Last updated: September 2026. Figures checked against the live LinkSolar pages on September 25, 2026.
A 182 × 183.75 mm N-type TOPCon cell on the LinkSolar shelf is rated 8.54 W at 25.5 % efficiency, while the 166 mm mono PERC cell next to it is rated 6.04 W at 22 %. Part of that gap is size, and part of it is the cell design.
TOPCon solar cells are n-type silicon cells with a tunnel oxide and doped polysilicon contact on the rear, a stack that cuts the losses at that surface. They typically run more efficient than PERC cells, are usually bifacial and are strung by machine. According to the U.S. Department of Energy, the industry is moving from PERC to n-type designs such as TOPCon.
This guide defines the TOPCon cell, compares it with PERC on the points a buyer notices, and places it next to the other n-type routes and the common cell sizes. It then covers who buys loose cells, lines up the specs in one table, explains how to read a datasheet and efficiency bin, and ends with a short FAQ. LinkSolar supplies 182 mm N-type TOPCon cells in packs of 10 to 100 for module and panel builds.
What is a TOPCon solar cell, and what does TOPCon stand for?
A TOPCon solar cell is a crystalline silicon cell built on an n-type wafer whose rear contact sits on an ultra-thin tunnel oxide covered by doped polysilicon, a stack that lets current out while stopping charge from being lost at the rear surface. TOPCon stands for tunnel oxide passivated contact. A passivated surface is one treated so that fewer charge carriers are lost there.
Every silicon cell loses some electrons where silicon meets metal, and cell engineers call that loss recombination. In a TOPCon cell, the oxide is thin enough for current to tunnel through it, and the doped polysilicon above it carries that current to the metal grid. The rear metal never touches bare silicon, so fewer electrons are lost before they reach the circuit.
PERC cells take a different route. They are generally built on p-type wafers, with a passivating layer on the rear that is opened in small spots so the aluminum contact can reach the silicon.
The front of the cell keeps a familiar layout: a fine metal grid, an anti-reflective coating and an emitter layer over the n-type wafer. The diagram below shows the typical stack from front to rear, with one label per layer.
According to the U.S. Department of Energy, Al-BSF cells led the global market until approximately 2018, when PERC designs overtook them on efficiency. The same page describes a second transition now under way, from PERC to n-type designs such as silicon heterojunction (SHJ) and TOPCon, and names efficiency as the driver again.
That shift is visible on the LinkSolar cell shelf. The 182 × 183.75 mm cell LinkSolar lists is an N-type TOPCon cell in a bifacial format, so both the front and the rear face collect light. To use that rear gain, the module around it needs rear-side optical access, which the listing asks buyers to verify.
TOPCon vs PERC: which cell is better for your build?
A TOPCon solar cell is the better choice when output per area, heat tolerance and rear-side gain matter most, while a PERC solar cell is still the practical choice when cost per cell and familiar handling matter more. PERC cells are generally p-type, with a passivating layer on the rear that is opened in small spots for the aluminum contact. TOPCon cells use an n-type wafer with a passivated contact across the whole rear, and that difference shows up on five axes a buyer can measure or feel.
- Efficiency class: The 182 × 183.75 mm N-type TOPCon cell on the live LinkSolar listing is rated at 25.5 % cell efficiency, against 21.5 % to 22 % on the live 166 mm PERC listings.
- Temperature behavior: According to PVEducation, the maximum power of a silicon cell drops by about 0.4 % to 0.5 % for every °C of temperature rise, and n-type TOPCon cells typically lose less power per °C than p-type PERC cells.
- Bifaciality: The LinkSolar TOPCon cell comes in a bifacial format, and while bifacial PERC is also available at 5.89 W for a full 166 mm cell, TOPCon generally collects more light from its rear face.
- Light-induced degradation: N-type wafers are generally less prone to the output loss that boron-doped p-type cells show in their first hours of sunlight.
- Price class: TOPCon generally costs more per cell than PERC but sits closer to it per watt, and both large-format cells use fine contacts meant for machine stringing.
Efficiency matters most when the outline of the panel is fixed. A product housing, a vehicle roof or a lab fixture only has so much area, and the higher efficiency class of TOPCon turns into more watts from the same footprint.
Temperature behavior matters most in hot installs. A panel on a dark roof or inside a sealed enclosure runs hot for much of the day, so a smaller loss per °C typically keeps more afternoon output.
Rear-side gain only counts when light can reach the back of the cell. The TOPCon listing asks buyers to verify encapsulation, rear-side optical access and back construction, so a bifacial cell laminated behind an opaque backsheet performs like a monofacial one.
PERC keeps its place in monofacial panels built on familiar tooling, where the per-cell price class and a well-known process count for more than the last few points of efficiency. For those builds, the 166 mm mono PERC cells rated 6.04 W come in packs of 15, 25 or 50 cells.
