My apologies for being AWOL- the hot humid workdays doing rough work aren't easy on an old man like me
and summer is only halfway over here
Of all of us here, I think
@Dashmellow has more experience with powerbanks than anyone else and that's probably your best bet: easy, safe, and relatively foolproof to do.
I think
@Nigel may be speaking in terms of an AGM
car battery swap, which would have advantages if you were doing nothing else, but my concept is more akin to an RV battery system, where the starting battery runs only the car same as now and an
added AGM battery runs the cams. The advantage is hands-off usage like the Neo, and as much runtime as you want which would be based on what size battery(s) you use. I mentioned this alternative because for the same price as a Cellink Neo you can get all the parts to do this and get 3-4 times the cam-time as you can get from a Neo (cost of your DIY labor not being considered) and unlike the Neo+B124 there's no limit on how high you can go(within reason). DIY intensive is the downside.
Probably moot since James seems to like the powerbank concept and it should serve him well.
@jokiin has 'his finger on the pulse' of dashcams and related issues better than anyone else I know, which him being a manufacturer dealing with customer service issues and warranties would make sense. If he says something, believe it.
Might be worth mentioning that
all batteries have temperature limits, and powerbanks should not be charged in below-freezing temps or in extreme heats. The numbers vary a bit based on the type of cells used in the powerbank. AGM battery technology has less extreme restrictions, which can be a factor when doing in-car charging.
Not a factor when charging powerbanks or other batteries in-home.
With some of our best folks helping out here now, I'll step back and watch- they are more qualified than me in the matters being discussed now
If you have questions on a RV-type AGM system I'll pop back in.
Phil