Speak EV - Electric Car Forums banner

1 - 20 of 22 Posts

Registered
Peugeot e-2008 GT-LINE
Joined
73 Posts
Discussion Starter #1
So I learned a nice tip today. When on a longer journey than your range rather than stop once for say 40mins plus, take a couple of shorter charging stops, that way your shorter 10-20 min rapid charges will be at full speed rather than tailing off to slower speeds after that period. Does anyone do this and find it better?
 
  • Like
Reactions: PaulD

Registered
Joined
4,693 Posts
Yeah. If it fits your coffee/bladder schedule and you can find a convenient, working charger with the facilities you require at the distances/times needed ... I'd do that.
But reality can be a b***ard :)
 

Registered
Peugeot e-2008 GT-LINE
Joined
73 Posts
Discussion Starter #4
The other thing little and often would help is less queuing for charges at busy times.
 

Registered
Joined
1,139 Posts
No, I aim for a working charger, charge to 94% and get home. Stopping takes time and I don't want to have to find another off route charger potentially blocked and broken.
 

Registered
Peugeot e-2008 GT-LINE
Joined
73 Posts
Discussion Starter #6
Yeah I get the reliability issue could trip you up, but in a quarter of the time time you can have 60% charge then move on and do the same again later so total time charging would be much less due to charging at maximum speed.
 

Registered
Kia Soul EV 2020
Joined
1,395 Posts
Tesla Bjorn has a huge advantage: he lives in Norway! TB's approach is the correct one for his conditions: lots of charging sites with lots of chargers and mostly reliable and he is well aware of his environment due to his experience.

In the UK, I would say we are long way from that. I would say the best approach so far is charge as much as you can whenever you can. One can start optimising strategies, only once the infrastructure improves.
 

Registered
Joined
8 Posts
I've been using the splash n dash technique on the BP Polar 150kW Rapids that happen to be on my routes, and as I'm getting more confident with the e2008 GOM (it's the trip meter miles per kwH that goes nuts when you charge, the GOM remains at a good guestimate) I'm starting to nudge it into rapid charge territory, arrive with SOC in the low teens & it'll suckle nearly 100kW for a while. Best to leave the charger at around 72% SOC in the e2008 when it drops below 50kW. As mentioned though, these 150kW rapids breed in pairs so there's a chance one will be working and maybe available (Weymouth, Ashington) unless they're around London where they'll be plagued by taxi drivers charging their 40kWh Leaf to 100% (hello Hounslow), but that'll change in time when their batteries fry.

On the single 50kW rapids I tend to charge into the slow zone more, aiming for 85-90% SOC before I move on. 50kW rapids are more suited to a longer cafe stop.

I'm still working all this charging out though, I've yet to make an expedition to the northern wastelands (Lancashire where I'm originally from), where 50kW single may well be the only available rapid.
Seriously, not even a nice Ionity charger would get me to go to Blackburn, but I may be swayed by the Intavolts at Booths whilst playing with the coffee grinding machine if they still have them.
 

Registered
Joined
630 Posts
This would only work if you stopped with a low state of charge, and moved on whilst the charge rate was still high. If you ran the entire trip well below a full battery, say mostly between 20% and 60%, then the charging stops would have to be more frequent, but they'd be more efficient than if you were stopping at 20% and waiting until you reached 80% before moving on.
Unless of course you had something else to do in that time, such as eat lunch.
 

Registered
Joined
1,139 Posts
Yeah I get the reliability issue could trip you up, but in a quarter of the time time you can have 60% charge then move on and do the same again later so total time charging would be much less due to charging at maximum speed.
Each car has different charging characteristics, so you have to factor these in. LEAF 40 is poor at multiple charges, Ioniq gets to 80% then 94% at a modest rate. With large battery cars, 60kWh, you have more choice than my meager 28kWh battery. Most people wouldn't even consider it a car with this range.
 

Registered
Joined
7,037 Posts
The theory of arriving with a low charge to enable a high transfer rate and leaving when the rate drops off - then repeating that fifty miles down the road - is sound if the aim is to shave a few minutes off the journey.

