It was a shared experience during the recent post-tropical storm Arthur power outages: the green battery bar on your cellphone, your only remaining means of communication with the outside world, slowly drains to red and then it’s lights out. But it doesn't have to be.

Adam Excell, in charge of products and services at the Halifax Mountain Equipment Co-op, says he’s noticing more customers relying on travel chargers to stay connected even when the power goes out

"Taking devices into the wild with us is becoming way more popular in that they have really great cameras attached to phones now and a lot of times it's just more convenient to just have one device,” he said.

"They're also really great products for power outages and those scenarios where we need that security blanket where we can call for help if we need it...Some people do come in and prepare for the storm and some people experience power loss during the storm and they'll come in afterwards for these kind of devices."

Excell says he expects the number and types of cellphone and tablet battery packs to grow quickly in the next few years.

Here are four power-free devices Excell says can get you through a storm:

1. Power Traveller Power Monkey: $90

Excell says this portable charger is MEC’s most popular.

  • Solar powered
  • It takes 10 hours of direct sunlight to fully charge the pack. It's designed to attach to a backpack and charge while you walk
  • Holds charge for up to a year
  • Regulates the solar energy so that it doesn't overheat your phone​

“The nicest thing is that it has an LCD screen on the battery pack to display its overall charge, which is great so that you know, so that you're never caught without power if you're depending on it,” said Excell.

2. Solio bolt: $65

  • Also solar-powered
  • Much smaller than Power Monkey

3. Eton-Boost Turbine: $63-$84

  • Hand-powered
  • A minute of cranking is enough for four minutes of talk time. So users have to crank for around 15 minutes to get an hour of talk and text time.
  • Compact

"They're not very efficient, but, in an emergency, they'll help you make a call with a dead cell phone,” said Excell.

4. Brunton Torpedo $38

  • This battery pack can be charged in a car
  • Holds enough to charge your phone fully

You can also conserve battery power by turning down your phone’s screen brightness and turning off power-hungry functions such as Bluetooth, WiFi and location services.

with files from Candyce Sellars