Cylindrical Li-ion 3.6V · Available Today
18650.
21700.
The cylindrical cells that high-drain devices were designed for.
3.6 V Li-ion cells with protected button-top construction, up to 8 A continuous discharge, and capacities up to 18,000 mWh. Built for flashlights, vapes, e-bikes, power tools, and anything else that drains a cell harder than alkalines can survive.
Why SCIGOLD Cylindrical
What every cell in this series shares.
True Li-ion chemistry. Three times the energy density of NiMH at the same size.
High-performance variants sustain 8 A — enough for flashlights, vape mods, and power tools.
On-cell protection circuit for over-charge, over-discharge, short-circuit, and over-current.
Rated cycle life to 80% capacity retention under IEC 61960-3. Roughly 5× the lifespan of an alkaline alternative over the same usage.
Built For
The devices alkalines die in.
18650 and 21700 are the cells inside everything from your Tesla pack to your tactical flashlight. Here's where SCIGOLD's lineup lives in the consumer world.
01 · Tactical & Outdoor Lighting
Cut Through The Dark.
Surefire. Olight. Fenix. Nitecore. ThruNite. The premium flashlight industry runs on 18650.
Sustained 8 A discharge means flashlights stay at full brightness instead of dimming as the cell drains. Our cold-weather variant holds capacity down to -20°C — built for winter EDC, search-and-rescue, and hunting in sub-freezing conditions.
02 · Sub-Ohm Vape Mods
The 8-Amp Standard.
Sub-ohm regulated mods pull 6–8 A continuous. Mech mods can spike past 20 A.
Most "rechargeable" 18650 cells venting on vape forums are budget cells run past their rated discharge. SCIGOLD's high-performance 8 A 18650 has the IR (internal resistance) and current rating to drive serious clouds without sagging — and a built-in protected button top in case of accidental short.
03 · E-bike & E-scooter Packs
Rebuild The Pack.
Skip The OEM Markup.
21700 is the modern standard. Tesla, Rivian, Lucid — and most e-bike OEMs since 2021 — switched from 18650.
Same form-factor philosophy as 18650, just 20% larger by volume — and 40% more energy. The same DIY community that rebuilds Bafang and Bosch e-bike packs uses 21700s for the upgrade because the BMS and welding patterns translate directly. SCIGOLD's 18,000 mWh 21700 hits the consumer sweet spot.
04 · Cordless Power Tool Rebuilds
Save $100. Keep The Tool.
Cordless drills, impact drivers, leaf blowers — the tool still works. The pack just died.
DeWalt, Makita, Milwaukee, Ryobi 18 V packs are built around 18650 cells. After 3–5 years the worst cell in the pack drops voltage and the BMS shuts everything down — but the rest are fine. Open the pack, replace the dead cells with SCIGOLD 3,500 mAh 18650, spot-weld, close. The tool gets a second life for a tenth of the replacement-pack price.
And dozens more · the cylindrical Li-ion ecosystem
Drones · RC vehicles
High-discharge 21700 packs · sustained current under load
Robot vacuum rebuilds
Roomba, Roborock 18650 pack replacements
Camping headlamps
Petzl, Black Diamond, Fenix HL series
Hunting · EDC flashlights
Premium 18650 cells · sustained 8 A discharge for high-lumen output
Ham radio · GMRS
Baofeng, Yaesu, Icom handheld packs
Medical devices
Otoscopes, dental curing lights, portable diagnostics
Lab & field test gear
Multimeters, oscilloscopes, GPS receivers
Audio · video production
Wireless mics, on-camera LED panels, recorders
Shop the Series
3 cells. 1 charger. Pick by what you're powering.
The Companion Charger
One charger. Every cell in this series.
CW401 Smart Charger
Scigold 18650/21700/Li-ion Battery Charger with LCD Display
LCD display, 18650 / 21700 / Li-ion compatibility, 4 independent slots. Works with every cell in this series — and most cylindrical Li-ion cells on the market.
Picking By Size
Two cell sizes. Different jobs.
| Cell size | Dimensions | Capacity range | Typical use |
|---|---|---|---|
| 18650 | 18 × 65 mm | 2,000 – 4,000 mAh / 7,200 – 14,400 mWh | Flashlights · vapes · DIY packs |
| 21700 | 21 × 70 mm | 4,000 – 5,000 mAh / 14,400 – 18,000 mWh | E-bikes · scooters · modern flashlights |
Tested and certified
The SCIGOLD Catalog
Two more series to explore.
AA 1.5V Series
4,440 mWh AA + Smart Case →
Regulated 1.5V lithium AA, LCD smart charging case, USB-C input. The next AA — not the next NiMH.
USB-C Cables
60W Silicone → 240W Magnetic →
Three power tiers, four product lines. Liquid-silicone nightstand cables, braided 240W flagship, magnetic break-away.