I have 3 sets of batteries, and while this might be good for most of my missions, I am considering buying a portable charger. Does anyone have any experience with these? Any that you can suggest? Here's one coming out in a couple weeks: https://www.amazon.com/River-EFTRW1-EcoFlow-Mobile-Station/dp/B072BY1G4Z/ref=sr_1_4?ie=UTF8&qid=1495938102&sr=8-4&keywords=Eco+Flow+Mobile+Power+Station. I've never heard of the company, but the product seems to be what I need.

Another option is this: https://www.amazon.com/dp/B01M3S ... ta=1#technical-data

Do a search, this topic has been covered many, many, many time before.

Thanks, Farnk. I did do a search - not only here but on Google. I found some stuff, but I wanted to see what other Inspire 2 users had used. Perhaps I'm using the wrong search terms: portable charging, portable charger. Didn't find anything from the last 6 months.

Indeed, the issue of field charging was discussed on every related forum 3784 times before ... In case of demanding Inspire batteries the best and most efficient method involves portable generator and suitable array of DJI power supply modules.  Unless you have access to a monstrous (say 200Ah) battery bank and DC/AC inverter carried in the trunk of your vehicle, no other power source will provide enough juice to charge Inspire/Matrice batteries reliably. River power supply may be good enough to charge single Phantom or Mavic battery perhaps 2-3 times, but not multiple sets of TB48's.     

I use a Cobra 800 watt inverter that is directly wired to my battery with 4-gauge wire. I have charged a P4 and a P4P battery on it at the same time. I have charged 2 Inspire 2 batteries on it at the same time. I have also ran a laptop, tablet and phone off of it at the same time. Going by the specs I should be able to charge at least 4 Inspire 2 batteries at the same time. This solution is tied to the vehicle, of course, but has worked well for me.

Cobra44Magnum Posted at 2017-6-1 05:59
I use a Cobra 800 watt inverter that is directly wired to my battery with 4-gauge wire. I have charged a P4 and a P4P battery on it at the same time. I have charged 2 Inspire 2 batteries on it at the same time. I have also ran a laptop, tablet and phone off of it at the same time. Going by the specs I should be able to charge at least 4 Inspire 2 batteries at the same time. This solution is tied to the vehicle, of course, but has worked well for me.

It's not about sufficiency of power supply, it's about the volume of stored energy. Another words, how many Inspire batteries (that's OP's dilemma) can be charged with available off-the-grid system? Your 800 W inverter will deliver enough juice to charge 2 Inspire batteries simultaneously, but would you be able to charge another pair later without re-charging your vehicle battery?

I've been using a cheap (sub £200) generator - the inverter type so safe for electronics which outputs 700 watts so is capable of powering around 3 or so DJI 180w chargers simultaneously. It's pretty quiet and efficient and relatively light at 8.5KG. Works well for me when I can't be near the car.

Dobmatt Posted at 2017-6-1 22:55
It's not about sufficiency of power supply, it's about the volume of stored energy. Another words, how many Inspire batteries (that's OP's dilemma) can be charged with available off-the-grid system? Your 800 W inverter will deliver enough juice to charge 2 Inspire batteries simultaneously, but would you be able to charge another pair later without re-charging your vehicle battery?

Definitely would be able to charge another pair. In fact the only battery issue I had was when I used the inverter all weekend for drone/tablet/phone charging without starting the car. I had to have a jump that Sunday afternoon to start the car. Depending on budget and assuming you can be in the vicinity of your car, a dual battery system with a switch would be the way to go. I had this in a cabin cruiser and it worked great. Run the inverter off of one battery and then switch to the other battery when it's time to start. Of course using a bigger battery will help also.

JBInspire Posted at 2017-6-2 02:21
I've been using a cheap (sub £200) generator - the inverter type so safe for electronics which outputs 700 watts so is capable of powering around 3 or so DJI 180w chargers simultaneously. It's pretty quiet and efficient and relatively light at 8.5KG. Works well for me when I can't be near the car.

If it's cheap, you're going to want to check if it's actually any good. Cheap inverters have a horrible sine wave and will destroy anything which is being used to drop the voltage back down, like a charging brick or a laptop.

If your inverter doesn't say 'Pure sine' I would bin it and buy a proper one.