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Discussion Starter #1
My 2019 HSE has been more or less problem free.
Infotainment is 20.C and TCU is 15.2.

WattCat showed battery optimization less than 90% and capacity at less than 80kwh at 100%SOC.
I brought the car into my dealer/service shop, who have been great, by the way. After diagnostic tests completed, they identified 2/36 faulty cells in the traction battery.
The faulty cells and a 'battery charging module' have now been replaced.

In theory I should have gained 2/36 battery capacity, but still see only 79.7kwh on a 'fully charged' battery and WattCat tells me optimization is only 92%. Might this improve with a few discharge/charge cycles and some cell balancing?

Is something wrong? Or am I making too much out of nothing? Just want as much useable range as possible.

Thanks for any comments or advice?

Still love my car!!
 

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? No telling! But think about this; we have 36 (quote)"cells" in our battery. I believe our I-Pace battery is over 400volts when fully charged new. A Lithium Ion single cell is about 3.6 volts when fully charged. So you need more than a hundred cells to make an I-Pace battery yet we only have 36. I would submit that our I-Pace "cells" are more battery packs than cells. From all the info I can obtain, each and every battery cell(3.6v) in an electric car battery is not being balanced with all the other cells. Battery packs in our cars are being balanced. The same for Tesla, no way is every individual cell in a Tesla being balanced when the charger is balancing "cells". This will over time allow some individual cells in our cars to eventually drift down and the battery as a whole will loose capacity as they do. My opinion!
 

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Trielectric has much of this right. There are 36 modules of 12 cells each. The confusing part is that JLR calls the modules "cells" (same quotes are Trielectic's above). The total number of actual pouch cells is, you guessed it, 12 x 36 = 412.

WattCat's battery optimization is a bit of a hack (the developer, ardevd, happily admits to that) because it's based on incomplete information. True state of health statistics require considerable computing power that has to have the car plugged into a diagnostic device and it takes something like two hours for the calculations to complete. Or maybe less time but the point is that the calculations have to be performed off-vehicle. The computers in the car can't do it.

However, WattCat's kWh capacity estimate is probably pretty good. If you still see less than 80kWh after the 2/32 battery replacements, go back to the dealer and have them issue you a proper battery State-of-Health report that is generated by Pathfinder. There should be a record for each module ("cell") and it should show 95% or greater for each if they did the job right.

HTH keep us posted
 

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19 I-pace HSE Polaris/Fuji white with most options and a lot of accessories
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What was the temperature conditions under which the charging was done? I'm assuming this was after a level 2 charger was used to charge to 100%.
It has cooled off here for the next few months and WattCat's display on mine shows a few less kW (82.x) and a few less % optimization (96-97).
Warmer weather and a warmer battery gives higher numbers than cold conditions.
 

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Discussion Starter #5
Thanks all for your quick replies.
I'll have to double check with my service rep. I am pretty sure he spoke to me about 2 of 36 cells being faulty (not 2 of 12 of 36), but I can double-check.
The thing that has me puzzled is that they did their diagnostic work, performed some 'cell' replacement and repairs and my total battery capacity is the same or a little lower than before I brought the car in....
The car is presently charged to 100% after level 2 charging in a heated garage and WattCat tells me the battery capacity is 79.1 kwh. Before I brought the car in for battery repairs, I regularly achieved a 100%SOC battery capacity of 80.5-82kwh (after finally getting H264....). I'm hoping that a couple discharge and charging cycles will see my capacity increase. If not, I'll ask for a battery health report as you suggest.

Cheers and Happy New Year to all!
 

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Ayepace has a good point about cold temperatures. I have an unheated garage and it's consistently below freezing when I charge at night. WattCat displays 80-80.5 kWh at 100% SoC. I was seeing 83ish during the summer. I just had a battery health report and everything is fine. At 79.7 you're pretty close to what I'm seeing.

However, I agree with Sciencegeek that a battery health report is a good idea. I would be surprised if they didn't perform it after the repairs.

Last winter, prior to the H265 update, I was seeing numbers as low as 76.45 kWh.
 

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A traction battery does not have a kWh gauge. All that the BCM can measure is cell (or module) voltage and the behaviour of the voltage under load and over time.
The capacity calculated is an estimate, based on a model and the BCM's experience.
So for the car to even realise that a faulty module was replaced, it needs to experience it. Meaning that you should run it down to below 20.
After that, see what the BCM reports when fully charged.
While doing so, best record the kWh drawn but keeping in mind that a few 'ghost' kWh will disappear because discharge losses in the battery, especially when driving fast in cold weather.

Even so, the ambient temperature does have a measurable impact on the available capacity. For 100% charge, to me Wattcat reports 81-82kWh at 0°C, compared to 84-85kWh at 25°.
 

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Even so, the ambient temperature does have a measurable impact on the available capacity. For 100% charge, to me Wattcat reports 81-82kWh at 0°C, compared to 84-85kWh at 25°.
Those are the numbers I also have. External temp is -10c around here, and after a full night of charge at 7kw yesterday, the API reports a battery at 81.5kwh (EV_RANGE_VSC_REVISED_HV_BATT_ENERGYx100 param in the API). That value used to be around 86kwh in the summer.
 

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Discussion Starter #9
Quick Update

Have had the car back from JLR service for a couple days. Confirmed that what was replaced/repaired were 2 non-functioning cells in 2 of 36 modules ( so not 2 modules)... and a Battery Control Module.

Drove the car hard for 275km yesterday (nice drive :) then charged overnight on 7kw level 2 in my non-heated garage. Local temps around 5C (40F).

This morning WattCat reports 82.45kwh battery capacity and 96% optimization. The best numbers I've seen, since I got the car, but not 84 or 86kwh.

I'm disappointed to not have a battery that fills up as much as some of you, but happy that my service guys did the work and 'optimized' my Jag as best as they could.

Vehicle Software (TCU) is reported as version 15.2. Any chance I'll see more range by having this updated to 19.2? I kinda doubt it.

Happy New Year everyone.
 

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Those numbers are appropriate for this time of year and temperatures. At least I hope so. They match mine exactly. :)
The TCU is for communications and isn't related to the battery SOC reporting, charging, or energy usage.
 

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John,
Good that they fixed it!
82.45kWh at 5°C is just fine.

Lithium Ion batteries have a lower capacity at lower temperatures, simply because the chemical reaction that recreates the current is slower.
A 4% loss between 25°C and 5°C is perfectly normal.
If you want a higher number shown, you need to have a warmer battery (incidentally this will linearly increase the optimisation percentage reported by Wattcat).
 

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Discussion Starter #12
Once again, thanks all. I very much appreciate your knowledge and willingness to share. I am reassured that my car is 'within spec'.
 

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I am seeing 44 kWh with WattCat
at 100% and 209 miles per GOM. Battery temp? Garage about 40 F.
Would the kWh capacity as read my WattCat vary a lot if the battery was much colder than 40 degrees?
I just had service and the batteries tested around 92.5%. (But I don't think they were charged to 100% before test)
In fact 1 module read 84%.
So If the batteries were 0k, could there be a problem with the BCM? The dealer has no clue.
Battery energy control system: BP-AAG-BD-AD-BE
 

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One other thing I noticed that I failed to mention, when I start charging, the display reads say 4 hrs. to fully charge.
But when timed, the actual charge time to reach full is about 2 hrs. or only half that as predicted.
 

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One other thing I noticed that I failed to mention, when I start charging, the display reads say 4 hrs. to fully charge.
But when timed, the actual charge time to reach full is about 2 hrs. or only half that as predicted.
Yes. Sure sign of compromised battery, mine did that too when my first one had a bad battery
 
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