Parking Battery-Power Station, 3X capacity and 3X cheaper than dedicated options + extra functionality

[GPak]

Update since I'm back from my trip. The 161Wh power station ran overnight for about 12 hours. In the morning, it had dropped one of the battery status bars (>60%, <80% remaining?). I kicked of the 322Wh power station while parked at the airport (~78 hours). When I got back the vehicle, the power station was off. When I turned it on though, it showed as completely full according to the display. When I checked at home, it had done the event recording (motion and impact) for exactly 12 hours. I'm pretty sure the Viofo was set to not have a timer, and I didn't think the power station had a timed shutdown. More experimenting needed.

I finally completed auto-shut-off tests on Necespow N150 and N300 Power stations.
Both will auto-shut-off after a little over 12 hours, regardless of load or no load.
Once PS turned ON due to ignition, the time will re-set to start over for another 12 hours after ignition is OFF.
So, if there is need to run parking mode continuously over 12 hours then check different Power Stations (EcoFlow or Baseus or etc.)
My parking duration is set to 10 hrs and it works.
I updated my Post #4 accordingly.

Here is response from seller/manufacturer:

 

[kawayanan]

I finally completed auto-shut-off tests on Necespow N150 and N300 Power stations.
Both will auto-shut-off after a little over 12 hours, regardless of load or no load.
Once PS turned ON due to ignition, the time will re-set to start over for another 12 hours after ignition is OFF.
So, if there is need to run parking mode continuously over 12 hours then check different Power Stations (EcoFlow or Baseus or etc.)
My parking duration is set to 10 hrs and it works.
I updated my Post #4 accordingly.

Here is response from seller/manufacturer:

Thanks for doing the test and checking with the manufacturer. I have run into the shutdown a time or two since the extended parking at the airport, but its pretty rare. I would say that 12 hours covers my usage 90% or more of the time. 12 hours is not bad, especially for the price and considering that the PS can be used as a power station too.

In the week+ I have been using the N300, I haven't had any times that the charge has dropped below the first status indicator. That is to say, when the vehicle is off and the power station is running (powering parking mode), its status always shows completely full. When the vehicle is running, it flashes the final indicator showing its charging. I take this to means that for my driving (20-40 min commute each way), it charges enough to cover the parking mode for the rest of the day (overnight, parked at work, etc.) without ever dropping below the 80% level. This is using only the USB-C PD charging input (I still haven't gotten the center DC input setup). Overall, the N300 seems to be more battery than I will generally use (with the 12 hour limit), and a single charging input keeps it happy. I may switch to the N150 and see how it does.

Since you mentioned the the ignition re-sets the 12 hour timer (seems true from what I have seen), I wonder how much charging input is needed to keep the timer from running down? Since I only seem to need the USB-C input to keep the PS charged, I could be free to use the center DC input for a small solar cell. If it got enough sun to supply some level of charging, that might reset the 12 hour timer. Either enough sun to top off the PS, or even just enough to keep it awake might be easy to do.

 

[GPak]

Since you mentioned the the ignition re-sets the 12 hour timer (seems true from what I have seen), I wonder how much charging input is needed to keep the timer from running down? Since I only seem to need the USB-C input to keep the PS charged, I could be free to use the center DC input for a small solar cell. If it got enough sun to supply some level of charging, that might reset the 12 hour timer. Either enough sun to top off the PS, or even just enough to keep it awake might be easy to do.

During charging at any rate PS will not shut down, in fact it is impossible to shut it down even manually pushing and holding power ON/OFF button when charging.
On Solar charging:
I actually tested two portable/fordable Solar panels rated at 60W.
Panels are small enough to fit my dashboard.
I will post those test results soon.

 

[GPak]

Tested two Solar panels Necespow and Baldr from Amazon, both rated at 60W, both around $60 when on sale.

My main driver to choose the Solar Panel was portability and size to fit my dashboard and also cost.
Baldr is slightly larger and heavier, and looking at efficiency, it is probably a true 60W panel, Necespow on another hand is light and more like 40W panel, not 60W.

Here what they look like:

 

[GPak]

Two thinks to note:
-The windshield cuts Solar panel power output by half !
-Panels are not producing power if there is no direct sunlight (in fact, I noticed that power station W indicator showing about 0-1W draw, not sure, but it looks like some kind of back flow?? it shouldn't be possible to draw power from power input port right?? All stations I used for test have MPPT chargers.

Here is the table with test conditions and results:

 

[forcefed]

Done and done
36 hours of parking mode @ 6 watts for $150 usd, powercell/cellink/blackvue take note.

