A heat pump controller for use in a heat exchange system includes a computing device and a user interface coupled to the computing device. The sleeve and the thimble are disposed in the barrel. The first switch may be driven by a first pulse width modulated PWM signal and the second switch being driven by a second PWM signal. The lithium-ion secondary battery 100 further comprises, on the edge of the insulating layer 245, a molten part 246 where the resin particles are melted. The temporary fastener provides an instant load-release feature so that manual removal of the fastener is provided.