12v battery death

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The Wi-Fi module has been known to drain the battery. Please note that if the battery is drained 2-3 times, it's already dead mostly :)

Please make sure you have the correct type of battery placed.
 
It's most likely down to the fact that the battery is no longer able to hold it's charge. If a 12V lead acid battery falls below 10V for any length of time then permanent damage is done further reducing it's capacity. Even regeneration will probably not fix it in the long term.
 
My Outlander PHEV is 2018, I think it was built about July. It was a dealer demo in NZ and was 8months old when I bought it, with under 400km on the odometer.

Recently during regular servicing (October 2022) the 12volt battery was tested and was found to be Good. I don't know why they tested it, probably my stated concern about Drive battery SoH was lost in translation, whatever.

Last week after going to and from work, plus to and from super market, totalling less than 20km after a full charge, I went outside about 8pm to check I had locked the car although I had plugged in as I use timed charging from 9pm to midnight (because it's free). I could not lock the car, It was totally dead. 12 Volt battery was down to 2 volts. No doors were open so no interior lights on and it is set to shut off accessory circuit after 30 minutes. Headlights are always set to Auto. Even if I left it in Ready state the DC-DC converter should have maintained the 12 volt system.
Timed climate control was not on, I had used it a couple of times the week before to cool the car when I finished work but I had turned the timers off.
So I have no idea what caused the battery to run down. I tried using a battery charger, but being a "Smart" charger, it refused to start because the battery was too dead. Not so fxcjing smart after all really. The only way to recover was a Jump start with another battery. The car immediately powered up with lights on just as it does when unlocking it in the dark. And it started charging the 12v battery. I could see 14V at the jumpstart terminal in the fuse box. Also It was charging the drive battery as I probably cancelled the timer with remote fob. For some reason I went to check the battery itself but to my horror It was HOT and the grounding cable was also hot or at least Very Warm. That suggests a lot of current from the converter. I immediately shut down everything and removed the battery. I put it on a 25amp (other smart) charger but it's leads were getting too warm for comfort. (I will say those leads are actually inadequate for that current)

The whole episode freaked me out big time. I have no idea why it happened and no idea why the converter was so agressive. I had to run with the non fitting other battery for a day and get the original one tested, which again came out as good, with better CCA figure than it's stated rating.

I have rechecked/reset all settings and so far everything is normal.

Any one got any ideas on this?
Get a 12V LiFe PO4 battery for $200. I got mine(2018 PHEV) for a year without any problem at all.
 
Get a 12V LiFe PO4 battery for $200. I got mine(2018 PHEV) for a year without any problem at all.
Do you have any model number or link for reference? Mine is getting old and keeps dropping charge and I don’t want to get stuck next winter - I’m based in the UK if that makes any difference. Thanks!
 
Do you have any model number or link for reference? Mine is getting old and keeps dropping charge and I don’t want to get stuck next winter - I’m based in the UK if that makes any difference. Thanks!
https://www.aliexpress.us/item/3256...t_main.10.9df11802wtGC0S&gatewayAdapt=glo2usa

you would need the Negative L battery. Their life cycle should last 5 to 6 times those of lead acid batteries.

1712034075336.png
This battery has a built-in BMS chip inside to regulate charging and you just install it like your regular lead acid battery. You do need a special LIFePo4 battery charger if needed. I always charge my 12V batteries at least once a year at home. I got this charger for both lead & LiFePo4 batteries. I installed it since early January 2023, no problem so far. My detector shows over 13-14V at full charge.

https://www.aliexpress.us/item/2255...t_main.15.35db18020tcVfF&gatewayAdapt=glo2usa
1712034131810.png
 
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