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@Tim Parkes have you looked at the capacity of your battery recently when fully charged? I don't use obdeleven very often but recently I looked and it was showing just under 30kWh when fully charged. As I had last over 32 kWh at some point early on I'm thinking the capacity is shrinking quite quickly and wondered how other people are finding things.
Probably a stupid question, but I'm too tired to go look it up now. Does temperature affect battery capacity or just it's efficiency and charging rate?

Edited to add...
Sod my inquisitiveness. A quick Google answered my question with this from Battery University

"The driving range of an electric vehicle between charges is calculated at ambient temperature. EV drivers are being made aware that frigid temperature reduces the available mileage. This loss is not only caused by heating the cabin electrically but by the inherent slowing of the battery’s electrochemical reaction, which reduces the capacity while cold."
 

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Temp does make a difference, but I don't think it makes 2+ kWh difference, which is how it is looking at the moment.
In the Leaf it seems to be the other way round, the SOH on leafspy goes up during the winter, as does the usable capacity.

I need to change energy suppliers and the Octopus Go tariff looks the best deal, but off peak finishes at 4.30am. The way the Golf timer works I would have to start charging at 12.30am each night and the car would sit fully charged until 9 each day. If the battery is degrading quickly already I'm not sure I want to add to that with the car sitting fully charged for several hours each night.
 

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And during those four and a half hours the battery would lose all the heat from charging and become stone cold too.

Sent from my SM-G950F using Tapatalk
 

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Temp does make a difference, but I don't think it makes 2+ kWh difference, which is how it is looking at the moment.
In the Leaf it seems to be the other way round, the SOH on leafspy goes up during the winter, as does the usable capacity.

I need to change energy suppliers and the Octopus Go tariff looks the best deal, but off peak finishes at 4.30am. The way the Golf timer works I would have to start charging at 12.30am each night and the car would sit fully charged until 9 each day. If the battery is degrading quickly already I'm not sure I want to add to that with the car sitting fully charged for several hours each night.
I believe all things being equal the batteries in both cars will react to colder climes in the same way,any disparity would seem to be in the measuring equipment?
To add we took delivery within a couple of weeks of each other,I have recently noticed a dramatic drop off in mileage achieved although all very short journeys, it’s not battery degrading I have only done 3100 miles and never run below 30 miles and only fully charged a few times . Pretty much 80/30 % charging . Car is garaged but this weather hits it hard.
 

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Every now and then I really wish I had an OBDeleven to look at some numbers. But I don't. And I'm not going to. Even though right now I really, really want to see what my battery is doing!

Car is garaged but this weather hits it hard.
Yep. Had two long-ish runs this week in very similar conditions.

The first was 182 miles in 0 - 2 degrees temp. 3.4 miles/kWh.

Today was a balmy 3 - 6 degrees. 273 miles. 3.9 miles/kWh.

I'm surprised how much more efficient today was. If the charger in Oban had let me charge to 100% I probably could have made it to Perth on one charge, which I did not expect to be able to do in winter.
 

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I think the damp makes a lot of difference. On cold dry days I am able to get a higher average than on damp or slightly wet roads. And speed, 70-75 uses considerably more than 60-65 mph. Last weekend I was surprised to see nearly 4mi/kWh when a few weeks earlier at a slightly higher speed on a damp road at night it was only just over 3mi/kWh

@dieselgate It isn't just the range that is dropping, it's the capacity of the battery as reported in obdeleven
 

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higher speed on a damp road at night it was only just over 3mi/kWh
:eek:

Even at 65-70mph on a very wet dual carriageway in the dark with heavy rain at around 2-3 degrees I've not seen any lower than 3.2 miles/kWh! And that was probably going faster than I should with the road conditions.

Sorry. Thread drift. I'll stop now.
 

