Thought Leadership

The currents, levels, phases and stages of EV charging


Electric vehicles are often described as a revolution for the mobility sector. They look like their ICE counterparts but they’re radically different. Charging infrastructure is a large part of that and businesses around the world are taking advantage of this change. It's never been easier to diversify your services and income with EV charging, just look at airports and supermarkets. Knowing how it works can unlock the opportunity for you too. Without further introduction; here are the currents, phases, levels and stages of charging:


Alternating current (AC)

Alternating current (AC) is the flow of electric charge that changes direction regularly – it alternates. The alternated waves make the transfer economical but it’s not the fastest method of charging.  

Direct current (DC)

Direct current (DC) is the flow of electric charge in one constant direction. As the name suggests, this current takes the shortest route and results in a faster charge. DC doesn’t travel distances well like AC and require bigger machinery.  



Single-phase is the flow of electric charge through a single conductor/cable. This means that any change will have a direct impact on charging, as the voltage drops and rises so does the speed of charging.


Three-phase is the flow of electric charge through 3 or more conductors. This additional conductor/cable allows for as much as three times more power in a more reliable delivery.


The speed and rate with which you charge isn’t standardized, it fluctuates, and for good reason. Battery health is affected by charging. Three stage charging has been designed to maximize battery longevity and efficiency.

Stage one: Bulk

Bulk represents the first 80% of a battery’s capacity. This is the stage where the highest voltage and amperage will be used. 

Stage two: Absorption

Absorption is the last 10-20% of a battery’s capacity. This is where the voltage is maintained by the amperage drops. This means the remaining 20% is achieved without overheating the battery.

Stage three: Float

Float is the final stage of a battery’s capacity. This is where the current and voltage decrease further to ensure the battery isn’t pushed too far. The float safely maintains battery levels.


Since EV charging has a number of variables it’s commonly grouped into three levels.

Level 1

Your regular 120v home sockets fall into this bracket. The EV is connected like most of your home appliances. This means you can charge your EV in all sorts of places even if it is at a slow pace. You may have seen images of 50m cables hanging from 4th floor apartments, we don’t recommend that! The amount of kilowatt per hour (kwh) is based on a few things but on average a regular home supply will add round 50km in an eight-hour overnight charge.

Level 2

This is where things start to get more specialized, level two involves a supply that is directly connected to the grid, typically on a 240v circuit. This requires a dedicated hardware system like the boxes created by EVBox. This level can add 200 km of range during ad overnight charge.

Most businesses adding EV charging to their services provide this level. You’ll find level 2 charging at supermarkets, car parks, city centers and hotels. Using this level shows a commitment to fossil free travel as well as catering to customer needs.

Level 3

Level 3 is reserved for DC charging, this is the fastest option currently available, typically adding 80 to 140 kilometers in just 30 minutes. Up till this point, the levels have relied up an AC source then converting it to DC. With DC charging there’s no need for that, the process is more direct.

Level 3 is found at places where drivers are in transit, typically petrol stations and ports. In this instance you solve the pain point of needing fuel immediately. The goal is to get people to where they want to be.

If you’re interested in learning more, check out the rest of our blog. We have articles about industry abbreviations, event recaps and more.