Be A Pro! | How To Get The Best EV Charging Speeds

[00:00:03]When you pull up at a petrol pump, your filling speed varies just like when you pull up to a shiny new 400 kW fast charger. Filling speed or for an EV, charging speed has always varied. It's just that you got so used to it with petrol cars, you barely notice it anymore. Let's find out what's going on.

[00:00:26]This is Dave Takes It On. I'm Dave and I'm going to give you both a really simple answer as well as a deeper technical explanation and it's all arranged in chapters so you can just skip ahead once you know that particular section. So start with chapter one, what controls filling or charging speeds.

[00:00:46]When you plug your EV in, you're ready for that lightning fast topup you've been promised and you get 80 kW.

[00:00:54]Not what you expected. But before you start complaining, you need to understand that the speed you can fill a tank with fuel also varies. Always has done, probably always will do. So I need to explain.

[00:01:09]Well, for petrol or diesel, the speed it flows into your tank depends on the car filler pipe size, the fuel nozzle size, the number of pumps at the station, the distance between the pump and the nozzles, the pump power and pressure.

[00:01:25]Now, the flow rate varies noticeably between different petrol stations and also HTVs have a far higher flow rate thanks to having no filler pipes, larger nozzles, and more powerful pumps.

[00:01:38]But that speed is strictly controlled.

[00:01:42]Try putting petrol in far too fast and it could instantly back up and spray out of the filler. It's highly dangerous.

[00:01:49]So, first, cars can only take in petrol safely within certain limits. And that is mainly controlled by the nozzle automatic cutff. Isn't it frustrating when you're in a hurry and it keeps clicking off all the time? Well, second, if your petrol tank is nearly empty, the automatic cutff allows you to fill up far faster before it starts clicking off than when it's very nearly full. Just trying to get that last few liters into a virtually full tank. It's really frustrating. You have to just gently squeeze the trigger or it cuts off.

[00:02:24]Click, click, click. Or third, when the petrol station is full, the speed the pumps operate at can slow down due to power or pump size restrictions. They've already noticed this on multiple occasions, but you usually just shrug it off or maybe vow not to use that station again. It's too slow. With petrol, you're so used to it, you barely even recognize it any longer. So, it's not just EVs.

[00:02:52]EVs in fact are no different besides taking longer. First for them EV charging speed is largely controlled by an AI powered battery management system BMS. That's our equivalent to the automatic cutoff. It's one job is to allow electricity to flow into the battery only as fast as it is safe to do so. There's no difference here. Second, our EVs fill or charge faster when the battery is nearly empty and really slowly when nearly nearly full. No difference here either. Third, our EVs can only get less power if the CPO, the charge point operator, has provided insufficient power to the charger, the site, or if the site is full. Hey, no difference here either. Chapter two, basic EV charging facts. Well, let's first look at a few quick basic facts for EV charging. Then we'll dive a bit deeper and then we'll see how we can all speed it up. Number one, as you use your EV, the battery pack voltage drops until it's effectively empty. Number two, all new EVs in the UK and Europe now have the same CCS2 socket installed as standard. Number three, all new EVs can be plugged into all public chargers which have CCS2 plugs. If your socket matches the plug, you can charge there.

[00:04:11]Number four, you can plug any EV into any power rating charger and the BMS will control how much you can safely get. Number five, an empty or almost empty battery will charge faster than an almost full battery, and that speed will slow down as the battery fills up.

[00:04:31]Number six, the charging process is a simple chemical reaction, and all reactions proceed faster if they're warm and slower if they're cold.

[00:04:41]Okay, all you tech nerds, if you know all this, you can skip to the next section if you want to.

[00:04:48]Now, the battery pack voltage never really goes down to zero. It just becomes so low, it cannot function the way it was intended. When the motor does not get enough power, it stops working.

[00:04:59]But the headlights or interior lights may continue working for some time.

[00:05:05]Number two, recently all new EV sockets and all EV public chargers harmonized to have CCS2 as standard. Just like even Apple has now abandoned lightning connectors and adopted the USBC as standard for mobile phones. Number three, it means you can pull into any public EV charger and plug in your new EV. Now, I say new because just like Apple and Motorola, certain EV brands once used a different standard. This case, Chado. While these older EVs are still out there, and some EV public chargers still have Chadamo plugs, no new ones are being sold only with Chado.

