Can a car battery just "die"?

[BraveSirRobin]

My car (SEAT Leon 1.4) suffered a complete shutdown on the way into work this morning. Engine just stopped dead then electrics went haywire - warning lights flashing on and off, hazards working/not working, etc. Luckily I have roadside assist - AA turned up and diagnosed a dead battery. Fitted a new one and all back to normal. But ... it was serviced & MOT'd yesterday! Phoned the garage - they've looked through the work that was done and confirm the battery was tested and it was all good.

Can a battery just fail like that with no apparent warning? Car was running completely as normal before it died.

For those that know this area - breakdown happened in Sonning in the middle of rush hour! This made me very unpopular. Apologies to anyone who was late because they had to navigate round a black SEAT with the bonnet up (apart from the 3 numpties in SUVs who pulled right up behind me and then had to reverse to get round when they realised I'd broken down!).

Edited by BraveSirRobin on Tuesday 17th October 13:01

[Easternlight]

Possibly if the structure of the battery failed inside eg plates collapsing or shorting out then the voltage would suddenly drop.

[Tony1963]

When I worked in Saudi this was the way all car batteries died, and usually between one and two years old. The heat murdered them. In my last car, I drove to a hardware store, parked up and went in. Less than five minutes later I came out, plopped the remote… nothing. Managed to bump start it and drove it straight to the dealership for a replacement. Incredible.

[520TORQUES]

Yes they can and they do.

[stevieturbo]

Usually there will be some symptoms, whether or not they were noticed is another matter

[stevemcs]

Yes they can and now is the time of year when they start to fail

[Megaflow]

Yes they can. My wife’s second car was a Saxo VTR and she was very proud of it. She went to visit her mum who lived in a less than glamorous part of town so she went to put it her garage when she went to visit. One day she parked up, went into get the garage key, came out to move it and it wouldn’t start. I came with some jump leads and tools, it wouldn’t jump start so I started to do some tests and found no voltage at the starter solenoid, so we bump started it and she drove it home. Got home and with more tools available I found voltage at the solenoid, but only 6 volts. Went and got the battery tested. Dead. It went from being capable of a cold start to absolutely dead in 10 miles

[Sheepshanks]

The examples given are all cars that failed to start - OP’s case is different as he was driving.

[Polly Grigora]

Sheepshanks said:

The examples given are all cars that failed to start - OP’s case is different as he was driving.

Spot on

but

Alternator would have kept the electrics powered up until it possibly failed due to uncontrolled voltage issues

As long as the alternator is working as should be there is no way the car should have stopped running

or

Battery died - Alternator kept electrics up and running - Engine later cut when running at tick-over at lights or in traffic due to alternator output being too low to cover electrical loads

[tux850]

Polly Grigora said:

Alternator would have kept the electrics powered up until it possibly failed due to uncontrolled voltage issues

As long as the alternator is working as should be there is no way the car should have stopped running

Agreed. In the scenario described whilst I wouldn't be ruling out the battery I would be first suspecting an alternator issue. The (flat) battery could be a symptom rather than the cause.

[tapkaJohnD]

I had a similar scenario with a Citroen C5. Engine never failed, but the electric 'hand' brake stuck on!
Thanks to RAC's Technical experts who fixed it by phone (Press down HARD on the footbrake, release the handbrake lever three times, repeat ten times! I know, it's black magic!)

But electrical probs persisted, and dealer diagnosed failing battery (three years old). After the hand brake problem recurred, they said alternator - problem fixed.
Check your alternator, OP!
John

[E-bmw]

I too had similar with an old bm several years ago.

Alternator belt failed, light came on, then went out a few mins later (turns out the bulb blew) so I continued & thought nothing of it, few days down the line car just cut out & displayed all signs of flat battery, which of course it was.

It was only then that I saw the shredded belt.

[Polly Grigora]

Tony1963 said:

When I worked in Saudi this was the way all car batteries died, and usually between one and two years old

People were constantly swapping old for new over there, was a good fiddle for some. Anyway many of the batteries were crap from new

Another problem was that many when being called for prayer time would pee in a new dry charged battery rather than waste time in having to walk far to a toilet

There were others that stored their home-made wine in dry charged batteries, fooled the police and destroyed the Roman Empire

In a dodgy country dodgy things do happen