Battery failure

[RONNIECOROLLA]

I bought a new Battery on 31st May 2023 from a reputable manufacturer for my Toyota Corolla. In fact the same make of Battery that was fitted to the car when new which lasted over 10 years.

 My car was off the road with a brake problem so every week or two I started and ran it for 10-15 minutes (so approximately six occasions) then I disconnected the Battery, partly as a theft deterrent. This is a car that has reliably started first time, every time. All was fine for two months but at the beginning of August I had difficulty starting the car. I removed the battery to charge it and found it was only registering 6V? It refused to charge at 12V or various voltages from 6V to 12V or at various low amp settings. My car alternator was checked and read about 14V.

 The battery had a 4 years warranty but when I raised the matter the warranty firm responded with various battery jargon – deep cycling, over cycling, parasitic leak and sulphation. They said a drop in voltage is not covered by the warranty?

 I cannot believe a brand new fully charged battery starts a car on six occasions over a two months period then fails and is useless and beyond recovery. In the past I have left my car for three or four weeks and it has always reliably started.

 Can anyone offer a more credible explanation?

Regards.

[Saxmaniac]

Before condemning a faulty Battery it's an idea to be sure you haven't got a parasitic drain and that the alternator is working correctly. It's not ideal use for a Battery to just run the car for 15 minutes, (not good for the engine either but that's another matter). So the supplier may have a point, a local small Battery shop by me supplies, fits and checks the charging as part of the service at no extra charge so worth going to independent shops 

[TonyHSD]

Agreed with Geoff., 

these 10-15 min runs and lack of use most likely has killed the Battery. 
If me, I will buy new one, fully charge it before installing into the car and then if the car is not in use regularly I will either connect a solar charger to maintain charge or charge with smart charger one a month or so. 
If using the engine as top up minimum 30-40 min running time after start up otherwise it’s worse than not starting at all. 
 

[Roy124]

Agree, unlike a hybrid that just needs 12v to start, and ICE require hefty pull to start.  The alternator will then recharge it quite quickly.  The key is 'quite'.  Normally, having started the car, you will drive it and the alternator will do the bizz.  At idle RPM the output will be less.  Also, if you have lights on, radio playing,  conditioning then you can be in negative territory.