However, that also means that toilet stops and food intakes are rushed. Stops become stressful rather than relaxing as the trip turns into a mission. In my experience, such a strategy only suits a few situations such as travelling alone on a tight schedule. Family trips would result in friction if they were harried and rushed around in that way.

Then, as has been pointed out, you double the chance that a stop will have to be aborted due to congestion or broken down units.

I tend to take a mid-course. I stop with at least 25 miles range left to allow for plan B. Then plan to move on after 30 minutes but be prepared to extend that as required by circumstances such as long queues at the Costa counter that delay a pleasant coffee break. Life isn't all about Bjorns 1000km challenges and snacking on burgers in car parks.
 

Registered
Peugeot e-2008 GT-LINE
Joined
73 Posts
Discussion Starter #13
The theory of arriving with a low charge to enable a high transfer rate and leaving when the rate drops off - then repeating that fifty miles down the road - is sound if the aim is to shave a few minutes off the journey.

However, that also means that toilet stops and food intakes are rushed. Stops become stressful rather than relaxing as the trip turns into a mission. In my experience, such a strategy only suits a few situations such as travelling alone on a tight schedule. Family trips would result in friction if they were harried and rushed around in that way.

Then, as has been pointed out, you double the chance that a stop will have to be aborted due to congestion or broken down units.

I tend to take a mid-course. I stop with at least 25 miles range left to allow for plan B. Then plan to move on after 30 minutes but be prepared to extend that as required by circumstances such as long queues at the Costa counter that delay a pleasant coffee break. Life isn't all about Bjorns 1000km challenges and snacking on burgers in car parks.
Yeah I'm not saying cut your stop short just cos of your charge rate but the opposite don't stretch your stop longer just because of your charge. If your pitstop is just for a quick loo break pop it on charge and if you are back to your car after 10 mins get in and drive away and enjoy the hopefully faster transfer rate then further along you might get lunch and spend 40-60mins+ and get a near full charge. That way charging isn't dictating as much and your natural breaks each get a splash and dash.
 

Registered
Joined
4,693 Posts
Yeah I'm not saying cut your stop short just cos of your charge rate but the opposite don't stretch your stop longer just because of your charge. If your pitstop is just for a quick loo break pop it on charge and if you are back to your car after 10 mins get in and drive away and enjoy the hopefully faster transfer rate then further along you might get lunch and spend 40-60mins+ and get a near full charge. That way charging isn't dictating as much and your natural breaks each get a splash and dash.
That's the way we should be able to do it. One day chargers will be so plentiful and reliable we* will be able to do it.

(* but I doubt it will be in my driving lifetime.)
 

Registered
Joined
7,037 Posts
With seriously longer-range cars coming on stream almost monthly it won't be long before EV charging at MSA's will be like it is with liquid sales. Apart from business expense users who are unconcerned about prices most people only fill with sufficient dino juice to get them to a cheaper pump. Perhaps EV drivers would accept higher prices in return for convenience as long as reliability and access wasn't compromised. But they would probably still only load sufficient at that premium price to get them to a more economical outlet.
 

Registered
Joined
2,078 Posts
clearly charging eats into your average mph, and thus charging slower means a longer journey, but i wouldnt stop for only 10minutes on a long trip, because then the time taken to get off the road, into the charger and start the charge starts to become a significant part of the time taken.

I'd much rather stop, get a good decent fill up until the rate starts to taper, and then move on. Which ofcourse depends on the car and many other factors.

You also run the risk of only doing a short fill, then finding the next charger is broken or busy. An extra 15 or 20 minutes charging at the unit your already on, is clearly faster than having to wait for 30minutes (or longer) behind someone else charging up at the next stop, or having to slink off route with battery warnings trying to get to an alternative unit...

I think personally, i would only do a short stop if i was fairly sure a longer stop was coming up. EG if i'm planning on stopping for lunch in 30miles, know theres lots of chargers at the lunch stop and i'll be there a while, then a quick splash to get enough charge to reach that stop would make sense.
 

Registered
Joined
870 Posts
Absolutely yes but the value of this depends on the car and the charge curve.

