Sudden battery failure, non Landy

[Alchad]

Just wanted to check the collective experience on batteries..... my ride on was playing up last week losing power and I was checking over the engine to try and source the problem which required starting it quite a few times over a few days of investigation. Eventually sorted the problem and fired  up to check running OK and gave it a quick ride round the yard to confirm back to full power.Tried to start next day and nothing, figured battery just low so connected up the Noco booster, again refused to start. Swapped battery for one off my other mower and started OK.

Put flat battery on charge overnight, charger showing a red error light, tried again with charger on 'regeneration' again didn't complete charging cycle and measuring voltage gave a fluctuating 7 to 8 volts. So battery obviously gone to the meet it's maker, but just curious as to whether batteries go from seemingly healthy to being the proverbial feet's up dead Parrot?

Alchad

[diffwhine]

I think the technical term is "Donald"...

[Alan Drover]

What type and make and was it a conventional lead acid or an AGM and how old is it?

[BradfordS2]

A few years ago now my Ford focus that I still own and drive every day let me down. I had driven around 15 miles after it starting perfectly for the last 5 or 6 years. Decided to stop at a mini supermarket for a sandwich. Locked up as normal. Came out after 5-10 minutes absolute maximum, car wouldn't unlock on the key. Unlocked it using the manual key and the battery was completely flat. Absolutely nothing in it. Got it jump started from the local garage who tested the battery, and it was completely flat. I ran it home and replaced it. Checked the old battery with a multimeter and there was nothing in it whatsoever!

How can a battery go from working normally to completely goosed in 5 minutes? Replaced the battery and that one has done a further 7 years so far. Car has the original alternator and nothing else was touched. Strange!

[The Beast 233]

Had a MINI JCW from new, did not do many miles in the week and left it permanently on a CETEK charger in my garage. When it was 5 years old I started it one Saturday morning, started fine, drove 9 miles to McDonalds to get breakfast, ran fine, locked car up in the car park and went in to order. Came out later, nothing, everything was stone dead. No lights, horn, radio just nothing. Called Green Flag who diagnosed dead battery. Started with a jump start, drove to Mini who fitted a new battery. They advised they where only meant to last 3 to 4 years !

[Alan Drover]

My MGB GT battery has been kept on an Accumate battery minder for some time now while I have been sorting out the overheating interrupted by the pan(dem)ic and my hip replacement and the Optima Red Top is probably dead now. I will put it on a conventional charger to make sure but lack of use doesn't help.

[autorover1]

I have found modern  battery's do seem to drop off a cliff edge when they fail. Had it happen to my  Discovery 3 , fortunately failed one day before the warranty expired and it was replaced . Up to that point no issues to indicate imminent failure .

[Clifford Pope]

I think it happens when a corroded plate inside the battery suddenly breaks off. Modern batteries are smaller and of much less robust construction than formerly. Old batteries failed by getting sulphated up, but it happened very slowly and the battery just gradually lost its capacity. They would go on for years. Whether it mattered depended on how often you used the car. Daily use with a long run might be fine, a week's standing unused and it would be half flat - hence the starting handle.

Batteries used even to be serviceable. You could dig out the bitumin sealing round the top and pull out the plates, clean them up, flush out the muck from the casing and refill with fresh acid, and re-melt the bitumin again.

[diffwhine]

My wife's Discovery 2 did this a few years ago. Working happily towing a trailer and suddenly half way through the day it wouldn't restart. Hot day, warm engine - everything going for it, but the battery had just collapsed internally. Had to pay through the nose for a new battery on a Sunday from Halfords. I had the last laugh as that failed too, so I got my money back and bought a decent Bosch battery.

[2286]

I had a battery go pancake, and it was replaced with a brand new item that did the same.

It turned out to be a worn end bronze bush in the starter motor that allowed the armature to pull slightly diagonal and short, draining the battery.

Bush was spotted and replaced when starter was checked over.

OE battery always seem to be superior to replacements.

On the subject of batteries how do those optima yellow and red top items compare to regular on longevity?

Varta, exide, lucas used to be the go to brands for me as they are familiar from commercial applications.

[Alan Drover]

The Red Top Optima is an SLI (starter, lights, ignition) where the Yellow Top is a deep cycle battery and the former doesn't like going completely flat as I have found out with 2 Red Tops on my MGB. The battery on my Land Rover is an Odyssey which is both SLI and deep cycle. Expensive but you pays yer money and takes yer choice

[2286]

Optima usp was gel electrolyte and spiral wound plates?

Safer in comp use too?


On the subject of regular lead acid, I was trying to pinpoint why one from a booster pack issued smoke from the cell closest to the negative terminal.

It showed 12.31v when tested and has not been charged for a while.

I thought it had run dry hence the smoke, but output would be lower if that were the case?

Maybe low on electrolyte and plate distorting was the smoke cause.

I took off the caps and brimmed the level on each, non of which were dry or visibly distorted.

It was taking 1/2amp from the charger, and all cells gently gassing equally large bubbles that expanded then burst.

Not a small bubble rolling boil indicating a short.

An ideas about the smoke?

I realise its most like a bin job but was curious.

Is it possible for lead acids to have conflicting polarity within the cells?

[Alan Drover]

You're right about the Optima.
Maybe the booster pack was overcharging.

[Alan Drover]

The Optima Red Top on my MGB had been connected to a battery minder but the indicator light on the minder had been stuck on yellow for weeks ever since I spun the engine over to try to get oil pressure which the battery couldn't manage even with the head off.
I removed the battery and the voltage was 11.76. I tried it on my C Tek cordless charger and within the hour indicated on the machine that it would take to bring it up to charge the charger indicated that voltage had been reached. 25% of the  charger's internal battery had been used. I then measured the battery voltage which was 13.17. I've now transferred the battery to my ancient but very reliable Bradex battery charger which will keep the battery up to charge far better than a minder. The latter can't cope with batteries that are almost flat.
I suppose the best thing to do if the battery is on the vehicle is to jump start and leave the alternator to charge. If the battery doesn't hold the charge then it's scrap.
I'll disconnect the Optima from the charger in a couple of days and see if it holds the charge.
The Optima site says that most battery chargers can't recognise and charge a battery especially if the voltage drops to 10.75.

[Wittsend]

I had an Optima red top and it was still good after nearly 10 years - then I sold the vehicle.

The Ford battery in my car is 7½ years old and still going strong and that's with no maintenance changing between using the car.

I've had other cars where the battery was still good after 10 years 

All - have exceeded the "expected" or guaranteed life of the battery.
You should expect and get 3 years minimum, then you can get 5 yr guarantees for the better batteries.

The original topic starter has given no clue as to the age or make of the battery.

And yes, it's true a so-called smart charger is not so smart with a flat battery, i.e. one reading below 12 volts 

When the battery is reading in the 7 or 8 volt range or lower - it's toast (or as a Disney Duck).
An old fashioned battery charger might appear to revive a dead battery but you can be rest assured, now with winter on the horizon, the battery will let you down 


You could try tipping out all the old battery acid (makes good weed killer or brick cleaner) and re-fill with new acid. That's sulphuric acid at 33% concentration.
Another "trick" is to try "battery conditioning pills". These are EDTA salt which you put 1 pill per cell. You can buy EDTA (Google it) on eBay as a powder - you put 1 tea spoon in per cell and give the battery a shake. I've never had much success with this 
The battery soon gives up.