How do HJT and back-contact cells compare, and what sizes do TOPCon cells come in?
TOPCon, heterojunction (HJT) and back-contact are the n-type cell routes a cell buyer meets most often, and the TOPCon cell LinkSolar lists is a full 182 × 183.75 mm cell. According to the U.S. Department of Energy, the market is moving from PERC to n-type technologies such as silicon heterojunctions and tunnel-oxide passivated contacts, and the driver is efficiency.
- TOPCon: An n-type wafer carries an ultra-thin tunnel oxide under doped polysilicon on the rear, which cuts charge loss at that surface.
- HJT (heterojunction): Thin amorphous silicon layers typically cover both faces of an n-type wafer, and the cell is processed at low temperature.
- Back-contact (IBC): All metal contacts sit on the rear surface, which according to PVEducation removes front shading, makes cells easier to interconnect and lets them sit closer together in a module.
Large-format cells for module assembly on the live LinkSolar collection include 166 × 166 mm PERC, 158.75 × 79 mm half-cut PERC and 182 × 183.75 mm N-type TOPCon. Each silicon cell gives roughly 0.5 to 0.6 V under load regardless of size, so a larger cell mainly adds current. You can compare PERC, TOPCon and back-contact cell formats side by side before choosing a layout.
A half-cut cell keeps the voltage of the full cell and carries about half the current. The live bifacial PERC pair shows it clearly: the 166 × 166 mm full cell is rated 5.89 W at 21.5 %, while the 166 × 83 mm half cell is rated 3 W at 22 %. Both sit on the full and half-cut bifacial PERC cells page in 10-piece packs.
Lower current per string typically means lower resistive loss in the ribbons and less heat forced into one weak or shaded cell. According to PVEducation, hot-spot heating occurs when one low-current cell sits in a string of higher-current cells, and the power dissipated in that cell can crack cells or glass, melt solder or degrade the cell. The listed TOPCon cell comes in the full 182 × 183.75 mm format, and half-cut TOPCon cells are quoted on request.
Who buys loose TOPCon cells, and what should they know before stringing them?
Loose TOPCon cells are bought by module assemblers, R&D labs, custom small-panel makers and repair shops, and all four need a stringing setup built for thin multi-busbar cells. Each group reads the same listing for a different reason.
- Module assemblers: They buy the 182 × 183.75 mm cell for its bifacial format and 25.5 % cell efficiency, which raise output per unit of module area.
- R&D labs: A listed Voc of 0.75 V and a rated 8.54 W at 25.5 % give a known reference point when a lab benchmarks encapsulants, coatings or test rigs.
- Custom small-panel makers: They order TOPCon cells laminated into a custom panel and get back a buildable specification with cell layout, target Vmp and Imp and lamination.
- Repair shops: A replacement cell should match the old cell's current, because according to PVEducation one low-current cell in a string of higher-current cells overheats and can crack or degrade.
Large n-type TOPCon cells are thin and brittle, and their round-wire multi-busbar contacts are designed for stringing machines, so hand soldering usually fails and can leave microcracks. The LinkSolar listing asks buyers to keep the large cells supported during handling, storage and assembly, and to validate conductor sizing and soldering before a production run. Full-size TOPCon cells are not beginner cells.
For a hand-soldered prototype or a classroom kit, small cells that solder by hand are the practical starting point. Whatever the format, plan the series and parallel layout around the confirmed voltage and current, and match representative cells before they go into a string. LinkSolar lists both the large-format cells and the small hand-solder formats, so a prototype and its production version can be specified from one cell range.
Before a volume order, work through the checks for a cell maker versus a reseller so you know where each lot was sorted and tested. The same questions apply to any loose-cell listing you compare.
Specs to compare before you order TOPCon or PERC cells
Before ordering TOPCon or PERC solar cells, compare cell type, size, rated power, efficiency, voltage at maximum power, bifacial status and contact layout, then confirm in writing anything the listing leaves blank.
The table sets the TOPCon cell LinkSolar lists beside the three 166 mm PERC cells on the same shelf, using only the figures printed on each live listing.
| Cell type | Size (mm) | Rated power | Efficiency | Vmp | Bifacial | Contacts | Best fit |
|---|---|---|---|---|---|---|---|
| N-type TOPCon full | 182 × 183.75 | 8.54 W | 25.5 % | confirm | yes | thin multi-busbar | machine-strung bifacial modules |
| Mono PERC full | 166 × 166 | 6.04 W | 22 % | confirm | not stated | confirm | standard monofacial modules |
| Bifacial PERC full | 166 × 166 | 5.89 W | 21.5 % | confirm | yes | confirm | bifacial modules on a PERC budget |
| Bifacial PERC half | 166 × 83 | 3 W | 22 % | confirm | yes | thin multi-busbar | half-cut layouts with lower string current |
For the TOPCon row, open the 8.54 W bifacial TOPCon cell listing, which ships in packs of 10, 20, 50 or 100 cells.
