The e-Mobility Glossary: Discover the Language of a Rapidly Growing Industry

Jon Cooper

While e-mobility is not a new concept, it is yet to truly challenge the traditional automobile market. However, with its popularity on the rise and improvements to infrastructure making these vehicles an increasingly feasible alternative, its time may be closer than you think. We’ve put together a handy glossary of the e-mobility terms everyone should know to get you started.

But first… what is e-mobility?

E-mobility, or Electromobility, is the concept of using electric powertrain technologies to power and move vehicles. The most common examples include fully electric vehicles, plug-in hybrids, and hydrogen fuel cell vehicles that convert hydrogen into electricity.

Developed as a more environmentally friendly alternative to the internal combustion (IC) engine, this technology is likely to power an increasing percentage of new vehicles in the coming years.

The rise of the electric car

With the rise in popularity of manufacturers such as Tesla, the world is now very familiar with cars powered by electricity. But what about the jargon and technology that surrounds them?

Inside the car

Ampere-hours (AH)

The unit of measurement used to indicate the capacity (the maximum charge) a battery can hold (e.g., 200 AH).

Battery balancing

Battery balancing maintains the same voltage level across each battery cell, helping ensure they operate efficiently and enjoy a longer life cycle. 

Battery cells

A lithium-ion battery comes in different shapes and sizes – cylindrical cells, pouch cells, and prismatic cells. 

Bi-directional charging 

It’s a game of give and take – theoretically, some electric vehicles can store and return excess energy to the power grid when required, ensuring it doesn’t go to waste.

Depth of Discharge (DoD) 

Depth of Discharge is a measurement of how much a battery is emptied compared to its total compacity. The deeper its discharge, the higher its range, but the shorter its life expectancy. 

Electronic Control Device (ECD)

A component found in hybrid engines that connects the electric motor and the IC engine. It automatically switches to the optimum drive, depending on which is the most efficient at that time. Electronic power flow management ensures that the vehicle runs efficiently.

Energy density

The amount of energy that can be stored per unit mass or volume of a battery. It is expressed in kilojoules (kJ) or kilowatt-hours (kWh).

Inverter/inverter housing

The inverter connects the battery with the electric motor. The power electronics convert the DC voltage of the battery into high-frequency AC voltage, which forms the electromagnetic field for power generation in the electric motor.

Lithium-ion battery

A state-of-the-art energy source for electric vehicles. It converts electrical energy into chemical energy, which it stores until reconverting and releasing it as electrical energy when necessary. 

Peak output

The maximum possible output that an electric motor can achieve. It is comparable with the rated output of a combustion engine.

Permanent magnet synchronous machine (PMSM)

Just as combustion engines are separated by their use of petrol and diesel, electric motors are separated by the types of magnets they use. PMSM engines use permanent magnets, while electrically excited synchronous machine (ESM) engines use electromagnets. PMSM engines are far more common in Europe than the alternative. 

Power availability display

A display in the instrument panel of electric vehicles that shows both the level of power being drawn from the drive system and the power recovered while braking and coasting. It replaces the tachometer found in vehicles with a combustion engine. 

Power density

This defines how large and heavy a battery must be for a specified power level. The power density is determined by the materials used.

State of Charge (SOC)

Shows the remaining percentage of battery charge on the display of electric vehicles. It replaces the fuel display seen in vehicles with a combustion engine. 

Outside the car

Combined Charging System (CCS)

The CCS is an international charging standard for electric vehicles, though the preferred connecter differs from country to country. The CCS Combo 2 fast-charging connector is used in Europe, while the CCS Combo 1 connector is preferred in the USA. 
China and Japan each use a different standard entirely, as does Tesla.

Charge de Move (CHAdeMO)

The charging standard used in Japan – its connectors are not compatible with other standards such as CCS. 

Power electronic energy converters

This tool converts AC energy (used in national power grids) to DC energy (needed for car batteries). It will be found inside wallboxes, as well as in any publically accessible charging stations. 

