#automatedconveyorsolution

Solar cell production lines run several processes at different speeds. Stringers solder cells into strings. Layup stations arrange strings into matrices. Laminators then seal each matrix under heat and pressure. Each stage carries its own cycle time. Therefore, a speed mismatch between stations creates a bottleneck somewhere on the line. A stop-and-go circular conveyor solves this exact problem. It sits between two stations and absorbs the timing gap. Consequently, the faster station never waits and the slower station never starves. Moreover, this same buffering logic applies across new energy manufacturing, not just solar cells. Furthermore, plant engineers must solve this timing problem for every new line, regardless of cell technology. This article examines the stop-and-go circular conveyor as a buffer conveyor system in solar cell manufacturing. It also covers its extension into battery cell production lines.

What Is a Stop-and-Go Circular Conveyor in Solar Cell Buffer Systems?

A stop-and-go circular conveyor is a closed-loop track. It carries product carriers in a controlled start-stop motion. Each carrier holds one solar cell or one cell string. The drive indexes the loop forward on command. Then it halts the loop so a robot can load or unload a carrier. This stop-and-go motion protects fragile wafers from vibration damage. Moreover, the closed loop lets carriers recirculate indefinitely. As a result, buffer depth is not limited by conveyor length alone. Next, engineers set carrier pitch, loop diameter, and index speed together. This combination keeps dwell time correct between the stringer and the layup station. In addition, the loop shape saves floor space compared with a long straight buffer.

Core Functions of a Loop Conveyor Line in Cell Buffering

A stop-and-go circular conveyor performs several distinct functions inside a solar cell buffer conveyor system. First, it decouples stringer output from layup input. The stringer produces one string per cycle. The layup station may pause for matrix inspection. Meanwhile, the stop-and-go circular conveyor holds completed strings. The stringer never has to halt. Second, it preserves string sequence. Carriers enter the loop in production order. They exit in the same order. Therefore, the layup station always receives strings in correct sequence for matrix assembly. Third, it enables gentle indexing. The stop-and-go drive accelerates and decelerates each carrier smoothly. Consequently, thin wafers and half-cut cells avoid crack propagation during transfer. Similarly, multi-busbar cells avoid ribbon misalignment during the stop phase. Fourth, it supports flexible dwell time. Operators adjust the index interval through the controller. Thus, the same stop-and-go circular conveyor buffers different cell formats without any hardware changes. This flexibility covers M6, M10, and G12 wafer sizes on one machine.

Technical Specifications of a Circular Conveyor Line System

Parameter

Typical Range

Function

Loop diameter 1.2 m – 3.5 m Sets total carrier count around the buffer Carrier pitch 150 mm – 300 mm Matches cell or string width Index cycle time 1.5 s – 4 s Matches upstream stringer cadence Positioning accuracy ±0.1 mm Aligns each carrier for robot pick Drive type Servo motor with cam indexer Delivers smooth stop-and-go motion Carrier capacity 40 – 160 units Sets total buffer depth Load per carrier 0.5 kg – 3 kg Matches cell or string weight Sensor type Photoelectric occupancy sensor Confirms carrier fill status in real time

Performance in Solar Cell Production Lines

Real production figures show why buffer sizing matters. Ecoprogetti describes a 200 MW solar production line where the stringer runs at 40 modules per hour. The laminator on this same line processes only 35 modules per hour. This gap becomes the real bottleneck on the line. A stop-and-go circular conveyor placed between these two stations absorbs this five-module-per-hour gap. As a result, the stringer never has to slow down. Sticky Solar Power reports a single-track stringer design. This design outputs 5,000 cells per hour across continuous operation. A stop-and-go circular conveyor sized for this cadence gives the downstream layup station a stable, sequenced feed. This stable feed holds true even during short stringer stops for tape or ribbon changeovers. On a larger scale, JVG Thoma describes a 1,200 MW gigafactory design. A multi-stringer configuration reaches a combined output of 43,200 cells per hour in this design. This output feeds 24 laminators. Each laminator processes 48 modules per cycle. At this volume, buffer sizing becomes a core engineering decision rather than an afterthought. A stop-and-go circular conveyor scales its carrier count and loop diameter to match this cell rate. Every laminator then stays fed without a gap.

Stop-and-Go Circular Conveyor vs Linear Buffer Conveyor

Feature Stop-and-Go Circular Conveyor

Linear Buffer Conveyor

Buffer depth per footprint High; loop recirculation multiplies capacity Limited to physical conveyor length Carrier sequence control FIFO order maintained automatically Requires separate sequencing logic Floor footprint Compact, closed loop Extends floor space in one direction Cell handling Smooth index motion, low vibration Depends entirely on belt type Format flexibility Adjustable pitch and dwell time Fixed by physical conveyor length Integration point Fits between two asynchronous stations Best for single-speed transfer only

Extending Circular Conveyor Line Buffering to Battery Cell Manufacturing

Battery manufacturing shares the same throughput mismatch pattern as solar cell production. Similarly, cell stacking, formation, and aging stages each run at different speeds. Consequently, engineers apply the same stop-and-go circular conveyor logic to buffer battery cells between stations. For example, prismatic cell lines use a stop-and-go circular conveyor to hold cells between the stacking station and the electrolyte filling station. Round cell lines apply the same loop concept to accumulate cells before inspection or sorting. Likewise, formation and aging stages benefit from a buffer loop between them. Formation simply runs far slower than upstream assembly. Thus, a stop-and-go circular conveyor buffer conveyor system extends naturally from solar cell strings to cylindrical and prismatic battery cells. New energy manufacturing needs this compact, sequence-preserving buffer at many transfer points.

TallMan Robotics Conveyor Systems for New Energy Manufacturing

Conveyor Type

Buffer Method

Best Fit Application