Faraday Key Bag v Foil for spare Key fob use, just in case.
So I got my Faraday Key bag (about $2 on ebay or others) works better than foil (3 wraps) for sure.
The foil if put not about 1 foot away or so will still start the car.
The Faraday bag works even if put right near the push button.
So my opinion, cut a spare key ($3-5) hide it somewhere outside the car, then use that to open the driver door. Use your hidden spare key fob (battery installed) in a Faraday bag and use that once inside the car.
@019 Pacifica Touring L Advanced Safety Tech Group, S Appearance Package, Premium Audio Group, Key Sense, Uconnect 4C NAV w/ 8.4 " Display and Jazz Blue