Winter Storage Done Right

As the colder months approach, many car owners face the challenge of storing their vehicles for extended periods. Whether it's a classic car, a summer convertible, or simply a second vehicle, proper storage ensures your car will be in good condition when spring arrives. A critical component to focus on during storage is the 12V battery, which can suffer if neglected. This guide will walk you through preparing and maintaining your battery for winter storage, along with the importance of using CTEK chargers to keep it in peak condition.

1. Why battery maintenance is key

When a vehicle remains idle for months, the 12V battery gradually discharges. Without proper care, the battery can lose its charge completely, leading to sulfation—a buildup of lead sulphate crystals that can permanently damage the battery and shorten its lifespan. To avoid this, it’s crucial to prepare your battery correctly and ensure it’s maintained throughout the storage period.

2. Prepping the battery for storage

Before storing your car, take these essential steps to ensure your 12V battery is ready for the winter hibernation:

  • Clean the battery terminals: Dirt and corrosion on the terminals can create resistance and make it harder for the battery to maintain its charge. A simple mixture of baking soda and water can be used to clean the terminals, followed by applying a terminal protectant to prevent future corrosion.
  • Check the battery’s charge: Ensure the battery is fully charged before storage. A fully charged battery will have a voltage reading between 12.6 and 12.8 volts. If necessary, use a charger to bring it to full charge before storing.

3. The importance of charging during storage

One of the most effective ways to ensure your battery remains in optimal condition during storage is by using a charger, such as those from CTEK. CTEK chargers are designed to maintain the health of your battery throughout the winter months, ensuring it’s ready for use when the warmer weather returns.

  • CTEK's smart charging technology: Unlike traditional chargers, CTEK’s chargers are equipped with smart technology that automatically adjusts the charging process based on the battery’s needs. This prevents overcharging, which can damage the battery, while also ensuring it remains fully charged during extended storage periods.
  • Maintenance charging: CTEK chargers feature a maintenance mode, which is crucial for keeping the battery topped off without risking damage. These chargers can be left connected for months, keeping the battery healthy and prevent deep discharge.

4. Using a CTEK battery charger

For long-term storage, investing in a battery charger, such as the CTEK CT5 TIME TO GO, is an ideal solution. These devices ensure your battery stays fully charged and protected throughout the winter:

  • Prevents overcharging: CTEK’s smart chargers regulate the charge, ensuring the battery is maintained at an optimal level without overcharging.
  • Protects against sulfation: By keeping the battery topped off, CTEK chargers prevent sulfation, which can occur when the battery is left in a deeply discharged state for too long.
  • User-friendly: With clear indicators and automatic settings, CTEK chargers are easy to use, making them a worry-free option for battery maintenance.

5. Where and how to store the car and battery

In addition to keeping your battery charged with a CTEK charger, where you store your car also plays a key role in preserving the battery.

  • Indoor storage: Whenever possible, store your car in a dry, temperature-controlled environment like a garage. Cold temperatures can slow down the battery’s internal chemistry, reducing its ability to hold a charge.

6. Preparing for spring

Once winter is over, and it’s time to bring your car out of storage, your 12V battery should be in excellent condition if properly maintained. Here’s how to get it ready for use:

  • Reconnect the battery: If you disconnected or removed the battery, carefully reconnect it, making sure the terminals are clean and corrosion-free.
  • Check the charge: Before starting the vehicle, use a CTEK charger to check the battery’s charge level. If necessary, give it a final boost to ensure it’s fully charged and ready to go.
  • Inspect for corrosion: After months of storage, inspect the terminals again for any signs of corrosion and clean if necessary.

Properly storing your car for the winter involves more than just parking it in the garage and walking away. By taking the time to maintain your 12V battery using CTEK’s chargers, you can ensure that your vehicle will start up easily and perform well when spring arrives. A little preparation now will save you from costly repairs and replacements later. Keep your battery charged, your car protected, and enjoy peace of mind all winter long.

More from CTEK Magazine

Talking cars, charging and camaraderie in a Camaro

CTEK partnerships director Brian Dowdy and Audrain Automobile Museum's Steve Marsocci hit the Californian roads in a 1970 Chevrolet Camaro RS/SS to celebrate a new partnership – and talk cars, charging and camaraderie.

Talking cars, charging and camaraderie in a Camaro

CTEK helps players charge forward at Beyond Skiing Golf

Lots of fun and some great shots were enjoyed at the 2026 Beyond Skiing Golf day as 22 teams enjoyed entertainment and a round of golf at the Dalsjö Golf Club.

CTEK helps players charge forward at Beyond Skiing Golf

CTEK's five-point plan to boost EVs in Sweden

CTEK's Stefan Gabrielsson and Mattias Goldmann of the 2030 Secretariat outline five concrete proposals in Dagens Industri to boost electric car adoption in Sweden.

CTEK

CTEK Launches PRO Series Chargers with Ground-Breaking MODESHIFT™ Technology

CTEK has launched the PRO Series – PRO 1240, PRO 2420 and PRO 2440 – featuring ground-breaking MODESHIFT™ technology that automatically adapts between battery support and intelligent charging for workshops and showrooms.

CTEK Launches PRO Series Chargers with Ground-Breaking MODESHIFT™ Technology

CTEK to Showcase Next Generation of Charging Solutions at Automechanika

CTEK will unveil its next generation of professional workshop chargers, consumer battery chargers, accessories and EV charging solutions at Automechanika – visit us at Hall 8.0, Stand M85.

CTEK to Showcase Next Generation of Charging Solutions at Automechanika

ChargePanel & CTEK: smarter, reliable EV charging

The CEO of white label back-end provider ChargePanel shares how a decade of rapid EV evolution — and a trusted partnership with CTEK — is shaping the future of smart, reliable charging.

ChargePanel & CTEK: smarter, reliable EV charging