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Power bank to charge RC Pro and Air 2S batteries

Pondhopper

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Firstly, forgive me. There's a lot of threads on here about this subject but many of them are old and have expired hidden links.

I am looking to charge my Air 2S batteries and my RC Pro while out in the field, and wondered if this item would be sufficient please? I would like to get as many charges out of it for my batteries and RC Pro as I can and don't want to spend more than $100.

Portable Laptop Charger with AC Outlet, 97Wh/100W Laptop Power Bank 27000mAh External Travel Battery Pack with LED Flashlight for Tablet,MacBook Pro, Notebooks, Smartphone


Or maybe this one:


Or if you know a better one for $100. please let me know. It does not need a flashlight on it.
 
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This just turned up on email. Similar to the jackery ones but smaller size. You'd have to check stats but it says enough power to charge drones
I know this is an older thread - but wondering if anyone has tried this Anker 521 unit yet specifically for the RC Pro or Mavic 3 batteries in the field? Looks like a nice portable solution as its smaller than that Jackery one.
 
Nice form factor, but the actual specs of the ports seems to be lacking. Depending on the wattage output of the USB-C ports, it may take a very long time to charge a Air 2s battery or even the RC Pro. To charge in a reasonable amount of time, you need 65 watt output on the USB-C port, 100W is best. I have just gotten this charge adaptor for my vehicle, specifically to charge batteries for the drone. I have a larger power bank, a Bluetti, but the USB ports are a bit lacking in high output. I can actually plug this adaptor into the 12V output for a better charge rate.

Car charger
 
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Nice form factor, but the actual specs of the ports seems to be lacking. Depending on the wattage output of the USB-C ports, it may take a very long time to charge a Air 2s battery or even the RC Pro. To charge in a reasonable amount of time, you need 65 watt output on the USB-C port, 100W is best. I have just gotten this charge adaptor for my vehicle, specifically to charge batteries for the drone. I have a larger power bank, a Bluetti, but the USB ports are a bit lacking in high output. I can actually plug this adaptor into the 12V output for a better charge rate.

Car charger
The more I read on it, realized what you say- not quite enough output. And I was thinking the 12v regular ac plugs would be most useful.
I’ll take a look at that Blueti. I’m not in a rush to get one just yet. I haven’t been shooting so much lately that has become a problem. I have four Mavic 3 batteries, and that usually covers me pretty well for either a morning or in the afternoon session.
But I can certainly envision a longer day of shooting or a job where I would need a couple more batteries or to recharge the RC pro in the middle.
Which Blueti power pack do you have? The $299 or $399 ones are within reason. But I could also buy 2 more batteries…
 
Actually I have this one, it was a gift. I did an aviation consult for an acquaintance and he got this for me.
Bluetti

It is a bit on the medium size. These things all sound good in the write up, but in actual practice they are sometimes lacking. Like the inverter is a bit small. Too small to make my espresso machine work this winter when we lost power. That was a tragedy. I had to power up the gas generator or face a day without coffee. I use it to charge other small items and run the light sources on my field microscopes. I keep it topped up with a pair of solar panels.

There is really no good solution to charge stuff on the consumer side. I have in the past just made my own. I get an Oddessy 1200 battery and put it in an ammo box and put some 12v sockets on it. I just bought this unit to upgrade the one in this box, as it is an honest 65w (tested it with an amp meter). They keep getting better. My vehicle, a Land Rover Defender 90, has 4 USB-C charging ports, all are anemic. Besides new cars have so much electronics that sucking any juice out of the battery without the car running may keep it from starting. The Defender, while very cool, is nothing like my previous Defenders. Every time you open the door, it sucks down 10 amps to power up all the computers. Literally, when I am in the field, I put two small solar panels behind the windshield sun shade to keep the car's battery topped up. Heck my older Land Rovers even came with a hand crank to start the engine. I would need a small APU now.
plug.jpg
The sound system is actually a bluetooth card I got off Amazon or eBay, I forget which one, some car speakers. It actually sounds quite good. Now if my taste in music was better... but where I go there is nobody to complain.

box.jpg
 
I'd love to see a diagram & parts list for how you made this...
Not an electrician, but I can follow good instructions.
You say its a true 65w Is that a steady pure sine wave? And that is similar power to the Mavic 3 battery charge right? Ho do you recharge that Odyssey 1200 & how long does it take?

I'm not looking to power my fridge or cook while camping. Just want a reasonable way to charge my RC Pro & a few extra batteries for a long day shooting....

And as I read the Amazon user reviews I do see that its a bit of a crap shoot with all of those portable power banks. And not QUITE enough juice....
 
