Here Are The Benefits Of An 800 Volt EV Architecture – Is It Really That Much Better Than 400 Volts?
Video welcome to the inside of the bmw ix m60 welcome to a charging station where i was just having a conversation with a viewer about 800 volt versus 400 volt, and i thought hey. This is a great video topic im just going to record this, throw it up right now and share some of my thoughts on why the 800 volt thing is thrown around a little bit too much and really the main benefits and disadvantages of having a higher voltage System in an electric car were talking pretty high level. If you guys want me to go more in depth with this, perhaps well get actual cars and do the real testing and show you everything were talking about. But these are my thoughts on why 800 volt doesnt need to be the end, all be all situation Music. So we are sharing just my thoughts on the 800 volt class of electric vehicles. For those of you who may be new to the topic, uh weve really seen this shift in two different classes of electric vehicle architecture in terms of voltage, and that would be a 400 volt class of vehicle and an 800 volt class of vehicle. Now theres. A couple things to keep in mind with both of these, the first is were typically talking about nominal voltage, which is the battery pack again high level, roughly around 50 state of charge, right in the middle whats, the voltage and uh. Of course, when the battery packs are dead, you might have a 400 volt class of vehicle down in the 330 340 volt range and full it might be 450 volt range, but keep in mind.
Voltage is quite dynamic across the entire uh discharge curve of the pack. That is not necessarily the case with lfp, which is why you need to full charge. Lfp cars, especially the way tesla. Does it but well save that for another topic, uh 800 volt class of vehicles are the same as well, which is sometimes when theyre full theyre. Like 780 to 820 volts and dead, they could be into the 600 volt range, so theres, really this range of voltage operating window that cars can be in and each is different and honestly to the general driving experience of the user. Big news: if you dont, want to watch the whole video if youre, driving and charging at home and just cruising down the roads, theres pretty much no difference between a 400 volt and an 800 volt car, they dont sound any different. They dont feel any different theres. No inherent advantages to just going into starbucks and back in the morning to having both, however uh there are. I guess well talk about that. Why 400 volt wasnt enough and why we needed this need for higher voltage cars, especially the expensive ones, are going with higher voltage the real, i would say, um contrarian, to that the the cars that dont fit. That mold are the hyundai kia genesis, e gmp cars, which, i would say are very reasonably priced for sort of next generation technology, but im driving a bmw ix at the moment.
That is not an 800 volt car. This is a 400 volt system architecture, its about 420, 425 volts full and about 340 330 volts dead is its operating window range and i actually think its totally fine. So here are the reasons that we needed a higher voltage architecture in cars and the first and the main one and the biggest benefit of higher voltage is dc fast charging you see when this car plugs into a dc fast charger. It requests 500 amps and again maybe you want to watch a little electrical, how this all plays out situation and maybe ill make a video on this topic. I know my dad on his out of spec. Dave channel will be breaking these down, but my videos are typically, for you, know, sort of nerd level. 9000 uh viewers like myself so were talking. You know this thing plugs in you hear me talk about all the time 500 amps. That is the current thats running into the car thats. What puts the pressure on everything and uh ccs? Typically uh? I dont actually know if its a hard coded limitation into the system, but generally the industry is, is capping 500 amps with our general ccs connector, which are on all these chargers here and um 500 amps is the amount of current were running through and that is Sort of regardless of the voltage that the car is at so when the car is dead, you plug in 500 amps at 330 volts, i dont, know whats at 160, 170.
