque has installed CATL battery cells in every production model built since its commercial debut.
The one-millionth AITO vehicle rolled off the Chongqing assembly line in January 2026, 46 months after the brand delivered its first vehicle. The rapid ramp made AITO the fastest Chinese new energy vehicle brand to reach that milestone.
The embedded manufacturing framework locates battery pack lines directly inside the automaker's vehicle assembly plant. Eliminating road transit between separate facilities reduces cell degradation risks and cuts factory inventory cycles from several days to under an hour.
CATL began operating two cell-to-pack 2.0 lines at the Seres facility on June 30, 2025. The installation was CATL's first dedicated production base in Chongqing and its initial industrial deployment of the plant-in-plant format.
Cell-to-pack — an assembly method that mounts cells straight into packs without intermediate module enclosures — improves internal space efficiency. The engineering method increases battery energy density while lowering chassis weight and production costs for automakers.
CATL Chairman Robin Zeng and Seres Chairman Zhang Xinghai signed the deepening agreement at Seres headquarters in Chongqing. Both corporate leaders agreed to coordinate engineering across cell chemistry, chassis integration and software systems.
Beyond manufacturing capacity, the agreement outlines joint construction of an ultra-fast charging network and full-lifecycle battery services. The service architecture monitors cell degradation from initial vehicle delivery through second-life grid storage and end-of-life material recycling.
Seres manufactures and markets the AITO brand in close partnership with Huawei Technologies under the Harmony Intelligent Mobility Alliance. Huawei provides cockpit software, autonomous driving algorithms, electric drive units and sales distribution through its national consumer flagship stores.
Locking in exclusive supplier status across AITO protects CATL against pricing pressure from rival battery manufacturers. Competitors like CALB and Sunwoda have offered aggressive discounts to Chinese vehicle manufacturers seeking secondary battery sources.
The supply pact follows a related technology agreement signed on Oct. 19, 2026, between CATL and Huawei smart car subsidiary Yinwang. That arrangement links Huawei's Qiankun autonomous driving system with CATL's Choco-Swap automated battery replacement stations.
The Yinwang collaboration aims to complete hands-free battery pack swaps in 99 seconds. Vehicles position themselves over automated bays using autonomous parking sensors before robotic ground mechanisms exchange depleted cell packs for charged replacements.
The Chongqing expansion also supports municipal targets to establish a 1 trillion yuan ($138 billion) intelligent new energy vehicle industrial cluster. Local authorities have encouraged key parts suppliers to construct on-site capacity to minimize supply chain disruptions.
Direct integration into the Seres Super Factory insulates final assembly from long-distance transport disruptions across southern China. Keeping pack assembly inside the main factory allows Seres to match battery delivery cadence directly to final vehicle trim schedules.
The two companies also agreed to establish joint sales and technical support channels for export markets. The international strategy targets new energy vehicle demand across Europe, the Middle East and Central Asia.
The partners scheduled joint market entry evaluations for overseas export channels across Europe, the Middle East and Central Asia for early 2027, according to company filings.
The official notices do not disclose the total monetary value of the supply contract. Both companies also omitted the final expiration date and multi-year volume commitments of the renewed agreement.
Neither company published a construction ground-breaking date or commercial commissioning deadline for the Phase 2 expansion. Seres has not stated the specific capital expenditure budget allocated for the new factory floor space.
Seres shares rose 2.8% to close at HK$34.74 on the Hong Kong stock exchange following the cooperation announcement. CATL continues operating its two active CTP 2.0 lines inside the Chongqing assembly complex.
## Impact map
| Event | Korea | China | Japan | Global impact |
| --- | --- | --- | --- | --- |
| AITO battery supply agreement | LG Energy Solution and SK on face closed supplier loop across Huawei premium EV fleet | CATL defends domestic premium share with dedicated 20 GWh Chongqing pack lines | Panasonic excluded from Seres supply chain as embedded localized packaging expands | Embedded pack lines reduce transit risk while supporting planned 2027 vehicle exports |
## In this story
- **Companies:** Contemporary Amperex Technology, SERES Group
- **Tickers:** 300750.SZ, 601127.SS, 09927.HK
- **Exposed:** Huawei Technologies, Yinwang
- **Impact:** Supply Chain, Capex, Order Book
## Primary sources
1. batteriesnews.com
2. catl.com
3. battery-energy-storage-system.com
4. ev-route.com
5. iresearch.cn
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Cite as: East Asia Brief, "CATL expands Seres pact to add 12 GWh battery capacity in Chongqing," November 10, 2026. https://eastasiabrief.com/batteries-ev/catl-expands-seres-pact-add-12-gwh-battery-capacity-1306