SeaLife 7.4V 25Wh Li-Ion Battery: Compatibility and Care

By SeaLife Cameras | Published: 2026-10-23

Category: Buying Guides

Learn which Sea Dragon lights work with the 7.4V 25Wh Li-Ion battery, how to care for it, and when to choose a different battery for your underwater setup.

Quick answer

The SeaLife 7.4V 25Wh Li-Ion battery (product 1776090) is the correct replacement for most Sea Dragon photo/video lights, including the 1200F, 1500F, 2000F, 2100SF, 2300F Auto, 2500F, 3000SF Pro Dual Beam, and 3000F Auto models. It is not compatible with Sea Dragon Mini lights or other brands.

Which lights use this battery?

The 7.4V 25Wh Li-Ion battery is designed exclusively for Sea Dragon lights with a compatible battery compartment. It works with the Fluoro-Dual Beam, 1200F, 1500F, 2000F, 2100SF, 2300F Auto, 2500F, 3000SF Pro Dual Beam, and 3000F Auto models. If you own one of these lights, this battery is the direct replacement you need.

Do not use this battery in Sea Dragon Mini lights (such as the Mini 1200 or Mini 1600) or in lights from other manufacturers. The physical size and connector are specific to full-size Sea Dragon lights, and using it elsewhere could damage the battery or the device.

Battery care for long life

Li-Ion batteries perform best when stored at partial charge (around 50%) in a cool, dry place. Avoid leaving the battery fully discharged for extended periods, as this can reduce capacity. The integrated protective cap helps prevent short circuits when the battery is not in use.

After each dive, rinse the battery with fresh water and dry the contacts gently. Check the O-ring on the light's battery compartment regularly to ensure a watertight seal. If the battery no longer holds a charge or shows physical damage, replace it immediately.

When to consider a different battery

If you own a Sea Dragon Mini light (e.g., Mini 1200, Mini 1600, Mini 1300S), you need the smaller 18650 battery, not this 7.4V 25Wh unit. The Mini series uses a different voltage and form factor. Also, if your light model is not listed in the compatible models above, double-check the manual before purchasing.

For divers who need longer burn times, note that this battery has a 25Wh capacity (3400 mAh). If your dive requires more than 2–3 hours of continuous light, consider carrying a spare battery rather than seeking a higher-capacity single unit, as no larger battery is available for these lights.

Decision rules for buying the SeaLife 7.4V 25Wh Li-Ion Battery

Check your light model: Verify that your light is one of the following: Fluoro-Dual Beam, 1200F, 1500F, 2000F, 2100SF, 2300F Auto, 2500F, 3000SF Pro Dual Beam, or 3000F Auto. If it is not, this battery will not fit. Look for the model number printed on the light body or in the manual.
Do not use in Mini lights: Sea Dragon Mini lights require a different 18650 battery. Using this 7.4V battery in a Mini will not work and may cause damage. If you have a Mini, buy the XTAR 18650 battery instead.
Inspect before each dive: Check the battery for dents, corrosion, or swelling. Ensure the protective cap is intact. A damaged battery should be replaced immediately. A visual check takes 10 seconds and prevents underwater failures.
Store at partial charge: For long-term storage, keep the battery at about 50% charge in a cool, dry place. Avoid full discharge or full charge for extended periods. This extends the battery's usable life significantly.

Product facts

7.4V 25Wh Li-Ion Battery for Sea Dragon Photo/Video Lights: Rechargeable 7.4V 25Wh 3400 mAh Li-ion battery for Sea Dragon lights including Fluoro-Dual Beam, 1200F, 1500F, 2000F, 2100SF, 2300F Auto, 2500F, 3000SF Pro Dual Beam, and 3000F Auto. This confirms exactly which lights accept the battery, so you can be sure it fits your setup before ordering.
7.4V 25Wh Li-Ion Battery for Sea Dragon Photo/Video Lights

Who should buy this battery?

Best for

Owners of compatible Sea Dragon full-size lights (listed above) who need a direct replacement or spare battery.
Divers who want a reliable, UL-listed Li-Ion battery with a protective cap for safe storage.

Not for

Sea Dragon Mini light owners (Mini 1200, Mini 1600, Mini 1300S) who need a smaller 18650 battery.
Users of non-SeaLife lights, as the connector and voltage are proprietary.