If an Arc’teryx Voltair backpack has enough battery power for more than 14 balloon inflations at room temp, it clearly has enough electrons for a few hours supplying low-demand ski touring accessories (provided ambient temps are not ridiculously cold). After a little time on Amazon and help from Electrical Depot, I lashed up this wiring harness for a USB connector mod. I tested extensively and it works fine, powering my phone while the pack is armed, and not interfering with inflations. (For the curious, I could also use the battery as a stand-alone charger for the phone if I ignored the warning lights the battery displays if it’s left switched on while disconnected from the pack.)
DISCLAIMER: This is of course only a proof-of-concept. We are in no way advocating modifying your ski touring safety equipment.
Following Delphi connectors from Electrical Depot
Delphi 480 12-10 Male Terminal (2 required)
Delphi 480 12-10 Female Terminal (2 required)
Delphi 480 2 Way Female Metri-Pack (housing, 1 required)
Delphi 480 2 Way Male Metri-Pack (housing, 1 required)
Delphi 480 housing seals (optional, 2)
Delphi 480 male housing snap-on wire cover (optional 1)
Waterproof Electrical Connector Plug with Wire AWG Marine (low current connector, water resistant, use any type)
Single USB connector USB voltage converter, USBbuddy is lower amperage, or use the motorcycle USB linked below as an Amazon item, it’s a 3 amp which will charge fast but probably draws too much power for efficient continous operation. The Amazon item is less weight, it’s what I ended up using.
Mini blade fuse holder and 3 amp fuse.
Assorted wiring supplies such as heat-shrink tubing, silicon tape, soldering iron and solder
Robust USB silicon or nylon braid charge cable, test in freezer for flexibility.
To do this right you need a Metri-Pack crimper. I didn’t have one so I hand-crimped the connectors and soldered them. In my opinion, even when properly crimped I’d probably give the connectors a touch with the solder. While this project is only proof-of-concept, it was useful in real life as it got me thinking about electrical safety with a battery pack this robust. Definitely, when using these electric airbag packs take care with the wires. Keep sharp metal objects far away, and inspect packing for stress on the cables. An electrical short could ignite you! Likewise, as with any LiPo battery charging I’d advise taking care with where the battery and charger are located, e.g., away from easily ignited materials and perhaps not left entirely unattended. Same precautions you should take with virtually all higher capacity rechargeable batteries, actually.