As fleets move towards adoption of Battery Electric Vehicles (BEVs), i’s important for fleet managers to have an understanding of the various plugs they will encounter on vehicles and on available charging hardware.
As a first step, lets cover the difference between AC (alternating current) and DC (direct current) charging, and this involves covering some fundamentals about electrical systems, as simply as possible.
All mains supplied power is AC, while all BEV batteries are DC. In order for AC current to be stored in the battery, it must pass through a converter. BEVs currently available have an onboard converter which is used for AC charging, and for DC charging the converter is in the charging unit. Each BEV has charging ports for both AC and DC charging, and Plug-in Hybrid Electric Vehicles (PHEVs) can have ports for both AC and DC charging, or just AC, depending on the make and model.
There are four different charging ports currently found on Australian vehicles, though due to the market having surpassed its VHS/ Betamax moment, the Type 1 and CHAdeMO ports (and corresponding plugs) are on the decline.
Charge points are at various locations on current market BEVs, so charger location and cable reach needs to be taken into account when planning charging infrastructure.
AC charging
Alternating electrical current, due to its need to pass through the current converter, often called the ‘onboard charger’, provides a slower charge, from 2.2kw from a 10amp powerpoint charger, to up to 22kW on a three phase system.
It’s important to note that most vehicles in Australia will take only a single phase charge (even from a three phase charger), limiting intake speed to 7.4kW.
Due to the onboard charger and slower charging speeds, AC charging may be better for long term vehicle battery health.
- Type 1 (SAE J1772 or J Plug): The Type 1 plug, originating from the U.S., was one of the first to appear in the Australian EV scene, especially with the introduction of early EV models. Supporting AC charging, this single-phase plug facilitates up to 7.4 kW of power. While newer models of EVs are transitioning to other standards, there are still some vehicles, especially earlier imports, which use the Type 1 plug.
- Type 2 (Mennekes, IEC 62196): The dominant standard in Australia, supporting both single-phase and three-phase charging, from 7.4kW to 22kW AC charging. All EV models available in Australia come equipped with this plug type, making it the only option for fleet AC charging purposes, and the standard for public charging.
DC Charging
Direct Current Charging, which has been converted from mains supply AC within the DC charging unit. DC charging can be from 24kW to 350kW, though this is limited by the charge rate accepted by different vehicles, and may also be slowed by a vehicles battery temperature and as a battery nears full charge.
DC charging is able to access the battery state of charge and other information from the battery.
When available, bidirectional charging, or V2X capabilities will be through DC charge ports.
- CCS2 (Combined Charging System): The CCS2 incorporates the Type 2 plug with additional DC pins below, thereby supporting both AC and DC fast charging. CCS2 is the standard plug for almost all EVs in Australia, including Teslas.
- CHAdeMO: Originally from Japan, CHAdeMO has found its way into Australia with Japanese EV models. Only the Nissan Leaf, and Mitsubishi PHEV models use CHAdeMO plugs, so it is a fair assumption that these will be entirely phased out at some point. Now, though, all public stations with government funding must continue to provide a CHAdeMO plug.
Megawatt Charging System (MCS)
The Megawatt Charging System (MCS) will be a standard for high power charging up to 3000amp, for large battery electric vehicles such as trucks, buses, ferries and aircraft which can accept a charge rate greater than 1 megawatt. Not yet operational, the MCS represents an industry global standard, developed by the charging industry association, CharIN.
Perhaps relevant now to fleet managers will be the standard that vehicles will have charging ports at hip height on the left of vehicles, behind the cabin door (for trucks.) This will help in the planning of future charging infrastructure.