[00:05:42]Today, any new EV can use any public charger, just like any petrol car can use any petrol station. That's a bonus.

[00:05:49]Unlike petrol and diesel cars, you cannot put in the wrong fuel. We use electricity. It all just comes from the same national grid. Number four, your BMS will determine and control exactly how much power your battery can safely accept. It's perfectly safe to plug the cheapest and slow slowest charging EV on sale into the most powerful EV public charger in the UK. You already do this at home. See, one minute you plug in a 10W lamp, LED lamp, or a 2000 W toaster.

[00:06:17]Each device only takes what it needs and can handle. Number five, if the battery is almost empty, it can be charged really quickly. Imagine it like a multi-story car park. If that's empty, you can drive in and park really quick and easy. If the car park's almost full, you might have to drive round and round, up and down multiple levels, looking for the last few spaces. That takes longer.

[00:06:40]An almost empty battery charges very much quicker than a nearly full one.

[00:06:45]Nothing to do with the charger power.

[00:06:47]It's your BMS that's in control.

[00:06:50]Number six, charging a battery pack is a chemical reaction. And in chemistry, all reactions occur faster when warm, slower when cold. However, all batteries in the UK can safely handle the coldest of winters. It'll just be a bit slower.

[00:07:07]Number seven, many are confused with battery capacity measured in kilowatt hours, maximum charging speed in kilowatt, and efficiency measured in miles per kilowatt hour or w hours per mile. Now, the fact that your EV can drive and use 3 m per kilowatt hour or has a maxing maximum charging speed of 80 kW or when plugged in charging at 80 kW has nothing to do with how quickly you charge the battery. Imagine if the MPG you got out of your petrol car changes depending on how fast you can pump the petrol in. Ludicrous. Or you're getting better miles per kilowatt hour if you use an ultra rapid charger. These figures are totally unrelated. Chapter three, the public charger network. Well, petrol and diesel pumps normally have two types of fuel, standard and premium.

[00:07:55]EV public chargers have multiple different labels, level one, level two, and rapid. But essentially today, we have four definition based on charging speed or power. Slow, fast, rapid, and ultra rapid. The first two use AC electricity just like in your house.

[00:08:10]charge your battery pack using an onboard charger inside your EV, while the others use DC and run straight into the battery pack, bypassing the onboard charger. By the way, we call them chargers, but they're all nothing but a stable, protected, stable electricity supply. So, first you have slow. This is the charger that often comes with your car, which plugs into a standard 230 240 volt 3 pin wall socket, just like you plug in a toaster. It's also found out on the street and these typically charge at 7 to maybe down to 3 kW. It's the slowest method. It's often called trickle charging or granny charging for a reason. With slow, you can expect to add about three, four, maybe 5 miles of range per hour it's plugged in, depending on your EV. So, different EVs charge at different speeds, even using the same charger. For a full charge from empty on a modern EV, you could be looking at 40 or 50 hours or more. While this sounds crazy, it never happens.

[00:09:11]Many people who drive less than 30 m a day just plug in overnight and simply replace what they used while they're asleep. It's about convenience, not outright speed if you're asleep. Next up is fast. You need to realize that when they came out, they actually were fast.

[00:09:29]This is the most common type of charger for homes, workplaces, and public chargers. These run on 230 240 volts AC circuit. It is always professionally wired to the relevant supply. In the home, this is usually capped at 7.4 kW.

[00:09:46]In business and public chargers, they often use three-phase and they can operate between 11 kW and 22 kW. They're a lot faster than slow, typically adding between 20 and 50 miles of range per hour. This means for most EVs, you can usually get a full charge, even from an empty battery, overnight. Now, the exact time depends on your car's battery size and it onboard charger, but it's the workhorse of the EV charging world. It's what most EV owners use for most of their home charging, ensuring they wake up with a full tank every morning. Then comes rapid charging. These are DC chargers, but connected to a much more powerful electricity supply. While most home chargers are 7.4 kW, these offer anywhere between 25 and about 150 kW and they're rarely if ever found at home.