Ok, first, not to be condescending, let's clear up some terms. Pure Sine Wave. That refers to AC power, like from your wall socket. What our batteries consume is DC, hopefully no waves at all. The USB-C ports put out several different voltages, depending on what is receiving the power can handle. Anywhere from 20V to 5V DC. The Pure Sine Wave thing most of these power banks talk about is in reference to the inverter, which converts DC to AC for appliances and power supplies, things you would plug into the wall socket.

So essentially what you want is akin to a box with a small car battery in it. In this box, you put some sockets, much like you car has for 12V out. Additionally, in recent years, we can add things that do the various USB charging functions for our phones and drones. All the other stuff they talk about is noise.

Now since I first made that ammo box contraption, things have changed. I have gone through a couple of different batteries. It seems leaving it in my. hanger in the winter, which has the balmy temps of -20F during the winter is toxic for batteries. Battery tech is moving on, so I might be inclined to use a LI-FE battery now, probably will when the present one croaks. They are lighter for the same power density. More Amp hours per pound and size.

The adaptors, one is a straight 12v socket and the other a USB A & C outlet. They need a 1" hole drilled. The amp, which was similar to this one, but the one I have is long obsolete.
AMP

The USB socket is this one:
USB Socket
It is what you need to charge up the batteries, or you can plug something like I pointed out earlier into the regular 12V socket.

The speakers were what was on sale at the time at Crutchfield happen to be JBL's.

This is the battery I got the last time, since the Oddessey died:
Battery

The Ammo box is a .50 Cal size, but this one is for 10 Clips of 5.56. I kind of have a few left over from previous life. When everything is installed I stuff some closed cell foam bits in there to keep stuff from rattling. Surprisingly, it makes the speakers sound better.

The Switch was from, of all things dead and gone, Radio Shack. I like it since it lights up and keeps me from leaving it powered up most of the time.

Now I also have a Goal Zero Sherpa, a 25,600 mAh brick I use in the field when I go overseas. It will do 100W USB-C. Mainly I charge my phone and stuff with it, but it will do a battery for a drone fairly quickly, not too many of them though. It will fit in your backpack, even has a wireless iPhone charger. It is also hideously expensive. I got it on sale at REI with a 20% off coupon and some credit I had for something or other. I most likely would not have paid full price for it. However after having it in the field two seasons in South Africa and Namibia, I have become quite fond of it as has everybody in my camp.

box1.jpgbox2.jpgbox3.jpg
sherpa.jpg
 

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Ok, first, not to be condescending, let's clear up some terms. Pure Sine Wave. That refers to AC power, like from your wall socket. What our batteries consume is DC, hopefully no waves at all. The USB-C ports put out several different voltages, depending on what is receiving the power can handle. Anywhere from 20V to 5V DC. The Pure Sine Wave thing most of these power banks talk about is in reference to the inverter, which converts DC to AC for appliances and power supplies, things you would plug into the wall socket.

So essentially what you want is akin to a box with a small car battery in it. In this box, you put some sockets, much like you car has for 12V out. Additionally, in recent years, we can add things that do the various USB charging functions for our phones and drones. All the other stuff they talk about is noise.

Now since I first made that ammo box contraption, things have changed. I have gone through a couple of different batteries. It seems leaving it in my. hanger in the winter, which has the balmy temps of -20F during the winter is toxic for batteries. Battery tech is moving on, so I might be inclined to use a LI-FE battery now, probably will when the present one croaks. They are lighter for the same power density. More Amp hours per pound and size.

The adaptors, one is a straight 12v socket and the other a USB A & C outlet. They need a 1" hole drilled. The amp, which was similar to this one, but the one I have is long obsolete.
AMP

The USB socket is this one:
USB Socket
It is what you need to charge up the batteries, or you can plug something like I pointed out earlier into the regular 12V socket.

The speakers were what was on sale at the time at Crutchfield happen to be JBL's.

This is the battery I got the last time, since the Oddessey died:
Battery

The Ammo box is a .50 Cal size, but this one is for 10 Clips of 5.56. I kind of have a few left over from previous life. When everything is installed I stuff some closed cell foam bits in there to keep stuff from rattling. Surprisingly, it makes the speakers sound better.

The Switch was from, of all things dead and gone, Radio Shack. I like it since it lights up and keeps me from leaving it powered up most of the time.

Now I also have a Goal Zero Sherpa, a 25,600 mAh brick I use in the field when I go overseas. It will do 100W USB-C. Mainly I charge my phone and stuff with it, but it will do a battery for a drone fairly quickly, not too many of them though. It will fit in your backpack, even has a wireless iPhone charger. It is also hideously expensive. I got it on sale at REI with a 20% off coupon and some credit I had for something or other. I most likely would not have paid full price for it. However after having it in the field two seasons in South Africa and Namibia, I have become quite fond of it as has everybody in my camp.

