Auxiliary battery

[Electronic man]

Hello all

 

I have a 2018 rcf 300H. Problem started after I returned from a 3 week holiday. ' hybrid system stopped put in P' sign came up. I put it on charger and the Battery was showing around 8 v. Quickly charged it up and drove 300miles without any issues. But the problem began to appear repeatedly with the charger showing 8-10 v. I ended up replacing the aux Battery. I didn't throw away the old Panasonic. I charged it up 4 weeks ago and left it in the garage. Just checked it today...still showing 12.2v. I wonder whether the problem was not with the Battery...or is it because it has no demand placed upon it?

[Littorio]

It could be a cell is down so it charges up to 12V but when there's a load put on it it can't hold 12V.

[ColinBarber]

Seems to have lost its capacity under load. Quite common once a Battery has been deeply discharged. I certainly wouldn’t want to rely on it. Best to take it to your local metal exchange and get a few quid for its scrap value. 

[Electronic man]

Thank you both. It puts my mind at rest..that I didn't spend £194 for nothing