MG's routine charging advice

[Staffex]

MG5 manual page 244:
High Voltage Battery Pack
Precautions and restricted conditions for use of battery
“When using the vehicle on a daily basis, it is recommended to fully charge it at least once a week, which is conducive to the health maintenance of the high-voltage battery pack…”

By ‘fully’ do they mean 100%? If so, this advice contradicts the received wisdom of charging to no more than 80% (even at home) unless absolutely necessary.

 

[slmorgan42]

#FL LR
In the FL manual it recommends 30-80% but ideally keeping it between 50-80%.

It says if you use the car a lot and are charging a lot (specially Rapid) you should charge to 100% to allow the the car to equalise the cells. I am sure in my FL manual it says do this once a month.

 

[Staffex]

#FL LR
In the FL manual it recommends 30-80% but ideally keeping it between 50-80%.

It says if you use the car a lot and are charging a lot (specially Rapid) you should charge to 100% to allow the the car to equalise the cells. I am sure in my FL manual it says do this once a month.

Yes, the advice goes on to state: "...every 3 months to half a year, a low-power (less than 10% or 1 grid) full charged (sic) is performed.". More advice follows on leaving the car parked or stored 'for a long time'.

 

[5teep]

MG5 manual page 244:
High Voltage Battery Pack
Precautions and restricted conditions for use of battery
“When using the vehicle on a daily basis, it is recommended to fully charge it at least once a week, which is conducive to the health maintenance of the high-voltage battery pack…”

By ‘fully’ do they mean 100%? If so, this advice contradicts the received wisdom of charging to no more than 80% (even at home) unless absolutely necessary.

The operative phrase there is "perceived wisdom". That's the trouble with the internet, everybody is an expert wether they know anything or not.
My car (SR) is charged to 100% every night, have driven 55k miles and do roughly 200 miles a day on weekdays, use DC chargers a lot and have not noticed any battery degredation in the 2 years I've had it. Every so often it does a balance charge of it's own accord.

My perceived wisdom is do what the manufacturer says and don't listen to experts (like me) on the internet

 

[slmorgan42]

This is from MG website. I thought it was in the manual but knew I had read it somewhere.

There are several tips that you can use to try and increase your electric car battery life:

- Charge the electric car battery between 20%-80% - The lifespan of the battery pack often depends on how much it’s charged. You can extend the life of the batteries by only charging them between 20% and 80% and trying not to let them drop below 50% too often. Going beyond these limits can increase the rate that the battery deteriorates over time.

The operative phrase there is "perceived wisdom". That's the trouble with the internet, everybody is an expert wether they know anything or not.
My car (SR) is charged to 100% every night, have driven 55k miles and do roughly 200 miles a day on weekdays, use DC chargers a lot and have not noticed any battery degredation in the 2 years I've had it. Every so often it does a balance charge of it's own accord.

My perceived wisdom is do what the manufacturer says and don't listen to experts (like me) on the internet

I tend to agree and go with what the manufacturer says

 

[Staffex]

I tend to agree and go with what the manufacturer says

I wrote received wisdom because many authoritative websites - including those of Li-ion battery manufacturers - suggest charging to 80% for the greatest longevity. Here's a helpful summary: Tips for extending the lifetime of lithium-ion batteries

 

[slmorgan42]

I wrote received wisdom because many authoritative websites - including those of Li-ion battery manufacturers - suggest charging to 80% for the greatest longevity. Here's a helpful summary: Tips for extending the lifetime of lithium-ion batteries

It wasn’t a criticism I was just agreeing I always tend to go with what the manufacturer says

 

[Gomev]

It's good to see people doing some research into owning an EV. Hopefully before buying their first or ASAP after.
Just like buying any shiny new thing we will spend our time loving and looking after it and following all best practice. However a year or two down the line when there are other shinier things around we slip into more comfortable habits that suit us rather then being governed by best dictates.
.....well at least I do.....

 

[maskull]

It's good to see people doing some research into owning an EV. Hopefully before buying their first or ASAP after.
Just like buying any shiny new thing we will spend our time loving and looking after it and following all best practice. However a year or two down the line when there are other shinier things around we slip into more comfortable habits that suit us rather then being governed by best dictates.
.....well at least I do.....