View attachment 165305View attachment 165306View attachment 165307
View attachment 165309
Excellent. Thanks for the battery lesson too. I like to know the proper terminology.
And I could simplify it as I don't need the speakers.
Ammo boxes are very handy items, no?.... I've got a few.

Which Li-Fe battery would you use now?
Than link you show for the USB socket leads to a

Digital Stereo Amplifier Board, ZK‑MT21 Bluetooth 2.1 Channel DC 12‑24V, HiFi DIY Audio Power Amp Module, for 15‑100W 4‑8Ω Speakers"​

Doesn't look right - or is that the circuit board inside the box that wires up the speakers?
And I don't see how you Recharge the power bank.

thanks again for the info, sorry for my newbie questions...
 
Sorry, Fixed that link to the USB charger socket. If you don't want the stereo output, then the amp and speakers are indeed redundant. You just need the battery of your choosing, dimensions would be your guide along with price. As for the LiFe batteries. I only briefly looked into them. I would have to also get a charging system for that kind of battery. This one I have is healthy so it will be a bit before I get a new one and by then we may have portable fusion reactors. SO to charge this, two ways, one; pop the top and put a battery charger or trickle charger hooked up directly to the + & - terminals. My preferred way is to actually plug a 12v plug into the 12v socket, two ways that can go, a double headed one, which one side plugs into the socket and the other into the vehicle's socket, letting the car's charging system do the job (which is actually quite quick on the lead acid batteries). the other is a single headed one that you interface with your 12v battery charger. There are endless variations on this theme. Lead Acid batteries are easy to charge and very rarely blow up, unlike Lithium based batteries. They need a specific kind of charger for the specific kind of Lithium battery.

BTW, I never pointed out the socket for the 12V it is a Marinco marine socket (has a water resistant cover).

Something like this:
Socket

I have been dealing with the remote charging issues longer than most folks, so my solutions are evolving as tech gets better. I also have a bit of Yankee cheapness, "What! How much! I can make it better for a fraction of the price!" Your questions are fine. If not asked folks remain confused. Perhaps others have made similar, albeit better versions of this.

Double headed charging cord:
IMG_7126.jpg
 
Sorry, Fixed that link to the USB charger socket. If you don't want the stereo output, then the amp and speakers are indeed redundant. You just need the battery of your choosing, dimensions would be your guide along with price. As for the LiFe batteries. I only briefly looked into them. I would have to also get a charging system for that kind of battery. This one I have is healthy so it will be a bit before I get a new one and by then we may have portable fusion reactors. SO to charge this, two ways, one; pop the top and put a battery charger or trickle charger hooked up directly to the + & - terminals. My preferred way is to actually plug a 12v plug into the 12v socket, two ways that can go, a double headed one, which one side plugs into the socket and the other into the vehicle's socket, letting the car's charging system do the job (which is actually quite quick on the lead acid batteries). the other is a single headed one that you interface with your 12v battery charger. There are endless variations on this theme. Lead Acid batteries are easy to charge and very rarely blow up, unlike Lithium based batteries. They need a specific kind of charger for the specific kind of Lithium battery.

BTW, I never pointed out the socket for the 12V it is a Marinco marine socket (has a water resistant cover).

Something like this:
Socket

I have been dealing with the remote charging issues longer than most folks, so my solutions are evolving as tech gets better. I also have a bit of Yankee cheapness, "What! How much! I can make it better for a fraction of the price!" Your questions are fine. If not asked folks remain confused. Perhaps others have made similar, albeit better versions of this.

Double headed charging cord:
View attachment 165310
Excellent info!
So - do I have this right- the 12v port works both ways? It can use the power bank to send OUT power as well as take it in to recharge the battery?
The socket is something like this:

Also I’ve got a good trickle charger for my car battery already for checking battery & alternator and fast or trickle charge. Cool
 
Yes the receptacle is both ways, hot all the time to the battery. You can put a switch in to shut off power to the USB, but, the one I pointed out has its own built in power switch and you don't need an external switch. I now have two USB receptacles, one has a tiny volt meter built in. It needs a switch though or it will slowly drain the battery over the course of a week or so. The newer ones have a built in switch, mine is 5+ years old. It is something like this:
Old Style, no switch

New Style with built in switch

The USB-C port is only 20W so it would be really slow, but between the two you could do the RC Pro and the Mavic battery at the same time. They are just really cagey about giving actual specs of the devices. In many cases I find their claims a bit (lot!) overblown, so I returned the devices. I got this device a couple of years ago to see who is telling the truth. After a while you feel like the Amazing Randi, de-bunking the false claims. I find about 3/4 of the USB devices make false claims about their performance.
charger.jpg
 
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Thanks for this. I am afraid you’ve opened the door That will be hard to close. I have more questions… 😏

I like the usb/volt meter w/switch. I’ll probably include one on the box that I build, just for convenience, but I can see relying more on regular 12 V plugs. Given that the USB switches themselves are so overrated, doesn’t it make more sense to just plug a cube or a charging brick into a regular 12 V AC adapter?

