charging to 100%

[andrewhs]

Occasionally our car will be at 80%charge overnight but next day is bright and sunny so we want to use the surplus from the solar panels to top up the car , so i have been resetting it to 100% . Is this a bad thing to do ? ie is there a limit as to how many times you charge it to 100% ?

PS recently at 20 C plus temp, the car at 100% charge was showing a range of 260 miles which i was quite pleased with

 

[Scoozy]

I rest my case battery's are made to charge full so i charge always to 100% my Luxury, maybe this will give after more years a little more degradation but cars goes away every 5 years. My iPhone i charge always every day full has the same chemical battery so now 4 years without almost any loss so the car wont have any problem with, they're made for it.

 

[DBedford]

I’d charge to 60% and to up to 80%

 

[Ian Key]

Occasionally our car will be at 80%charge overnight but next day is bright and sunny so we want to use the surplus from the solar panels to top up the car , so i have been resetting it to 100% . Is this a bad thing to do ? ie is there a limit as to how many times you charge it to 100% ?

PS recently at 20 C plus temp, the car at 100% charge was showing a range of 260 miles which i was quite pleased with

Depends which battery you have. If it's the SR no problem but if it's the LR, as long as you don't let the car sit at 100% and use it the following day, it should be OK.

 

[Jomarkh]

I have the same issue at weekends so don't charge Saturday mornings then there is space for excess solar

 

[Chequers]

I rest my case battery's are made to charge full so i charge always to 100% my Luxury, maybe this will give after more years a little more degradation but cars goes away every 5 years. My iPhone i charge always every day full has the same chemical battery so now 4 years without almost any loss so the car wont have any problem with, they're made for it.

Your iPhone does not have the same chemistry as your Luxury.
The Trophy/Luxury battery will degrade faster is left charged at 100% for a long time.
This is common knowledge with LMC batteries.
But it's your car so do whatever pleases you.

 

[Themist0]

This is interesting article


i intend keeping my trophy for 8-10 years so will try to look after the battery, only charging up to 100% once a month to balance.

I suspect this will end up being a moot debate over the years as in 10 years my car will be like an iPhone 3 compared to what is to come. And when it comes to resell, will people insist on a battery health check?

 

[tsedge]

The advice from MG is:

• Normally charge to 80%
• 100% charge at least once a month and when you need it.

Regularly charging to 100% will have an effect, will be minimised if you immediately discharge the battery and use it, but will probably still affect overall degradation.

However, we are only talking a few percent over years so unless you are keeping the car for many years, it really won't make any difference.

Bear in mind that even Nissan Leafs, who don't have active thermal management and degrade much more quickly are fine for the first 5 years or so and even when older there are plenty of people running around with 2/3 or 1/2 the original range without problems.

With the MG4 degradation will be much less than this whatever you do with charging.

 

[Rolfe]

Are all Nissan Leafs like that, or was it just earlier models?

 

[AndyL61]

This is interesting article


i intend keeping my trophy for 8-10 years so will try to look after the battery, only charging up to 100% once a month to balance.

I suspect this will end up being a moot debate over the years as in 10 years my car will be like an iPhone 3 compared to what is to come. And when it comes to resell, will people insist on a battery health check?

You don't have to charge to 100% to balance. If you set to 90% or 80% and leave it plugged in and charging it doesn't go passed your set limit but does continue for quite a while at very low power draw in exactly the same way as it does at 100% . So I believe it will balance at the limit you set. Try it you will see it .

 

[tsedge]

Are all Nissan Leafs like that, or was it just earlier models?

They are still like that, however later models have bigger battery packs so the impact is less. There are replacements available.

The Leaf is an excellent vehicle and nobody should exclude it from their list unless they are keeping it for years and years.

Nissan have decided to stick with the original design presumably because it is cheap to make and to keep the car as a good value option.

The Leaf still uses Chademo, which is a bigger issue really than battery life.

 

[Rolfe]

Thanks. I was just asking because friends of mine have a Leaf, and have had it for several years now. They're still quoting the nominal range for the battery (which is somewhere between the SR and the LR) and seem quite happy with it. I agree I'd be a bit wary of CHAdeMO.

 

[siteguru]

You don't have to charge to 100% to balance. If you set to 90% or 80% and leave it plugged in and charging it doesn't go passed your set limit but does continue for quite a while at very low power draw in exactly the same way as it does at 100% . So I believe it will balance at the limit you set. Try it you will see it .

The only downside I can see to that is that balancing at a lower SoC may not balance all the battery cells - it might just balance the active cells which are achieving the current SoC.

(I have no evidence for this - it is merely a musing).

 

[tsedge]

The other downside is on SR due to the (mostly) flat charge curve much easier for it to balance at 100%

 

[siteguru]

Given that the SR is recommended to be charged to 100% anyway, I don't really see that as a downside.

 

[Rolfe]

Given that the app won't even allow the SR to be charged to less than 100%, I feel perfecty comfortable in simply going there. As I'm doing right now - came back yesterday at 30%, didn't bother with the granny charger, just took the car to the rapid charger at 2.30 this afternoon. Picked it up at 3.24 (maximum time allowed) at 88%, then straight on to the granny charger to finish at 6.50 then balance.

Simples.

Given that as of today my domestic electricity is now marginally cheaper than that rapid charger, I'll probably save myself the ten minutes walk in future, unless I'm in a real hurry to charge after a long journey. Which will be even simpler, of course.

 

[okohll]

The only downside I can see to that is that balancing at a lower SoC may not balance all the battery cells - it might just balance the active cells which are achieving the current SoC.

(I have no evidence for this - it is merely a musing).

Don’t know, I’d have thought that 70% = all cells at 70% charge rather than 70% at full charge. I can confirm my charge to 70 today did a balance at the end, it looks like it anyway from the graph. There must be a reason MG suggest 100 now and again though.

 

[AndyL61]

The only downside I can see to that is that balancing at a lower SoC may not balance all the battery cells - it might just balance the active cells which are achieving the current SoC.

(I have no evidence for this - it is merely a musing).

Apparently the balance works to equalise all cells to the same level so should balance all the cells at whatever SOC that you have set . So it should be balanced but you don't need to charge to 100% , otherwise there would be no point in it taking over an hour at something like 0.1 kw once it has reached the SOC set limit.

 

[tsedge]

Apparently the balance works to equalise all cells to the same level so should balance all the cells at whatever SOC that you have set . So it should be balanced but you don't need to charge to 100% , otherwise there would be no point in it taking over an hour at something like 0.1 kw once it has reached the SOC set limit.

You do need to charge to 100% at least once a month, that's what MG say.

 

[AndyL61]

You do need to charge to 100% at least once a month, that's what MG say.

That's right they do but they don't mention that it also balances below 100% . Mine is on a dumb EVSE so gets balanced virtually every time I charge , don't know wether that's good or not. Yes I do sometimes go to 100% .