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By Geoff Graham Image source: https://unsplash.com/photos/a-man-ispumping-gas-into-his-car-RI8SyIOg4EM A practical guide to EV Charging vehicles recommend a maximum charge of 80%, in which case they might start at 80%, end at 50%, then recharge back to 80% overnight. Because plugging in an EV only takes a few seconds, many drivers will do this whenever they return home, with the result that their car is always fully charged and ready to go, similar to how many people charge their mobile phones. A Level 1 charger is usually supplied with the car, but if not, it can be purchased for $150-250. Photo 1 shows a typical example. Note that this option requires a GPO near your car; for many apartment dwellers or people with no off-street parking, this is not possible. In that case, your only option is a public charger (described below). Level 2 chargers/adaptors In this guide, we cover the most common methods you can use to charge an electric vehicle (EV) from a slow charge at home to a fast charge on a long road trip. Included are some subtle aspects of EV charging that even a well-versed EV owner may not be aware of. W ith the current popularity of EVs, prospective buyers face a steep learning curve regarding how to “fill up”. For a petrol/diesel vehicle, it is simple: drive to a service station, open the flap, insert the nozzle and squeeze the handle until it clicks off. However, with an EV, you have at least four possibilities, and that can be confusing. Generally, the charging options for an EV are referred to as Level 1, Level 2 or Level 3 charging. These and more were covered in David Maddison’s article on EV Charging in the July 2023 issue (siliconchip.au/Article/15857), but that was more of a technology overview. In these pages, we will consider the more practical aspects for a typical motorist in Australia or New Zealand who is thinking of purchasing a modern EV. Level 1 chargers/adaptors These are the cheapest option. It is simply an adaptor between a standard 68 Silicon Chip home 230V AC mains power socket and the EV. They are called a charger, but they do not actually manage the battery charging; they just contain some safety circuits and a module that communicates with the car, which has an onboard charger. Still, in keeping with common usage, we will also call them chargers. The actual charger is in the EV; all modern EVs have a built-in AC charger that converts the incoming AC power to DC and steps up the voltage to a level suitable for charging the car’s battery. The charge time is dictated by the maximum current that can be drawn from a GPO, which is usually rated at 10A (230V × 10A = 2.3kW). For a typical EV, this means that charging from empty to full takes 30-40 hours. This may sound like an extremely long time, but many people drive less than 120km in a day, and that would only drain the battery to about 70%. An overnight charge will then easily return it to fully charged. Some Australia's electronics magazine These are essentially the same as a Level 1 charger but in a fixed location with a dedicated 32A circuit running back to the switchboard/fuse box. Using a 32A single-phase 230V AC supply, these can provide up to 7.4kW to the car, resulting in a charge time of 10-15 hours, three times faster than a Level 1 charger. Some EVs and Level 2 chargers will accept three-phase power and, if you have access to this, you can charge a little quicker. However, the benefit is small because the onboard charger in most EVs is limited to 11kW or less. For this reason, it is generally not worth the cost of installing a threephase circuit, even if your car and Level 2 charger can support it. In a typical residential installation, a Level 2 charger is a box that is mounted on the wall of a garage. There are also weatherproof versions if it needs to be mounted outside. They usually come with a charging cable (typically 3-7 metres long) and cost from $800 to $2000 or more. To this, you must add the cost of installation, which can easily exceed $1000. Photo 2 shows a typical installation, in this case a Tesla Gen 3 Wall Connector. The more expensive examples will interface with home solar panel controllers so that the vehicle is only charged when there is excess solar power. This means that the “fill up” cost is near-zero. Many people with an EV install a Level 2 charger on the basis that they have paid a lot for the EV anyway and siliconchip.com.au one of these devices is only a proportionally small expense. Obviously, they are also handy if you drive long distances every day. But perhaps their greatest advantage is that they allow you to benefit from the cheap electricity rates that are available at certain times of the day for a limited number of hours. For example, under the Australian government’s Solar Sharer Offer, you can get three hours of free electricity in the middle of the day (in some states and on some plans; note that those plans may [likely will] make electricity more expensive the rest of the time). With a Level 1 charger, you will only get a tiny charge in that time, but with a Level 2 charger, you can get enough to cover a day’s driving, and it is free! Most chargers and EVs allow you to specify a charging window so the car will automatically charge during these cheap times without you having to do anything. Photo 1: a typical Level 1 charger/adaptor for charging an EV from a standard mains GPO. Source: Harvey Norman Photo 2 (above): a typical Level 2 charger/adaptor installation, in this case a Tesla Gen 3 Wall Connector. It is weatherproof, so it can be installed outdoors. Public Level 2 chargers/ adaptors Some businesses and shopping centres have public Level 2 chargers in their car parks. They are also often found in small country towns. Typically, these cost 25-45¢/kWh to use. Sometimes, when a business wants to attract customers, they are free. Usually these chargers are rated at 22kW, but this is misleading because (as mentioned before) the AC charger in your EV will probably be limited to 11kW or less, so it will still take a long time to get a decent charge (typically 6-12 hours). As a result, they are only useful if you want to get a