Not as convenient is just plugging a USB cable into a port, but we would get the juice at the rate we need. I do that in my car sometimes rather than use a built-in, USB plug, I’ll plug an inverter with 2 normal AC outlet for my charge bricks. I’m not sure how strong the current is coming out of my built in 12v port, but I like to think I’m getting a faster charge.
I don’t know the proper search term for those outlets to add to the box. Trying to find one.

Also, where did you get this Mavic 3 battery charging tray?
***Nevermind. Found it…
1687003640485.jpeg

And- is this a good tester?
USB C Tester,KJ-KayJI 2 in 1 Tester Color Screen IPS Digital Multimeter(2022),Voltage,Cur,Pwr,Resistance,Elec,Temp,Capacity,Tme,Fast Charging,with USB Clip Cable Support PD2.0/PD3.0,QC2.0/QC3.0,BC1.2 https://a.co/d/e0pgcNC
 
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The charging block is off Amazon, cheaper on AliExpress, just takes 15-20 days to get it:
Charger
There are chargers that work off the 12V socket direct, they tend to be slower, at least the DJI one I had for the Mavic 2 Pro was. There is a ton of ways to slice this loaf of bread. Inverters to run an AC Adaptor certainly works, it is an inefficient way to do it though. Bestek and Allwei makes some nice inverters I have had reasonable luck with. Inverters seem to have a limited life span, for me at least.

For a straight Plug-In. I recently got this one, it seems up to the task, but all of these are dependent on what you car circuit to the 12V socket can do, some are only 5 amp, typically they are 10 amp, best if 15 amp circuits. Look in your owner's manual and see what size the fuse is. A 5 amp circuit will blow the fuse if you use this plug in:
Plug in
 
The charging block is off Amazon, cheaper on AliExpress, just takes 15-20 days to get it:
Charger
There are chargers that work off the 12V socket direct, they tend to be slower, at least the DJI one I had for the Mavic 2 Pro was. There is a ton of ways to slice this loaf of bread. Inverters to run an AC Adaptor certainly works, it is an inefficient way to do it though. Bestek and Allwei makes some nice inverters I have had reasonable luck with. Inverters seem to have a limited life span, for me at least.

For a straight Plug-In. I recently got this one, it seems up to the task, but all of these are dependent on what you car circuit to the 12V socket can do, some are only 5 amp, typically they are 10 amp, best if 15 amp circuits. Look in your owner's manual and see what size the fuse is. A 5 amp circuit will blow the fuse if you use this plug in:
Plug in
See- I don't have the correct terminology to ask the question. For straight plug in I was talking about a

120V 15A Female US Socket, Panel Mount to put on the box I want to build from an ammo box.

41jw430qkOL._SY300_.jpeg

I just meant put in 2 or 3 of these as well as the USB-c/USB-A ports. Would we get more voltage from this than the USB port or not?
 
Ok, let us go back to basic electricity again. These are 110V AC plugs. You would need an inverter to drive them. Each time you convert one flavor (AC to DC or vice a versa) you lose some of the electricity to inefficiency in the circuit, nothing is free. Think of it as trying to pour the water from your pitcher (the battery which has only so much power) into small bottles and you spill some each time trying to get it into the small neck of the bottle. It is the same in conversions from one type of electricity to another. Inverters are not very efficient and also use power just idling. So while yes you could get a higher power USB-C unit, let's say 100W. Most of the battery charging tops out around 70W give or take a bit. So 65W USB units, which are plentiful are close to the best you can get for output. Example, first pic is charging with a 100W USB-C supply which charges the battery at 66.12W, the second, a 65W USB-C supply is charging at a slightly less 63.96W, a difference of only 2.16W. So more is not always better. The 100W unit would use up your pitcher of water a bit faster than the 65W unit if you did the 12V DC to 110V AC to USB-C conversion, two steps of loss, aside form the wasted larger supply. So just going from 12V DC to USB-C only has one source of inefficiency loss and gives you within 3% of a 100W source.

100w.jpg65W.jpg
 

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