You order a cheap cable off Amazon or eBay and it never appears to charge at the correct speed anymore. USB chargers can impact how fast your device's battery gets back to 100%, but they're not the only determining factor. The wrong cable can slow down charging speeds as well. Redditor Esteef explains. USB cables have a data wire and a charging wire within the cable itself. Most USB cables, probably over 99+% are 28/28. Buying after market micro USB cables will pretty much always result in getting cheap quality 28/28 cables and your device will barely break 500mah when it charges, maybe even less.
As the temperature increases, some electrons move from valence band to conduction band. This gives rise to the conductivity. But, as the number of charge carriers are very low, covalent compounds are poor conductors.
Materials that are composed of atoms with free electrons are good conductors. Electrical energy is conducted through a material by the transfer of energy from one electron to the next. Materials that are made of atoms with tightly bound electrons are good insulators. These materials have very few, if any, free electrons available to transfer energy. The ability of a material to conduct electrical energy is called conductivity. All metals have high conductivity and are good conductors, while rubber, plastic, ceramics and glass have low conductivity, making them the best insulators.