 

[kamkar]

When someone can make something like that, with quite a few extra things in it, like a inverter ASO, well makers of dashcam power packs might soon loose customers / sales.

 

[GPak]

@forcefed , Thanks for testing this.
36hr x 6W = 216Wh usable! That is about 84% efficiency, excellent outpoot from USB port!
Picture is a little misleading, you need to put cellphone next to power station, so people can see how small it really is.

For people who needs even longer parking recording, expected parking time for 512Wh version “EcoFlow River 2 Max” would be 72 hrs, that is 3 full days! for 2ch dashcam.

@kamkar , Exactly,
EcoFlow is well established and is one of the best brands in Power Station market.
It is a little pricier compere to some no-brand Power Stations, like the one I am using, and yet they are able to produce such a feature-rich product at an affordable price.
2.3X usable capacity + extras, for 2.3X less money, from a reputable brand like EcoFlow, compered to dedicated battery.

I understand that the market for power stations is probably much larger than the market for dedicated batteries for DashCam, but so is the competition: there are literally tens, if not hundreds of power stations on the market.

 

[kawayanan]

Two thinks to note:
-The windshield cuts Solar panel power output by half !
-Panels are not producing power if there is no direct sunlight (in fact, I noticed that power station W indicator showing about 0-1W draw, not sure, but it looks like some kind of back flow?? it shouldn't be possible to draw power from power input port right?? All stations I used for test have MPPT chargers.

My vehicle is a Ford Maverick hybrid, and I have a tri-fold tonneau cover (hard bed cover). I have been thinking of putting a more permanent solar panel on the bed cover panel. That way it is not behind glass and lying flat.



Not sure how much it is worth for me though. The few times I would be parked for longer periods, it may be in a parking deck at the airport (no sun). Other than that, the power station has plenty of capacity, I just have the 12 hour cutoff on the Necespow. The tempting part would be to have the solar panel keep the PS awake, any charging would just be a bonus

On another note - I mentioned that just using the USB-C input seemed to be keeping the PS charged. That may not be true. Yesterday, the PS was showing full when I parked, but one hour later the PS was off and showed empty. This was after about two weeks of usage (parking mode for ~8hrs at work, ~12 hrs overnight; ~30-45min commute each way). I was wondering how accurate the meter was considering how flat the voltage profile is for LiFePO4 across the upper part of the capacity percentages. I'm assuming that it was running down over the two weeks but the gauge just wasn't accurate.

Interestingly, I have never seen the USB-C PD input pull more than 1 amp at 20V (assuming the USB power adaptor is accurate). It should theoretically be able to do 65W, but seems to be staying around 15W (0.7A @ 20V). I don't know why it isn't charging with more power.

This adds a little impetus to getting the dual charging setup going.

 

[GPak]

On another note - I mentioned that just using the USB-C input seemed to be keeping the PS charged. That may not be true. Yesterday, the PS was showing full when I parked, but one hour later the PS was off and showed empty. This was after about two weeks of usage (parking mode for ~8hrs at work, ~12 hrs overnight; ~30-45min commute each way). I was wondering how accurate the meter was considering how flat the voltage profile is for LiFePO4 across the upper part of the capacity percentages. I'm assuming that it was running down over the two weeks but the gauge just wasn't accurate.

I noticed that bar indicator is more or less accurate when drawing normal amount of power, but for DVR use, with trickle power draw it becomes not that accurate, and charging and drawing power at the same time does not help either.

About daily driving/parking schedule:
If you are driving 2 x 45min =1.5h, and charging at about 60W, then you are adding about 81Wh of energy in to PS per day (assuming PS charger efficiency at 90%).
2CH DVR in low bit-rate parking is drawing about 5.5W per hour (including self-consumption), so for 8+12=20h parking, you are using about 110Wh.
110-81=29Wh per day discharge.

N300 useful capacity is about 245Wh using USB port, hence 245/29=8.45 days or 8 days and 10h before you run out of juice.
If during that period you do some additional driving say for shopping than that time is farther extended

 

[GPak]

Interestingly, I have never seen the USB-C PD input pull more than 1 amp at 20V (assuming the USB power adaptor is accurate). It should theoretically be able to do 65W, but seems to be staying around 15W (0.7A @ 20V). I don't know why it isn't charging with more power.

This adds a little impetus to getting the dual charging setup going.

Now about not being able to charge at 60-65W rate with USB-C(PD).
This is not right and something is wrong.

