Hybrid connection Car Battery->Powerbank->DashCam

[TheBo]

Hi Guys,
viofo a139 3CH owner here.
I have a 2022 Civic with its 45Ah battery.
I have a Viofo HK3-C hardwire kit.
usually in spring i got almost 8h battery uptime only from car battery.
I was looking at powerbanks (Power Core 6200LFP-PLUS, cellink neo 8, Blackbox powercell 8) but soon realised that since the power drain of A139 3CH is so high i will get the same amount of uptime from any 7500 mAh powerbank.
So i was wondering if there was any way to have an hybrid connection between powerbank, car battery , and hardwire kit. I mean using the powerbank to power the dashcam, once it is depleted the power is feed via car battery prolonging the dashcam activity. Tha car battery should be protected by the same logic LVP that is used in hardwire kit, still this has to be implemented on the input side of the lifepo4 powerbank since otherwise it surely cannot be feed by 10/15Amp current for fast charge when car alternator is in use.

Any suggest/ideas that are not just spending 700 euros in daisy-chaining powerbank's modules?

Let's brainstorm togheter hopefully something good comes out...

 

[Kremmen]

There is already a sizeable thread on this somewhere here.

The outcome was that only pass-through power banks would work properly and now that RavPower have stopped making them, presumably due to technical issues, it was considered unwise.

Someone here may be operating this successfully though.

 

[TheBo]

There is already a sizeable thread on this somewhere here.

The outcome was that only pass-through power banks would work properly and now that RavPower have stopped making them, presumably due to technical issues, it was considered unwise.

Someone here may be operating this successfully though.

First of all Thank you for taking the time to reply, much appreciated

i did scrap through the forum few hours tbh, and the most argument-near i did find was this https://dashcamtalk.com/forum/threads/my-solution-for-parking-mode-power-for-48-hours.39569/
still not comparable to the point of not asking if in the meantime commercial solution had risen to solve this.

 

[SPL15]

A 7500mah portable powerbank is not the same as a Dashcam battery's 7500mah. You need to compare watt hours for apples to apples comparison.

PowerCell 8 has an advertised 96 watt hours of energy.
A 7500mah portable power bank has 27 watt hours of energy.
Your 45AH car battery has a "theoretical" 540 watt hours of energy; however, in practical reality you'd only be able to extract maybe around 100 - 150 watt hours, using very optimistic estimates & a very low cut-off voltage, while also severely reducing its life expectancy to a few years at best.

There is no good way to "daisy chain" a portable power bank for what you're wanting to do. It's not very much power for runtimes, they charge super slow from a USB-A car charger, there's no 3rd terminal for competent parking mode, and Li-Ion isn't a very safe option for extreme ambient temps. There's no commercially available solution for doing this easily because it's not a very good idea to do...

There are much cheaper DIY ways to power a Dashcam w/ a DC-DC converter & LiFePO4 batteries; however, they are well outside the scope of what I'd recommend people do if they have to ask how to do it.

I agree that Dashcam batteries are WAY overpriced for what they actually are; however, they do offer a "mostly" plug & play solution that is safe & have a good warranty.
If you install it properly, you should expect 5 - 10 years of useful life out of it, which makes the ridiculous cost a bit easier to swallow.

 

[Kremmen]

Fully agree

From reading posts here and from experience of other battery devices, my theory is that many devices sit on shop shelves for far too long.

This results in the internal rechargeable battery becoming 'fully' depleted and when that happens they won't hold any charge for very long.

I bought a good make wrist fitness tracker with a published life of up to 10 days. It arrived totally dead and even after 24hrs on charge it still ran out within 24hrs. Reading online I was not alone.

I have 2 Viofo A119V3 and 2 Garmin Nuvi and because I don't do many miles I have a USB lead on my PC and I rotate the devices so each gets a boost charge every 4 days when not used in the car.

 

[TheBo]

A 7500mah portable powerbank is not the same as a Dashcam battery's 7500mah. You need to compare watt hours for apples to apples comparison.

PowerCell 8 has an advertised 96 watt hours of energy.
A 7500mah portable power bank has 27 watt hours of energy.
Your 45AH car battery has a "theoretical" 540 watt hours of energy; however, in practical reality you'd only be able to extract maybe around 100 - 150 watt hours, using very optimistic estimates & a very low cut-off voltage, while also severely reducing its life expectancy to a few years at best.

There is no good way to "daisy chain" a portable power bank for what you're wanting to do. It's not very much power for runtimes, they charge super slow from a USB-A car charger, there's no 3rd terminal for competent parking mode, and Li-Ion isn't a very safe option for extreme ambient temps. There's no commercially available solution for doing this easily because it's not a very good idea to do...

There are much cheaper DIY ways to power a Dashcam w/ a DC-DC converter & LiFePO4 batteries; however, they are well outside the scope of what I'd recommend people do if they have to ask how to do it.

I agree that Dashcam batteries are WAY overpriced for what they actually are; however, they do offer a "mostly" plug & play solution that is safe & have a good warranty.
If you install it properly, you should expect 5 - 10 years of useful life out of it, which makes the ridiculous cost a bit easier to swallow.

thank you for taking the time to reply!

in my OP i was only and just referring to LiFePo4 CAR 12V powerbanks. Since i writtend down in bold the specific names of the LiFePO4 devices i was referring to, I did not care to re-write LiFePO4 Powerbank each and every time, also the 7500 mAh reference were the cellink neo 8, Blackbox powercell 8 in my list, not being absolutely clear was entirely for my fault, sorry about that.
Before graduating at university (but in computer science and Programming) i did a mathematics and electronics high school, so i still have a home lab with few RIGOL's oscilloscopes, some soldering/reflowing stations, few bench/portable DMMS (brymen, Fluke, etc...) and other stuff. I do also test batteries from time to time with inrush current test, and discharge tests with DC LOAD (maynuo M9710), from time to time i do repair UPSes. So I am a bit fond of batteries ...lol... heck i also did a project with 3 rows of AMPERICS supercaps shipped for US to Italy just for a Jumpstarter project with LiFePO4 support battery and a boost converter to recharger from a semi-dead car battery.

Anyway back on topic, since i'm getting old (electronics are not my full time job and i do something else in my life), and work and family are sucking all my time (and will) i was hoping of something commercial not uber expensive and super reliable because of years and years of being used and tested by this community.