Samsung 18650 35E – a reliable, high-capacity lithium-ion battery

The Samsung 18650 35E battery is a high-quality INR 18650 lithium-ion battery with a rated capacity of 3400mAh. It is suitable for a wide range of devices—flashlights, headlamps, and other tactical gear.

This model features a flat-plus design and is engineered for stable operation at a continuous discharge current of up to 8 A and a peak current of up to 13 A.

Technical Specifications

Specifications	Value
Type	18,650 INR
Brand	Samsung
Model	35E with a flat plus
Rated Capacity	3,400 mAh
Minimum capacity	3,350 mAh
Rated voltage	3.6 V
Voltage at the end of charging	4.20 V
Voltage at the end of the discharge	2.5 V
Maximum continuous discharge current	8 A
Maximum instantaneous discharge current	13 A
Normal charging	1,000 mA
Fast Charging	2000 mA
Elevation	64.9 mm
Diameter	18.3 mm
Weight	50 g

A battery with or without protection—what's the difference?

Protected batteries contain a small circuit board embedded in the anode or cathode. It protects the cell from overcharging, over-discharging, and excessive current—when a limit is reached, the circuit automatically shuts off.

Protected batteries are suitable for flashlights with mechanical reverse-polarity protection—a feature common to brands such as Acebeam, Olight, Fenix, Nitecore, and Armytec. However, they are not compatible with flashlights such as Zebralight and Dulotec, which are designed specifically for unprotected batteries.

The protected batteries are physically slightly longer and wider than the standard ones
They are not suitable for all flashlights—some require a higher current or standard sizes
To make the right choice, measure the size of the original battery in mm and compare it with the technical specifications
If you have any questions, please contact us—we'll help you find the right battery for your device

Safety Rules for Use and Storage

Improper use or storage may result in a fire or explosion. Follow these guidelines:

Do not alter, modify, disassemble, puncture, cut, or crush the battery, and do not cause a short circuit
Do not expose to water, fire, or high temperatures
Do not use in defective devices
Do not overcharge or undercharge; do not charge at sub-zero temperatures
Do not use the battery if the foil is damaged
Do not store in a pocket or purse—use a protective case

Frequently Asked Questions

What is the difference between the Samsung 35E and the 30Q?

The Samsung 35E is optimized for high capacity—3400mAh—while the 30Q is designed for a higher discharge current. The choice depends on the device’s needs. If long runtime is a priority, the 35E is the more suitable battery. If the device requires a very high current, the 30Q may be the better option. Check the specifications of your flashlight or device before making a choice.

Is the Samsung 35E compatible with Dulotec flashlights?

Dulotec flashlights are designed for unprotected batteries. The standard, unprotected version of the Samsung 35E is fully compatible with these flashlights. It is important to check the exact model of the flashlight and its battery requirements. If in doubt, you can contact the Dulotec.COM team for additional assistance. It is also recommended that you measure the dimensions of the battery compartment.

What kind of charger is suitable for the Samsung 18650 35E?

Normal charging requires a current of 1000mA, while fast charging requires 2000mA. It is recommended to use a high-quality charger compatible with the INR 18650 format. The charger must support a charging voltage of up to 4.20V. Avoid cheap chargers without overcharge protection. Good chargers automatically shut off when the battery is fully charged.

How do I properly store a Samsung 18650 battery?

The battery should be stored in a special protective case, away from moisture, fire, and direct sunlight. Do not place it in a pocket with coins or metal objects. Avoid storing it at sub-zero temperatures or in a highly humid environment. Do not store the battery fully discharged for an extended period of time. It is recommended that the charge level be around 50% during storage.

What is the difference between a battery with and without protection in the 18650 format?

Batteries with a built-in protection circuit are slightly longer and wider than standard ones. They have a circuit that shuts off the battery in case of overcharging, over-discharging, or excessive current. Batteries without protection are more compact and better suited for devices that require high current. Not all flashlights are compatible with the longer, protected batteries. Check the device’s manual or consult the seller.

How can I tell which battery is right for my flashlight?

The easiest way is to measure the dimensions of the original battery in millimeters and compare them with the technical specifications of the new one. Also check whether the flashlight supports batteries with or without protection. Many manufacturers include this information in the user manual. If you’re unsure, contact the Dulotec.COM team—they’ll help you choose the right option. Never insert a battery with the wrong dimensions.

Is it safe to use a battery with a damaged foil?

No—a battery with a damaged or compromised foil must not be used under any circumstances. The foil serves a protective function and prevents contact between the cell and metal surfaces. Damaged foil can lead to a short circuit, overheating, or even a fire. If you notice any damage, dispose of the battery properly. Do not attempt to repair the foil yourself.