Trouble shoot as follows:
- Disconnect DVR cable from PS then charge PS and check charge rate - if fixed, then DVR wiring is incorrect (usually, when ACC USB negative wire is not terminated but connected to negative wire of USB Power, then charge rate is negatively affected, ref. Post #8)
If not fixed
-Charge PS in different car using the same power adapter and USB-CPD cable – if fixed then something is wrong with your track cigar socket
If not fixed
-Check if your power adapter and USB-CPD cable is rated to at-list 60-65W (100W better) is so, still replace one by one cable and adapter to ensure they are not causing the issue.
If nothing worked then something is wrong with PS itself​

 

[kawayanan]

Now about not being able to charge at 60-65W rate with USB-C(PD).
This is not right and something is wrong.

Trouble shoot as follows:

• Disconnect DVR cable from PS then charge PS and check charge rate - if fixed, then DVR wiring is incorrect (usually, when ACC USB negative wire is not terminated but connected to negative wire of USB Power, then charge rate is negatively affected, ref. Post #8)

If not fixed

• Charge PS in different car using the same power adapter and USB-CPD cable – if fixed then something is wrong with your track cigar socket

If not fixed

• Check if your power adapter and USB-CPD cable is rated to at-list 60-65W (100W better) is so, still replace one by one cable and adapter to ensure they are not causing the issue.

If nothing worked then something is wrong with PS itself

Thanks for the reply - I am using the HK4 hardwire kit, but not in the way you did in post #8. I left it as is (12V) with the voltage regulator still in place. The HK4 lead are: ACC lead to a ACC fuse tap, the black to a vehicle chassis, and red (battery) to the PS 12V DC output (+). The PS 12V DC output negative is run to the vehicle chassis.

I'm not using a cigarette light adaptor, but instead have a 12V USB outlet (https://www.amazon.com/gp/B0C8N56TR7). This is wired to a fuse tap (+ side), and the negative to vehicle chassis. The outlet claims 65W via PD USB-C and another 18W via QC3.0. The PS is then charged through a USB-C/USB-C cable that was sold as a 100W charging cable. The cable is longer than I need (6.6ft), so I could try a shorter cable.

I'll test things when I get a chance.

 

[kamkar]

EcoFlow is well established

Indeed its not even some generic brand we are talking about, just make it even more suspicious.
Of course there is the size of the 2 markets, dashcams and power banks, but i think it is fair to say both are not the kind of stuff anyone would like one off like phones.
I can see the market for dashcam power packs taking off as smart cameras win more and more market share in the near future.

I am familiar with the price on batteries them self, as aside for dashcams i also nurture a minor flashlight addiction.

 

[forcefed]

@forcefed , Thanks for testing this.
36hr x 6W = 216Wh usable! That is about 84% efficiency, excellent outpoot from USB port!
Picture is a little misleading, you need to put cellphone next to power station, so people can see how small it really is.

 

[GPak]

Thanks for the reply - I am using the HK4 hardwire kit, but not in the way you did in post #8. I left it as is (12V) with the voltage regulator still in place. The HK4 lead are: ACC lead to a ACC fuse tap, the black to a vehicle chassis, and red (battery) to the PS 12V DC output (+). The PS 12V DC output negative is run to the vehicle chassis.

I'm not using a cigarette light adaptor, but instead have a 12V USB outlet (https://www.amazon.com/gp/B0C8N56TR7). This is wired to a fuse tap (+ side), and the negative to vehicle chassis. The outlet claims 65W via PD USB-C and another 18W via QC3.0. The PS is then charged through a USB-C/USB-C cable that was sold as a 100W charging cable. The cable is longer than I need (6.6ft), so I could try a shorter cable.

I'll test things when I get a chance.

12V system is not different than 5V system.
Your wiring is same as in Post #8 except you connected all negatives through chassis including ACC negative is not terminated but connected to negative DC port and HK4 Black wire, likely effecting charging rate.

Try to connect 12V DC negative directly to HK4 Black wire as shown on attachment, I believe this will fix your charging issue.

 

[forcefed]

12V system is not different than 5V system.
Your wiring is same as in Post #8 except you connected all negatives through chassis including ACC negative is not terminated but connected to negative DC port and HK4 Black wire, likely effecting charging rate.

Try to connect 12V DC negative directly to HK4 Black wire as shown on attachment, I believe this will fix your charging issue.

Somewhat similar issue i was having before with the usb>acc wire in post #116 and #120, the gnd should be connected to the gnd of the 12v source and not the chassis.

