Moving from 314 Ah to 500 Ah-plus cells: what changes on a module and PACK line

Where do large cells stand today?

From mid-2025, leading cell makers began mass-producing storage cells of 500 Ah and above. By the first half of 2026 these cells had passed one tenth of utility-scale storage cell shipments, and the industry expects that share to keep rising this year. 314 Ah is still the largest-volume format, in tight supply, with prices up more than 15 % in six months.

Typical figures for common formats (dimensions vary a little between makers; the cell datasheet rules):

Format	Energy per cell	Weight	Size (approx.)	20-ft container
314 Ah	1.00 kWh	5.5–5.6 kg	72 × 174 × 207 mm	about 5 MWh
587 / 588 Ah	1.88 kWh	10–10.6 kg	72–74 × 274–310 × 214–222 mm	about 6.25 MWh
628 Ah	2.01 kWh	about 11.3 kg	72 × 352 × 205 mm	about 6.9 MWh
684 Ah (stacked)	about 2.19 kWh	—	—	about 6.9 MWh
1000 Ah and above	over 3 kWh	from about 20 kg	over 500 mm long	larger systems

The big win is at system level: more energy in the same container, with fewer parts, connections and integration steps. A 628 Ah cell, for example, is about as wide as two 314 Ah cells side by side, so some PACK structures carry over.

Which stations change with large cells?

Following the station order of the 8 PPM line on this site:

Station	From 314 Ah to 500 Ah-plus	What to do
Depalletizing and infeed	Cell weight rises from about 5.6 kg to 10–11 kg	New grippers and tray locating; check robot payload — five cells per pick go from about 28 kg to about 53 kg
Scan / OCV test	Larger cell, lower internal resistance	New test fixtures and probe positions; confirm IR range and resolution cover the large cell
Stacking and pressing	Face area about 1.7× larger	At the same face pressure, press force is about 1.7× higher; check press stroke and fixture width
Terminal addressing	Terminal positions and pitch change	Update vision programs and recipes; positioning accuracy stays the same
Busbar welding	Larger busbar section, cell current about doubles	Re-qualify weld parameters (penetration, width, pull), raising laser power or changing the spot if needed
Module EOL	Higher operating current	Confirm current ranges for DC resistance and similar tests; new contact fixtures
Conveyor and module handling	Heavier, wider modules	Check pallet-conveyor load rating and pallet size
PACK assembly and test	Structures, cooling plates and harnesses change	New assembly fixtures; leak-test and EOL fixtures follow

One change is easy to miss: the number of welds. With two terminals per cell, 314 Ah needs about 1,990 welds per MWh and 587 Ah only about 1,065 — about 46 % fewer. Fewer welds raise the bar for each one, since each carries more current.

How do takt and output change?

At the same takt in cells per minute, large cells nearly double the energy output:

Cell	Energy per hour at 8 PPM	Annual output (20 h × 300 days × 85 % OEE)
314 Ah	about 482 kWh	about 2.46 GWh
587 Ah	about 902 kWh	about 4.60 GWh
628 Ah	about 965 kWh	about 4.92 GWh

Re-check the real takt for the large cell: weight- and size-driven moves such as handling and pressing may slow down, while welding may speed up because there are fewer welds. For the method, see PPM to GWh: line capacity.

Retrofit the existing line or build new?

A retrofit is worth considering when:

• the large-cell module still fits the line’s envelope (the 8 PPM line on this site takes modules of H 100–240 mm, W 150–370 mm and L 300–1000 mm; 587, 588 and 628 Ah cells fit in height and width, and module length depends on the series count);
• robot payload, press force and conveyor load have enough headroom;
• the changes are mainly grippers, fixtures, tooling and programs.

Build new, or redesign the key stations, when:

• cell length or weight is outside the line’s range (cells above 1000 Ah, for example);
• robots, presses or testers have no headroom and the retrofit costs approach new equipment;
• you also want a big step up in takt or automation, and the retrofit is the moment to do it.

Start with a compatibility review: take the target cell’s datasheet and the module and PACK drawings, and check size, weight, force and current station by station.

A flexible line for both 314 Ah and large cells

• Pick a main format. Running several cell formats in one plant cuts utilisation noticeably through changeover losses. Set the main format from your order book and cover the rest.
• Put changeover times in the contract. Target times for swapping grippers, fixtures and welding tooling, and the first-article procedure, belong in the technical agreement.
• Modular tooling. Quick-change fixtures and test tooling, with recipes sent from MES, cut setup errors.
• Size key equipment for the large cell. Choose robots, presses, lasers and EOL testers for the large-cell maximum; the small cell is then covered.

What we can supply

The 8 PPM line on this site is designed around the 314 Ah cell with 587 Ah compatibility built in. For 628 Ah, 684 Ah and cells above 1000 Ah, we can supply complete lines or single machines through our supply-chain service, and review an existing line’s compatibility with a retrofit plan.