Manufacturing & Gigafactories Developed 2023 · C9 4 min

Process Considerations for Resilient and Flexible Battery Cell Manufacturing

Battery cell manufacturing sits at the centre of the electric mobility transition, yet the process itself has not advanced as quickly as the cells it produces. This case study asks what the next generation of cell production should look like to stay economic, sustainable and ready for rapid scale-up. With forecasts pointing to more than four terawatt-hours of needed cell capacity and over 300 gigafactories by 2030, the stakes for getting the process right are high.

The Problem: Manufacturing Lags the Cell

Lithium-ion cells have improved dramatically, with specific energy density rising from around 150 to nearly 300 watt-hours per kilogram over recent decades, while cell prices fell from over 1,000 US dollars per kilowatt-hour in the early 2000s to about 151 in 2022. The manufacturing process, however, still accounts for roughly a quarter of cell cost. Production runs through three stages, electrode manufacturing, cell assembly and cell finishing, broken into about 15 steps. Analysis of energy and greenhouse gas data, drawn largely from a German research factory for battery cells, showed that only a handful of steps dominate the footprint. Electrode coating and drying, cell formation, and drying room operation together consume about 76 percent of total energy and produce around 74 percent of emissions.

Approach: Target the Heavy Steps

Because the impact is concentrated, the study focuses improvement effort on the worst offenders. Coating and drying are the largest natural gas consumers, driven by an oven up to 150 degrees Celsius running along an 80-metre line, plus solvent recovery. Drying rooms are energy-hungry because dehumidification units must be regenerated to keep assembly air dry. Cell formation is the single biggest electricity consumer, near half of the total, due to charge and discharge losses and the cooling needed to hold cells at constant temperature. A representative state-of-the-art process consumes roughly 41.5 kilowatt-hours per kilowatt-hour of cell capacity and emits about 10.3 kilograms of carbon dioxide equivalent per kilowatt-hour. Formation alone accounts for around 30 percent of emissions, with drying and drying rooms adding about 22 percent each.

Findings: Technology Levers and Real Savings

The case identifies concrete technology moves for each bottleneck. Moving from wet, solvent-based coating to a dry electrode process can remove two energy-intensive steps and cut energy use by about 25 percent. Redesigning drying rooms so only the assembly zone is kept dry, rather than the whole line, can reduce that step's energy by 35 to 65 percent. Partial charge and discharge protocols during formation, instead of full cycling, can lower formation energy by close to 50 percent. The study also stresses that emissions depend heavily on the local electricity mix: a process powered only by clean electricity could drop overall emissions from roughly 4.54 to 0.53 kilograms of carbon dioxide equivalent per kilowatt-hour, since gas-related emissions stay fixed while grid emissions vary by country.

What It Means for Gigafactories

Beyond efficiency, the case examines resilience and flexibility. Scaling output means installing multiple identical assembly and finishing lines, so energy use rises roughly linearly with added machines, making per-step efficiency compound at scale. To stay resilient, the study points to digitalisation and automation, industrial Internet of Things with data-driven operations, and stronger labour and performance management using augmented and virtual reality for training. Adaptability to new chemistries, including solid-state batteries, is framed as starting with single-step changes rather than wholesale line rebuilds, letting a gigafactory evolve as technology shifts.

Key Takeaways

Cell manufacturing still represents about 25 percent of cell cost, even as energy density has roughly doubled and prices have fallen sharply.

Three steps, electrode coating and drying, cell formation, and drying room operation, drive around 76 percent of energy and 74 percent of emissions.

A dry electrode process can cut coating and drying energy by about 25 percent by removing wet-process steps.

Confining dry conditions to the assembly zone can reduce drying room energy by 35 to 65 percent.

Partial charge and discharge formation protocols can lower formation energy by close to 50 percent.

Powering production with clean electricity could cut process emissions from about 4.54 to 0.53 kilograms of carbon dioxide equivalent per kilowatt-hour.

Resilience and adaptability rely on automation, industrial IoT and step-by-step readiness for chemistries such as solid-state batteries.