 

[kawayanan]

12V system is not different than 5V system.
Your wiring is same as in Post #8 except you connected all negatives through chassis including ACC negative is not terminated but connected to negative DC port and HK4 Black wire, likely effecting charging rate.

Try to connect 12V DC negative directly to HK4 Black wire as shown on attachment, I believe this will fix your charging issue.

When differentiating between 12V and 5V, I just meant that I kept the HK4 intact as opposed to clipping off its 12V to 5V regulator.

For clarity on how I had it wired, I had used one chassis point for for the USB adapter and the PS DC output negative, and a separate chassis point for the HK4 black/ground. My wiring looks like this:



It seemed to me like this should have work, since even if I disconnect the dashcam from the PS DC outlet (so just PS charging, no dashcam in the equation), I still get the same ~0.7A@20V current indicated on the USB adapter (again, assuming it is correct). You were right though. It worked and bumped up to 2.55A@20V (51W) when I changed the wiring to this:



Thanks again for your help. I'll post my plan for the dual charging (USB-C PD and DC input) before I do it to get expert advice

 

[kawayanan]

Okay, hopefully my repeated posting doesn't bother anyone. My Maverick hybrid has the battery under the back seat, so its accessible inside the vehicle. This way I could potentially do dual charging (USB-C PD and direct 12V DC) by going to the vehicle battery with a SPDT relay (like this or this). I figured I would go with a SPDT (5 pin) over the SPST (4 pin) in case I ever wanted to add a solar panel. The relay would be activated off of the ACC fuse tap. The normally open to the battery so that charging off the battery would only occur while the vehicle is running, and the normally closed could be potentially used for a solar panel (closed when the vehicle was not running). Not sure about what should be connected to chassis/ground vs to the battery negative. I assume that splitting both the direct 12V DC and the USB adapter off the same line to battery/relay would be okay?



Are there any major issues with my idea? Thoughts?

 

[GPak]

Are there any major issues with my idea? Thoughts?

First of all, I'm an engineer, but not electrical engineer, so take my advice with a grain of salt.

I am not sure about Hybrid cars, but generally Chassis and Battery negative is the same (connected), although I prefer to pick direct negative instead of going through chassis (that could be the reason why you are getting 51W charge rate instead of 60-65W).

Using Relay connected to Battery/Alternator instead of ACC tap could be beneficial, especially when high current draw is required, but not for solar as depicted.
Keep in mind that open circuit solar voltage is not constant and can be up to 25V max allowed by N-300 (check the manual) and I think it is better to keep it isolated from car electrical system, meaning do not ground it to car negative/chassis or connect to car electrical system directly any other way.
Also, per your diagram the Soar Panel is going to power both USB-CPD and DC charging port and I do not think that is a good idea either.
I do not know exact internals of N-300 charging circuit, but I believe DC charging port is only MPPT, dedicated for soar input, hence the Relay for Solar input should be on DC charging line, and if you stick with ACC tap that would be your only relay.

Of course, you can always test, to check if it works.

 

[kawayanan]

First of all, I'm an engineer, but not electrical engineer, so take my advice with a grain of salt.

I am not sure about Hybrid cars, but generally Chassis and Battery negative is the same (connected), although I prefer to pick direct negative instead of going through chassis (that could be the reason why you are getting 51W charge rate instead of 60-65W).

Using Relay connected to Battery/Alternator instead of ACC tap could be beneficial, especially when high current draw is required, but not for solar as depicted.
Keep in mind that open circuit solar voltage is not constant and can be up to 25V max allowed by N-300 (check the manual) and I think it is better to keep it isolated from car electrical system, meaning do not ground it to car negative/chassis or connect to car electrical system directly any other way.
Also, per your diagram the Soar Panel is going to power both USB-CPD and DC charging port and I do not think that is a good idea either.
I do not know exact internals of N-300 charging circuit, but I believe DC charging port is only MPPT, dedicated for soar input, hence the Relay for Solar input should be on DC charging line, and if you stick with ACC tap that would be your only relay.

Of course, you can always test, to check if it works.

I'm not any kind of engineer My education is biochemistry and biophysics, and anything even remotely close to electrical is simply from either hobbies or learning things to be a general handyman.

You make some very good points there, that I should have caught. I hadn't really thought through the solar yet as it was a "future" kind of idea. You are very right though, it definitely needs to go through the DC input due to is varying voltage. The USB-C side of things is expecting 12V. I could use a DPDT relay, and have the two output sides (USB and DC input) kept completely separate. It probably makes more sense to simply wire without the solar first, then is just needs a simple SPST relay. I could ad in a separate setup for the solar if I ever actually go down that route.