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Discussion Starter #1
After setting off from east London yesterday at 40% SoC I remembered I was passing Park Royal and the V3 chargers.

I started pre-conditioning, but only had 5 mins before I arrived.

At 40% SoC and with cool batteries I was not going to get full speed charging. On the other hand I had full regen, so I didn't expect battery temperature to be much of an issue. I plugged in expecting say 150-175kw.

I got 50kw.

I waited a few minutes, but that was it, so I moved to another charger, just in case.

Same thing - 50kw.

With enough charge to get home I gave up and left somewhat disappointed.

Were my expectations too high?
 

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Discussion Starter #3
Agree both those things weren't ideal for a top rate charge, but compared with the 250kw theoretical maximum, 50kw just seemed stingy :(

One other car when I tried the first charger, he had gone when I tried the second.

Are V3 shared like the regular chargers? I didn't look for charger numbers to see if they were labelled A, B etc.
 

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Discussion Starter #4
Another question that came to me today, should I have waited longer assuming the batteries would heat up as they charged, so after 5 mins I might have been up to a better charging rate (albeit the SoC would be higher and mitigating the heat advantage).
 

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Yes, the rate can build after a bit.

This seems very low, even for a cold battery.

Try it for a bit longer next time.
 

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Discussion Starter #10
In my case Performance.

I did charge once before at Park Royal, think I took a photo of the rate, will look back.

Does anyone know of a SoC versus expected rate of charge chart (other than the old ABRP one)? I guess you need one for each car model and charger type :(
 

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Discussion Starter #11
135777


Here is one I found from a test on InsideEVs, also seen on CleanTechnica.

Putting battery temp to one side (not properly warm, but not cold either) this table suggests I could have expected mid to high 100's.
 

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You cannot put battery temp to one side though, it is a rate limiting, I have a 22 mile commute to work that takes about 35 minutes on a normal day, i.e. 8 months ago before the apocalypse.

The cold battery warning (giving full regen) only goes away between when I come off the motorway at Slough and in the mile or so before getting to the office. I would not be expecting any like a decent charge rate until it is properly warm.

No idea how long you journey was to Park Royal but I wold be chalking that up to battery temp, there is a school of thought that lots of rapid acceleration and deep regen is better to warm up the battery rather than preconditioning.

However, I can imagine that being somewhat challenging in a M3P making your way through London! :ROFLMAO:
 

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there is a school of thought that lots of rapid acceleration and deep regen is better to warm up the battery rather than preconditioning.
With respect that isn't a great school of thought. Preconditioning actually warms the pack thermally using the battery heater so it is OK for it to take higher rates of charging and discharging. Doing fast acceleration on a cold pack isn't good for it, Tesla limit regen but don't limit the acceleration, perhaps for safety reasons or to stop people saying "it is slow". I believe that doing a lot of rapid accelerating on a cold pack is as bad as charging to 100%.
 

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With respect that isn't a great school of thought. Preconditioning actually warms the pack thermally using the battery heater so it is OK for it to take higher rates of charging and discharging. Doing fast acceleration on a cold pack isn't good for it, Tesla limit regen but don't limit the acceleration, perhaps for safety reasons or to stop people saying "it is slow". I believe that doing a lot of rapid accelerating on a cold pack is as bad as charging to 100%.
I actually think they do limit it, I sometimes see dots on the right-hand side if I ever try to accelerate hard with a cold battery and a relatively low state of charge, just in the same way you see dots on the regen side if the battery is too full.
 

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With respect that isn't a great school of thought. Preconditioning actually warms the pack thermally using the battery heater so it is OK for it to take higher rates of charging and discharging. Doing fast acceleration on a cold pack isn't good for it, Tesla limit regen but don't limit the acceleration, perhaps for safety reasons or to stop people saying "it is slow". I believe that doing a lot of rapid accelerating on a cold pack is as bad as charging to 100%.
Yes agreed, to clarify, I was not specifically referencing a cold pack, there are numerous mentions on Speakev which point to people saying they got better charge rates out of a bit of spirited driving on the way to the supercharger than they do from pre-conditioning. ie it raises the temperature of the battery more quickly than the pre-conditioning does.

So that point was not meant to be a recommendation for warming up a cold battery... It is however as has been mentioned limited by Tesla anyway, I think in my case the last bit of deceleration of the slip road and the associated regen is what takes the battery out of limited mode having had a fairly moderate drain on the motorway until that point.

If I want to get faster charge rate I stick on max-battery on my way there after a tip from someone on here, it works well to deliver improved charge rates, won't work from cold however as it will not let you select it when the car is stone cold, once again limiting the impact on the battery.

Generally not a problem as never using superchargers when cold, at the moment not using the car....
 

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Discussion Starter #17
When I get the chance I will do the trip in reverse, from Reading to London Fields, setting the Navi to take me to Park Royal first, so giving it as long as it likes to precondition. Will be interesting to see how much difference the temperature makes.
 

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I do just south of Reading to Slough, so from experience (and due to current 50mph restrictions) you should be warmed up by junction 6 even without preconditioning!
 

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Does wonders for efficiency on the way in during summer I could average 158W/m on the journey, due to the speed restrictions across pretty much all all of it, and that is in a Model S!
 
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