small-top up while shopping, sightseeing, or if you are staying overnight near one. Because of this, they are called Destination Chargers by Tesla. Public Level 2 chargers do not provide the cable between the charger and the EV, so this is something that you need to purchase if you want to use them. Prices vary over a huge range from $40 to $500, so be prepared to shop around and make sure that it is a Type 2 to Type 2 cable as required in Australia and New Zealand. There is a push for public Level 2 chargers to be installed on street power poles. It makes sense when you think about it; there is plenty of power at the top of the pole, and all it needs is a cable running down to the charger/ siliconchip.com.au Photo 3 (left): a public Level 2 charger (Circontrol Evolve Smart T) at the Cockburn Youth Centre in Western Australia. These chargers are often referred to as “BYO cable”, meaning that you must supply your own Type 2 to Type 2 cable to use them. Photo 4: two 350kW chargers, each capable of charging an EV from 10% to 80% in 18 minutes. Source: Chargefox Australia's electronics magazine October 2026  69 Photos 5 & 6: the Type 2 plug used by Level 1 and Level 2 charger/adaptors has seven pins, which include the connections for AC charging (single and three-phase) and communication signals to/from the charger. Photo 7: the CCS2 plug and socket is the standard for charging EVs in Europe, Australia and New Zealand. adaptor fastened to the base of the pole. The intention is to make it easy for EV owners who only have street parking and, if it becomes a thing, this type of charger will be installed in older inner suburbs where there is little offstreet parking. can deliver, with typical capacities of 50kW, 150kW, 250kW and 350kW. The most common are 50kW and 150kW, while Tesla V3 Superchargers are rated at 250kW. Typically, a 150kW charger will charge an EV in 30-45 minutes from almost flat, while a 350kW charger will Level 3 or DC fast chargers charge it in 18 minutes. However, only A Level 3 charger (more usually EVs with 800V batteries can charge called a DC Fast Charger) is a genu- that quickly (more on that below). ine charger because it delivers the Tesla owners can charge using dedhigh-voltage DC directly to the car’s icated Tesla chargers or public DC fast battery, bypassing the onboard AC chargers. However, the reverse is not charger. The vehicle still controls the true, as Tesla only makes a limited charging process by telling the char- number of its chargers available to ger the voltage that it needs, but it is non-Tesla owners. the charger that regulates the charging DC fast chargers are expensive to voltage and current. build and maintain, so you will not High-end chargers can deliver mon- find one in a home. Instead, they are umental amounts of power, up to 500A installed in shopping centres, dediat 1000V via a heavy-duty, liquid-­ cated EV charging stations, and more cooled cable. If your car can take this recently, petrol stations. They include enormous charge rate, you can be back the cable to plug into your car and on the road in as little as 11 minutes, typically cost 50-70¢/kWh. So a full almost as short as the time needed to charge will cost $35-55. fill a petrol/diesel car. You will find most DC fast chargers Admittedly, there are few EVs and in the suburban areas of major citchargers that can reach this speed, but ies and along major highways. If you regardless, all EVs will still get a very are going on a long country trip, you fast charge from a Level 3 charger. need to plan ahead to go from charDC fast chargers are rated accord- ger to charger according to the range ing to the maximum power that they of your EV. 70 Silicon Chip Australia's electronics magazine This is not usually a problem, as there are plenty of route-planning apps for your phone, and the internal GPS mapping function in most EVs will also do that for you. However, in central Australia you are out of luck, as there are almost no public charging facilities out there – that part of the country is dominated by diesel-powered 4WDs. EV battery voltages EVs are categorised by their nominal battery voltage, which can be 400V or 800V. The actual voltage will vary according to the state of charge, temperature and other factors, but 400V and 800V are used as nominal figures. Most EVs have a 400V battery. This includes Teslas and many BYD/VW models, while more premium vehicles like the Porsche Taycan, many Hyundai/Kia EVs and premium BYDs use an 800V architecture. The battery voltage is not important in the driving experience, but it can affect the charging speed when using a DC fast charger. This is because a DC fast charger is limited in the current that it can supply. An 800V EV will get almost twice the energy into its battery compared to a 400V EV when charging at the same charger for the same duration. 350kW chargers are an example of this. They are quite rare, but if you find one and have a 400V EV, your car will request 400V from it, and your charge rate will be limited to about 200kW. This is despite the charger’s 350kW rating, which only an 800V EV can take advantage of. Modern 50kW and 150kW chargers used by big network providers like Chargefox and Evie will deliver over 800V, so an 800V EV will also get a faster charge from them. Older public chargers and most Tesla proprietary chargers are limited to 400V. In this case, an 800V EV will compensate by presenting a 400V load to the charger, but it will not have a speed advantage. Charging rates With a DC fast charger, you don’t get the full power during the whole charging time. Instead, the car will instruct the charger to start at a high power and hold it for a while before reducing it to a lower level based on the battery pack’s temperature. When the car reaches an 80% state of charge (or thereabouts), it will siliconchip.com.au Photo 8: the 2024 model of the Hyundai Ioniq 5. Outside of the luxury brands, this car line typically occupies the higher end of electric vehicles. Source: https://w.wiki/SWAp (CC-SA-3.0) rapidly reduce the charge rate to a fraction of the maximum as the battery nears 100% capacity. This is designed to reduce the stress on the battery as it nears full