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What @molgrips said, plus EDIT (thanks @iainc for correcting my generalisation) regenerative braking in Tesla Model S, 3, X, and Y is reduced if you charge to >90% (or if it is darn cold). This effect may be different in other vehicles. If this affects your vehicle it makes driving electric a lot less fun as you’ll need to use the brake pedal to apply friction
edit. And as several have said, you don’t need to have a full charge most of the time. Especially if you charge at home. Why charge to the max if your driving will only use 15%?
^^^ the regen braking on mine isn’t affected by battery charge level.
More and more EVs like Tesla Model Y RWD and Model 3 RWD and Standard MG EV4 have Lithium Iron Phosphate (LFP) batteries which you are encouraged to charge to 100%
^^^ the regen braking on mine isn’t affected by battery charge level.
So if the battery is fully charged, what happens to the excess electricity? I notice this a lot as I live at the top of a hill.
I once scared myself in the Zoe not long after we go it when the regen didn't kick in when I was expecting it.
if the battery is fully charged, what happens to the excess electricity? I notice this a lot as I live at the top of a hill.
good question, I have no idea !
Question for those that have been through the charger point installations.
The wiring in to the mains, does it need to be pretty much wherever the fuse box is? Its quite a long way from the fuse box to where we can charge a car.
if the battery is fully charged
my guess would be that for those vehicles [edit] that have good regen when >90% charged [/edit] the battery is not fully charged. That while it says ‘100%’ there is some ‘spare’ capacity that can then accommodate the regen.
when we were testing various EVs a few years back the variability in regen braking between different models was wide. For example, Tesla - loads, Jaguar IPace - not much. This may be an influence in some vehicles?
does it need to be pretty much wherever the fuse box is
no. There are these ‘cable’ things that can transfer the electricity from the consumer unit to destinations around the property 😏
seriously, it doesn’t have to be very close. However, more than 5-10m and the cable costs will rise. And it is fat high current cable so not that cheap.
installers seem to favor installations as close as reasonably possible to the CU.
MG say the same as everyone else though on their website, which is 20-80% regularly??
Also looks like LFP are worse in cold weather and less energy dense so I guess there is a trade-off.
seriously, it doesn’t have to be very close. However, more than 5-10m and the cable costs will rise. And it is fat high current cable so not that cheap.
40m. tbh, this "cable" witchcraft your referring to. Was what i was querying about needing to go to the fuse box as I guessed just plugging into a 3 point wall socket wouldnt be ideal.
Im not even sure where wed run the cable, possibly mostly externally round the side of the house (from the front) along the garden wall to the parking spot at a guess. Internally would need a lot of mess making with a lot of century+ old features in the way. (Actually found part of the servants bell system the other day, the house IS NOT that big btw)
My leaf loses regn at 100% charge.
I suspect the excess electricity would shoot out the back as lightning sparks. A bit like tuned cars spitting flames.
I guess.
DrP
Was what i was querying about needing to go to the fuse box as I guessed just plugging into a 3 point wall socket wouldnt be ideal.
you can’t plug a wall car charge point into a regular socket. You can use a wall socket to charge. But with an upper limit of 13A it’ll be s l o w. [edit] and for a long run you’ll need some substantial cable for the extension lead to avoid overheating [/edit]
a good installer will be able to do this neatly for you. It will likely cost a fair bit for a complex 40m run.
servant’s bells? Found a whole bunch of the pulleys and cables for those in various parts of our house too. Sadly no associated features like bells or pulls.
What would be sensible would be for a software fix to add the appropriate level of actual braking in when the battery is full so that the car behaves in the same way. I thought I read that Tesla was doing this but I’m not sure it happens at the moment.
a good installer will be able to do this neatly for you. It will likely cost a fair bit for a complex 40m run.
That was my conclusion, I just wanted to be wrong 😀
servant’s bells? Found a whole bunch of the pulleys and cables for those in various parts of our house too. Sadly no associated features like bells or pulls.
Exactly that, seem some proper old school mains wiring too (exposed cables, no longer live)
old school mains wiring too (exposed cables, no longer live)
I was terrified when I found lengths of crumbly old rubberised cabling in floor voids, cellar, and lofts. Thankfully, like yours, none of it was live.
I would love to drive an ev down from Cervinia at 2000m down to Chatillon at 500m to see how much charge it would add. I guess there's some engineers or physicists on here that could do the maths?
@oldtennisshoes you might be able to get an idea using the ‘a better route planner’ app or website? https://abetterrouteplanner.com maybe you’ll get different results for different vehicle types too?
So if the battery is fully charged, what happens to the excess electricity?
My Prius and Ioniq just use the brake pedal as an indication of how quickly you want to slow down. They then use regen and supplement that with friction brakes as needed. So the effect of pressing the brake pedal is always the same. Generally you don't need to know the difference between friction and regen braking, unless you've got a BMW i3. Hyundai always behaves the same way regardless.
