A method (100) for assembling a portable device configured with an energy storage device, is disclosed. The method (100) can include: providing (105) a portable device with a controller configured to control the operations of the portable device; configuring (110) the portable device with a multi-mode switch including a temporary active mode configured for simplified testing, a temporarily inactive mode configured for minimizing power drain, and a permanent active mode for normal user operation; and controlling (115) the multi-mode switch from outside the portable device. The method (100) can help to prolong the useful shelf life of the device and can help to simplify testing and calibrating before shipping.