Using this strategy I was able to make a 140 mile journey in my Leaf 24 Tekna with a total of 21 minutes charging time. This is too long of a journey to make a single stop unless you're going to charge to 100%. My first stop after 62 miles was only 7 minutes, boost from ~30% to 65% and move on (as the Leaf 24 charge rate already drops by then). The second stop was 37 miles later, and took 14 minutes (15%or so to 65%). The last leg of 42 miles arrived with 10%. With traffic as it was, the journey took over 4 hours anyway so these breaks weren't hugely significant to journey time (best ever on that journey in an ICE was 2hr 38).

Now with the Tesla 3SR+, which also has a charge curve that declines quite heavily then this strategy gives the best journey times too - but with longer hops between charges. I think that the most effective strategy with the 3SR+ is, assuming you're using unrestricted supercharger/ionity/etc, to charge to 70% and run down to 5%, with about 125-150 miles between stops. 5-70% takes 20 minutes (on a 120kW V2 supercharger - a minute or two less on V3 or Ionity) so 20 minutes charge stop every 2-3 hours.

However, there are cars that this strategy doesn't particularly help with. If a car maintains its full charge rate to 75-80% charge the need for this strategy reduces. Leaf 30 and Audi etron are two examples - the etron will do a solid 5-80% in 30 minutes on an HPC, with the charge rate not dropping until you hit 80%, and the Leaf 30 similarly doesn't drop away.

I think each car has an optimum "hop distance" - the distance between charge stops on an infinite journey to get the highest journey speed. For the Leaf 24 it's about 40 miles (10%-65%), for the Leaf 30 it's about 70 miles (10%-80%), for the model 3SR+ it's about 130 miles (5-70%). Of course, that assumes charger availability, that you're not taking longer to eat a meal, etc.
 

Registered
Peugeot e-2008 GT-LINE
Joined
73 Posts
Discussion Starter #19
So it's a case of learn your car's charge curve then when it slows move on so your charge it optimal, unless your break is longer due to eating etc then no harm charging as long as that break is.
 
  • Like
Reactions: Neilew

Registered
Joined
870 Posts
Exactly that.

Fastned publish charge curves for various cars they've tested. Here's their graph for the Leaf:
134069


You can see how the 30 keeps its charge rate up to 80, but the 24 drops as it goes. The Leaf 40 might well benefit from the same 65% strategy, giving it about 85 miles between "hops" (but of course rapidgate is another thing there - although I think that using this strategy might reduce battery heating).

It's easy to think about for a journey of infinite length, but real-world effects mean things are a bit different. There's the time overhead of pulling off the road to wherever the charger is, faffing with apps etc to get the charge going (Tesla saves the user 1-3 minutes of charging time here by being a simple plug'n'go, without farting about trying to remember you CVC code etc) which makes multiple stops more lossy. There's the simple matter of we don't go on journeys of infinite length - You need to look at the journey that you are doing and figure out what the correct strategy for that journey is.

In the example I gave of my 140 mile journey (from my workplace where I have charging available to my mother's house where I have charging available), it could theoretically be done in 1 stop in the Leaf 24 in summer by being very very careful, but the charging time to do so would be 20-30 minutes longer than a 2 stop. For a Leaf 30 the same journey is a solid 1 stop, and for the 3SR+ it's a no stop required (other than human endurance!). One thing about the way I did it was the stop at 62 miles - the next charger along the route was another 17 miles on, so I wouldn't make that gap reliably or without stress.

So yes, it's about understanding the charge curve and how it interacts with your journey and where chargers are available along that journey. Assuming that your e2008 is the same in this regard as an e208, then: Has anyone charged an e-208 on a 150kW charger? How was...
134072

Again, this suggests 65% as the time to move on. Using 5-65% on the e2008 should give you about 100 miles between charge stops, and 35-40 minute stops on 50kW chargers, 25 minutes on 100kW+ charger.

Edit: Of course, the real-world is that if your charge stop is 120 miles from your destination then obviously you just hang on a bit longer to 75% or so. If it's 150 miles then probably better to stop again for a 10 minute splash closer to the destination.
 
1 - 20 of 22 Posts
Top