Charging has become one of the most present processes in our daily lives. But how many of us actually understand the intimate relationship between the charger and the device? I don’t talk deep physics here, just the basics: what, how much, how fast, and why.

Here is the starter’s guide to the charging process and technologies. Let’s dive in.

starter's guide to charging

Basic Terms

Ampere (marked A) indicates the intensity, which is the quantity of energy transmitted. This is what defines the charging speed. In modern devices, the receiving battery’s amperage determines the charging speed; the charger’s amperage can be higher than that and will not harm the battery at all.

Ampere-hour (marked Ah), or more frequently used milliampere-hour (marked mAh), is the charging capacity and is mainly used for power banks and batteries. It shows two things: a) how long will the battery live, and b) how many charging cycles it can take.

Watt (marked W) is the measuring unit for power and shows how much energy the device consumes. The number mentioned on the device you are to charge itself is the maximal amount of power it can consume; it’s usually less than that in real life.

Watt-hour (marked Wh) or kilowatt-hour (marked kWh) is the energy the device spends in the unit of time. This unit of power is the base for our bills’ calculation.

Volt (marked V) is the measuring unit for power “strength,” which is, in plain words, how much power the cord can transfer in a unit of time. It is essential to match your charger’s voltage with that of the device you plan to charge. Not paying attention to this may damage either of them.

The good-old “slow” charging

The general standard speed for charging the devices is now, with the fast or quick charging, referred to as slow charging or normal charging. It uses about 5W at max capacity when your device is extremely low on battery. 

slow charging


  1. It’s considered to be the healthiest charging method for the battery
  2. It applies to any rechargeable battery
  3. Relatively low cost


  1. It’s, well, slow 
  2. You do need a wire

The coming-standard “fast” charging

Fast charging is not something very new. It has been around for some years now. The point of fast charging is that it boosts up the wattage when your device is low on battery up to 15W in general, and then gradually goes down as it begins to fill up. By the end of the day, the difference is considerable only when it comes to a drained battery. The issue with fast charging is that it harms the Li-Ion battery. However, the main devices we use fast charging for are changed or upgraded too frequently for the fast charging damage to be that important.

fast charging


  1. It’s fast, much faster than traditional charging
  2. Allows having larger capacity batteries in portable devices


  1. It’s considered to kill your battery faster
  2. You need to make sure your battery is compatible with the technology
  3. You still need a wire
  4. Increases the risk of overheating the device

The new preference: wireless charging

Wireless charging is becoming more and more popular and widespread. And it’s easy to understand, dropping your device in a mat is a no-brainer. As with every technology, it has its ups and downs.

wireless charging


  1. No mingling with the cords
  2. Easy charging process
  3. Safer charging process


  1. The highest energy loss among the charging methods
  2. It is slow
  3. The device can’t be used while charging
  4. Not applicable for all devices

One-suits-all solution?

There is a wish and determination, especially in EU countries, to establish a standard one-suits-all solution for portable devices. This aims to reduce the e-waste, making having a different charger for every type of device meaningless. While the official one-for-all universal solution is yet to come, there is a number of universal chargers on the market, like the C

Energous WattUp

Multifunctional Chargers

Another type of charging devices that are gaining popularity is the multifunctional chargers. These can have a vast range of functionality, starting from any number of different chargers in one up to connectivity hubs that will also charge any number of devices. An excellent example of the last type can be the POWME 3-in-1 Wireless Charging Hub.

POWME 3-in-1 Wireless Charging Hub

Wrap up

There are many different and useful ways to charge your devices on the market today. All of them have their pros and cons and best usage situations. The trick is to find something that will fulfill your needs. This can become an endless chase with the ever-evolving technology, though the classical solutions will hardly fade away anytime soon.