This article covers common Gen2.5 Battery questions, troubleshooting tips and best practices to help you get the most from your battery and keep it performing at its best.

For instructional video, see: Gen2.5 Battery Tips

Battery Loses 1–2% While Sitting

You may notice that a fully charged battery loses a small amount of charge after sitting unused for several days.

This is normal.

The Gen2.5 Battery has an active BMS and Bluetooth system, which consume a very small amount of power while the battery is sitting.

The battery may therefore drop by a small percentage over time.

If you're only trying to top up the final 1–2%, the charger may consider the battery already fully charged and not restart the charging cycle.

Battery Difficult to Remove

Some board and mast combinations can place additional compression on the battery, making it slightly harder to remove.

This can happen because different boards and mast systems vary in shape, stiffness and surface area.

If this happens:

Method 1 – Use the Battery Latches for Leverage

1. Open both battery latches.
2. Place your thumbs inside the latch recesses.
3. Hold the latches with your fingers.
4. Use the latches to gently push the battery away from the unit.

This provides much better leverage than simply trying to pull the battery straight out.

Method 2 – Reduce Compression

If the battery is still difficult to remove, slightly loosen the front mast bolts by one or two turns.

Reducing the compression can allow the battery to slide out more easily.

Important: Only loosen the bolts enough to release the compression. Do not operate the system with the mast bolts loose.

This issue is generally related to the specific combination of board, mast and Foil Drive installation rather than a fault with the battery.

For instructional video, see: Removing Battery from Housing Tip

40V Battery Checker Shows the Wrong Percentage

The original Gen 2 inline battery checker is not compatible with 43V batteries.

Gen2.5 batteries use a higher battery voltage, the older checker will display an incorrect state of charge.

Instead, check battery percentage using one of these methods:

• The Battery Caddy
• The Foil Drive App
• The Foil Drive unit when connected

These methods provide the correct battery state-of-charge information for Gen2.5 Batteries.

My Battery Got Wet

If water enters the battery compartment, don't panic.

The most important thing is to remove the water, dry the connectors and protect them from corrosion before continuing to use the system.

The battery and unit are designed to be waterproof, but the electrical connectors require particular care.

If Salt Water Entered the Unit

Salt water should be removed as soon as possible because salt residue can accelerate corrosion and damage electrical terminals.

1. Remove the battery.
2. Drain all water from the unit.
3. Rinse the battery compartment thoroughly with fresh water to remove any salt residue.
4. Allow the unit to drain and dry.
5. Dry the battery connector thoroughly.
6. Inspect the terminals for any signs of corrosion.

1. Once dry, reapply Foil Drive dielectric grease to the battery terminals.
2. Allow everything to dry before reinstalling the battery.

Do not continue operating the system with salt water sitting inside the unit or on the electrical connectors.

If Fresh Water Entered the Unit

Fresh water is much less of a concern.

Simply:

• Remove the battery.
• Drain the water.
• Allow the compartment to dry.
• Dry the battery connector.
• Reapply Foil Drive dielectric grease.
• Reinstall the battery once everything is dry.

Battery Damaged by Water or Impact

If there is any damage to the battery heat shrink, outer casing or connector, do not use or attempt to charge the battery.

Contact the Foil Drive Support Team at [email protected] with clear, detailed photos of the battery so we can assess the damage.

Preventing Water Ingress

If you're regularly finding water inside the unit, there are several things to check:

• Ensure the O-ring is correctly installed.
• Check that the O-ring is clean and free from sand, dirt or debris.
• Check that the battery latches are correctly fitted and in good condition.
• Check for damage to the unit or sealing surfaces.
• Check that your board is sufficiently rigid for the Foil Drive installation.

Board Flex

Some boards may flex significantly under load.

If the board is too flexible, the movement of the board can place additional forces on the more rigid Foil Drive unit. During impacts or landings, this movement can momentarily affect the seal and allow water to enter the battery compartment.

If you're experiencing repeated water ingress, check the rigidity and compatibility of your board and Foil Drive setup.

Need More Help?

If you've worked through these troubleshooting steps and are still experiencing battery issues, please contact the Foil Drive Support Team.

When contacting support, include:

• Your Gen2.5 Battery model
• A description of the issue
• Photos showing the battery and connectors where relevant
• A video showing the charger behaviour and indicator lights, if the issue is related to charging

This information will help our support team diagnose the issue as quickly as possible.