Figures from the live LinkSolar cell listings on September 25, 2026, at the rated values shown; confirm per lot. For cells going into a product you sell, ask the supplier for its test report.
Each column answers a different ordering question.
- Cell type: This names the cell technology and whether you are buying a full cell or a half cell.
- Size (mm): Size sets the current each cell delivers, so plan every string around a single cell size.
- Rated power: This is the output per cell at the listed rating, and it grows with cell area as much as with cell design.
- Efficiency: Efficiency is power per unit of cell area, the fairer figure for comparing a 182 mm cell with a 166 mm cell.
- Vmp: Voltage at maximum power sets how many cells you place in series to reach your target voltage, so ask for it in writing wherever the table reads "confirm".
- Bifacial: A "yes" means the rear face also collects light, which pays off only when the module back lets light reach it, while "not stated" is a question to put to the supplier.
- Contacts: Thin multi-busbar contacts are laid out for stringing machines, so check that your stringing setup handles them before you order.
- Best fit: This is a starting match between cell and module type, and your layout and budget settle the final choice.
How do you read a TOPCon cell datasheet and efficiency bin?
A TOPCon cell datasheet is read by checking Pmax, Vmpp, Impp, Voc, Isc, efficiency and fill factor, then asking how the lot is binned, because the bin decides how evenly the cells share current in a string. The values below come from the live 182 × 183.75 mm N-type TOPCon listing, rated at 25.5 % efficiency.
- Pmax (8.54 W): Pmax is the rated maximum power of one cell, the figure used to size a module.
- Vmpp and Impp: These are the voltage and current at the maximum power point, and they are the numbers to plan series and parallel layout around.
- Voc (0.75 V): Open-circuit voltage is the cell voltage with no load connected, the highest voltage the cell shows.
- Isc (14.9 A): Short-circuit current is the current with the terminals shorted, the highest current the cell delivers.
- Fill factor: Fill factor describes how square the IV curve is, and a higher figure means lower internal losses.
Datasheets typically sort a lot three ways: by efficiency bin first, then by current class (Impp) inside that bin, then by front color grade for panels where appearance matters. Binning is like sorting eggs by weight before boxing them. Bin labels vary by supplier, so ask what each label means; see how to read a solar cell IV curve for where each value sits.
In a series string, current is shared by every cell, so a tight current class keeps each cell working near its own maximum power point. The listing gives rated values per cell, and the bin and current class of a specific lot are confirmed in writing at quote stage.
Illustrative example, not a listed spec: a buyer building 1,000 modules with the 8.54 W TOPCon cell asks for one efficiency bin and one current class per shipment. Every string then mixes cells within a narrow Impp band around the listed value, which meets the listing's note to match representative cells.
Finished products are sorted the same way. LinkSolar's partner factories build custom mini panels built with EL imaging and IV binning, followed by visual inspection, serialization and packaging.
FAQ: TOPCon solar cells
Are TOPCon cells bifacial?
TOPCon cells are commonly made in a bifacial format, so both the front and the rear face collect light. The 182 × 183.75 mm cell LinkSolar lists is an N-type TOPCon cell in a bifacial format. To gain from the rear side, the module needs rear-side optical access, so verify the encapsulation and back construction before you laminate.
What size are TOPCon cells?
The TOPCon cell LinkSolar lists is a full 182 × 183.75 mm cell rated 8.54 W. It comes in packs of 10, 20, 50 or 100 cells. Half cells and other cut sizes are quoted on request, so name the format you need when you ask.
Is TOPCon better than PERC?
TOPCon is the better cell when output per area, heat tolerance and rear-side gain matter most. The listed TOPCon cell is rated 25.5 % against 21.5 % to 22 % for the listed PERC cells, and n-type cells typically lose less power as they heat up. PERC remains the practical choice when cost per cell and familiar handling come first.
What is the difference between solar panels and solar cells?
A solar cell is a single piece of silicon that gives roughly 0.5 to 0.6 V under load, while a solar panel is a set of cells strung together and laminated into one sealed unit. Wiring cells in series adds their voltages, so the cell count sets the panel voltage and the cell size sets the current. For the full assembly process, see this guide to building a panel from finished cells.
Next step: Send LinkSolar the quantity, whether you need full or half cells, the efficiency bin, the packaging and the module the cells go into, and the specification is confirmed with you before you order. Start with this page to request a quote for TOPCon cells or a custom panel. To compare other formats first, browse loose cells sorted by technology and size.