Safe to charge to 100%?

Jazzy2002

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About to purchase a MG ZS, is it safe to charge to 100% all the time? On the Tesla, it is normally recommended to charge to 80% on a daily drive. Not sure it applies to the ZS.
 
Lithium ion battery don't like sitting on a full 100% charges soTesla don't recommend you charge to the max unless you are going on a road trip. Maybe there is a hidden battery capacity to allow a fake 100% indicated charge on the mg.
 
I would recommend the same with the MG, only fully charge if it’s needed rather than let it sit there with 100%
 
I don’t think you can charge to 100%. The eZS considers 42.5kWh to be full charge, leaving 2.5kWh to prevent full charge/discharge.

It does look like the cells in the eZS are being run at 4.2 volts which is a shame. That is similar to Tesla’s overdrive mode which is more geared towards capacity than longevity. Which is why Tesla recommends using it only for trips.

You’re right lithium batteries hate holding full charge or being completely discharged. I keep my car between 20 and 80% but I wouldn’t recommend that for anyone else. Battery degradation is inevitable and will be managed by the computer.
 
I haven't got the car yet. Is there any way to limit the charging % in the car? Cheers
 
I haven't got the car yet. Is there any way to limit the charging % in the car? Cheers
Not on the car.
You can either manually stop the charge (unlock the car and disconnect) or put a timer on the (home) charger or power supply to stop before it's full.
 
Hi Folks,

Is there any easy route to viewing the SOC while the car is charging? I know on AC, if I press the lock button on the car, whilst it is already locked and charging, it will bring up the display for a short time, showing the time remaining and the battery charging picture.
But on DC, when your sitting in the car, is there any setting where you can see the current SOC and time remaining? I know if you turn on the car and turn it off again,the battery thing comes up as for AC. My ioniq had a screen that told you basically all you needed to know. With the MG, the actual DC charger shows more information than the car! Or am I missing a screen setting somewhere?

Another thing, the max I seem to get is 26kw on the rapid charger. I normally charge at home, but today I used a rapid and was at 40% SOC roughly. As I got close to 90% I was getting 16kw, which I do know is normal. But what kind of speeds are you folks getting from the rapid charger. I was at a high power 150kw one today. Then I tried a 50kw one and my speeds were the same
Thanks in advance.
 
To get the best speeds you need to be below 20% state of charge (last dash on the battery gauge is 25%), ideally under 10% on rapids. This is when the battery can take a higher amp and voltage level to approach the max speed of 80kW (if on a 100kW+ charger), however Bjorn Nylands tests show there is little difference between a 50kW CCS and 80 with the MG as it throttles sooner at the higher speed.
 
I don’t know of anyway to see the SOC % except for turning the car on then off. I wish there was one.

I’ve used over 500 kWh from rapid chargers so far. I usually get 40/42 kWh if I’m below 80%. Then it drops to 20/15 kWh and finally 5kWh for the last 5%.
 
This was charging from 35%
1601222995350.png

This from 8% both on Instavolt chargers
1601223066989.png
 
I don’t know of anyway to see the SOC % except for turning the car on then off. I wish there was one.

I’ve used over 500 kWh from rapid chargers so far. I usually get 40/42 kWh if I’m below 80%. Then it drops to 20/15 kWh and finally 5kWh for the last 5%.
Thanks a mill for that
 
Here is a pic I took when I plugged out today. This seems slow to me. I was using a 150kw charger
 

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Hi all,

I saw the post and did some research. The MG ZS does charge to 100% (and yes that isn't good for the battery life) but. It's not that significant.

Most of you (I think) drive between 10.000 and 15.000 km per year. This means you charge the car around 2 to 3 times a week so that would roughly be around 150 battery cycles a year.

According to below chart that would result in a battery loss in 10 years of 1500 cycles leaving you with 88% capacity. A 5% difference to charging 25% to 85%.

DST-cycles-web2.jpg

source: How to Prolong Lithium-based Batteries - Battery University

The main colporate for battery degration is fast charging. Listed in the manual it should be avoided.

GeoTab-fast-charging-chart.jpg


source: New Data Shows Heat & Fast-Charging Responsible For More Battery Degradation Than Age Or Mileage

Since the MG ZS EV is produced by SAIC who also makes the VW e-golf (and chineese are famous for replicating technologies) i thnk you should expect the same result as the battery from the e-golf.

source: Volkswagen China launches the e-Lavida, e-Golf and e-Bora

Anyway, you have 8 years warranty on the battery at 70% capacity. In that case you should still have more then enough range for daily commutes and that is still more than the new 2020 Mazda MX-30, or a BMW i3 from 2017

download.png


Green: All EV vehicles
Orange: VW E-golf
 
Useful information above. However I don't think there is information out there if you don't do the whole cycle. If you charge to full then use to 70% then recharge to 100% again. Do that for annual 10k miles, the battery degredation would be different?
 
Useful information above. However I don't think there is information out there if you don't do the whole cycle. If you charge to full then use to 70% then recharge to 100% again. Do that for annual 10k miles, the battery degredation would be different?


Very true, the chart shows that charging above 75% or below 65% impacts battery life. So it should give you a good estimate.

Personally charging mostly from 65% to 100% 3 times a week.
 
Life is too short to worry about charging regime. Its just short sighted not to include a schedule or charge limit on the car for charging. Wonder if there will be a software update to correct this.
 
Life is too short to worry about charging regime. Its just short sighted not to include a schedule or charge limit on the car for charging. Wonder if there will be a software update to correct this.
Hi Jazzy,

Fully agree, I don't give a fiddler's fart about a bloody stupid charging regime, I plug it in EVERY night when it's dark a clock and if the battery degrades then so what it's only going to affect the range nothing else and most people will only keep their car until the PCP expires. I am however fully aware if one was keeping the car long term (over and beyond the warranty) then yes it might be prudent to worry some what about the battery but if you are not then just enjoy the car and keep its ownership as stress free as possible. I also whilst driving around town or on a journey will within the return range then I use the car to its full and do NOT worry at all about achieving some magic miles per Kw, ie I make use of instant torque and power and enjoy myself, it is only a car, a tool , use it with enjoyment.

Regards

Frank

PS Misread your post, oops, I think the opposite obviously.
PLS There is a function to protect the Battery it's the Battery Management System, let it do it's job and stop worrying about the battery, it's not in the Manufacturers interest to have lots of warranty claims on the battery so hence having a BMS , stop worrying about a charging regime and enjoy the car.
 
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I'm not worried either, even if I was, from what people are saying, I think my normal use seems to be good for the battery anyway.
I usually let it get down to around 70 miles left on the GOM then add 30-40 miles for free at Tescos, on average about once a week (occasionally twice) as I only do around 40 miles a week.
I've only charged it to full 3 times, once when I first got my home charger, to make sure it was working, then on two occasions where I went to the coast for a day out, just topping up to 95% on the way back on a CCS.
I think the fuss about manual battery management is much ado about nothing anyway, if the battery needs replacing in say 8 or 10 years time, you may get a newer technology battery that gives better performance in range and longevity and cost less.
 
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