It may make a difference if you are trying to drive only on regen, with one-pedal, but that isn't really possible as you'd never be able to come to a complete stop. The Hyundai did allow you to drive on regen only but it wouldn't bring you to a stop so you still needed the pedal.
What would be sensible would be
for a software fix to add the appropriate level of actual braking in when the battery is fullto charge less so that the car behaves in the same way
Alternative option.
🤷🏻♂️ if this does happen with our 3 or Y due to some software update, charging all the way is something I’ve only felt the need to do a couple of times since 2018. ‘Filling up’ all the way just hasn’t been a thing.
I would love to drive an ev down from Cervinia at 2000m down to Chatillon at 500m to see how much charge it would add.
The potential energy available for that trip in a car + passengers of 1700kg is 25MJ which is about 7kWh. You won't get it all back because of charging efficiency losses but also air and rolling resistance. So work out how far the trip is, the efficiency you'd expect from your car if it were flat at a comparable average speed, and subtract that.
EDIT 18 miles, at say 40mph, probably only needs 4kWh to overcome friction. So you could probably gain 3kWh at most if you weren't using friction brakes into hairpins etc. Maybe 2 including generation and charging losses.
@Edukator does stuff like this in his EV, he lives in the mountains.
Potential energy is mass (kg) x gravitational acceleration (9.81m/s) x height differential (1500m). Ep = mas
Minus friction and generation losses plus the energy required to maintain a set speed (Ek = 0.5mv^2)
It's probably not that hard to figure out as its all fairly low level science l, you just need all the relevant data to begin with.
Batteries are primarily damaged by heat, when you charge to near 100% the internal resistance increases and (especially when charging fast) they therefore get hot. Is my simplistic understanding. Generating the heat also wastes energy which costs money.
My car slows the charge significantly past 80% and even more dramatically past 90%.
It’s also a courtesy/efficiency thing on public chargers. You can sit at one for an hour and a half going from 50 to 100% or drive a bit further down the road and do 30 to 80% in 20 mins. Of course that doesn’t apply overnight on your drive. But it seems a good habit to get into generally, so long as you’ve got spare range. I don’t usually plug in at home unless ours is below 50% (we get about 25-30% overnight at cheap rate on the 3 pin plug).
My previous ETron behaved very differently at close to 100% - no regen so you had to use the brake pedal more than normal.
My current i4 feels exactly the same at 100% as it does at lower charge. I don’t know whether it’s actually regenning at 100% or whether it’s using the friction brakes to give the same response but either way it’s nice to have a car that behaves the same all the time.
Our MG4 doesn't do regen when we charge it to 100%. As my better half found out in an incident with a tractor as she set off down the road 😉
@piemonster - we had to run about 25-30m from the fusebox that's at the back of the house to the charger at the front. We ended up being able to use some cable (of the right grade/condition) inside the house rather than running outside. Really we had no option, as the outside run would have meant very big/very expensive cables with quite a bit of voltage drop.
Also our electrician really didn't want to run it over the roof for all sorts of reasons. Mostly, it looks rubbish. I did think we were going to be into removing carpets and drilling joists, but we got lucky with a cable that had been put in for the extension near where we needed to be.
Batteries are primarily damaged by heat, when you charge to near 100% the internal resistance increases and (especially when charging fast) they therefore get hot.
They would get hot yes but cars communicate with chargers so they should actively reduce speed when the battery gets warm, which I think is what we see.
40m. tbh, this “cable” witchcraft your referring to. Was what i was querying about needing to go to the fuse box as I guessed just plugging into a 3 point wall socket wouldnt be ideal.
Im not even sure where wed run the cable, possibly mostly externally round the side of the house (from the front) along the garden wall to the parking spot at a guess. Internally would need a lot of mess making with a lot of century+ old features in the way. (Actually found part of the servants bell system the other day, the house IS NOT that big btw)
Having had a number of quotes for my wall box recently, most companies quotes were for a max 10m of cable. Anything over that was charged extra. I used chargedEV who had an easy online survey. Someone then phoned me back on a video call and did a walk round my fuse box and proposed charger point to discuss best options.
Just read that Leafs support V2G or V2H by virtue of having a ChaDemo plug.
Thought that was only some 40 or 60kwh leafs? And then only if you were part of a trial?
Thought that was only some 40 or 60kwh leafs? And then only if you were part of a trial?
I think it's technically possible, but it's not actually supported by energy companies. Not sure though so please prove me wrong.
Driving down from Avoriaz to Morzine I gained 4%. The way up took 8%. I found my general efficiency in the Alps to be better than on the Autoroutes.
The acceleration meant passing cyclists between the hairpins was much easier.
