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LFP strange behaviour

SKA

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Hi all. I wrote about this a month or so ago during the cold times when all of a sudden it had lost 10% just parking up. I know the temperature had an impact and i know the range etc...

I have been keeping a close eye on it but I don't drive it enough, and today, after morning school run I got home with 57% left, and when I left again on afternoon school run it had 44% , so the 13% disappeared into thin air (car was untouched) . And I got home after the 5 mile round trip with 37% left. The way I drive the zs , my "consumption " is at least 3.5mi/kWh constantly, may be even 3.8 at times. So the 5 mile trip I expect around 3% of usage and not 7

Also it was very strange that I had a lot of miles out at 62% (it was stuck at 62% for a very long time, probably 10-15 miles)

So my conclusion is that I either have a duff battery (which I am not sure if the dealer can check) or the LFP flat line behaviour makes it unpredictable for battery capacity in the middle. So I guess the drop of voltage for that few % around the 62% was so little that the car could not measure and after that it just dropped so much to make up the lost of the previous.

I guess if I repeatedly try from 100%-20% in this kind of weather (high singles low tens) and see if my mileage coverage is about the same or not. Treating it like an ICE with a faulty fuel gauge but knowing roughly how much I can get out of a full tank scenario.

I do not rely on the range, as I only consider % against mi/kWh

Thanks all
 
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2 charges ago was charged to 100%

Then it was more or less from 20 or 30 to 85%
That's you probably then LFP behave better or at least the BMS if you start the day afresh at 100%

Edit there was a member on here recently that tried equalisation charge on there standard range and it took 3.5h extra from 100% they was also charging the battery like you the BMS just can't handle the LFP without 100% starting point especially after charge then when you add on unbalance cells in the mix you gonna get percentage readings all over the place
 
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Did you turn off the EVSE at 100% or leave it until the car stopped drawing current?
This I leave until it stops drawing. So when app says pulling 0kw from charger.

That's you probably then LFP behave better or at least the BMS if you start the day afresh at 100%

Edit there was a member on here recently that tried equalisation charge on there standard range and it took 3.5h extra from 100% they was also charging the battery like you the BMS just can't handle the LFP without 100% starting point especially after charge then when you add on unbalance cells in the mix you gonna get percentage readings all over the place
Oh, I understand we can charge to 100% but was not aware that we "should" do so every time on every charge. Or cos some might say this and others might say not good to charge to 100% every time even LFP... I guess time will tell.. still too new for anyone giving any real feedback yet I guess. 😔
 
Oh, I understand we can charge to 100% but was not aware that we "should" do so every time on every charge. Or cos some might say this and others might say not good to charge to 100% every time even LFP... I guess time will tell.. still too new for anyone giving any real feedback yet I guess. 😔
This is why MG removed the charge limit on SR to encourage 100% charging Tesla done the same on there LFP before they made the change people where moaning of percentage loss with out driving the chance in temperature changes to the voltage just a tiny bit confused the BMS
 
Another reason why I thought I have a dodgy battery is that even full charged after equalisation AND reset the GOM , it only shows 192/193 miles in range and not 199 like previous and I am not talking about extreme cold weather, but like today, at 14oC.

Do others SR owners get similar stats ?

Thanks
 
Another reason why I thought I have a dodgy battery is that even full charged after equalisation AND reset the GOM , it only shows 192/193 miles in range and not 199 like previous and I am not talking about extreme cold weather, but like today, at 14oC.

Do others SR owners get similar stats ?

Thanks
In LFP terms 14c is still cold 24c is considered optimal and to be fair your probably looking at air temp remember them batterys have been outside all night they are probably colder than 14c
 
Fair play, would have thought 14 is normal, 24 is better 😅. I will try 100-percent charge every time for some time and see if this improves...thanks all

May I ask if other SR owners what range the GOM shows when full charge after equalisation and reset on GOM in this sort of weather ? (Say 10-15oc) just to see if I am the odd one out. 😂

Thanks
 
May I ask if other SR owners what range the GOM shows when full charge after equalisation and reset on GOM in this sort of weather ? (Say 10-15oc) just to see if I am the odd one out. 😂

Thanks
That's not going to be useful information for you.

The GOM is just guessing based on not just SoC but also your previous consumption which varies dramatically.

With the balancing you should be looking for consistency in discharge across the capacity as you use it (or is it is stood overnight) With no weird sudden drops.
 
After reset "should" give factory estimated range not based on previous consumptions, is that not correct ?
 
After reset "should" give factory estimated range not based on previous consumptions, is that not correct ?
Yes this is correct to a large degree, however ambient temperature WILL play a part in this situation.
I have been taking records of this when we owned a ZS EV Gen1 for over two years and almost 20,000 miles and have continued to do so on our ZS EV Gen2 for the last 12 months and 10,000 miles.
Charging totally at home etc etc.
The fluctuations starts as soon as the ambient temperature falls.
 
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Yes this is correct to a large degree, however ambient temperature WILL play a part in this situation.
I have been taking records of this when we owned a ZS EV Gen1 for over two years and almost 20,000 miles and have continued to do so on our ZS EV Gen2 for the last 12 months and 10,000 miles.
Charging totally at home etc etc.
The fluctuations starts as soon as the ambient temperature falls.
Falls below how cold if you don't mind me asking ?
 
In my current experience, I'm finding I'm getting better mileage once things creep above 8-10C.
 
Should you try to charge to 100% with an LFP on a DC charger?
 
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