Most charging and battery issues are simple to resolve and don't indicate a fault with your battery or charger. Because the Fusion Battery uses a smart Battery Management System (BMS) and communicates with a smart charger, the two devices perform safety checks before charging begins.

This article covers the most common questions and troubleshooting tips to help you identify and resolve charging issues, maintain your battery, and keep your system performing at its best.

Charger Troubleshooting

Charger isn't charging the battery

The Fusion charger is a smart charger that communicates with the battery's Battery Management System (BMS) before charging begins. This "handshake" is a normal safety feature.

Occasionally, if charging is interrupted (for example, the charger is unplugged while charging), the charger may not immediately restart when plugged back in.

Symptoms

• Charger remains solid green.
• Battery does not begin charging.
• Fan does not start.
• Charger appears to have finished charging when it hasn't.

Solution

1. Disconnect the charger from power.
2. Wait 10–15 seconds until:
   • the charger light turns completely off
   • you hear the internal relay click.
3. Reconnect the charger to power.
4. Allow the charger and battery a few seconds to complete their handshake.
5. Charging should begin normally.

When charging starts correctly you will notice:

• the charging indicator begins flashing
• the charger fan starts running.

Tip: Around 99% of charging issues are resolved by fully power cycling the charger before reconnecting it.

Charger flashing red and green

A flashing red and green indicator typically means charging was interrupted unexpectedly, such as unplugging the charger while it was actively charging.

This is simply a charger status indication and is easily resolved.

To reset:

1. Unplug the charger.
2. Wait until all lights have turned off.
3. Plug the charger back in.

The charger will reconnect to the battery and resume charging normally.

Why Won't My Battery Top Up the Last 1–2%?

Fusion batteries use intelligent charging logic.

If your battery is already very close to full, the charger may determine that the charging cycle has already been completed and may not restart for the final 1–2%.

This is completely normal.

Once the battery reaches approximately 50V, it is effectively fully charged. Although the battery can reach around 50.4V, the additional runtime gained is only a matter of seconds and is not worth repeatedly attempting to achieve.

If you're unsure whether charging has completed:

1. Unplug the charger.
2. Wait for it to power down.
3. Plug it back in.

If charging resumes, the battery will top itself up. If not, the battery is already considered fully charged.

Check You're Using the Correct Charge Mode

If charging stops immediately after starting, check whether you've selected Storage Charge.

Storage Charge will stop automatically once the battery reaches the correct storage voltage.

If your battery is already above storage level, charging won't begin.

This is normal behaviour.

Gen 2 Battery Checker Shows the Wrong Percentage

The original Gen 2 inline battery checker is not compatible with Fusion Batteries.

Because Fusion uses 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