On the flip side of that is that some don't care at all . I arrived at a rapid charger this weekend to find a Tesla occupying the CCS . His SOC was at 93% so I asked if he was charging to 100% . He said he was because he had to get home to London ( about 160 miles ) . He knew 100% wasn't recommended on Rapid but was changing the car next year . So I suppose the lesson is always check the SOH in the used EV market .
In all fairness to him he left when he knew I as waiting for the CCS

 

[Staffex]

It wasn’t a criticism I was just agreeing I always tend to go with what the manufacturer says

Yes, but this manufacturer seems to be saying different things depending on where you look. The manual says fully charge but, as you point out, the website suggest 80%. Does anyone know who manufactures the MG5's HV battery? I wonder what their charging advice is.

Yes, but this manufacturer seems to be saying different things depending on where you look. The manual says fully charge but, as you point out, the website suggest 80%. Does anyone know who manufactures the MG5's HV battery? I wonder what their charging advice is.

I think you have to look at in context of how you use the car.

If like me I do very few miles and only slow charge once or twice every two weeks. I will not have much of an issue with the batteries needing to be equalised very often. So no need to 100% charge very often. I do 100% charge probably every three months or so when I do a long drive.

But someone who drives many miles a day and uses rapid chargers more often will need to equalise their battery’s more often.

 

[slmorgan42]

It's good to see people doing some research into owning an EV. Hopefully before buying their first or ASAP after.
Just like buying any shiny new thing we will spend our time loving and looking after it and following all best practice. However a year or two down the line when there are other shinier things around we slip into more comfortable habits that suit us rather then being governed by best dictates.
.....well at least I do.....

yeah I think making the switch to a EV requires a fair amount of research to understand the change you are making.

As I originally was waiting almost a year for a ZS before I made the switch to the MG5 FL I had plenty of time to read lol

This forum is always very helpful.

 

[shiv]

I think the most optimal method of maintaining the battery condition is to charge the car to 80% and never let it go below 50%. Which means you drive no more than ~60 miles between charges.

/s

 

[dragon2611]

It's quite easy to accidentally charge the pre facelift over 80% as if you aren't there to stop it or have some kind of timer (not so easy on a tariff like agile unless you don't care what you are paying) it's going to charge to 100% as there's no way to limit it from the car side.

 

[slmorgan42]

I think the most optimal method of maintaining the battery condition is to charge the car to 80% and never let it go below 50%. Which means you drive no more than ~60 miles between charges.

/s

As I drive very few miles this is exactly what I do. As I need to rely on pubic chargers (cannot have a home charger) this also work best.

 

[Robbob]

I always charge to 80% on fast chargers and 100% on slow chargers. Why? As I have to use it to go to work and if I messed about as suggested I would be charging every night. Surely this is just as bad as once maybe twice a week as present. doing what is suggested by some would mean many more charging cycles of the battery, this affects soh too. So far 40000 miles and soh 100%. The car to me is to get me from work and back with minimal fuss, long term who knows what will happen but it's is there to be used will my car battery have suffered or one that has been through so many more cycles? Just a thought!

 

[Jomarkh]

Is that an SR you have and do you mean 80% on a DC Rapid charger?

 

[Robbob]

Yes sr and yes dc rapid charger 80. Tend to use rapid discharges sparingly and depends on where I go some months 4 plus times others not at all

 

[Lovemyev]

Worth a watch ?.

 

[Gomev]

Worth a watch ?.

quite right, common sense should prevail as with most things in life.

 

[Petriix]

I always charge to 80% on fast chargers and 100% on slow chargers. Why? As I have to use it to go to work and if I messed about as suggested I would be charging every night. Surely this is just as bad as once maybe twice a week as present. doing what is suggested by some would mean many more charging cycles of the battery, this affects soh too. So far 40000 miles and soh 100%. The car to me is to get me from work and back with minimal fuss, long term who knows what will happen but it's is there to be used will my car battery have suffered or one that has been through so many more cycles? Just a thought!

It's objectively better to do a greater number of partial cycles in the middle of the voltage range than a smaller number of deeper cycles which approach the extremes. Shorter charging periods mean lower heat buildup.

Ultimately use it however you want. There are some small efficiency benefits to avoiding charging to 100% too frequently and we're ultimately just guessing on longevity; some of us err on the side of caution while others prefer the convenience of plug and forget. The main reason I don't charge to full (unless required for a long journey or the monthly balance charge) is to leave space for free charging from solar.