Kilowatts is what youll get somewhere around there and then, as the car starts to charge a little bit. Naturally, the pack will have more voltage in it and it walks its way up to a peak of about 200. Kilowatts on this ix here comes an f 150 lightning, for example, relatively low voltage as well and so having a naturally higher voltage car for the same amount of current means, more power and so theres two ways to get a lot of power. Dump a ton of current in, however thats, typically inefficient things get hot theres, more heat loss, theres an equation, i squared r. That means for the amount of current that you run through as it increases on a logarithmic curve. You get more losses and so to reduce the amount of losses you can step up the voltage thats, why giant power transmitting lines are thousands and thousands and thousands of volts, sometimes hundreds of thousands of volts to get up there and um. You know to reduce transmission losses. Same thing applies here now. The thing is, if were capped at 500 amps. If you want faster charging power, you do need to go 6. 7. 800 volts up on the chargers. Not every charger can output 500 amps at 800, volts or 900 volts or a thousand volts, like sometimes lucid stuff gets into the 900 volt range, its really high voltage and so theres. When we start looking at charging graphs and things, the chargers themselves also have an internal charging profile, but were not going to nerd out on that were just talking pure benefit of 800 volt systems, and that is charge times.
We can charge faster. We can reduce the amount of current into the car which reduces the losses, however, that doesnt really affect the battery pack on a cellular level. The modules in the battery pack dont really know what the rest of everything theyre hooked up to so its not like theyre under any less stress its really all about the transmission losses of 800 volts. So when were charging the car, the cables might stay a little bit cooler at higher voltage. The connections may not get as hot and the dc pins into the car. All of those things. Those are the main benefit, but the battery pack itself still needs all the cooling to handle that power still needs all the right sort of balancing and and proper tuning to handle that much power, and so the battery pack itself isnt necessarily benefiting from 800 volts. Now you can have slightly smaller connectors in there. Your bus bars may not to be as big im talking generally high level again. Um theres also a benefit when driving the car with 800 volts. Although this is not as big of a benefit, i would say not enough to re engineer a whole 800 volt system architecture – and this is when youre talking about outputting power driving down the road, for example, lucid, really targeting max efficiency with hardware no cost spared they Wanted the best efficiency theyre going to be targeting the highest voltage possible to reduce the amount of current going through all of their cabling, all of their wires to reduce heat loss? Basically, the whole company of lucid, if i had to describe their architecture, design comes down to i, squared r everything was based around this equation.
Now. Okay, are there any benefits to a 400 volt car over an 800 volt car? The answer is not really other than cost cost is the big one. The other thing actually would be with some older charging hardware, specifically actually tesla superchargers those the hardware has a voltage cap a maximum and in order to charge an electric car, you need to match pack voltage and then dump current in you know, with a little bit Of variance, and so when were talking about charging at a tesla supercharger with a you know, sort of four or under eight or 500 volt maximum, and you pull up with a ticon. You have to use something: thats called a booster and theres three different types of boosters out on the market. Today the ticon basically splits its voltage in half and takes the amount of current that the charger can give and then steps up that voltage. Basically, a transformer in the car and thats relatively inefficient, quite heavy, a big expensive box and theres two options in taikon. You can do a maximum of 50 kilowatt or 150 kilowatt. Now that superchargers are opening up, i would actually recommend speccing the 150 kilowatt one um. The other way of doing it is the hyundai kia genesis, egmp way, which is theyre actually using the rear motor inverter to step up the voltage from these older charging. Hardware and again, i believe tesla v4 superchargers that are going to be doing ccs in america will be up to a thousand volts, but at least in europe theyre not um and theres.
Some like older evgo hardware, and things like this – that we need to step up voltage pretty much. Everything installed that youre gon na find can go up to eight nine hundred volts. This isnt that big of a deal, but i do think its important and whats cool about the egmp stuff – is rather than just splitting the packs voltage in half sort of cutting it like tycon. Does they say, hey charger, whats, your peak voltage and then the egmp cars just go hey that just give me everything you got and then itll rectify the power up into the battery pack using the rear motors inverter, and that means theres no unnecessary hardware, its just Using existing components and its such a smart design, thats the next generation of stuff – and it really shows how far out of the way hyundai kia went to make that system work really well, and so you know that would be really the only inherent advantage to a 400 volt system architecture would be to integrate nicely with existing charging hardware, but again this isnt much of a problem, and so okay, if 800 volt, is better. Why dont, we all use it and why isnt every car 800 volts and it comes down to cost a lot of cars. You use off the shelf components from third party suppliers to basically make their entire architecture go and the higher voltage components are a lot more expensive, theyre harder to manufacture and a lot of them just purely dont exist on the market.
