Random battery discharge

[anchorless]

Hi, new to the forum but have been lurking a while

Had my K11 1.0 (P reg) about 6 months, and at what seems to be completely random intervals the battery completely discharges (no clock/lights/turnover/anything).

This has happened probably 4 or 5 times in the last 6 months, and doesnt seem to be linked to anything at all. I even left it stood for a month at one point and it started first time, so this to me discounts battery issues.

I've been using it all week without problems but this morning it was completly dead. Tried to bump start, but just got a weird clicking noise from down by the fusebox. Once its connected to another cars battery and started it works just fine then, and can then work fine for weeks and weeks without issue

I have no extra electrical equipment installed, and as I say, this is completly random so dont know whats causing or how to fix

any ideas?? This looks to me like possibly an expensive fix and its just not worth it for a cheap car

 

[porkpie700]

I believe that the battery is defective; there may be damage to one or more of the cells/plates. Lead-acid batteries have a typical discharge rate of 10% per week of non-use, this rate increases when it reaches 40% of the total capacity because the sulphuric acid/electrolyte solution is stabilized by the presence of the stored electricity. Without electrical power the solution decays until it can no longer hold electrical charge.

You can get it tested if you wish, but I would just replace it with new, most new batteries come with guarantees as standard these days.
The k11 is best suited to a battery of at least 275AH total capacity with a delivery rate of at least 45AH. The clicking noise you heard is a symptom of the starter motor not having enough electrical power to turn over.