[00:10:39]Most are public chargers and can charge an average 50 kWh EV battery pack in about 30 to 45 minutes.

[00:10:48]Finally, we have the one everyone gets excited about, DC ultra rapid. That refers to the high power chargers you find along the main motorways and the charging hubs. These range from about 150 kW right up to 1,400 kW. Now, they're already in use, but for the moment, only electric HGVs, lries, uh, use them as no car can use more than about 400 kW at present. They are built for road trips. Unlike level one and two, which use AC power from the grid that your car onboard charger converts to DC for the battery, DC fast chargers do that conversion outside of the car.

[00:11:26]They feed DC power directly to your battery allowing for higher very much higher power and faster speeds. So these are the stations rated in kilowatt 150 250 400. Now in a perfect world they can charge a battery from 10% to 80% as little as 15 minutes. But this is where our central mystery begins. You see the number on that station is a maximum possible output that the charger is capable of producing. It's not a guarantee. And the reasons you really see that maximum are what we're just about to get into.

[00:12:00]So, chapter four, eight, eight reasons your EV charges slower than you expected. Okay, this is now the heart of the matter. Think of the charges advertising speed as a speed limit sign on a highway. Just because the sign says 70 mph doesn't mean you'll always be going that fast. traffic, weather, and your car itself. And your driving style will dictate your actual speed. It's the exact same with EV charging. So, factor one, the charger versus your car. Now, this is the single biggest source of confusion. A public ultra rapid charger might be capable of delivering 350 kW, but your car has its own maximum charging rate. This is built into the EV when it's manufactured. Can't be changed. You get what the manufacturer decides that you get. If your car limit is 80 kW, you can never charge faster than 80 kW, no matter how powerful the charger is. The car's battery management system, the BMS, is the boss, and it will only request as much power as it can safely handle.

[00:13:07]Many newer EVs use an 800vt system, which often lets them accept very high power levels. Other EV mainly use a 400vt system that might top out at a lower speed. Now although there is much more to it than that. So the first bottleneck is and always will be your car's built-in limit controlled by the BMS.

[00:13:29]Factor two is the charging curve and your battery state of charge. Now as described, your EV doesn't charge at a flat constant speed. It follows something called a charging curve. We rarely arrive at a charger with 0% state of charge. That's far too risky to running out and doesn't do the battery health any good. For most people, they will arrive between 10 and 20% remaining. When the battery state of charge is low like that, it can accept power very quickly. This is where you'll see your peak charging speeds. As the battery fills up past 70 or 80%, the BMS intentionally slows down the charging speed to manage the heat and pressure building up inside the individual battery cells. It is at this point you often hear the battery cooling system and fans kicking in. This is called tapering. That final 20% from 80% to 100% can often take as long as the charge from 10% to 80%. This isn't a flaw. It's a critical safety feature to protect your battery's long-term health, and it operates exactly like the petrol nozzle cutff as the tank fills up.

[00:14:40]Factor three, battery temperature. It's the Goldilocks problem. EV batteries are a bit like people. They have a preferred temperature range where they're happiest and most efficient. This happy zone is roughly around a comfortable room temperature for slow and fast charges, though. The ideal temperature for rapid ultra rapid charging can be a good bit warmer. If your battery is too cold, the chemical reaction inside slowed down and the BMS will limit your charging speed to prevent damage. This is why charging in the winter can feel painfully slow. A freezing cold battery might only accept 20 kW or fewer from a station that can deliver very much more. On the flip side, if the battery gets too hot, either from fast driving or the charging process itself, the BMS will also slow things down to prevent overheating, battery degradation. This is why many, but not all, modern EVs have a battery preconditioning.

[00:15:42]When you use your car's navigation to go to a DC fast charger, the car can automatically start warming or cooling the battery so it arrives at the charger at the perfect temperature for the fastest possible charging speed. Now, you control that. If you use it, you charge faster. If you don't use it, you charge slower. It's so simple. But on a technical note, there are many who claim that using preconditioning cuts your range. And it does, but to a very small extent. But if you don't use it and you arrive at a public charger and the battery is too cold, the BMS will simply turn on your battery heaters anyway.

