Modern vehicle battery voltages too low for charging dashcam external batteries?

[dvttipspe]

With newer cars and their car battery management systems, voltages seem to range from 11.7-15V while the engine is on.
With all the external dashcam batteries needing at least 12V to charge, how many of you are encountering charging issues?

For myself, I have had to switch from fast to slow charging mode. With fast charging, there is too much of a voltage drop causing the charging voltage from the car battery to drop below 12V, thus not charging the dashcam battery. With slow charging, there is a lesser voltage drop and therefore charges more reliably.

Has anyone found solutions for this?

 

[Vortex Radar]

I sometimes see low voltage warnings on my batteries when my start/stop system engages at a red light and so the engine shuts off. Luckily the dashcams still stay in driving recording mode and I don't have any issues with it switching between driving and parking mode at red lights, even when the engine turns off for a bit. I’ve got 3 different batteries (plus some expansions) and no issues even with all of them set to high speed charging.

 

[marcomrctavares]

On my 22 Trx works perfect with 3 ext batteries, but I have the same issue on my Wife’s 22 Outlander. Let us know if you find any solution

 

[majones]

Good question. I hadn't thought much about this before investing in a dashcam, so I'm struggling to get parking made to work as I would wish. I don't use my car much and the lead acid battery voltage stabilises at about 12.3V (measured with BM2 bluetooth device), so on my short trips the alternator to battery voltage difference is enough to achieve stability and my car starts fine with 12.3V all year round. Setting my camera BAT voltage cutoff to 12.2V gives me about 2 hours of parking monitoring that isn't anything like enough, but I don't want to drop the cutoff voltage to 12.0V or 11.8V because I don't want to be stranded with a car that won't start. Obviously an additional LiFePO4 battery won't help as all it will do is to steal alternator charging power from the the lead acid battery on my short trips, plus it really needs >12.5V to charge meaningfully. So I suppose the question is whether people have 2 or more LiFePO4 batteries and swap them out after charging off the car?