A battery left flat or unmaintained over a UK winter is one of the most common — and most avoidable — causes of an expensive spring surprise. Here’s what actually matters.
Don’t store batteries flat
A lead-acid or AGM battery left discharged over winter can sulfate and permanently lose capacity. Lithium batteries are more tolerant but still benefit from being stored at a partial charge rather than fully flat or fully topped up.
Use a maintenance charger, not just a one-off charge
Leaving a smart charger like the NOCO Genius 10 connected through storage keeps the battery topped up automatically without overcharging — it steps down to a maintenance mode once full rather than continuing to push current in.
Protect your electronics too
Remove handheld and portable units for indoor storage where practical, and disconnect fixed-mount displays from power if the boat sits unused for months — reduces both parasitic battery drain and condensation risk in connectors.
Spring checklist
- Check battery terminals for corrosion before reconnecting
- Test charge level before the first trip, don’t assume it held
- Power on all electronics and confirm GPS/sonar lock before you’re back on the water
Need a maintenance charger or a replacement battery before winter sets in? Browse the shop or ask us for advice specific to your setup.