Hi Jeffrey –
1. Yes, you can charge the V72 at the same time you charge your devices
2. We haven’t designed the case to accept another input from say a 12V DC battery, but we could potentially hack a cable so that the DC charger has a male 3.5×1.1mm connection with the waterproof plug. Email us at support@voltaicsystems.com with that request
3. Yes, you can fit two x V72s in the Nanuk 904 – There tends to be about a 30% loss going from battery to battery so 2 x V72s will give an effective charge of about 98 Watt hours which would more than fully charge the drone battery – however, nothing beats testing as the 30% is an average across a wide range of device tests

A bit more than two charges.

There is a loss going from one battery to the next (20-30%). Each V72 is 72 Watt hours and the Mavic is 43.6.

Hello, there can be 3 possible explanations for that. 1 is that the V72 is set to 16V or 19V by accident, while the car charger is expecting 12V. Please confirm the V72 is set to 12V. Second possible explanation is the drone battery always blinks the LED’s like that when the car charger is used. Can you charge your drone battery in a running car with the car charger to compare the blink pattern to the V72? and third possible reason is the LED’s blink in relation to how quickly the drone battery is charging, and the V72 might be charging it slower than the AC charger. In that case, it simply requires more time to charge than the AC charger but it will charge fine nonetheless. Feel free to respond via email to support@voltaicsystems.com for further questions. -Tony

I just received the Array solar backpack and it’s V72 battery pack. I tried to recharge my Mavic Pro battery with it using the Mavic Car charger adaptor but it doesn’t seem to work. The green led on the charger ,after a few seconds it’s connected to the V72 and the battery, will start flashing really slowly and the pattern of the battery’s led is not matching the intended “Charging mode” . Any ideas?

Hello, yes our V72 will still charge the Mavic Pro, we even have a customer who confirmed it works. Normally batteries do not require their max input amps to be able to charge, so even if the V72 charges it at a slightly slower rate, the drone battery will still accept power from the V72.

I measured 5 Amps going into the car charger adaptor of the Mavic Pro, which makes sense, taking into account the specs found in DJI site:

Input Voltage: 12.3-16 V (Sedan); 25-30 V (Coach)
DC Output: 13.05 V; 6 A; 78 W
Charge Time*: 54 min

will the V72 voltaic Battery be able to deliver that much current ( 5-6 A) ?? in the spec page it seems limited to 3.6 Amps….

Hello, thanks for pointing out a typo in the blog. The correct number is ~75%.

The reason a 72Wh battery does not provide a full recharge to a 68Wh battery is there are electrical inefficiencies that lose power along the way. A 72 Wh battery will not provide exactly 72Wh because of this loss, and a 68Wh battery requires more than 68Wh to full charge because of this loss. In total, we’ve calculated about a 30% loss from one battery to another from many different devices. That is how we calculated the 75%.