[00:16:22]Just this time they'll be using power from the charger which you're paying for. And you also have to wait while it heats up. So your EV will use heating or cooling to protect the battery or speed up charging. Your choice is whether that comes from your battery on the way there or once you start charging slowly at the public charger.

[00:16:44]Factor four, the onboard charger for slow and fast AC charging. Now, this one is specific to charging at home or it's slow or fast public chargers. Remember how the car has to convert AC power to DC. The part that does this is called the onboard charger and it has its own power limit measured in kilowatts. And these power limits vary by model. You'll normally see ratings of either 11 kW or 22 kW, though some budget models have as low as 7 kW.

[00:17:14]Once again, if your car has an 11 kW onboard charge and you plug into a public level two station that advertises 22 kW of power, your car will only ever draw 11 kW. That's because its own internal hardware can't handle any more.

[00:17:30]It's another classic case where the station provides a ceiling, but your car sets the actual limit.

[00:17:38]Factor five, power sharing at the station. See, you pull into a charging site with two stalls. You plug in, you're getting a great speed, say 150 kW. Then another EV pulls in next to you and plugs in. Suddenly, your speed drops to 75 kW. You've just experienced power sharing.

[00:17:56]Many charging stations are deliberately designed to split their total power capacity between two or more individual chargers. A Tesla V2, for example, is a single charger with a single plug as 150 kW of total power. But that power is shared by two chargers next to each other. Likewise, a single grid surf charger might have 360 kW of total power provided, but has two plugs and can charge two cars simultaneously. In both cases, if one car is there, it can potentially get the maximum rated speed, but if two cars are charging, that total available power will be split between them.

[00:18:41]Now, elsewhere, a charger might claim to be rated at 160 kW, but that will often be measured at 400 volts. If you plug in an 800vt EV, some of them will simply double the volt voltage, but that's halves the current. Now, all these are common designs done to save money on both installation and running costs, but it's not universal. Many CPUs now prefer to provide the full power to each and every plug. And these are usually capable of providing the full maximum rated power even when really busy and even when 800volt EVs plug in. But that's not always sometimes again to save money many CPOS limit the total power supplied to the entire site because they calculated it will never be used totally full with every single car asking for the maximum the charger can provide. Imagine you're installing eight charges rated 200 kW on the site. The CPO should provide 1.6 megawatt total to the site, but calculate way half the cars on the road cannot even charge at 200 kW and those that can will rarely demand that uh as they arrive with a low status state of charge. The CPO might only install one one megawatt or less. If the site is never full or the cars using it can never charge at 200 kW, nobody might ever notice, but it is a major reason why your speed might be really slow or suddenly drop to half or below.

[00:20:14]Or factor six, the battery management system, BMS. Yeah, we've mentioned it a few times, but it deserves its own spot.

[00:20:20]The BMS is the brain of your EV's battery, and most now use AI to get the very best out of it. Its number one job is to protect the battery at all costs.

[00:20:31]It's constantly monitoring hundreds of data points, temperatures across the pack, voltage, current, the overall state of health, also the charger plug and the cable. Every single factor on this list is ultimately enforced by the BMS. If it detects any reading that's outside it program safe limit, it will immediately cut the charging speed to protect the battery or in an extreme case it will just cut the power altogether. The BMS always has the final word factor seven battery age and health. Just like us, just like the battery in your phone, an EV's battery will degrade slowly over time. As a battery ages, its internal resistance can increase, and it may not accept a charge as quickly as when it was new without overheating. The BMS also tends to get more conservative as the battery pack gets older, sometimes limiting peak charging speeds just to preserve its remaining health. This isn't something you'll notice overnight, and its effect varies a lot. Now, some have battery pack heating and cooling systems that are far more powerful than others. In fact, some early EVs had none at all, like the first Nissan Leafs. Others use battery cell chemistry that's far more tolerant to temperature variations. But a car with 150,000 mi on it might not charge quite as fast as it once did on day one.

