How to store an EV for winter (or any extended period)

The challenge of EV long-term storage

Lithium-ion batteries self-discharge over time, and if the battery drops to near-zero charge while sitting, it can suffer permanent capacity loss. Extreme temperatures (hot or cold) accelerate this. Storing an EV correctly for 1–4 months takes 15 minutes of preparation.

Optimal storage charge level

Store the battery at 50% charge for extended storage. This is the chemical 'rest point' for lithium-ion cells — neither fully charged (which stresses the cathode) nor fully discharged (which can damage the anode). 40–60% is a safe range. Do not store at 100% or below 20%.

• ·Target: 50% state of charge (40–60% acceptable)
• ·Not 100%: high SoC accelerates cathode stress in storage
• ·Not below 20%: risk of cells dropping to damaging low voltage
• ·Check level monthly if storing for over 30 days

Temperature matters

Store in the most temperature-stable environment available. An attached garage is better than outdoors; a climate-controlled space is best. Extremes above 95°F or below 14°F (-10°C) accelerate self-discharge and can stress thermal management systems even when parked.

Trickle charging option

Some EVs support a 'storage mode' or trickle Level 1 charge that maintains the battery at the target level automatically. Check your manufacturer's app — Tesla, Rivian, and Hyundai all have this. If available, plug into Level 1 (120V) and set the charge limit to 50%: the car maintains itself.

Before returning to use

Check tire pressure (cold storage deflates tires), inspect brakes (they may have light surface rust after weeks of disuse — normal, disappears after first few stops), and check that the 12V auxiliary battery is charged. Run through a normal Level 2 charge cycle before your first long drive.