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I think the damp makes a lot of difference. On cold dry days I am able to get a higher average than on damp or slightly wet roads. And speed, 70-75 uses considerably more than 60-65 mph. Last weekend I was surprised to see nearly 4mi/kWh when a few weeks earlier at a slightly higher speed on a damp road at night it was only just over 3mi/kWh

@dieselgate It isn't just the range that is dropping, it's the capacity of the battery as reported in obdeleven
Yes I understand that ,my guess is cold affects the battery in performance of mileage and storage capacity,the latter explaining why the mileage takes such a big hit especially in the first few miles.

I can start of with 150 miles two short trips of under 6 miles total and it's down to around 100,in the summer it's 130+ That's not just about heating and battery usage,thats a 150 false reading caused by the batteries increased resistance.
The battery is telling the charging circuit its full and it switches off the charge ,but its only 90% really,just the resistance to taking more charge is increased with the cold weather giving a false reading to the charger.

Your obdeleven is telling you that ,perhaps not that it will improve with the weather?
Just a thought!
 

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:eek:

Even at 65-70mph on a very wet dual carriageway in the dark with heavy rain at around 2-3 degrees I've not seen any lower than 3.2 miles/kWh! And that was probably going faster than I should with the road conditions.

Sorry. Thread drift. I'll stop now.
It would be unusual for the thread not to drift
I've seen 3mi/kWh a few times recently. Not really wet but in light rain and less than 5°C at night with ACC set at 75mph it climbs to 3-3.1mi/kWh after about 30 miles. When I pull onto the dual carriageway, less than half a mile from home, its about 1.5 usually.

@dieselgate yes obdeleven is showing the actual charge in the car. I'm interested in anyone else who has obdeleven and what their car is showing as 2kWh less already is slightly worrying. I was hope that @Tim Parkes or maybe @Jonathan Oates if he had the obdeleven dongle would have looked at their cars recently and would know what capacity is showing.

Even dropping 5% a year could make the car very awkward in the winter for my wife on her busy days next winter. She already has to charge when at home on her busiest day when it's cold and wet.
 

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With about 15 miles on my 35.8 kWh pack, OBDEleven showed 32.0 usable kWh (95% SOC right after charging at 7.2 kW, so I'm guessing the pack temp was above 20 C). Today, at 7,500 miles, OBDEleven is showing a calculated 30.1 usable kWh (58.8% SOC and 17.7 kWh indicated energy, battery pack temp was 13.5 C). I believe the colder temp is responsible for this as I have a hard time believing the pack already lost 2 kWh of usable capacity. I have only rapid charged three times since I purchased the car and have usually charged to 80% SOC. We'll see what OBDEleven indicates next spring.
 

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OBDEleven is showing a calculated 30.1 usable kWh (58.8% SOC and 17.7 kWh indicated energy, battery pack temp was 13.5 C).
Thanks for that, that makes me feel a bit better about my battery. We charge to 100% nearly every day and it has travel 19350 miles already and I thought I might be overworking the battery but there is very little between our two so maybe it is mostly temperature related.
Where do you find the calculated usable kWh? I've only been able to find the total capacity when the battery is fully charged, and lowest I've seen is 29.9kWh. That's under the Gateway Module, HV-EM Energy Info which gives two amounts and both reduce as the battery % reduces. I didn't note the temperature that time.


Edits:
I've just had a look this morning and it says it has 31.2kWh in the battery, fully charged which is 96.8% overall pack charge and the temperature of the battery is 10.5°C
Looking back at my records the best I had was 33.2kWh on the 14th April at 96% pack charge and 14.9°C. On 5th May the it read 32.9kWh fully charged and 6 miles left was 1.07kWh left in the pack.
During August holidays I have screenshots of 31.4kWh at the end of the week, and the battery at 25°C. Two weeks earlier it was 30.9kWh. It looks like there is quite a bit of variation anyway and not really temperature related.
 

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By calculated, I meant I calculated the usable capacity: 17.7 kWh/0.588=30.1kWh. I think it would be more accurate to charge to 100% and read the energy content, or as was just suggested, drive the car to nearly empty and use the driving statistics to calculate used energy. It does seem there is variability in the capacity as indicated by OBDEleven. I suspect part of the variability has to do with significant figures used for the internal calculations of energy, as you will get a significantly different value if you use three vs four significant figures.