[00:21:56]Factor eight, the charger itself. Yeah, finally, sometimes it really is the charger's fault. See, public charging stations are complex pieces of kit out in the elements getting used all day long, abused by certain people. They can suffer from broken components, software glitches, poor connections, uh, or they might just be in a derated maintenance mode. Sometimes a station advertised as 350 kW might only be capable at this time of delivering 50 because of either a fault or a shortage on the site electricity supply.

[00:22:31]The problem of unreliable or broken public chargers is a well-known frustration for EV drivers everywhere.

[00:22:37]Okay, that was a lot of information, but hopefully the mystery of slow charging is starting to make a lot more sense.

[00:22:43]Oh, by the way, if you're finding this helpful and you're far fully understanding why your car acts the way it does as a charger, do me a favor, just hit the subscribe button. We're all about making every part of EV ownership easier to understand, and subscribing makes a big difference to us on the channel.

[00:23:00]Okay, chapter five, your Pro Toolkit or how to actually charge faster. Okay, so now you know the why, let's talk about the how. Now that you know what slows charging down, here are five practical tips you can use to get the fastest charge possible out on the road. Number one, arrive with a low state of charge.

[00:23:20]Now, since charging is fastest when the battery is nearly empty, try to plan your stops when you're down at about 10 or 20% state of charge, not 50%.

[00:23:29]Arriving with a higher charge means you've already missed the fastest part part of the entire charging curve. So whereas you can pack a lot in quickly in the early days, now it's slowing down.

[00:23:41]So it's going to take you longer.

[00:23:43]Number two, use your car's navigation system to find charges. And this is huge. When you navigate to a DC fast charger using the car's built-in maps, even though you know exactly where it is, it will likely trigger battery preconditioning. Arriving with a battery pack at the perfect temperature can cut your charging town time down dramatically, especially in colder weather.

[00:24:07]Number three, embrace the 80% rule on the road trips. Don't wait around for the last 20%. The charge from 80 to 100% is painfully slow and usually not worth the time unless you absolutely need every single mile to reach your destination. It's almost always faster to charge to 80% drive. And if you have to stop again than it is to wait for a full 100% charge.

[00:24:32]Number four, know your car's specs. Look up your vehicle's maximum DC fast charge rate. If your car maxes out at 125 kW, there's no point going out and paying a premium for a super duper ultra fast, ultra rapid 350 kW charger. Number five, check for power sharing. When you pull up at a charging site, look at how the charges are arranged. if you can pick a station or a charger that isn't paired up and sharing power with another car that's already charging. Number six, different EVs charge at different rates and have different charging curves. I've downloaded a handful of real world tests on chargers rated up to 400 kW and a tiny number of easy EVs on the road today can get anywhere near that speed.

[00:25:16]So, congratulations to Lotus and Xbang.

[00:25:18]But I think these make the point. The shapes are amazingly different. Most fall away quite quickly. Some hold on longer before falling away. And one actually increases the speed gradually as it fills up. But all at about 80% see a dramatic fall off the cliff.

[00:25:36]Well, chapter seven, the conclusion. So that frustrating moment when you plug into a powerful fast charger only to get a fraction of the advertised speed. It's not a glitch. It's a complex dynamic process governed by physics, chemistry, and a whole lot of software and AI. All designed to protect the single most expensive part of your car, your battery.

[00:25:57]From the charging curve that tapers off of the battery fills to the critical importance of a Goldilocks battery temperature to the limit set by your car and the charger itself, you now understand the eight key factors at play. You're no longer just a driver.

[00:26:12]you're now an informed operator who can work with your car system, not against them.

[00:26:19]Well, the future of EV charging is always improving with promises of even faster and more reliable stations on the horizon. But with the knowledge from this video, you don't have to wait for the future. You're now equipped to get the best possible charging speed right now.

[00:26:37]And if this guide helped clear things up for you, please give this video a thumbs up. It really helps the channel. And I also do want to hear from you on the comment section. What's the biggest frustration you've had with public charging? Let me know your story in the comments below. Maybe you've hit your maximum limit. A lot of people don't.

[00:26:57]Anyway, see you in the next one. I'm Dave.