High daily mileage

[bazhorn]

What do you wonderful EV sages think?

I have to cover approximately 130 miles a day with work so there will be a pretty heavy load of charging going on with my MG5.

I am awaiting a Wallbox 7kW installation, along with solar and a battery.

There's a 7kW Geniepoint at work.

I'm presuming, from what I read here, that leaving it on charge overnight, every night, which would always take it to 100%, may not be that good for the battery?

Would getting an Ohme smart cable and programming it to cut off at 80% charge (I'm sure there must be a way of doing that) be safer? Or are there any other options that would ensure optimum conditions for my eV battery?

Thanks in advance!

(BTW I can't seem to 'like' posts so don't get offended if there aren't any likes from me on your replies!)

 

[LoneRanger]

As far as I am aware the 20 % ~ 80% guidance is to protect the battery from sustaining a high cell voltage for too long. Too long being days or a week would be my understanding.
As you are using most of the capacity per day, I guess chemically the cells are getting a good an thorough range of use and it should do no harm.
I will bow to superior knowledge if anyone knows better.

 

[JohnB]

With home and work charging, you'll be fine. As for 100%. It's only really a problem if it gets left at that state for a while, you'll be using it straight away, so no issues there. You'll quickly find a routine that works.

 

[Petriix]

Charging to full every night will cause slight additional degradation to the battery in comparison to keeping it in the 80-20% range but it's not a massive deal. If you're planning on keeping it for a long time then it might be worth being a little more anal with how you manage it. The biggest damaging factors are excessive rapid charging and leaving it sat at close to full or close to empty for extended periods.

If you're going solar then I'd get something which can work with it like a Zappi, which also has timed charging and a 'smart boost' function. We cover about 100 miles on Thursdays so I set a boost to add 15kWh by 8am to get the car back to 75% when I plugged in yesterday afternoon. It took what it could from the solar yesterday then kicked in at 7kW at about 6am.

130 miles per day seems like an ideal use case for this car. The savings over buying fuel will be enormous.

 

[bazhorn]

Thank you all for your replies!

 

[Musicman]

Owned my MG5 since March and I’ve tried to stay cool about charging (4000 miles so far). Someone once said that you should treat your car like your mobile phone and I have taken that to heart. Unless I am doing a long journey (Notts to Cotswolds last Sunday) I keep the car between 20 - 65 some of which comes from solar on days like this and some from grazing at the shops. I probably only charge overnight once a week.

 

[Petriix]

As far as I am aware the 20 % ~ 80% guidance is to protect the battery from sustaining a high cell voltage for too long. Too long being days or a week would be my understanding.
As you are using most of the capacity per day, I guess chemically the cells are getting a good an thorough range of use and it should do no harm.
I will bow to superior knowledge if anyone knows better.

With home and work charging, you'll be fine. As for 100%. It's only really a problem if it gets left at that state for a while, you'll be using it straight away, so no issues there. You'll quickly find a routine that works.

To be clear: every single charge will cause some damage to the battery, as will every day that passes. That's just the nature of battery chemistry. The degradation is miniscule but will add up over the years. Some simple steps can reduce this slightly if you can be bothered. Most people probably don't want to have to micromanage it so plug in and forget is a great solution for them, but it's definitely suboptimal.

Every full charge wastes a small amount of energy (lost to heat during cell balancing and through reduced regenerative braking) and leaving some headroom means that you always have room for some free charging from solar or public chargers. So I tend to only charge as much as I need. At an average running cost of 1.4p per mile, it's working out quite well.

 

[Adee]

Owned my MG5 since March and I’ve tried to stay cool about charging (4000 miles so far). Someone once said that you should treat your car like your mobile phone and I have taken that to heart. Unless I am doing a long journey (Notts to Cotswolds last Sunday) I keep the car between 20 - 65 some of which comes from solar on days like this and some from grazing at the shops. I probably only charge overnight once a week.

I like my car and, unlike my mobile phone, I never feel inclined to smash it against the wall on a regular basis

 

[JohnB]

Imagine how long your phone would last if the battery was liquid cooled, and charge managed like an EV.

As for the chemistry, the main factors that influence degradation are: over temperature, run to 0%, charge to 100% (cell level, not pack. The BMS won't allow this, nor 0% strictly), storing at high/low state of charge, number of charge cycles, time.

Low temperatures tend to give a temporary drop in capacity rather than permanent degradation.

 

[Alb]

This is being over analysed IMHO.
Draw the parallel with ICE cars (of which there are millions).
Short journeys for example are deprecated but the overwhelming majority of owners pay no heed (and lose no sleep in the process!).
The usefulness of your car is degraded if you feel the need to worry about it every day.

 

[jamesie]

This is being over analysed IMHO.
Draw the parallel with ICE cars (of which there are millions).
Short journeys for example are deprecated but the overwhelming majority of owners pay no heed (and lose no sleep in the process!).
The usefulness of your car is degraded if you feel the need to worry about it every day.

Agree with this but having a charging "strategy" that suits your lifestyle and maintains the health of the battery as best it can is a good thing to have.

