5-Min Battery Health Check

A battery can look perfect on the outside but be at the end of its life on the inside.

1. The Visual Test

Look for dents, cracks, or swelling in the casing. Ensure the metal contact points are clean and not blackened.

2. The Diagnostic Shortcut

Most major UK e-bike systems have built-in health checks. For Bosch, press and hold the power button on the battery for 10 seconds; if all 5 LEDs flash, it is generally healthy. For Shimano/Specialized, check the cycle count or health percentage in the app or display.

3. The Turbo Stress Test

Turn the bike to its highest power mode (Turbo/Boost) and ride hard from a standstill. If the battery level dips significantly and bounces back when you stop, the internal resistance is high, indicating a tired battery.

4. The Charger Check

Generic, unbranded chargers from third-party sites are a major fire risk; always ask to see the original manufacturer charger - or a receipt for a compatible charger purchased from a specialist ebike supplier.