CATL and Seres Expand Dedicated Battery Capacity to 20 GWh

Seres Group and Contemporary Amperex Technology signed an agreement Oct. 11, 2026, to expand dedicated battery capacity inside the carmaker's Chongqing assembly plant to more than 20 gigawatt-hours annually.

The deal accelerates construction of Phase II at CATL's facility inside the Seres Super Factory. The expansion adds 10 to 12 gigawatt-hours of annual pack capacity, the companies said.

Phase I began operating two cell-to-pack assembly lines at the Chongqing site on June 30, 2025. The second phase will double site output to meet rising vehicle assembly volumes.

Seres confirmed its premium electric vehicle marque, Aito, will source traction batteries exclusively from CATL across its entire model range under the long-term pact.

Aito vehicles equipped with CATL batteries have surpassed 1.2 million cumulative deliveries since the partnership started, Seres Chairman Zhang Xinghai said during the signing ceremony.

CATL Chairman Robin Zeng attended the Chongqing event alongside Seres leadership. Both executives committed to joint development across vehicle platforms, battery lifecycle management and overseas export logistics.

The agreement deepens a manufacturing model Chinese industrial planners call a plant-within-a-plant. In this layout, cell makers assemble battery modules directly beside final automotive chassis lines.

Co-located manufacturing eliminates long-distance transportation of heavy battery enclosures. It reduces road freight costs and limits transit vibration risks for delicate battery management wiring.

The setup also allows the assembly plant to operate with minimal line-side inventory. Battery packs roll directly onto automated guided vehicles that transfer them straight to vehicle marriage stations.

Automakers in China are using in-plant battery manufacturing to reduce order-to-delivery lead times. The approach helps domestic electric vehicle brands defend margins against joint-venture legacy competitors.

The Chongqing partnership began on Aug. 27, 2022, when Seres signed an initial five-year agreement to adopt CATL's Qilin battery architecture in premium Aito models.

The companies signed an initial deepening pact on Dec. 20, 2023, which laid the legal framework for the Chongqing co-located factory project.

Beyond pack assembly, the updated agreement expands joint work into high-voltage supercharging infrastructure. The two manufacturers plan to build shared ultra-fast charging corridors across southwestern China.

The companies also agreed to develop battery-swapping systems for Seres commercial and passenger fleets, including the automaker's AIVA vehicle brand, the companies said.

The pact establishes an operational framework for shared international sales channels. The groups plan to export assembled vehicles and establish service networks across Europe, the Middle East and Central Asia.

Seres depends heavily on the Aito brand, which it develops jointly with telecommunications giant Huawei Technologies, to sustain its share in China's premium automotive segment.

For CATL, locking in high-volume vehicle assembly lines protects production utilization. China's top battery maker faces expanding domestic cell capacity from mid-tier competitors such as CALB and Gotion High-tech.

Securing dedicated in-plant volume shields CATL from sudden supplier switching by vehicle brand managers seeking short-term cell discounts, industry analysts said.

The companies did not disclose capital expenditure figures or the specific financial division of construction costs for the Phase II expansion in Chongqing.

The announcement also did not state an official commissioning deadline or commercial production start date for the new Phase II assembly lines.

Existing supply commitments under the original five-year pact run through August 2027. The companies plan to review regional supercharging rollout schedules during their first quarterly working session in early 2027.