The Family Handyman To extend the life of your phone charger, remove the spring from a pen and stretch one end so it can fit around the charger cable. Wrap the spring around the cable, take a heat-shrinking tub, and slip it over the phone charger and spring. Use the lighter to warm the heat shrink tubing until it confirms to the charger and spring. To make your otherwise fragile phone charger last for more than a couple of weeks, try out this simple hack!