Power dissipation

When a charging station converts AC energy to DC, the components used can release energy in the form of heat. In extreme cases, power dissipation can destroy devices, which is why charging stations will include an internal cooling system. 


A wallbox is a special wall-mounted charging station used to fully charge an electric vehicle within a few hours. 

The different drive systems

While e-mobility may technically refer to battery electric vehicles (BEV), we’ve taken the liberty of including all drive systems that serve as an alternative to the traditional internal combustion engine to help you get to know the different options. 

Battery Electric Vehicles (BEV) 

A BEV, otherwise known as a pure electric vehicle, fully electric vehicle, or all-electric vehicle, uses only chemical energy contained in rechargeable battery packs to power the engine, with no alternative power source. This means that unlike the other options in this list, a BEV will not contain an internal combustion engine, fuel tank, or fuel cells. 

Fuel Cell Vehicle (FCV)

Sometimes known as a Fuel Cell Electric Vehicle (FCEV), these cars are powered using fuel cells that generate electricity using oxygen they take from the air alongside compressed hydrogen, sometimes combined with a small battery or a supercapacitor. As these vehicles tend to emit only heat and water, they are considered a more environmentally friendly alternative to those powered by internal combustion engines and are often classed as ‘zero-emission vehicles’. 

Unfortunately, limited infrastructure, such as a small number of hydrogen refueling stations, has resulted in fewer customers and manufacturers adopting this technology than BEVs or hybrids. Whether this trend continues remains to be seen. 

Hybrid cars: The best of both worlds

Hybrid technology combines the benefits of an electric and internal combustion engine, making it a popular middle-ground for those seeking greener alternatives while maintaining the high range of a traditional motor. However, it’s important to know that not all hybrids are the same – take a look at the different kinds and what sets them apart. 


Micro hybrid

A micro hybrid uses an automatic start-stop system to recuperate braking energy and store it in a classic 12 V starter battery. However, the vehicle is driven exclusively by an IC engine, making it a questionable inclusion in this category.

Mild hybrid

Unlike micro hybrids, mild hybrids do have an electric motor in the drive system, as well as a 48 V battery to accompany the standard 12 V battery. However, this engine never works on its own and is used only to support an IC engine by boosting the engine during acceleration, for example. Fuel consumption tends to be lower than in non-hybrid vehicles.

Full hybrid

In a full hybrid, or Full Hybrid Electric Vehicle (FHEV), an electric motor and an IC engine can be used together or interchangeably. While it is possible to drive using only the electric engine, a low range tends to make it feasible only for very short trips. Unlike mild hybrids, full hybrids do not have an additional 48 V battery, opting instead for a high-voltage traction battery with several hundred volts, while the engine also tends to be more powerful. 

Plug-in hybrid

As the name suggests, the batteries of plug-in hybrids (Plug-in Hybrid Electric Vehicle, PHEV) can be charged using a charging station or a wall socket alongside the traditional recuperation system. 

Parallel hybrid

Parallel hybrids use two drive systems simultaneously or individually whenever required. With this type of drive system, the powers of the electric motor and the IC engine are added together.

Series hybrid

Series hybrids have an electric motor and an IC engine connected in a series but, unlike parallel hybrids, have a single drive system. The two engines will not be mechanically connected. Generally, the electric motor is used to power the vehicle, while the IC engine generates electricity for the battery.

Range extender concepts, in which the IC engine is used only to recharge the battery when it is empty until the driver can find a charging station, also fall into this category.

Power split hybrid

Both of the previous models can be combined in a single vehicle, known as power split or series-parallel hybrids. Here, it is up to the driver to decide which system they prefer to use.

Exciting times for e-mobility

2021 may well be the year that e-mobility becomes a driving force in the automotive industry, but it may also impact the future of the prototype casting industry. How? We dig a little deeper into this and other exciting trends right here.  



Interested in developing prototypes for an e-mobility vehicle and wondering if prototype casting is suitable for your project? Our ACTech team is always happy to help answer any questions you may have. We’d love to have a conversation.