Battery died somewhere unsafe?
If the car's stopped in traffic or on a freeway, get everyone out to a safe spot well away from the road, turn on the hazard lights and call roadside assistance if you have it. If anyone is hurt or in danger, call 000. Leave a battery alone if it's cracked, swollen or leaking.
Why Melbourne batteries give out in winter
Cold slows the chemical reactions inside a battery, so it has less to give at the very moment a cold engine needs more to turn over. RACV says batteries are more likely to fail in winter and through long cold spells, and its patrols attended 275,760 battery callouts across Victoria in 2025.
Summer does its share of the damage. Melbourne's hottest day on record reached 46.4 degrees C, on 7 February 2009, and NRMA says extreme heat or cold can shorten a battery's life. Heat wears a battery down quietly, and the first cold snap is often when you find out.
What Melbourne driving does to a battery
Short hops across the suburbs
RACV says trips under 20 minutes don't give the alternator time to recharge the battery. A week of school drop-offs and runs to the shops can leave it low all the time. RACV's advice is at least 20 minutes of driving each week.
Living on the street
RACV suggests a garage over the street where you can, especially overnight and in high winds. If the car sleeps at the kerb, a test before winter matters more, and RACV also mentions a battery blanket as a way to keep the battery warm.
The cold cranking number
RACV says to check a battery's CCA rating (cold cranking amps), which shows how well a fully charged battery copes with the cold. NRMA adds that a replacement must be the right size and type, with the posts in the right place.
Just bought from a Victorian dealer?
Consumer Affairs Victoria lists batteries among the items the statutory warranty on a used car doesn't cover. A battery test at the first service tells you where you stand.
Is it the battery or the alternator?
A new battery won't fix a weak alternator. It just goes flat the same way. RAA says a battery light on the dash usually comes down to the car's electrical system, so the mechanic should test the charging side before selling you anything.
The type matters on newer cars too. RACT says modern cars need the correct battery technology, whether that's calcium, EFB, AGM or lithium, and that some European cars hide a second battery. NRMA says a car with start-stop needs a battery built for those heavier loads.
What the mechanic should tell you before fitting one
- The test result for the old battery and for the alternator.
- Which type the car needs, and why that one.
- Whether the car needs a reset or battery registration once it's in.
- How long the new battery's warranty runs, written on the invoice.
- That the old battery is going to recycling.
Where we'd start
Before winter, we'd get any battery over three years old tested, especially if the car mostly does short trips and sleeps on the street. If it fails, we'd fit the type the maker specifies with a CCA rating to match, not whatever fits the tray. Stop-start or a European badge? Put it in the card so the right battery turns up with the mechanic.