Which mileage indicator is more accurate?

BrianS

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The ZS Excite has 2 different mileage indicators. the markers at the bottom of the clock or the actual reading Mileage remaining?
I am generally getting 16 miles for each marker but when it reaches the last marker the actual mileage indicates 50 miles left.
Anyone who can advise would be very helpful
Brian S
 
I am generally getting 16 miles for each marker but when it reaches the last marker the actual mileage indicates 50 miles left.

I guess you are thinking about range remaining; it's all a guesswork that depends on what you do next with the car ... go uphill for 10 min and your range will drastically drop. go downhill and it will increase. Don't rely on either as accurate and just recharge when you feel you have to. I never drive if the charge is below 20% unless I'm almost home.
Not the answer you wanted but that's how it is - guesswork. If I had to go for one, numerical should be closer to (not quite-)accurate
 
Thank you.. I know the volt should be 450 on a full charge but i generally get 449/448. to get to 450 i believe I have to granny charge so each cell is full, but to do this i will have to charge after all the marks have gone and that would probably leave me with about 30 miles available, should i take a chance?
 
Thank you.. I know the volt should be 450 on a full charge but i generally get 449/448. to get to 450 i believe I have to granny charge so each cell is full, but to do this i will have to charge after all the marks have gone and that would probably leave me with about 30 miles available, should i take a chance?

Search forum for balancing, there are plenty of discussions. You leave the battery to go down to 10% and then slow charge to 100% and leave it for another hour to slowly balance after it reaches 100%.
Mind you, plenty of people don't do it and the batteries still seem just fine ...
 
Thank you.. I know the volt should be 450 on a full charge but i generally get 449/448. to get to 450 i believe I have to granny charge so each cell is full, but to do this i will have to charge after all the marks have gone and that would probably leave me with about 30 miles available, should i take a chance?
This is how I use the guess-o-meter. Put your destination into the sat-nav and see what the overall distance is.

Subtract that distance from the estimated range and see what you have remaining.

On an outward journey, if it's 50 miles or more, I don't look for a charger. If it's under 50 miles, I make a note of where the chargers are near to my destination.

Returning home, because I know where the local chargers are, and that I have a home charger, I go for 30 miles remaining on the GOM.

Recently, I did a long journey without any planning, just using Google Maps on Android Auto, with the local chargers search option when I needed a charge and it worked a treat.
 
Thank you.. I know the volt should be 450 on a full charge but i generally get 449/448. to get to 450 i believe I have to granny charge so each cell is full, but to do this i will have to charge after all the marks have gone and that would probably leave me with about 30 miles available, should i take a chance?
You can conduct a balance from any A/C powered unit, it does not have to be a Granny unit.
Not from a D/C rapid unit of course.
 
You can conduct a balance from any A/C powered unit, it does not have to be a Granny unit.
Not from a D/C rapid unit of course.

apparently, seen on some posts here, some "smarter" 7kW chargers stop and disconnect at 100% and might not continue trickle charging to balance ... I can't check as I only use granny one ...
 
Many thanks for all the above replies however if i have 1 marker left on my indicator which would give me about 16 miles but the GOM is stating 50ish, what is the more accurate? does this mean once the last marker disappears, will their be 30 miles maybe left?
 
Many thanks for all the above replies however if i have 1 marker left on my indicator which would give me about 16 miles but the GOM is stating 50ish, what is the more accurate? does this mean once the last marker disappears, will their be 30 miles maybe left?

the only accurate answer to that is to try and see what happens.
there was a YouTube video of someone saying there is about 30km remaining after battery charge shows 1% (from memory). Would I trust it? No.
 
I guess you are thinking about range remaining; it's all a guesswork that depends on what you do next with the car ... go uphill for 10 min and your range will drastically drop. go downhill and it will increase. Don't rely on either as accurate and just recharge when you feel you have to. I never drive if the charge is below 20% unless I'm almost home.
Not the answer you wanted but that's how it is - guesswork. If I had to go for one, numerical should be closer to (not quite-)accurate
What you really need to keep an eye on is the miles per kWh. If it is high then your range will be further. I have achieved 5.8 mi/kWh. The range is only an estimate of what the battery can achieve within a given temperature range. In winter it is low because the battery is used to heat the car, and the electrons are a little sluggish. If you add the remaining range and the distance covered when driving you can see the performance. You will find that avoiding the use of brakes when slowing down gives you a better range. If the range is about 375, most of the charge is static. When you move of the range drops suddenly because this static dissipates.
When you go below 40%, the fun and games start because the voltage drop makes the battery work harder to provide the same performance as at 100%. I try to avoid driving below 20%. Although I have met a driver who was at 1%.

apparently, seen on some posts here, some "smarter" 7kW chargers stop and disconnect at 100% and might not continue trickle charging to balance ... I can't check as I only use granny one ...
Once a battery hits 100% the computer stops the charger. There is no trickle charging. There are transformers in the car to stop fast charging and damaging the battery. If you want to maximise the cells then charge the battery from 80% on a three pin plug (2kW) over night. It reduces the magnetic repulsion induced by electrons entering the battery. On my 72kWh battery I get 334~357 miles. I mainly use the 3pin plug to charge with. If I have to use a rapid charger, I only go up to 80%, then 100% at home.
 
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There is no trickle charging. There are transformers in the car to stop fast charging and damaging the battery.
Huh?

When fast charging, the BMS tells the big charger how fast to charge.
It reduces the magnetic repulsion induced by electrons entering the battery.
? What has magnetism got to do with charging?

some "smarter" 7kW chargers stop and disconnect at 100% and might not continue trickle charging to balance ... I
I don't believe any would. There is a voltage level handshake to terminate the charge, and the car's Battery Management System has control of that. The EVSE (AC "charger") doesn't (or shouldn't) care if the car is drawing less current than the pilot signal indicates. It's a current limit (maximum), not a set point.
 
Huh?

When fast charging, the BMS tells the big charger how fast to charge.

? What has magnetism got to do with charging?
Everything. You can think of it as heat. When electrons move they interfere with other magnetic fields around them. The longer the charge the more the disturbance in the battery. If you super charge a ZS with a 125 kW charger the battery maximises at 80% before you give up charging. If you use a 50 kW charger then you get 95% under an hour. The other 5% could take upto 5 hours. If you want to maximise your range then you have to slow down your charger to 2 kW to reduce the magnetic disturbances in the battery. A bit like crowd control in a stadium where people get enough time to find there seats by entering the right stile to avoid bumping into each other. The transformers in the ZS are there to stop these magnetic fields from getting to large and forming dendrites in the battery.
 
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If you super charge a ZS with a 125 kW charger the battery maximises at 80% before you give up charging.
I believe that's because the Battery Management System will see some cell voltages become too high with the high charge current, and will tell the rapid charger to cut the current to a quite low value to protect those cells from over-voltage. The rapid charger takes this as a sign that the session is over; other drivers can make better use of the rapid charger.

If you use a 50 kW charger then you get 95% under an hour.
I believe that's because at the lower charge rate, the BMS isn't forced to lower the requested charge current too much, and the rapid charger allows the charge to continue for longer. Usually it would still give up the charge well before 100% if that would take hours.
The transformers in the ZS are there to stop these magnetic fields from getting to large and forming dendrites in the battery.
If you mean that the BMS will tell the on-board charger (a DC-DC power converter, something like a transformer for DC) to prevent over-charging the cells in the main battery to prevent plating, then I agree. Dendrite growth I think happens at low cell voltage, though it seems to depend on many factors.
 
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