Charging to 100% When Cold

GeordieDownSouth

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Interested to know what people think, during the minus C days in the UK when ranges are impacted, do people charge to 100% if you car is a daily 100 miles a day car?

I get the 80% number is perfect for longevity, but if you use the car daily and it’s only sitting at 100% for 2 hours after charging finishes, in reality how much will this impact battery life considering we probably only get about 10-20 frost days a year down south in the UK?

I’m an avid mountain biker and have E-bikes so i understand lithium battery charging mechanics as i’ve been doing this stuff a while, i understand that sitting at 100% for long periods can degrade battery health but wondering if the car world is any different.

For clarity we have the 77kWh 2023 MG4 extended range.

Cheers
 
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Use the car as is appropriate for you. Charge it how it works for you.

Trying to fit “best practise for X” into your life when it doesn’t work for you will just fill your life with stress that you don’t need.
 
In the current conditions, for the days that I’m doing a commute (130 miles in total), I charge the night before to 100% so I have a comfortable headroom for pre-heating battery and cabin prior to starting off plus for extended use of lights and heating etc. Don’t see it as an issue since I’m driving it within a few hours of when charging has finished each time. I’m generally getting back home with 20-30% left in the tank and around 40 miles range.

By comparison, in the Autumn, 80% charge was more than adequate for the same commute.
 
In the current conditions, for the days that I’m doing a commute (130 miles in total), I charge the night before to 100% so I have a comfortable headroom for pre-heating battery and cabin prior to starting off plus for extended use of lights and heating etc. Don’t see it as an issue since I’m driving it within a few hours of when charging has finished each time. I’m generally getting back home with 20-30% left in the tank and around 40 miles range.

By comparison, in the Autumn, 80% charge was more than adequate for the same commute.
I charge to 100% every time from my 7.4kW home charger, the rational being that this reduces the number of times I have to unwind/re-wind my 12 metre charging cable!. I also don't believe that the charge rate delivered is likely to unduly degrade the battery,
 
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In the current conditions, for the days that I’m doing a commute (130 miles in total), I charge the night before to 100% so I have a comfortable headroom for pre-heating battery and cabin prior to starting off plus for extended use of lights and heating etc. Don’t see it as an issue since I’m driving it within a few hours of when charging has finished each time. I’m generally getting back home with 20-30% left in the tank and around 40 miles range.

By comparison, in the Autumn, 80% charge was more than adequate for the same commute.
Yeah that’s kind of what i thought, i do the same with the Mountain Bike, charge it to 100% a couple of hours before i leave for a frozen ride!
 
The NMC battery in the Trophy has a very low nickel content, so charging to a 100% isn't really that much of an issue. The LFP pack handles it better yes, but the NMC isn't that bothered by it either.

Edit; This took me a long time to find all the way back to page 22;

 
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I charge to 100% every time from my 7.4Kw home charger, the rational being that this reduces the number of times I have to unwind/re-wind my 12 metre charging cable!. I also don't believe that the charge rate delivered is likely to unduly degrade the battery,
Totally agree.
 
As the saying goes, there is no such thing as a free lunch, charging and discharging any type of battery is not 100% efficient, some electrical energy is lost as heat energy.
That means the cells are being heated internally as they are charged or discharged, the faster the charge/discharge rate, the greater the heat generated, but a slow charge has much less impact on the cells so less heat is generated, but some heating still occurs and in the case of cold cells, it's a good thing and will allow more capacity to be held in each cell.

T1 Terry
 
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In the current conditions, for the days that I’m doing a commute (130 miles in total), I charge the night before to 100% so I have a comfortable headroom for pre-heating battery and cabin prior to starting off plus for extended use of lights and heating etc. Don’t see it as an issue since I’m driving it within a few hours of when charging has finished each time. I’m generally getting back home with 20-30% left in the tank and around 40 miles range.

By comparison, in the Autumn, 80% charge was more than adequate for the same commute.
Do many people pre heat the battery in cold weather ?
I thought it was really used prior to fast charging to get the best charging rate...
 
A warm (enough) battery will allow electrons to flow better and so allow the car's motor to work better. Thus you can improve efficiency in cold weather by preheating the battery - but only if you do this whilst the car is plugged in, so the mains supply replaces the energy used in warming the battery. :)
 
A warm (enough) battery will allow electrons to flow better and so allow the car's motor to work better. Thus you can improve efficiency in cold weather by preheating the battery - but only if you do this whilst the car is plugged in, so the mains supply replaces the energy used in warming the battery. :)
I have intelligent battery heating switched on at the moment, does this warm the battery during scheduled charging🤔, or does it only come on when selected before a journey🤔

Interested to know what people think, during the minus C days in the UK when ranges are impacted, do people charge to 100% if you car is a daily 100 miles a day car?

I get the 80% number is perfect for longevity, but if you use the car daily and it’s only sitting at 100% for 2 hours after charging finishes, in reality how much will this impact battery life considering we probably only get about 10-20 frost days a year down south in the UK?

I’m an avid mountain biker and have E-bikes so i understand lithium battery charging mechanics as i’ve been doing this stuff a while, i understand that sitting at 100% for long periods can degrade battery health but wondering if the car world is any different.

For clarity we have the 77kWh 2023 MG4 extended range.

Cheers
We have experienced -8° here and have charged to 100% a couple times, mainly to balance the battery. This is my first winter with the ER and can see a marked difference in range mileage between the LR Trophy I had last winter. I usually charge to suit my daily use and during the cheap rate. I'm currently doing more than 1000 miles a month, above my yearly guesstimate, so I wouldn't worry too much.
 
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By my calculations 80% should be more than enough to support a 100 mile round trip even in winter and get there with more than 20%. I would be tempted to do 10 minutes battery preheating before leaving at negative temperatures. I haven't as my usual fault drive is short.

On my LR I normally charge to 70% during the week and for my long journeys go to 80-100% but try to keep the 100% trips to once a month. I will go to 90% rather than 100% when I need just a little more. I also try to use destination chargers where possible but will supercharge as needed during a journeys or where destination charging is inconvenient. I check new destinations in ABRP.

Other people don't have the temperament for that but for me I would be more worried by being blasé. Do what matches your temperament and individual requirements.
 
I do 160 miles a day and just use a super charger 80% is more than enough for that in very cold weather - 4 Driving mg4 trophy
 
I have intelligent battery heating switched on at the moment, does this warm the battery during scheduled charging🤔, or does it only come on when selected before a journey🤔


We have experienced -8° here and have charged to 100% a couple times, mainly to balance the battery. This is my first winter with the ER and can see a marked difference in range mileage between the LR Trophy I had last winter. I usually charge to suit my daily use and during the cheap rate. I'm currently doing more than 1000 miles a month, above my yearly guesstimate, so I wouldn't worry too much.
If you don't use DC chargers, turn off the intelligent heating.
 
Thanks 🙂, I pressed the tiny info button by IH switch and it tells you there that it helps speed up DC charging, but may shorten the range…every day’s a skool day 🙂
 

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