Battery life

Sabre Man

I think my battery is going. I tried recharging it, but when I did all lights but one on the charger came on (and it WAS totally dead). It's only 5 years old.

What's the average life expectancy of a car battery?

bazz26

Generally you only get a 12 month guarantee with a new car battery. They are like light bulbs in that they can go at any time.

If you got 5 years out of one then you really cannot complain.

crosstownk

I'd agree with bazz, 5 years is good enough. I've seen plenty of batteries last a lot a longer than that though.

Try reacharge it overnight. Sometime a quick charge will not fully replenish a battery.

rebel.ranter

Strange, I have had the same battery for six years & it looks like it has been there for a few years before that. And this is in a car that is seldom used (especially now with the weather, it's a convertible).

Del2005

The life of a battery is like all consumables on a car. Depending on driving style and usage are all a big factor. Also if it is only happening recently may be a charging issue with the car. How long/often do you drive the car? If it's mainly short journeys the battery will discharge as it never gets a decent run.

Max_Damage

The battery in my car has been in it since 1999, and it still holds the charge well.

It's an Exide battery. I think they're known for good quality batteries anyway.

Lex Luthor

my battery is same from new...almost 7.5yrs old now

Sabre Man

Del2005 wrote:

The life of a battery is like all consumables on a car. Depending on driving style and usage are all a big factor. Also if it is only happening recently may be a charging issue with the car. How long/often do you drive the car? If it's mainly short journeys the battery will discharge as it never gets a decent run.

I drive fairly long journeys (at least 1 hour), but very infrequently (convertible, bad weather, second car). This is at least the second time I've had to change battery on this car during the 10 years I've had her, and I used to drive a fair bit before I bought the other one.

How long does it take for a battery to go from full to flat if the car isn't used?

I always expected a battery to last more than 5 years. My parents used to have Corolla whose battery lasted about 10 years.

crosstownk

Sabre Man wrote:

How long does it take for a battery to go from full to flat if the car isn't used?

It depends. I've seen batteries go flat after a week left at the airport. I've also had cars in the garage here that have been left lying up for months and still started on the first turn.

A lot depends on how much drain is on the battery (alarms, accessories) when the car is switched off. It also depends on the brand of battery to some extent and what the state of charge is at the time the engine is switched off.

barthek

You might as well have very minor short circuit in the car which discharges battery in full, or some electronic device which need a decent amount of power (alarm, radio?).

You could also use multimeter to see what amperage it takes when all is off.

Sabre Man

No alarm. The stereo is of the type where you remove the unit when you leave the car, which I always do.

There shouldn't be anything draining the battery while the car isn't being used.

The only thing is the interior lights come on when I open the doors, but I don't usually tend to leave them open for long.

barthek

well i guess that if you get a new battery and be back here in a couple of weeks/months then you will know that something must have been wrong with power drainage

Del2005

Just because you take the front off the radio doesn't mean there is no power going into it. If it has a clock that'll need power. Even the clock in the car would take power. Does the car have a power roof, again that could be drawing power? Also if it has a power roof and the only time you use the car is in good weather with the top down, then you are placing a very heavy load on the battery when starting the car and it may need longer to recharge.

If you don't want to drain the battery when the car isn't being used just disconnect it and then there definitely won't be any drain on it.

daedalus2097

crosstownk wrote:

Try reacharge it overnight. Sometime a quick charge will not fully replenish a battery.

Good advice. A good overnight charge with a mains charger is better for the battery than a decent drive... Power from a charger is a lot more regulated and smoother than that from an alternator. A well treated battery of a good brand will generally last longer than 5 years, but yours probably isn't being treated well at all. Particularly bad for a battery is being left in a run down state - if you've left the car for months on end and the battery's flat, it could have been flat for ages, and a flat car battery basically eats its own innards over time...

Sabre Man

Del2005 wrote:

Just because you take the front off the radio doesn't mean there is no power going into it. If it has a clock that'll need power. Even the clock in the car would take power. Does the car have a power roof, again that could be drawing power? Also if it has a power roof and the only time you use the car is in good weather with the top down, then you are placing a very heavy load on the battery when starting the car and it may need longer to recharge.

If you don't want to drain the battery when the car isn't being used just disconnect it and then there definitely won't be any drain on it.

There's no clock. The hood is powered, but surely it doesn't drain power when the car is just sitting there?

I hear what you're saying about placing a heavy load on the battery by only using the car with the hood down. Would a 1-2 hour drive not make up for the power drain of taking it down?

Looks like I'm better off by just removing the battery when I'm not using the car, which isn't much at the moment due to our horrible summer weather.

Thanks for all replies

JHMEG

5 years is to be expected, but 8 or so is not unheard of.

Most new batteries will come with a 3 year warranty, some will come with 4 (eg Halfords calcium). Some cheapo ones will come with only 2.

crosstownk

JHMEG wrote:

5 years is to be expected, but 8 or so is not unheard of.

my 1989 Passat went to the grave with it's original battery.............in 2000. And the 2000 VW Bora that replaced it still has the VW Transporter battery that I fitted 2 months after delivery.