 

[JohnB]

This is being over analysed IMHO.
Draw the parallel with ICE cars (of which there are millions).
Short journeys for example are deprecated but the overwhelming majority of owners pay no heed (and lose no sleep in the process!).
The usefulness of your car is degraded if you feel the need to worry about it every day.

I agree totally. MG are confident enough to offer a 7 year warranty on a battery that it assumes will be given a really hard life. Any owner that shows even a hint of sympathy for it will be into double that. Around 25 years seems to be the current estimate for a liquid cooled pack in a temperate climate. The bodywork is almost certainly going to rot out from under you before the battery is on it's last legs.

 

[Petriix]

This is being over analysed IMHO.
Draw the parallel with ICE cars (of which there are millions).
Short journeys for example are deprecated but the overwhelming majority of owners pay no heed (and lose no sleep in the process!).
The usefulness of your car is degraded if you feel the need to worry about it every day.

I couldn't disagree more. Having all the information so as to make an informed decision about what to do can only be a good thing.

It's objectively false to suggest that daily charging to 100% will not cause additional battery degradation. Whether it matters to you or not is a totally different question.

I'm not going to criticise anyone for doing whatever they want with their car. If you're not interested in the analysis then that's fine; it seems that most EV owners prefer the simplicity of just charging to full. But that doesn't mean that there are no benefits to taking a more involved approach to changing.

I agree totally. MG are confident enough to offer a 7 year warranty on a battery that it assumes will be given a really hard life. Any owner that shows even a hint of sympathy for it will be into double that. Around 25 years seems to be the current estimate for a liquid cooled pack in a temperate climate. The bodywork is almost certainly going to rot out from under you before the battery is on it's last legs.

I believe the battery is guaranteed to have at least 70% capacity at 7 years. That's a massive drop in range. Some degradation is inevitable, but I believe that careful management could significantly reduce it. We're talking about the difference between 10% and 20% reduction in range over 5 years.

For me it's no bother. I plug the car in when I get home like most people. But it's just set to charge from the solar by default. If I need the extra range then it takes a minute to set a boost in the app.

 

[LoneRanger]

I like my car and, unlike my mobile phone, I never feel inclined to smash it against the wall on a regular basis

The car is great, I’ve had days recently where I could happily treat MG UK like that though

 

[Dave S]

What do you wonderful EV sages think?

I have to cover approximately 130 miles a day with work so there will be a pretty heavy load of charging going on with my MG5.

I am awaiting a Wallbox 7kW installation, along with solar and a battery.

There's a 7kW Geniepoint at work.

I'm presuming, from what I read here, that leaving it on charge overnight, every night, which would always take it to 100%, may not be that good for the battery?

Would getting an Ohme smart cable and programming it to cut off at 80% charge (I'm sure there must be a way of doing that) be safer? Or are there any other options that would ensure optimum conditions for my eV battery?

Thanks in advance!

(BTW I can't seem to 'like' posts so don't get offended if there aren't any likes from me on your replies!)

@Bazzhorn

I'm no expert - as previous replies to various threads will testify.

I'm using my car almost every day but not for as much as 130 miles journey each day.

What I do is, if I know that I'm going to use the car the next day for at least 20 miles, I fully charge overnight, and get the benefit of a full balance (I bear the scars of the BMS and having to rebuild the battery over many balancing sessions!).

If I'm not going to be using it much, I just make sure I've got about 60-80% in the tank.

The wiser amongst us will probably correct this philosophy!!

 

[Jomarkh]

@Bazzhorn

I'm no expert - as previous replies to various threads will testify.

I'm using my car almost every day but not for as much as 130 miles journey each day.

What I do is, if I know that I'm going to use the car the next day for at least 20 miles, I fully charge overnight, and get the benefit of a full balance (I bear the scars of the BMS and having to rebuild the battery over many balancing sessions!).

If I'm not going to be using it much, I just make sure I've got about 60-80% in the tank.

The wiser amongst us will probably correct this philosophy!!

I use mine daily for about 70 miles and top it over night to from 50/60% to 80-90%

 

[Prof1967]

I usually charge to 100% once a week. Based on current driving needs the charge may drop to around 50% in that time and I then top up.

I'm not too fussy about only charging to 80% as I only plan on keeping the car for 4 years and gave the backup of the 7 year warranty should the worst happen.

 

[Cocijo]

Battery health is a bit like the way most people treat their own health - they only really start to care and think about doing something about it when it’s failing.

 

[Lovemyev]

Battery health is a bit like the way most people treat their own health - they only really start to care and think about doing something about it when it’s failing.

A bit like improving your house security, with new locks and an alarm, after you have been paid a visit by the “Pond Life”.
Prevention is better that cure in my book.
The whole debate of battery health and how you can help it along, will always be a much debated issue.
Short term ownership on a lease deal or on a PCP deal and to be honest, you are likely to pay it no mind at all !.
It’s not your car effectively, so why look that far into the future ?.
Private buyers tend to be a little more respectful of the long term life of their packs I find.
The same could be said of rented houses.
There are some people that really look after them, others just end up trashing somebody else’s property.
A sad fact of life I am afraid .

 

[RoadUser]

We'll find out in a few years how the pack performs health wise as there'll be a lot of data, and not all of us drives and charges it the same way.