I'm not sure if anyone's following the Arctic Race of Norway but they were saying (while the peleton were going through a 7 km long tunnel and thus no coverage of the bikes) that it's the first bike race where all the support vehicles are 100% electric.
Xpeng are the suppliers of the cars, apparently. They had to bring some mobile chargers alone with them. I'm assuming they weren't simply diesel generators but rather pre-charged battery packs.
it’s the first bike race where all the support vehicles are 100% electric.
About time. I've aften thought EVs would be great for race support. Must be a relief for the riders not having to suck in exhaust fumes. I guess the motorbikes are still ICE?
it’s the first bike race where all the support vehicles are 100% electric.
I'm not sure there'd be enough range for the team and neutral support cars carrying 8 bikes on longer tour and giro stages.
All LEAF except the very earliest (2013 on, so for here it's the UK built ones) will do bidirectional charging - it's been in the CHAdeMO spec for very long time. It's just been very slow for the electricity network operators to get on board for trials.
As for 100% - it's absolutely fine to go to 100% if you're going to use the car again soon and bring it back down. It's just kinder to the battery to not leave it at very low or high states of charge for a long time.
I guess most evs have enough range for the stages themselves, but perhaps the transfers might be challenging.
I'd expect the biggest current problem would be the infrastructure. You'll have a large number of evs all needing charging at a new (often remote) stage finish each evening, at the same time.
I guess most evs have enough range for the stages themselves, but perhaps the transfers might be challenging.
I'd say not the ones with 8 bikes up top
I’d expect the biggest current problem would be the infrastructure. You’ll have a large number of evs all needing charging at a new (often remote) stage finish each evening, at the same time.
Yeah that's going to be a headache.
Xpeng are the suppliers of the cars, apparently. They had to bring some mobile chargers alone with them. I’m assuming they weren’t simply diesel generators but rather pre-charged battery packs.
That's quite an assumption. My money would be on some diesel generators being in the truck as a backup just in case.
What would be sensible would be for a software fix to add the appropriate level of actual braking in when the battery is full so that the car behaves in the same way. I thought I read that Tesla was doing this but I’m not sure it happens at the moment.
Lots of cars have it. Brake Blending. Arbitrates between all deceleration requests and then sends a signal to the most suitable device to slow the car down, brakes or regen. Some cars have a very simple system which just asks "available y/n" others can split accurately by individual device capacity. So you could have all 4 discs and both motors braking at the same time in some cases. It's also not easy to do well, so a lot of companies just don't bother.
They would get hot yes but cars communicate with chargers so they should actively reduce speed when the battery gets warm, which I think is what we see.
The box on the wall isn't actually a charger, the charger is in the car, the charger does the controlling. But other than that, precisely.
so though it says 100% on the screens it’s more like 90 something, to ensure battery life is optimised.
It's more like 97-98% of the batteries actual capacity reports as 100% to the driver, just to give a little breathing room for errors, climatic conditions/heating/cooling etc So not enough to actually protect the battery.
It’s more like 97-98% of the batteries actual capacity reports as 100% to the driver
I think that varies, perhaps by battery chemistry but also perhaps by the desire of the manufacturer to fluff up their range numbers. Some people have calculated based on the battery voltage reported on OBD2 and the known characteristics of the chemistry and come up with estimates that put the 100% reported capacity of a Leaf to be near 80% of what you would achieve in a lab. That sounds like a bit of a big margin though.
It’s also not easy to do well, so a lot of companies just don’t bother.
Yeah it's something that reviewers pick up on - wether or not you can feel the transition between regen and friction.
Test drove an MG EV4 yesterday and was favourably impressed so it may be appearing in our driveway soon.
Dumb question - as I mentioned previously we have an old charger that was there when we moved in. It has a tethered Type 1 cable. While we wait for a new charge point to be installed, can I use an adapter to charge the car via the Type 2 socket? Will I die? And more importantly, will the battery die?
Xpeng are the suppliers of the cars, apparently. They had to bring some mobile chargers alone with them. I’m assuming they weren’t simply diesel generators but rather pre-charged battery packs.
Same issue everytime there is a high number of EV chargers, the grid simply can't support it locally. There are a 1mw containerised battery storage units, but you've still got to charge it.
Doesn't have to be Diesel though, there are more an more options appearing: HVO (the easiest to get hold of), glycerin (Formula E) and then there are dual fuel options becoming available (hydrogen port injection).
Any big event will bring in temporary power, at many venues there simply isn't the power available and the amount of cost (£ and co2) it makes more sense to bring in the right amount, plus it can be pretty peaky along with the penalties for power outage.
Thought this was an interesting read…these cabins of batteries could be portable for events where generators have been used in the past maybe?
Would be useful for an event where some punters need a quick top up, but for something like the TdF when you have hundreds of vehicles all on empty, it might be too much. A generator powered by biofuel could work, but then you'd need a lot of fuel too. Not sure how much.