Using a AGM Deep Cycle Battery/LiFePo4 battery for dashcam

*Sorry removed my earlier post. I was too impatient lol. Should have completed my maths properly.*
Reposting.
Another question for you guys. I've just found out (no I did not know this before - not an electrical engineer or anything haha). So most powerbank's capacity is at 3.7V (because of the way of lithium cells yeah).

So for a 5V output, there is naturally loss and the rough estimate is around 5V = 3.7V*mAh/5V. So if we consider a 10,000mAh Power bank, charging a phone, it's more around (not exactly) 7400mAh+heat loss/etc for 5V draw.

Also I assume, if we pull 9V (for example fast charging) OR 12V for a camera hard-wire into power bank for example, that would mean I have further mAh loss? Correct?

So looking at the Cellink/Blackvue Battery packs or others, they mention this;
1631103688593.png
So that 6,000mAh they say, I am sure they mean it at 12.8V itself thus the 76.8Wh rating (6000mAh/1000=6Ah*12.8V = 76.8Wh).

So if I was to use a 3.7V 40,000mAh powerbank and pull out 12.8V from it, that means I end up with a capacity of 11,562mAh@12.8V (11,562mAh = 3.7V*40,000mAh/12.8V) + normal heat/conversion loss whatever. Assuming lossless conversion, that still equates to 11.5625Ah*12.8V=148Wh.

So even though that Cellink/Blackvue battery is 6000mAh@12.8V, and this powerbank is 40,000mAh @ 3.7V, this powerbank is only roughly 2X larger correct and will power the camera at 12V for roughly 2X longer? (76.8Wh vs 148Wh). Is my math and understanding correct?

Also: How much wattage (also voltage and amps) do dashcams normally use in 2CH? I know it differs but roughly. Is it actually 5V or do dashcams actually operate at 12V? Do hardwires step down voltage (thus some power loss). What exactly does a hard-wire kit do? What's that little box in Viofo kits fot example with voltage settings actually doing? Is it downstepping 12V to 5V. Correct? Thus some power loss?


Cheersio!
 
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So even though that Cellink/Blackvue battery is 6000mAh@12.8V, and this powerbank is 40,000mAh @ 3.7V, this powerbank is only roughly 2X larger correct and will power the camera at 12V for roughly 2X longer? (76.8Wh vs 148Wh). Is my math and understanding correct?
That is correct.
It gets confusing unless you do the comparisons in Wh, then it is simple.
You do need to be careful about claims of 40,000mAh on USB powerbanks, USB powerbanks that size are rare but there are many fakes!
 
That is correct.
It gets confusing unless you do the comparisons in Wh, then it is simple.
You do need to be careful about claims of 40,000mAh on USB powerbanks, USB powerbanks that size are rare but there are many fakes!
Yeah I've learnt that haha. The 40,000mAh I use in my trash dashcam (has no parking mode, it's for an old car, will probably stop doing this once I find a solution for my other cars too), is a Romoss 40,000mah powerbank. The reviews seem legitmate and its quite heavy so I have faith this one is indeed real. But yeah I've seen 1,000,000mah power banks on ebay for like 20 bucks weighing 500 grams XD.

Also (to anyone that knows): How much wattage (also voltage and amps) do dashcams normally use in 2CH? I know it differs but roughly. Is it actually 5V or do dashcams actually operate at 12V? Do hardwires step down voltage (thus some power loss). What exactly does a hard-wire kit do? What's that little box in Viofo kits fot example with voltage settings actually doing? Is it downstepping 12V to 5V. Correct? Thus some power loss?
 
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Also I temporarily cancelled the Power Station I ordered off AliExpress (it was not shipped so I will get my money back);
This is the product:

I have asked and confirmed with the seller and they claim it is a LiFePO4 battery (because in the description it did say "Battery type: Lithium Iron" - but that 'iron' could easily be 'ion' right, and be misspelled. So I double checked, they do claim it is indeed Lifepo4). However, the only reason I cancelled it was because; this 1 review said the capacity is fake. And of course I have seen fake powerbanks on ebay aliexpress for like 20-40 bucks, but, for 240, is this fake or not?

What do you guys think? (I would be happier to buy a more reputated power station like an energizer, but in Australia I barely can find any of these). Is this worth a risk/buy? Worst case, I will replace the batteries in 1-2 years myself, but is it worth the initial try? Lemme know your opinion.
 
Also (to anyone that knows): How much wattage (also voltage and amps) do dashcams normally use in 2CH? I know it differs but roughly. Is it actually 5V or do dashcams actually operate at 12V? Do hardwires step down voltage (thus some power loss).
An FHD 2ch takes about 2.5 watts, 2K about 3.5 watts and 4K or 2K 3ch about 5 watts, measured at 12 volts before the HWK thus including any losses. From a 5 volt power bank will be the same because that has the same losses from the 3.7 to 5 volt conversion.
 
An FHD 2ch takes about 2.5 watts, 2K about 3.5 watts and 4K or 2K 3ch about 5 watts, measured at 12 volts before the HWK thus including any losses. From a 5 volt power bank will be the same because that has the same losses from the 3.7 to 5 volt conversion.
Appreciated. :)
 
What exactly does a hard-wire kit do? What's that little box in Viofo kits fot example with voltage settings actually doing? Is it downstepping 12V to 5V. Correct? Thus some power loss?
It converts the voltage to about 5.2 volts from whatever the vehicle provides, maybe 24 volts from a truck, provides a low voltage cut off when the battery drops to the selected voltage such as 11.8 volts, and sends a "parked" signal to the camera so that the camera knows when to enter parking mode/shut down/start up depending on camera settings. Also provides the power cable to connect the camera to power without having to occupy an accessory socket and have wires trailing across the dashboard.
 
It converts the voltage to about 5.2 volts from whatever the vehicle provides, maybe 24 volts from a truck, provides a low voltage cut off when the battery drops to the selected voltage such as 11.8 volts, and sends a "parked" signal to the camera so that the camera knows when to enter parking mode/shut down/start up depending on camera settings. Also provides the power cable to connect the camera to power without having to occupy an accessory socket and have wires trailing across the dashboard.
Awesome awesome. Thank you.
 
Just to give you an idea of dashcam run times, I charged my Cellink B (6Ah) + 18Ah external battery and then run my A139 + Rear Camera in low bitrate parking mode. I ended up getting roughly 65 hours runtime from it.

So that's 24Ah x 12.8v = 307Wh

307Wh / 65 = 4.7Watts

This seems about right, remember there are probably some losses in the conversion 12v to 5v and also the capacities might not be quite what is stated.

If you use motion detect you might prolong that even more.

Interestly the charge time (just recharged this morning) was spot on. It took just over 5 hours at 5Amps
 
Just to give you an idea of dashcam run times, I charged my Cellink B (6Ah) + 18Ah external battery and then run my A139 + Rear Camera in low bitrate parking mode. I ended up getting roughly 65 hours runtime from it.

So that's 24Ah x 12.8v = 307Wh

307Wh / 65 = 4.7Watts

This seems about right, remember there are probably some losses in the conversion 12v to 5v and also the capacities might not be quite what is stated.

If you use motion detect you might prolong that even more.

Interestly the charge time (just recharged this morning) was spot on. It took just over 5 hours at 5Amps
Sounds brilliant.
Yeah I use motion recording. Honestly anything over 1 day is minimum for me. Anything over 3 days is great. Anything around a week would have been god-like hahaha.
 
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