charge. When using a DC fast charger, the last 20% of slow charging can add a lot to the overall charge time. This is one reason that many manufacturers quote their charge times as being from 10% to 80%, and we used the same convention when quoting charge times above. Protecting the battery from damage is also related to the maximum state of charge that you should use when charging the car. Many (but not all) EVs use lithium-ion batteries. During the charging cycle, lithium ions are transported through the battery’s electrolyte and are embedded into the graphite anode. This embedding causes the anode to swell slightly as it reaches a full charge, causing cracking in the anode, which will eventually reduce the battery’s capacity. For this reason, experts recommend that, as a general rule, you should limit the maximum state of charge to 80%. It is fine to charge to 100% if you need to go on a long trip, and many people always charge to 100% anyway but, for day-to-day running, especially when you charge overnight at home, 80% will help your battery retain its capacity. This advice mostly applies to EVs using lithium-ion nickel-manganese-­ cobalt (NMC) battery chemistry, but it is a good default policy, especially if you don’t know what chemistry your car uses. Some EVs use lithium-­ironphosphate (LiFePO4) batteries, and for many of those, the manufacturers state that it’s fine to charge to 100%. siliconchip.com.au Regardless, due to advanced battery management and modern battery construction, most EV batteries are expected to outlive the car in which they are installed. Battery preconditioning One subject that you might hear about when researching EV fast charging is battery preconditioning. EV batteries charge best at a certain temperature (usually 25-35°C), so when you need a fast charge at a DC charger, it helps to already have the battery near the optimal temperature. Modern EVs will heat or cool the battery for you, and most will even automatically start this process before you arrive at a DC fast charger (when you have selected that as your destination in the car’s navigation system). It is not a problem if you have not preconditioned the battery before you start a fast charge, as the car will regulate the charge rate accordingly, but it might take longer to charge. For most Australians, this is not a concern, as the weather is generally warm. However, if you live in Tasmania or New Zealand, the very cold winter temperatures can make using a DC fast charger rather tedious without preconditioning the battery. Plug types In Europe, Australia and New Zealand, the standard connector for EV charging is the CCS2 (Combined Charging System Type 2) plug/socket. You may see some older standards (such as CHAdeMO) still around, but they are rapidly being phased out. The CCS2 connector (shown in Photo 9) consists of two sockets: the upper socket (with seven pins) carries the connections for AC charging (single Photo 9: the CCS2 socket in a Hyundai Ioniq 5. The upper socket carries the connections for AC charging and communication to/from the charger, while the lower socket has two heavy-duty pins for DC charging at up to 500A and 1000V. Australia's electronics magazine October 2026  71 and three-phase) and communication signals to/from the charger. The lower socket has two heavy-duty pins for DC charging at up to 500A and 1000V. AC chargers (ie, Level 1 and 2) only use the upper socket, as this provides all the connections and signals that are needed, and the lower DC charging socket is ignored. DC fast chargers use both sockets, with the upper socket only used for communicating with the car. In most cars, the DC socket is protected by a removable cover, as it is rarely used. One thing to be aware of is that there are many plug types and standards around the world. For example, China uses GB/T, and North America was using the old CCS1 standard, but is currently migrating to NACS (North American Charging Standard). This can be confusing if you are following foreign reviews. Be careful when purchasing cables and other charging-related items from overseas, as they may not work here. Conclusion Most people with off-street parking and easy access to a GPO socket will find that charging their EV is cheap and simple. An EV differs from a petrol/diesel car, where you typically wait until the tank is almost empty before driving to a service station and filling to the maximum (or refill opportunistically when you pass one). With an EV, it only takes a few seconds to plug it into your home charger, so waiting until empty is not necessary. You just plug in when you return home, and you will always have a ‘full tank’ in the morning. Because of this, many EV drivers with home chargers rarely see their battery charge fall below 70% and range anxiety does not exist. However, drivers who must park on the street do not have it that easy. In this case, you will have to find a local public charger and, because an EV has a similar range to a petrol/diesel car, you will be doing this with roughly the same frequency as visiting a petrol station. It might sound complicated using a DC fast charger on a long country trip, but in reality, they are easy to use – you just rock up and plug in. The car and charger will take care of the complications. Charging can take an extra 30 minutes or more compared to filling a petrol/diesel car, but after a long time behind the wheel, most people will take a break for a coffee or snack, anyway. So it is not a great burden. About the only time a petrol/diesel car has a significant advantage is if you are venturing into outback Australia or if you are doing a very long trip with no breaks, and you do not want to wait the extra 30 minutes or so when SC recharging on the way. Photo 9: this chart illustrates the charging characteristics of an 800V EV on a 350kW charger. The charge time from 9% to 80% was just under 18 minutes. The green trace shows that full power is only drawn for a short time; after it reaches 80%, the charge rate is drastically reduced. This is controlled by the vehicle’s battery management system (BMS). Source: nagapixels on Reddit 72 Silicon Chip Australia's electronics magazine siliconchip.com.au