Vapcell F54 21700 Rechargeable Battery – 5400mAh with Flat Positive Terminal

The Vapcell F54 is a high-quality 21700-type lithium-ion rechargeable battery cell with a capacity of 5400mAh and a maximum discharge current of 10A. It is manufactured in China and is suitable for a wide range of devices, including tactical and camping flashlights.

This model features a flat top, making it compatible with flashlights designed for batteries without a protruding contact.

Technical Specifications

Specifications	Value
Type	21,700 INR
Model	F54 with a flat plus
Rated Capacity	5,400 mAh
Minimum capacity	5,250 mAh
Rated voltage	3.6 V
Maximum discharge current	10 A
Voltage at the end of charging	4.20 V
Voltage at the end of the discharge	2.5 V
Normal charging current	2000 mA
Fast charging current	5,000 mA
Elevation	70.5 mm
Diameter	21.1 mm
Weight	72 years
Material	Lithium-ion cell

Batteries with or without protection—what's the difference?

Protected batteries have an additional circuit board that protects against overcharging, over-discharging, and excessive current. They usually have a raised positive terminal and are slightly longer than standard batteries. They are suitable for flashlights from brands such as Acebeam, Olight, Fenix, Nitecore, and Armytec.

Unprotected batteries, such as the Vapcell F54, have a flat positive terminal and standard dimensions. They are suitable for flashlights designed specifically for this type of cell—including models from Dulotec.COM.

The surest way to choose the right battery is to measure the dimensions of the original one and compare them with the technical specifications of the new one. If needed, you can contact us for advice.

Instructions for Use

Charge the battery using a high-quality lithium-ion charger before using it for the first time.
Operating temperature during charging: 0°C – 45°C; during discharging: -20°C – 75°C.
Storage temperature: -5°C to 35°C.
Do not throw into fire or water—risk of fire or explosion.
Do not crush, strike, or disassemble the battery.
Keep out of reach of children.
If the device has not been used for an extended period (more than 3 months), charge the battery before use.
The battery gets hot during use—handle with care after use.

Safety Rules

Do not modify, puncture, or short-circuit the device.
Do not expose to water, fire, or extreme temperatures.
Do not use in defective devices.
Do not overcharge or over-discharge the battery.
Do not charge at sub-zero temperatures.
Do not use a battery with a damaged foil.
Store in a protective case—never in a pocket or bag without one.

Frequently Asked Questions

What is the difference between a battery with a flat positive terminal and one with a raised positive terminal?

Flat-top batteries do not have a protruding positive terminal. They are suitable for devices designed specifically for this type of cell. Button-top batteries have a small protruding tab, which is necessary for some flashlights with a spring-loaded contact. The Vapcell F54 is a flat-top model. Before purchasing, check which type your device requires.

What types of flashlights is the Vapcell F54 battery suitable for?

The Vapcell F54 is an unprotected battery with a flat positive terminal. It is suitable for flashlights designed for standard 21700 cells without a protection circuit. Flashlights requiring higher current or standard sizes are well-powered by this cell. If you’re unsure, measure the battery compartment in mm and compare it to the F54’s dimensions: 21.1 mm in diameter and 70.5 mm in height.

What kind of charger should I use to charge a 21700 battery?

You must use a high-quality charger that is compatible with lithium-ion cells and the 21700 format. The normal charging current is 2000 mA, and the fast charging current is up to 5000 mA. Do not use chargers designed for other battery chemistries or those that do not support voltages up to 4.20 V. Charge only at temperatures between 0°C and 45°C.

Is it safe to carry a 21700 battery in my pocket or bag?

No. Lithium-ion batteries should not be carried unprotected in a pocket or bag. Metal objects can cause a short circuit, which is dangerous. Always use a special protective battery case when transporting and storing them. This is one of the basic rules for safe use.

What is the operating temperature of the Vapcell F54?

During charging, the battery operates within a range of 0°C to 45°C. During discharge (active use), the range is much wider—from -20°C to 75°C. A temperature between -5°C and 35°C is recommended for storage. Avoid exposure to extreme temperatures, as this reduces the battery’s lifespan and can be dangerous.

How can I tell if my battery is dead and needs to be charged?

The end-of-discharge voltage for the Vapcell F54 is 2.5 V. When the voltage drops to this level, the battery is depleted and must be recharged. Many chargers display the current cell voltage. Do not allow the battery to discharge below 2.5 V, as this will cause permanent damage to the battery.

What should I do if the battery hasn't been used for a long time?

If the battery has not been used for more than 3 months, charge it before use. Lithium-ion cells slowly self-discharge over time. Long-term storage in a fully discharged state can lead to a permanent reduction in capacity. It is recommended that you store the battery at approximately 50% charge in a cool, dry place.