Discovered this afternoon to my horror that my battery was showing only 7.5 V. It worked perfectly fine before and the car was last used at 8:30 PM last night. Now seems like my daughter was playing with the front cabin lights and may have left them on. I don’t know the power rating of them, but I’m surprised it drained the battery completely. I check voltage before starting every time as my USB charger displays it, and it’s always been above 12.6 so I assume the battery was at least 75pct charged.
Nevertheless, this battery is nearing 5 years old, and I don’t know it’s history since I’ve only had the car 4 months . so I came back to this link that I’d seen before and did the right thing by ordering the Yuasa 5054 at £45.87 ( Thanks Cuzlean) a small price for the next 5 years peace of mind.
I know my old battery still has some life in it, will find some use for it powering something in the garden with a 12V solar maintainer Have removed and kept it to charge now.