I am guessing that VW uses a conservative BMS algorithm so that battery life is prolonged, but at least in the USA manual, the only mention of battery health relates to not performing "frequent and consecutive" DCFC sessions. Lucky for me, as of now, I only make one 250 mile one way trip two times a year, though the last part of the trip is 50 miles up a mountain road that includes 5000 feet of elevation gain.
 

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At 100% SOC and 10800 miles:
30.4/29.45 kWh
9.5 °C
Thank you, very similar to mine then, although it's fluctuating rather more than I realised.

@f1geek I imagine the mountain road must be fun in the e-Golf, the very flexible power delivery must help.
The most I've rapid charged in a day is twice, but it does get a rapid charge most months. From things I've read an occasional rapid charge is probably good for the battery. VW do seem to be very careful with the battery management, another reason why I was surprised at a low battery capacity reading. I'm hoping it will be better than the Leaf, that's lost slightly over 2kWh in 4 years according to leafspy.
 

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I've just checked the battery charge level this morning when fully charged and quite pleased to see that it is at 30.5kWh. It gets charged to 100% for most of the week as my wife uses it every day. When I can I set it to 80 or 90% but thats only been once or twice a week most of it's life. During the summer and with having the Niro it has been charged less at the weekend recently and little less often to 100% but it will soon be back to normal charging.

I have refitted the kitchen recently and in the process of clearing everything out my little book with all my battery notes has gone missing so I can only find what is written in this thread for history.
The car was showing 31.7kWh when delivered but I know that increased to something over 32kWh after about 2 months, as the manual said it would.

If we work on max usable being 32kWh my battery has lost about 5% capacity after 18 months and 33800 miles. Compared to the Leaf and the figures reported from Leafspy that is quite good for those miles.
The Niro is being sold and I'm probably going back to ICE for our second car so the miles will continue to be added to the Golf reasonably quickly.

@Jonathan Oates I would be interested to see if your battery is similar, how many miles you have driven, how you have been charging it etc.as you are the only other person who is still on here and has the OBDeleven app.
 

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I've recently bought an OBDeleven since I'm mainly interested in watching the battery temperature in the summer when I drive to work. Where I live in Canada in the warm months it will get above 30c and my drive to work is 95% highway for about 35 minutes I've been pleased to see the battery only rises a few degrees above ambient under these conditions.

Exactly what value are you measuring for the battery capacity?

I also have a VCDS cable I've used for years but find the OBDeleven so much more practical.
 

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Exactly what value are you measuring for the battery capacity?
In the 'Gateway Module' tick HV-EM_Energy_information. It gives three values. The first one, High_voltage_battery_energy_information, seems to be the total usable capacity. When I got down to 3 miles left this was only showing a few hundred watts. If you look back through this thread I think my findings are all in there somewhere amoung my ramblings.
The last reading shows about 1000 watts less and then goes to zero, I think at very low battery warning. I have no idea what the middle one is for.
 

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In the 'Gateway Module' tick HV-EM_Energy_information. It gives three values. The first one, High_voltage_battery_energy_information, seems to be the total usable capacity. When I got down to 3 miles left this was only showing a few hundred watts. If you look back through this thread I think my findings are all in there somewhere amoung my ramblings.
The last reading shows about 1000 watts less and then goes to zero, I think at very low battery warning. I have no idea what the middle one is for.
OK, I'll have a look for that when I go into work today. The problem for me is I very rarely charge to 100%, maybe once every three months or so, most of the time I charge to 70%-80% as that gets me home with about 30%-20% battery left. I assume the only way to get the total battery capacity reading is when the battery is at 100%?
 

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I assume the only way to get the total battery capacity reading is when the battery is at 100%?
I haven't found any other way, and I've ticked most of the options on the gateway, charging and battery control modules.
We charge fully several times a week so quote easy to check really, but it does take a while. Your battery should still be quite high if you're looking able to treat it nicely, as long as the temprature extremes don't affect it more
 
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