China’s third-largest power battery manufacturer has launched a comprehensive quality and safety overhaul after its lithium iron phosphate (LFP) cells exhibited widespread swelling in GAC Aion vehicles. The company has strengthened manufacturing tolerances, enhanced traceability, restructured its validation systems and revised its organizational and customer-relations processes, according to a report by local media outlet Auto Time.
On the production side, thickness measurements and areal-density controls in the electrode coating process have been tightened to within ±1.5%—bringing them in line with industry best practices. Online monitoring of dew point and moisture levels during electrolyte filling has also been upgraded. Batch-sample traceability has been refined from daily checks to the individual roll level, enabling faster root-cause analysis.
The company is conducting a retrospective audit of all incoming raw and auxiliary materials, as well as additive formulations used in 2022 and 2023, and has discontinued certain low-margin additives. It has also rewritten design standards for cell casings, explosion-relief valves and terminal post welding margins, enhancing durability and safety redundancy.
A dedicated rapid-response customer quality team has been established within the passenger vehicle division to jointly monitor battery management system data with major automakers. For the first time, the quality department holds veto power over batch releases, ensuring that no assembly—regardless of project deadlines—can bypass approval if it fails to meet internal standards.
The reforms follow reports in July that Aion S sedans equipped with 177-Ah LFP cells experienced cell swelling, electrolyte leakage and occasional power loss after covering 150,000–300,000 kilometers. Dubbed the “banana battery” controversy, the issue affected roughly 220,900 units sold in 2023, 72% of which served ride-hailing and taxi fleets. In response, the automaker extended warranties on affected models to eight years or 300,000 kilometers, offering free inspections and replacements. The battery maker has opened a direct maintenance channel and pledged full responsibility for cell quality.
While these measures are expected to raise production costs and pressure profit margins, the company reported a 71.2% year-on-year revenue increase to 11.8 billion yuan in the first quarter, with 7.31 GWh of domestic deployments (5.86% market share) and 5.2 GWh installed in June (6.82% share).
Source: CNEV Post