So you have to give huge props to porsche. You have to give really huge props to hyundai kia genesis on egmp for basically saying screw it whatever we cant buy out in the marketplace, well, just design on our own manufacture and build, and that takes a lot of time. It takes a lot of money, takes a lot of engineering resources and ultimately, you have yourself a better product at a higher cost, and so you know this bmw ix to sort of bring the conversation back around um. This is a 400 volt system architecture that charges at 500 amps, so thats maximum really is about 200 kilowatts. The riving is the same way that can do about 220 kilowatts at 500 amps a little bit higher voltage than this car, and the only thing these vehicles would gain from having higher voltage would be a little bit more thermal longevity when driving hard, because, again less Heat loss things might not heat up as much. You would have a little bit better efficiency when driving, because i squared r – and you would have significantly faster charging assuming the battery pack architecture, the rest of it could handle now. Those three items – arent necessarily always the top priorities when engineering and designing a car and thats, why many of them are 400 volt system architectures. I actually think the sweet spot for most cars in this sort of area to keep costs in check and to keep it usable for consumers.
I think 200 kilowatts is pretty good for charging. Actually, i think the sweet spot is a high 400 volt car. You can use off the shelf components from third party suppliers that are typically rated up to 600 680 volts thats sort of that class level. So you can use off the shelf stuff at lower cost. You can, you know, still charge pretty well and of course, youre. Not really eking out every last drop of efficiency. Here you can just put another kilowatt hour in the battery pack or even less to make up the difference, its, not the end of the world. Now there is an interesting solution, which is what gm is doing with their ultim cars and specifically their double stack solution, which is all in the big stuff. So silverado hummery v with the big batteries and what theyre doing is theyre actually doing a parallel to series switch and theyre bumping. The voltage from about 350 volts nominal up to about 680 700, and that is when were getting into something pretty interesting. Because what theyre able to do for all of their driveline components for their dc to dc booster, for all the sub components in the car theyre able to keep those specked at a 400 volt class of component to reduce costs? And then, when they charge, they want to get all the power, so the battery pack, basically doesnt send power to any of those devices. Chunk. Voltage is now really high.
So now, when youre doing 500, amps at 700, volts youre getting all the power and a lot of chargers, cant actually even send the power to max out what a hummer ev could take. For example, its one of the fastest charging cars on sale same with lucid air, actually ill be testing one of those here shortly so keep an eye out for all the lucid content to come and uh there you go is 800 volt the end all be all No are there advantages, yes, is it always worth the cost for those advantages? No, not unless youre trying to build class leading stuff and thats. Why lucid went very high voltage were talking almost 900 volts thats? Why tycon is high 700 volts and egmp is really the exception. I would say of theyre, not cheap cars, ev6 ionic, five, not cheap at all, but thats. Again. All of the benefits of fast charging are from that 800 volt system architecture, but again those cars arent. Wildly efficient mostly down to their shape, really looking forward to ionic 6, which might prove to be very efficient as a long distance cruiser. So there you go. Those are my thoughts on 800 volt versus 400 volt. I think, were going to have this distinction. This class of vehicles coming in over the next few years – i think one day, of course well see everything, maybe move to higher voltage, but at least for now i think its fine either way.
But if youre looking for the pinnacle, youll go higher voltage, but dont roll up to a car show and be like my cars got 796 volts nominal and yours has only got 427 like it doesnt doesnt, really matter at the end of the day, thanks for watching Another out of spec reviews, video, let me know what you think down in the comments.