21700 BASEN 4000MAH 3.7V 30A BATTERY

21700 BASEN 4000MAH 3.7V 30A BATTERY keeps your device safely powered. Always use the correct battery and charger for your device. Order from Vapes Direct Wholesale for fast UK dispatch, free UK delivery on orders over £30 and trade pricing for UK vape shops.

Basen 21700 4000mAh 3.7V 30A Battery

A high-capacity 21700 lithium-ion cell from Basen, rated at 4000mAh with a 30A continuous discharge. That combination is what makes it a favourite for sub-ohm vapers — the capacity gets you through a full day, and the 30A rating gives real headroom for low-resistance builds.

Supplied as a bare cell for use in 21700-compatible regulated mods and external chargers. The higher discharge rating makes it a sensible choice for high-wattage devices where a lower-rated cell would sag under load.

Features

• 4000mAh capacity for genuinely long runtime
• 30A continuous discharge rating
• 3.7V nominal output
• Built for high-wattage sub-ohm devices
• Sold as a bare cell for external charging

Battery Safety — Please Read

• Use a dedicated Li-ion charger and never charge unattended.
• Always carry cells in a battery case, never loose.
• Inspect the wrap before each use — re-wrap or retire any damaged cell.
• Use matched pairs in dual-battery mods and charge them together.
• Never build below the resistance your cell's 30A rating safely supports.
• Retire any cell that swells, gets hot in use, or has been dropped hard.

FAQs

Q: What does the 30A rating actually mean?
A: It is the maximum continuous current the cell can safely deliver. Lower-resistance coils pull more current, so the rating sets a floor on how low you should build.

Q: Will it fit my 18650 mod?
A: No. A 21700 is larger in both dimensions and will not fit an 18650-only device.

Q: Is the higher capacity worth it over a 3000mAh cell?
A: If you vape at high wattage, yes — the difference in time between charges is noticeable.

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For adults aged 18 and over only. We use age verification at checkout. All products are TPD/TRPR compliant and notified to the MHRA.